Researchers Database

TANABE, Shinsuke

    Center for Marine Environmental Studies Professor
Last Updated :2021/03/05

Researcher Information

Degree

  • Doctor of Agriculture(Nagoya University)

URL

J-Global ID

Research Interests

  • 生態毒性学   環境化学   Ecotoxicology   Environmental Chemistry   

Research Areas

  • Environmental science/Agricultural science / Environmental policy and society
  • Environmental science/Agricultural science / Environmental impact assessment
  • Environmental science/Agricultural science / Environmental dynamics

Academic & Professional Experience

  • 2015/04  Ehime UniversityCenter for Marine Environmental Studiesセンター長
  • 2012/01  Ehime University特別栄誉教授
  • 1999/04  Ehime UniversityCenter for Marine Environmental Studies教授
  • 1996/10  Ehime UniversityFaculty of Agriculture, Department of Bioresources教授
  • 1988/12  Ehime UniversityFaculty of Agriculture, Department of Bioresources助教授
  • 1988/03  アメリカ合衆国テキサス農工大学文部省在外研究員
  • 1977/09  Ehime UniversityFaculty of Agriculture助手

Education

  •        - 1985/02  Nagoya University  農学博士
  •        - 1975/03  Ehime University  Graduate School of Agriculture  農芸化学専攻修士課程
  •        - 1975  Ehime University  Graduate School, Division of Agriculture
  •        - 1973/03  Ehime University  Faculty of Agriculture  農芸化学科
  •        - 1973  Ehime University  Faculty of Agriculture

Association Memberships

  • Society of Environmental Toxicology and Chemistry   American Chemical Society   Society for Marine Mammalogy   日本環境化学会   日本内分泌撹乱化学物質学会   日本環境毒性学会   環境放射能除染学会   日本微量元素学会   日本環境科学会   日本化学会   日本薬学会   日本生態学会   日本鳥学会   日本哺乳類学会   日本セトロジー研究会   日本ウミガメ協議会   日本海洋学会   日本海洋学会沿岸海洋研究部会   日本水産学会   日本地球化学会   日本農芸化学会   日本比較生理生化学会   ダイオキシン・環境ホルモン対策国民会議   日本極地研究振興会   日本BICER協議会   東南アジア国際農学会   日本農学アカデミー   The International Society for Southeast Asian Agricultural Sciences   The Society for Marine Mammalogy   

Published Papers

  • Eguchi A, Nomiyama K, Sakurai K, Kim Trang PT, Viet PH, Takahashi S, Iwata H, Tanabe S, Todaka E, Mori C
    Environmental pollution (Barking, Essex : 1987) 242 (PartA) 98 - 105 0269-7491 2018/11 [Peer-reviewed]
  • H. W.I. Gray, S. Nishida, A. J. Welch, A. E. Moura, S. Tanabe, M. S. Kiani, R. Culloch, L. Möller, A. Natoli, L. S. Ponnampalam, G. Minton, M. Gore, T. Collins, A. Willson, R. Baldwin, A. R. Hoelzel
    Molecular Phylogenetics and Evolution 122 1 - 14 1095-9513 2018/05 [Peer-reviewed]
     Scientific journal 
    Phylogeography can provide insight into the potential for speciation and identify geographic regions and evolutionary processes associated with species richness and evolutionary endemism. In the marine environment, highly mobile species sometimes show structured patterns of diversity, but the processes isolating populations and promoting differentiation are often unclear. The Delphinidae (oceanic dolphins) are a striking case in point and, in particular, bottlenose dolphins (Tursiops spp.). Understanding the radiation of species in this genus is likely to provide broader inference about the processes that determine patterns of biogeography and speciation, because both fine-scale structure over a range of kilometers and relative panmixia over an oceanic range are known for Tursiops populations. In our study, novel Tursiops spp. sequences from the northwest Indian Ocean (including mitogenomes and two nuDNA loci) are included in a worldwide Tursiops spp. phylogeographic analysis. We discover a new ‘aduncus’ type lineage in the Arabian Sea (off India, Pakistan and Oman) that diverged from the Australasian lineage ∼261 Ka. Effective management of coastal dolphins in the region will need to consider this new lineage as an evolutionarily significant unit. We propose that the establishment of this lineage could have been in response to climate change during the Pleistocene and show data supporting hypotheses for multiple divergence events, including vicariance across the Indo-Pacific barrier and in the northwest Indian Ocean. These data provide valuable transferable inference on the potential mechanisms for population and species differentiation across this geographic range.
  • Tomoko Oguri, Go Suzuki, Hidenori Matsukami, Natsuyo Uchida, Nguyen Minh Tue, Le Huu Tuyen, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe, Hidetaka Takigami
    The Science of the total environment 621 1115 - 1123 0048-9697 2018/04 [Peer-reviewed]
     
    In developing countries, inappropriate recycling of e-waste has resulted in the environmental release of toxicants, including heavy metals, that may have deleterious health effects. In this study, we estimated daily metal intakes in five households in a Vietnamese village located in an e-waste processing area and assessed the health risk posed by exposure to the metals. Garden soil, floor dust, 24-h duplicate diet, and ambient air samples were collected from five households in northern Vietnam in January 2014. All samples were acid-digested, and contents of Cd, Cu, Mn, Pb, Sb, and Zn were measured by using ICP mass spectrometry and ICP atomic emission spectroscopy. In addition, the soil, dust, and diet samples were subjected to an bioaccessibility extraction test to determine bioaccessible metal concentrations. Hazard quotients were estimated from bioaccessible metal concentrations, provisional tolerable weekly intakes, and reference doses. Garden soil and floor dust were estimated to be mainly contributors to daily Pb intake, as indicated by calculations using bioaccessible metal concentrations and the U.S. Environmental Protection Agency soil plus dust ingestion rate. Diet was suggested to contribute significantly to daily Cd, Cu, Mn, Sb, and Zn intake. Estimated metal exposures via inhalation were negligible, as indicated by calculations using International Atomic Energy Agency reference inhalation rates. The maximum hazard quotients were calculated as 0.2 (Cd), 0.09 (Cu), 0.3 (Mn), 0.6 (Pb), 0.2 (Sb), and 0.5 (Zn), on the basis of bioaccessible metal concentrations. The contributions of Cd, Cu, Mn, Sb, and Zn except Pb to potential noncancer risk for adult residents of the five households in the e-waste processing area may be low.
  • Rumi Tanoue, Imari Kume, Yasuo Yamamoto, Kohki Takaguchi, Kei Nomiyama, Shinsuke Tanabe, Tatsuya Kunisue
    Journal of Chromatography A 1539 30 - 40 1873-3778 2018/03 [Peer-reviewed]
     Scientific journal 
    Thyroid hormones (THs), which mainly consist of 3, 3′ 5-triiodo-L-thyronine (T3) and L-thyroxine (T4), play a critical role in regulating biological processes such as growth and metabolism in various animal species. Thus, accurate measurement of T3 and T4, especially physiologically active free (protein-unbound) forms, in serum/plasma is needed for the evaluation of TH homeostasis. However, such high-precision determination of free THs is lacking for non-human species. The present study aimed to develop a highly sensitive and reliable liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for the determination of six free THs in serum/plasma, which is applicable to not only humans but also non-human species. Two different physical separation steps, ultrafiltration (UF) and equilibrium dialysis (ED), were examined to obtain the free TH fraction. Several experimental conditions were carefully optimized and validated for UF or ED using the commercially available bovine serum. As a result, UF at 1100 × g and 37 °C for 30 min with a 30 kDa ultrafiltration device (Centrifree YM-30, Millipore) yielded excellent precision (CV: < 10%). The optimized ED step also yielded high precision (CV: < 10%) and the measurement values were approximately equal to those of UF, but at least 16 h were required to reach equilibrium. Thus, UF combined with LC–MS/MS was finally chosen, in terms of the time needed for the measurement. Acceptable accuracy (recovery: 70%–110%) and intra- and inter-day precision (CV: < 10% and < 12%, respectively) were obtained, when triplicate analyses in three different days were conducted using the bovine serum. The developed analytical method was successfully applied to the determination of free THs in serum/plasma samples of humans, cats, and dogs. Furthermore, comparison with free T4 concentrations measured by a common immunoassay method evidently indicated that the ultrafiltration-LC–MS/MS method developed in this study can increase the specificity and accuracy of TH measurement.
  • Sónia D. Coelho, Tiago Maricoto, M. Ramiro Pastorinho, Takaaki Itai, Tomohiko Isobe, Tatsuya Kunisue, Shinsuke Tanabe, Ana C.A. Sousa, António J.A. Nogueira
    Journal of Geochemical Exploration 183 187 - 190 0375-6742 2017/12 [Peer-reviewed]
     Scientific journal
  • Akitoshi Goto, Nguyen Minh Tue, Masayuki Someya, Tomohiko Isobe, Shin Takahashi, Shinsuke Tanabe, Tatsuya Kunisue
    SCIENCE OF THE TOTAL ENVIRONMENT 599 340 - 347 0048-9697 2017/12 [Peer-reviewed]
     Scientific journal 
    The present study examined the occurrence and potential sources of mono-to octa-brominated dibenzo-p-dioxins/dibenzofurans (Mo-OBDD/Fs) in Tokyo Bay, Japan, using surface sediments and Pb-210-dated sediment cores (covering the period 1895-2000) collected in 2002. The results showed a clear difference in the spatio-temporal trend between PBDFs and PBDDs. The spatial distribution of PBDF concentrations in the surface sediments showed a decreasing trend from the head to the mouth of the bay, which was similar to that of polybrominated diphenyl ethers (PBDEs) reported previously for the same sediment samples. In the sediment cores, PBDF and PBDE concentrations increased drastically after the 1960s and reached the highest levels in the late 1990s. In addition, a significant positive correlation was observed between the concentrations of their predominant congeners, 1,2,3,4,6,7,8-HpBDF and BDE-209. These results indicate that main contamination sources of PBDFs were technical PBDE formulations, especially DecaBDE. In contrast, total PBDDs in the surface sediments were rather uniform in the whole area of the bay. Furthermore, in the sediment cores, PBDD levels showed marginal fluctuation over the past century, with the predominance of 2,7-/2,8-DiBDDs and 1,3,7-/1,3,8-TrBDDs in all the sediment layers. It is noteworthy that these PBDD congeners were also found in the sediment layers corresponding to the pre-industrial era, supporting their natural formation in the coastal environment (C) 2017 Elsevier B.V. All rights reserved.
  • Rumi Tanoue, Luigi Margiotta-Casaluci, Belinda Huerta, Tamsin J. Runnalls, Kei Nomiyama, Tatsuya Kunisue, Shinsuke Tanabe, John P. Sumpter
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 51 (21) 12825 - 12835 0013-936X 2017/11 [Peer-reviewed]
     Scientific journal 
    Recent species-extrapolation approaches to the prediction of the potential effects of pharmaceuticals present in the environment on wild fish are based on the assumption that pharmacokinetics and metabolism in humans and fish are comparable. To test this hypothesis, we exposed fathead minnows to the opiate pro-drug tramadol and examined uptake from the water into the blood and brain and the metabolism of the drug into its main metabolites. We found that plasma concentrations could be predicted reasonably accurately based on the lipophilicity of the drug once the pH of the water was taken into account. The concentrations of the drug and its main metabolites were higher in the brain than in the plasma, and the observed brain and plasma concentration ratios were within the range of values reported in mammalian species. This fish species was able to metabolize the pro-drug tramadol into the highly active metabolite O-desmethyl tramadol and the inactive metabolite N-desmethyl tramadol in a similar manner to that of mammals. However, we found that concentration ratios of O-desmethyl tramadol to tramadol were lower in the fish than values in most humans administered the drug. Our pharmacokinetic data of tramadol in fish help bridge the gap between widely available mammalian pharmacological data and potential effects on aquatic organisms and highlight the importance of understanding drug uptake and metabolism in fish to enable the full implementation of predictive toxicology approaches.
  • Chihiro Ishii, Shouta M. M. Nakayama, Yoshinori Ikenaka, Hokuto Nakata, Keisuke Saito, Yukiko Watanabe, Hazuki Mizukawa, Shinsuke Tanabe, Kei Nomiyama, Terutake Hayashi, Mayumi Ishizuka
    CHEMOSPHERE 186 367 - 373 0045-6535 2017/11 [Peer-reviewed]
     Scientific journal 
    Lead (Pb) poisoning is widespread among raptors and water birds. In Japan, fragments of Pb ammunition are still found in endangered eagles although more than 10 years have passed since legislation regarding use of Pb ammunition was introduced. This study was performed to investigate Pb exposure in raptors from various locations in Japan. We measured hepatic and renal Pb concentrations and hepatic Pb isotope ratios of Steller's sea eagles (Haliaeetus pelagicus), white-tailed sea eagles (Haliaeetus albicilla), golden eagles (Aquila chrysaetos), and 13 other species (total 177 individuals) that were found dead, as well as blood samples from three eagles found in a weakened state during 1993-2015 from Hokkaido (northern part), Honshu (the main island), and Shikoku (a southern island) of japan. In the present study in Hokkaido, one quarter of the sea eagles showed a high Pb concentration, suggesting exposure to abnormally high Pb levels and Pb poisoning. Pb isotope ratios indicated that endangered Steller's sea eagle and white-tailed sea eagle were poisoned by Pb ammunition that was used illegally in Hokkaido. In other areas of Japan, both surveillance and regulations were less extensive than in Hokkaido, but Pb poisoning in raptors was also noted. Therefore, Pb poisoning is still a serious problem in raptors in various areas of Japan due to accidental ingestion of materials containing Pb, especially Pb ammunition. (C) 2017 Published by Elsevier Ltd.
  • Akitoshi Goto, Nguyen Minh Tue, Masayuki Someya, Tomohiko Isobe, Shin Takahashi, Shinsuke Tanabe, Tatsuya Kunisue
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 51 (20) 11771 - 11779 0013-936X 2017/10 [Peer-reviewed]
     Scientific journal 
    In addition to unintentional formation of polychlorinated (PCDD/Fs), polybrominated (PBDD/Fs), and mixed halogenated (PXDD/Fs) dibenzo-p-dioxins/dibenzofurans during industrial activities, recent studies have shown that several PBDD and PXDD congeners can be produced by marine algal species from the coastal environment. However, multiple exposure status of anthropogenic and naturally derived dioxins in marine organisms remains unclear. The present study examined the occurrence, geographical distribution, and potential sources of PCDD/Fs, PBDD/Fs, and PXDD/Fs using mussels and brown algae collected in 2012 from Seto Inland Sea, Japan. The results showed the widespread occurrence of not only PCDD/Fs but also PBDDs and PXDDs in Seto Inland Sea. The geographical distribution pattern of PBDDs was similar to that of PXDDs, which were obviously different from that of PCDDs and PCDFs, and a significant positive correlation was observed between the levels of their predominant congeners, i.e., 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs. Interestingly, potential precursors of 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs, hydroxylated tetrabrominated diphenyl ethers (6-HO-BDE-47 and 2'-HO-BDE-68) and their mixed halogenated analogue (HO-TrBMoCDE), were also identified in the mussel and brown alga samples collected at the same site, by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC X GCToFMS) analyses. It is noteworthy that residue levels of 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs in the mussel were 30 times higher than those in the brown alga, suggesting the bioaccumulation of these natural dioxins.
  • Shin Takahashi, Nguyen Minh Tue, Chika Takayanagi, Le Huu Tuyen, Go Suzuki, Hidenori Matsukami, Pham Hung Viet, Tatsuya Kunisue, Shinsuke Tanabe
    JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT 19 (4) 1333 - 1341 1438-4957 2017/10 [Peer-reviewed]
     Scientific journal 
    Floor dusts from Vietnamese end-of-life vehicle (ELV)-processing households were investigated to elucidate the contamination levels and exposure risk of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and dioxin-related compounds (DRCs). The concentrations were in order of PBDEs (260-11,000, median 280 ng/g overall) > PCBs (19-2200, median 140 ng/g) > dioxin-like PCBs (8.8-450, median 22 ng/g) >> polybrominated dibenzo-p-dioxin/dibenzofurans (PBDD/Fs, 2000-28,000, median 8500 pg/g) > polychlorinated dibenzo-p-dioxin/dibenzofurans (PCDD/Fs, 440-4100, median 1800 pg/g) > MoBPCDD/Fs (1.9-1200, median 250 pg/g). Concentrations of PCBs and DRCs were higher than those reported for Vietnamese urban houses, indicating ELV processing as a significant source of these contaminants. Higher concentrations of PCBs relative to PBDEs suggest the abundance of old electrical capacitors/transformers in ELVs. The PBDD/F and PCDD/F profiles were indicative of DecaBDE-containing materials and combustion sources, respectively. PBDFs, PCDFs and DL-PCBs were the most important dioxin-like toxic equivalent (TEQ) contributors. The estimated PCB and TEQ intake doses from dust ingestion approached or exceeded the reference doses for children living in some ELV-processing households, indicating potential health risk. More comprehensive risk assessment of the exposure to PCBs and DRCs is required for residents of informal ELV recycling sites.
  • Nguyen Minh Tue, Akitoshi Goto, Shin Takahashi, Takaaki Itai, Kwadwo Ansong Asante, Kei Nomiyama, Shinsuke Tanabe, Tatsuya Kunisue
    JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT 19 (4) 1324 - 1332 1438-4957 2017/10 [Peer-reviewed]
     Scientific journal 
    Detailed composition of chlorinated and brominated polycyclic aromatic hydrocarbons (Cl-PAHs and Br-PAHs) generated during informal recycling of e-waste and their toxic relevance are still poorly understood. This study investigated the occurrence of Cl-PAHs and Br-PAHs in surface soil samples from the Agbogbloshie e-waste recycling site (Accra, Ghana) using quantitative gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional GC-time-of-flight mass spectrometry (GC x GC-ToFMS) profiling. The results of GC-MS analysis showed elevated concentrations in open e-waste burning areas (160-220 and 19-46 ng/g dry weight for Cl- and Br-PAHs, respectively) with substantial contribution from unidentified compounds (respectively, more than 36 and 70%, based on the total areas of potential peaks). Cl- and Br-PAHs from e-waste burning had a distinctive composition dominated by ring-ring compounds. Several homologue groups not monitored with GC-MS were found using GC x GC-ToFMS: PAHs with up to 5 Cl or 3Br, mixed halogenated PAHs and chlorinated methylPAHs. The dioxin-like toxic equivalents of the identified Cl-/Br-PAHs in soils, estimated from their in vitro AhR agonist potencies relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin, were much lower than the range reported for chlorinated and brominated dioxins. However, the toxicity of the unidentified halogenated PAHs remained unclear.
  • Hazuki Mizukawa, Kei Nomiyama, Susumu Nakatsu, Miyuki Yamamoto, Mayumi Ishizuka, Yoshinori Ikenaka, Shouta M. M. Nakayama, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 51 (19) 11354 - 11362 0013-936X 2017/10 [Peer-reviewed]
     Scientific journal 
    Present study determined concentrations and residue patterns of bromophenols (BPhs) in whole blood samples of pet cats and pet dogs collected from veterinary hospitals in Japan. BPhs concentrations were higher in cat blood than in dog blood, with statistically insignificant differences (p = 0.07). Among the congeners, 2,4,6-tribromophenol (TBPh) constituted the majority of BPhs (>90%) detected in both species. Analysis of commercial pet food to estimate exposure routes showed that the most abundant congener in all pet food samples was 2,4,6-TBPh, accounting for >99% of total BPhs. This profile is quite similar to the blood samples of the pets, suggesting that diet might be an important exposure route for BPhs in pets. After incubation in polybrominated diphenyl ether (PBDE) mixtures (BDE-47, BDE-99 and BDE-209), 2,4,5-TBPh was found in dog liver microsomes but not in cat liver microsomes, implying species-specific metabolic capacities for PBDEs. Formation of 2,4,5-TBPh occurred by hydroxylation at the 1' carbon atom of the ether bond of BDE-99 is similar to human study reported previously. Hydroxylated PBDEs were not detected in cats or dogs; therefore, diphenyl ether bond cleavage of PBDEs can also be an important metabolic pathway for BPhs formation in cats and dogs.
  • Takamitsu Kondo, Yoshinori Ikenaka, Shouta M. M. Nakayama, Yusuke K. Kawai, Hazuki Mizukawa, Yoko Mitani, Kei Nomiyama, Shinsuke Tanabe, Mayumi Ishizuka
    TOXICOLOGICAL SCIENCES 158 (1) 90 - 100 1096-6080 2017/07 [Peer-reviewed]
     Scientific journal 
    UDP-glucuronosyltransferases (UGTs) are among the most important xenobiotic metabolizing enzymes that conjugate a wide range of chemicals. Previous studies showed that Felidae and Pinnipedia species have very low UGT activities toward some phenolic compounds because of the UGT1A6 pseudogene and small numbers of UGT1A isozymes. In addition to the UGT1As, UGT2Bs isozymes also conjugate various endogenous (eg, estrogens, androgens, and bile acids) and exogenous compounds (opioids, non-steroidal anti-inflammatory drugs, and environmental pollutants). However UGT2B activity and genetic background are unknown in carnivore species. Therefore, this study was performed to elucidate the species differences of UGT2Bs. Using typical substrates for UGT2Bs, UGT activity was measured in vitro. In addition, UGT2B genetic features are analyzed in silico. Results of UGT activity measurement indicate marked species differences between dogs and other carnivores (cats, Northern fur seals, Steller sea lions, Harbor seals, and Caspian seals). Dogs have very high V-max/K-m toward estradiol (17-glucuronide), estrone, lorazepam, oxazepam, and temazepam. Conversely, cats and pinniped species (especially Caspian seals and Harbor seals) have very low activities toward these substrates. The results of genetic synteny analysis indicate that Felidae and pinniped species have very small numbers of UGT2B isozymes (one or none) compared with dogs, rodents, and humans. Furthermore, Felidae species have the same nonsense mutation in UGT2B, which suggests that Felidae UGT2B31-like is also a pseudogene in addition to UGT1A6. These findings of lower activity of UGT2B suggest that Felidae and some pinniped species have very low UGT activity toward a wide range of chemicals. These results are important for Felidae and Pinnipedia species that are frequently exposed to drugs and environmental pollutants.
  • Mari Ochiai, Kei Nomiyama, Tomohiko Isobe, Tadasu K. Yamada, Yuko Tajima, Ayaka Matsuda, Akira Shiozaki, Takashi Matsuishi, Masao Amano, Hisato Iwata, Shinsuke Tanabe
    MARINE ENVIRONMENTAL RESEARCH 128 124 - 132 0141-1136 2017/07 [Peer-reviewed]
     Scientific journal 
    This study investigated the accumulation of polybrominated diphenyl ethers (PBDEs) and their hydroxylated and methoxylated analogues (OH-PBDEs and MeO-PBDEs) in the blood of harbor porpoises, Dall's porpoises, and finless porpoises stranded or bycaught in Japanese coastal waters and in the North Pacific Ocean. Moreover, we suggested the origins of these contaminants and the factors affecting their pattern of accumulation. Levels of PBDEs in Dall's porpoises were one order of magnitude greater than those in the other species. OH-PBDE and MeO-PBDE levels were comparable to those of PBDEs. However, no correlation was found between the levels of OH-PBDEs and PBDEs, whereas a strong correlation was found between that of OH-PBDEs and MeO-PBDEs (p < 0.001). 6OH-BDE47, reported compound bio-synthesized by marine low-trophic level organisms, was the dominant congener. These results suggest that PBDEs found in these porpoise species derive from flame retardants, but OH-PBDEs and MeO-PBDEs are mainly of natural origins. (C) 2016 Elsevier Ltd. All rights reserved.
  • Chiya Nishimura, Yuichi Horii, Shuhei Tanaka, Kwadwo Ansong Asante, Florencio Ballesteros, Pham Hung Viet, Takaaki Itai, Hidetaka Takigami, Shinsuke Tanabe, Takashi Fujimori
    ENVIRONMENTAL POLLUTION 225 252 - 260 0269-7491 2017/06 [Peer-reviewed]
     Scientific journal 
    We conducted this study to assess the occurrence, profiles, and toxicity of chlorinated polycyclic aromatic hydrocarbons (CI-PAHs) and brominated polycyclic aromatic hydrocarbons (Br-PAHs) in e-waste open burning soils (EOBS). In this study, concentrations of 15 PAHs, 26 CI-PAHs and 14 Br-PAHs were analyzed in EOBS samples. We found that e-waste open burning is an important emission source of Cl-PAHs and Br-PAHs as well as PAHs. Concentrations of total CI-PAHs and Br-PAHs in e-waste open burning soil samples ranged from 21 to 2800 ng/g and from 5.8 to 520 ng/g, respectively. Compared with previous studies, the mean of total CI-PAH concentrations of the EOBS samples in this study was higher than that of electronic shredder waste, that of bottom ash, and comparable to fly ash from waste incinerators in Korea and Japan. The mean of total Br-PAH concentrations of the EOBS samples was generally three to four orders of magnitude higher than those in incinerator bottom ash and comparable to incinerator fly ash, although the number of Br-PAH congeners measured differed among studies. We also found that the CI-PAH and Br-PAH profiles were similar among all e-waste open burning soil samples but differed from those in waste incinerator fly ash. The profiles and principal component analysis results suggested a unique mechanism of CI-PAH and Br-PAH formation in EOBS. In addition, the CI-PAHs and Br-PAHs showed high toxicities equivalent to PCDD/Fs measured in same EOBS samples when calculated based on their relative potencies to benzo[a]pyrene. Along with chlorinated and brominated dioxins and PAHs, CI-PAHs and Br-PAHs are important environmental pollutants to investigate in EOBS. (C) 2016 Elsevier Ltd. All rights reserved.
  • Kei Nomiyama, Kohki Takaguchi, Hazuki Mizukawa, Yasuko Nagano, Tomoko Oshihoi, Susumu Nakatsu, Tatsuya Kunisue, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 51 (10) 5811 - 5819 0013-936X 2017/05 [Peer-reviewed]
     Scientific journal 
    The adverse effects of elevated polybrominated diphenyl ether (PBDE) levels, reported in the blood of domestic dogs and cats, are considered to be of great concern. However, the tissue distribution of PBDEs and their derivatives in these animals is poorly understood. This study determined the concentrations and profiles of PBDEs, hydroxylated PBDEs (OH-PBDEs), methoxylated PBDEs (MeO-PBDEs), and 2,4,6-tribromophenol (2,4,6-tri-BPh) in the blood, livers, bile, and brains of dogs and cats in Japan. Higher tissue concentrations of PBDEs were found in cats, with the dominant congener being BDE209. BDE207 was also predominant in cat tissues, indicating that BDE207 was formed via BDE209 debromination. BDE47 was the dominant congener in dog bile, implying a species-specific excretory capacity of the liver. OH-PBDE and MeO-PBDE concentrations were several orders of magnitude higher in cat tissues, with the dominant congener being 6OH-BDE47, possibly owing to their intake of naturally occurring MeO-PBDEs in food, MeO-PBDE demethylation in the liver, and lack of UDP-glucuronosyltransferase, UGT1A6. Relatively high concentrations of BDE209, BDE207, 6OH-BDE47, 2'MeO-BDE68, and 2,4,6-tri-BPh were found in cat brains, suggesting a passage through the blood brain barrier. Thus, cats in Japan might be at a high risk from PBDEs and their derivatives, particularly BDE209 and 6OH-BDE47.
  • Hidenori Matsukami, Go Suzuki, Masayuki Someya, Natsuyo Uchida, Nguyen Minh Tue, Le Huu Tuyen, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe, Hidetaka Takigami
    CHEMOSPHERE 167 291 - 299 0045-6535 2017/01 [Peer-reviewed]
     Scientific journal 
    We investigated the concentrations of polybrominated diphenyl ethers (PBDEs) and alternative flame retardants (FRs) in environmental samples collected, in January 2012, 2013, and 2014 from an electronic waste-processing area in northern Vietnam. During the study period, PBDE and alternative FR concentrations in soils around the electronic waste-processing workshops ranged from 37 to 9200 ng g(-1) dry weight (dw) and from 35 to 24,000 ng g(-1) dw; the concentrations in soils around the open-burning sites ranged from 1.6 to 62 ng g(-1) dw and from <4 to 1900 ng g(-1) dw; and the concentrations in river sediments around the workshops ranged from 100 to 3800 ng g(-1) dw and from 23 to 6800 ng g(-1) dw, respectively. Over the course of study period, we observed significant decreases in concentrations of PBDEs and significant increases in concentrations of alternative FRs, particularly Dechlorane Plus isomers and oligomeric organophosphorus FRs (o-PFRs) in both soils and sediments around the workshops. We also report information on concentrations and environmental emissions of o-PFRs and their low molecular-weight impurities in the same soils and sediments. The detection of o-PFR impurities around the workshops and the open-burning sites highlights an enhanced breakdown of o-PFRs probably due to weathering during open storage and high temperature attained during the burning of electronic wastes. (C) 2016 Elsevier Ltd. All rights reserved.
  • Ana C. A. Sousa, Sonia D. Coelho, M. Ramiro Pastorinho, Luis Taborda-Barata, Antonio J. A. Nogueira, Tomohiko Isobe, Tatsuya Kunisue, Shin Takahashi, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 574 19 - 23 0048-9697 2017/01 [Peer-reviewed]
     Scientific journal 
    Organotin compounds (OTs) are ubiquitous contaminants with a broad range of applications ranging from biocides and pesticides to catalysts for the production of polyurethane foams and silicones. The deleterious effects of some OTs (particularly tributyltin - TBT) upon wildlife and experimental animals are well documented and include endocrine disruption, immunotoxicity, neurotoxicity, genotoxicity and metabolic dysfunction in which obesity is included. However, virtually no data on the current human exposure levels is available. In order to bridge this gap, we quantified for the first time the levels of OTs in duplicate diet samples from members of the University of Aveiro in Portugal. OTs were detected in 32% of the 28 diet samples analyzed, at relatively low levels. TBT and monobutyltin were detected only in two samples and dibutyltin was detectable in three samples. Dioctyltin was quantified in four samples and monooctyltin in three samples. Phenyltins were below the detection limit in all the diet samples analyzed. Overall, for the vast majority of the samples (89%), the estimated daily intakes (EDI) of organotins through food were much lower than the established tolerable daily intakes (TDI). Hence, for the majority of the participants the risk associated with food ingestion is low. (C) 2016 Elsevier B.V. All rights reserved.
  • Sonia D. Coelho, M. Ramiro Pastorinho, Takaaki Itai, Tomohiko Isobe, Tatsuya Kunisue, Antonio J. A. Nogueira, Shinsuke Tanabe, Ana C. A. Sousa
    SCIENCE OF THE TOTAL ENVIRONMENT 573 603 - 607 0048-9697 2016/12 [Peer-reviewed]
     Scientific journal 
    Lead is a naturally occurring element that with the advent of the industrial era became a serious environmental and public health issue. Leaded gasoline, lead based paints, use of lead in plumbing and water pipes, ceramics with lead-containing glazes and tobacco smoke are potential sources of lead exposure for humans. Despite these multiple sources, food is still considered the most important one for the general non-smoking population. Hence, in the present study, the dietary intake of lead was determined in duplicate diet samples provided by 30 participants working or studying at University of Aveiro, Portugal. Pb was detected in all the analysed samples with values ranging between 0.009 and 0.10 mg kg(-1) ww which correspond to estimated daily intakes between 022 and 3.5 mu g kg-bw(-1) day(-1). Risk estimations disclose that at least 33% and 26.7% of the participants might suffer cardiovascular and nephrotoxic effects, respectively. (C) 2016 Elsevier B.V. All rights reserved.
  • Takashi Fujimori, Akifumi Eguchi, Tetsuro Agusa, Nguyen Minh Tue, Go Suzuki, Shin Takahashi, Pham Hung Viet, Shinsuke Tanabe, Hidetaka Takigami
    JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT 18 (4) 599 - 607 1438-4957 2016/09 [Peer-reviewed]
     Scientific journal 
    Used lead-acid battery (ULAB) recycling has caused numerous health and environmental issues in developing countries. Surface soil pollution from ULAB recycling activities has been linked with elevated levels of lead in human blood. We measured surface soil lead in and surrounding the ULAB recycling village of Hung Yen in northern Vietnam in 2011, 2013, and 2014. The data were analyzed statistically and discussed with respect to distance from the contamination source, year of measurement, contamination pathway, and countermeasures against the contamination. Transportation routes from the smelter or collection site displayed the greatest concentration of surface soil lead (median 6400-10,000 mg/kg). Surface soil lead decreased significantly with distance along the road from the ULAB recycling site, although such a decrease was not observed for rice fields, agricultural roads, or garden soil. Re-suspension and adherence by traffic were identified as key pollution pathways. Distance from the source, covering of the surface of roads, construction of walls, and position relative to the source were shown to be the most effective factors in the reduction of surface soil lead pollution. Application of a combination of these measures should result in improvement in the health of residents.
  • Wang, Q, Miyake, Y, Amagai, T, Matsukami, H, Tue, N. M, Takahashi, S, Tanabe, S, Viet, P. H, Takigami, H
    Journal of Water and Environment Technology 14 (3) 166 - 176 2016/06 [Peer-reviewed]
  • Go Suzuki, Masayuki Someya, Hidenori Matsukami, Nguyen Minh Tue, Natsuyo Uchida, Le Huu Tuyen, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe, Abraham Brouwer, Hidetaka Takigami
    Emerging Contaminants 2 (2) 98 - 108 2405-6642 2016/06 [Peer-reviewed]
     Scientific journal 
    The management of electronic waste (e-waste), which can be a source of both useful materials and toxic substances, depending on the processing method, is important for promoting material cycling. In this study, we used the dioxin-responsive chemical-activated luciferase gene expression (DR-CALUX) assay combined with gas chromatography–high-resolution mass spectrometry to evaluate the levels of dioxin-like compounds in surface soils and river sediments collected in and around an e-waste-processing village in northern Vietnam. The WHO-TEQs (Toxic equivalents) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), coplanar polychlorinated biphenyls (Co-PCBs), and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in soils collected in January 2012 ranged from 0.29 to 310 pg/g (median 2.9 pg/g, n = 32), and the WHO-TEQs in sediments ranged from 0.96 to 58 pg/g (median 4.4 pg/g, n = 8). Dioxin-like activities (CALUX-TEQs [2,3,7,8-TCDD equivalent]) in soils collected in January 2012, 2013, and 2014 ranged from < 30 to 4300 pg/g (median < 30 pg/g, n = 96), and the activities in sediments ranged from < 30 to 4000 pg/g (median 33 pg/g, n = 24). Dioxin-like compounds accumulated in samples collected around e-waste-processing areas such as open-burning sites and e-waste-processing workshops, and the compounds may be transported from their sources to surrounding areas over the course of several years. Some of the CALUX-TEQs, but not WHO-TEQs, values were higher than the maximum acceptable WHO-TEQs promulgated by various authorities, indicating that all dioxin-like compounds should be evaluated in samples collected from e-waste-processing areas. Our findings suggest that open burning and open storage of e-waste should be prohibited and that wastewater treatment should be implemented at each workshop to reduce contamination by dioxin-like compounds from e-waste.
  • Hidenori Matsukami, Go Suzuki, Nguyen Minh Tue, Le Huu Tuyen, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe, Hidetaka Takigami
    Emerging Contaminants 2 (2) 89 - 97 2405-6642 2016/06 [Peer-reviewed]
     Scientific journal 
    Using electrospray ionization tandem mass spectrometry combined with liquid chromatography (LC), a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants (m-PFRs) and three oligomeric organophosphorus flame retardants (o-PFRs) in fish muscle samples. The optimization and validation experiments indicate that the developed method can determine accurately the concentrations of analytes in fish muscle samples. The recoveries of analytes in fish muscle samples were in the range of 74–105%. The coefficients of variation of the concentrations of analytes in fish muscle samples were 0.6–8.9%. The concentrations of analytes in procedural blanks were below the limit of quantification (LOQ) values. Furthermore, the developed method was applied to the analysis of m-PFRs and o-PFRs in the muscle samples of tilapias collected from an electronic waste (e-waste) processing area in northern Vietnam. The concentrations of m-PFRs such as tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP), and triphenyl phosphate (TPHP) were dominant among the investigated m-PFRs. The respective concentrations of TCEP, TCIPP, and TPHP were up to 160, 300, and 230 ng g−1 lipid weight, respectively, whereas those of o-PFRs were up to 10 ng g−1 lipid weight. The results of this study indicate lower accumulation potential of o-PFRs compared with m-PFRs for the first time.
  • Masayuki Someya, Go Suzuki, Alin C. Ionas, Nguyen Minh Tue, Fuchao Xu, Hidenori Matsukami, Adrian Covaci, Le Huu Tuyen, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe, Hidetaka Takigami
    Emerging Contaminants 2 (2) 58 - 65 2405-6642 2016/06 [Peer-reviewed]
     Scientific journal 
    This study investigated the contamination status of 21 emerging flame retardants (FRs) in soils (n = 32) and river sediments (n = 8) from an e-waste recycling (EWR) site in the northern part of Vietnam. Among analyzed FRs, higher levels of decabromodiphenyl ethane (DBDPE) (ND–4200 ng/g dw), 1,2-bis-(2,4,6-tribromophenoxy)ethane (BTBPE) (ND–350 ng/g dw) and Dechlorane Plus isomers (DPs) (ND–65 ng/g dw) were found in soils near EWR workshops and open burning places. The highest concentrations of DBDPE (20 ng/g dw), BTBPE (5.7 ng/g dw) and DPs (6.7 ng/g dw) were also detected in sediments collected from the middle of the EWR site. The levels decreased concomitantly with increasing distance from the EWR site. These results indicate that these FRs were released to the surrounding environment from improper recycling activities, such as manual dismantling of devices and open burning of e-wastes. Moreover, the estimated daily intakes of those FRs via soil ingestion were approximately ten times higher for children than adults. To our knowledge, this is a first comprehensive study on characterization of soil and sediment contamination by a series of emerging FRs at an EWR site in Vietnam.
  • Junko Fujihara, Toshihiro Yasuda, Hisato Iwata, Shinsuke Tanabe, Haruo Takeshita
    ARCHIVES OF TOXICOLOGY 90 (4) 1009 - 1012 0340-5761 2016/04 [Peer-reviewed]
     Scientific journal 
    The associations of four single nucleotide polymorphisms (p.Arg194Trp, p.Arg280His, p.Pro206Pro, and p.Arg399Gln) in X-ray repair cross-complementing group 1 with urinary arsenic metabolites and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were investigated in a Vietnamese population (n = 100). Individuals with genotype AA in p.Pro206Pro showed significantly higher urinary monomethylarsonic acid (MMA(V)) and lower dimethylarsinic acid (DMA(V))/MMA(V) ratio than genotype AG. As for p.Arg399Gln, both Arg/Arg homozygous subjects and Arg/Gln heterozygous individuals showed a significantly higher urinary inorganic As percentage and lower 8-OHdG concentrations than Gln/Gln homozygous. Our results suggested that Arg399Gln is a functional SNP that may be related to DNA repair activity.
  • Paula Sanchez-Marin, Isabel B. Oliveira, Ana C. A. Sousa, Shin Takahashi, Shinsuke Tanabe, Susana Galante-Oliveira
    JOURNAL OF MOLLUSCAN STUDIES 82 144 - 153 0260-1230 2016/02 [Peer-reviewed]
     Scientific journal 
    Male and female aphally in Nucella lapillus has been reported in some populations from the northeastern Atlantic coast, namely in localized areas in southeastern England, northwestern France and northwestern Spain. This occurrence has been associated with Dumpton syndrome (DS), a genetic anomaly that causes under-development of the male genital tract and confers resistance to the masculinizing effects of tributyltin (TBT), i.e. to the development of imposex (superimposition of male sexual characters on neogastropod females). In an effort to elucidate the potential occurrence of DS among Portuguese populations of N. lapillus, data obtained from imposex levels monitoring campaigns performed from 2000 to 2006, during which female aphally was frequently observed, were compiled and analysed. Several characteristics associated with a demasculinizing syndrome were observed in two sampling sites near the port of Lisbon: high frequency of female aphally, undersized penises in males and lower incidence of TBT-induced imposex together with the simultaneous presence of females with contrasting vas deferens sequence values (0 and 4) at the same site. Despite the similarities with DS, the relatively lower levels of TBT pollution recorded in Portugal in comparison with other European coastal areas, and the fact that male aphally was only occasionally found, are reasons to suggest that other nongenetic causes are potentially involved in the development of female aphally in this geographical area. Nevertheless, a lower sensitivity to TBT of Portuguese N. lapillus populations that present a high frequency of aphally is apparent and this hypothetical resistance is discussed.
  • Takashi Fujimori, Takaaki Itai, Akitoshi Goto, Kwadwo A. Asante, Masanari Otsuka, Shin Takahashi, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 209 155 - 163 0269-7491 2016/02 [Peer-reviewed]
     Scientific journal 
    Open burning of electronic waste (e-waste) releases various metals and organohalogen compounds in the environment. Here we investigated the interplay of metals (Cu, Pb, Zn, Fe, Co, and Sr) and bromine (Br) in the formation of dioxin-related compounds (DRCs), including polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs), as well as non-regulated DRCs such as polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) and their monobrominated PCDD/Fs in soils sampled from open burning e-waste sites at Agbogbloshie in Accra, Ghana. The predominant DRCs were PBDFs, PCDFs, PCDD5, and DL-PCBs. Statistical analyzes, X-ray absorption spectroscopy, and the PCDF/PCDD ratio suggested possible formation paths of PCDD/Fs and DL-PCBs by catalytic behaviors of copper chlorides (CuCI, CuCl2, and Cu-2(OH)(3)Cl) and thermal breakdown of polyvinyl chloride. Predominant formation of brominated furans may be derived from electron transfer from intermediates of PBDE to copper, Cu(II) -> Cu(I). Lead chloride also contributed to generate DRCs and may become highly bioaccessible through the open burning of e-waste. The main zinc species (ZnCl2 and ZnS) suggested a possible relationship to generate DRCs and specific zinc source such as tire burning. Cu, Pb, Zn, and Br contained in various e-wastes, wires/cables, plastics, and tires strongly influenced generation of many DRCs. (C) 2015 Elsevier Ltd. All rights reserved.
  • Tashiro, Y, Goto, A, Kunisue, T, Kurahashi, T, Tanabe, S
    Journal of Environmental Chemistry 26 (3) 115 - 122 2016 [Peer-reviewed]
  • Coelho, S{\'o}nia D, Sousa, Ana CA, Isobe, Tomohiko, Kunisue, Tatsuya, Nogueira, Ant{\'o}nio JA, Tanabe, Shinsuke
    Chemosphere 160 89 - 94 0045-6535 2016 [Peer-reviewed]
     Scientific journal
  • Coelho, S{\'o}nia D, Sousa, Ana CA, Isobe, Tomohiko, Kim, Joon-Woo, Kunisue, Tatsuya, Nogueira, Ant{\'o}nio JA, Tanabe, Shinsuke
    Science of The Total Environment 569 442 - 449 0048-9697 2016 [Peer-reviewed]
     Scientific journal
  • Hazuki Mizukawa, Kei Nomiyama, Susumu Nakatsu, Hisato Iwata, Jean Yoo, Akira Kubota, Miyuki Yamamoto, Mayumi Ishizuka, Yoshinori Ikenaka, Shouta M. M. Nakayama, Tatsuya Kunisue, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 50 (1) 444 - 452 0013-936X 2016/01 [Peer-reviewed]
     Scientific journal 
    There are growing concerns about the increase in hyperthyroidism in pet cats due to exposure to organo-halogen contaminants and their hydroxylated metabolites. This study investigated the blood contaminants polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) and their hydroxylated and methoxylated derivatives (OH-PCBs, OH-PBDEs, and MeO-PBDEs), in pet dogs and cats. We also measured the residue levels of these compounds in commercially available pet foods. Chemical analyses of PCBs and OH-PCBs showed that the OH-PCB levels were 1 to 2 orders of magnitude lower in cat and dog food products than in their blood, suggesting that the origin of OH-PCBs in pet dogs and cats is PCBs ingested with their food. The major congeners of OH-/MeO-PBDEs identified in both pet food products and blood were natural products (60H-/MeO-BDE47 and 2'OH-/MeO-BDE68) from marine organisms. In particular, higher concentrations of 60H-BDE47 than 2'OH-BDE68 and two MeO-PBDE congeners were observed in the cat blood, although MeO-BDEs were dominant in cat foods, suggesting the efficient biotransformation of 60H-BDE47 from 6MeO-BDE47 in cats. We performed in vitro demethylation experiments to confirm the biotransformation of MeO-PBDEs to OH-PBDEs using liver microsomes. The results showed that 6MeO-BDE47 and 2'MeO-BDE68 were demethylated to 60H-BDE47 and 2'OH-BDE68 in both animals, whereas no hydroxylated metabolite from BDE47 was detected. The present study suggests that pet cats are exposed to MeO-PBDEs through cat food products containing fish flavors and that the OH-PBDEs in cat blood are derived from the CYP-dependent demethylation of naturally occurring MeO-PBDE congeners, not from the hydroxylation of PBDEs.
  • Nguyen Minh Tue, Akitoshi Goto, Shin Takahashi, Takaaki Itai, Kwadwo Ansong Asante, Tatsuya Kunisue, Shinsuke Tanabe
    JOURNAL OF HAZARDOUS MATERIALS 302 151 - 157 0304-3894 2016/01 [Peer-reviewed]
     Scientific journal 
    Although complex mixtures of dioxin-related compounds (DRCs) can be released from informal e-waste recycling, DRC contamination in African e-waste recycling sites has not been investigated. This study examined the concentrations of DRCs including chlorinated, brominated, mixed halogenated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs, PBDD/Fs, PXDD/Fs) and dioxin-like polychlorinated biphenyls (DLPCBs) in surface soil samples from the Agbogbloshie e-waste recycling site in Ghana. PCDD/F and PBDD/F concentrations in open burning areas (18-520 and 83-3800 ng/g dry, respectively) were among the highest reported in soils from informal e-waste sites. The concentrations of PCDFs and PBDFs were higher than those of the respective dibenzo-p-dioxins, suggesting combustion and PBDE-containing plastics as principal sources. PXDFs were found as more abundant than PCDFs, and higher brominated analogues occurred at higher concentrations. The median total WHO toxic equivalent (TEOJ concentration in open burning soils was 7 times higher than the U.S. action level (1000 pg/g), with TEQ contributors in the order of PBDFs >> PCDD/Fs > PXDFs. DRC emission to soils over the e-waste site as of 2010 was estimated, from surface soil lightness based on the correlations between concentrations and lightness, at 200 mg (95% confidence interval 93-540 mg) WHO-TEQ over three years. People living in Agbogbloshie are potentially exposed to high levels of not only chlorinated but also brominated DRCs, and human health implications need to be assessed in future studies. (C) 2015 Elsevier B.V. All rights reserved.
  • Jean Yoo, Masashi Hirano, Hazuki Mizukawa, Kei Nomiyama, Tetsuro Agusa, Eun-Young Kim, Shinsuke Tanabe, Hisato Iwata
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 49 (24) 14588 - 14596 0013-936X 2015/12 [Peer-reviewed]
     Scientific journal 
    The aim of this study was to understand the cytochrome P450 (CYP)-dependent metabolic pathway and potency of polychlorinated biphenyls (PCBs) in the Baikal seal (Pusa sibirica). In vitro metabolism of 62 PCB congener mixtures was investigated by using liver microsomes of this species. A decreased ratio of over 20% was observed for CB3, CB4, CB8, CB15, CB19, CB22, CB37, CB54, CB77, and CB105, suggesting the preferential metabolism of low-chlorinated PCBs by CYPs. The highly activated metabolic pathways in Baikal seals that were predicted from the decreased PCBs and detected hydroxylated PCBs (OH-PCBs) were CB22 to 4'OH-CB20 and CB77 to 4'OH-CB79. The total amount of OH-PCBs detected as identified and unidentified congeners accounted for only a 3.8 +/- 1.7 mol % of loaded PCBs, indicating many unknown PCB metabolic pathways. To explore factors involved in CYP-dependent PCB metabolism, we examined the relationships among the structural and physicochemical properties of PCBs, the in silica PCB-CYP docking parameters, and the in vitro PCB decreased ratios by principal component analysis. Statistical analysis showed that the decreased PCB ratio was at least partly accounted for by the substituted chlorine number of PCBs and the distance from the CI-unsubstituted carbon of docked PCBs to the heme Fe in CYP2A and 2B.
  • Mayu Kakehi, Yoshinori Ikenaka, Shouta M. M. Nakayama, Yusuke K. Kawai, Kensuke P. Watanabe, Hazuki Mizukawa, Kei Nomiyama, Shinsuke Tanabe, Mayumi Ishizuka
    TOXICOLOGICAL SCIENCES 147 (2) 360 - 369 1096-6080 2015/10 [Peer-reviewed]
     Scientific journal 
    There are various interspecies differences in xenobiotic-metabolizing enzymes. It is known that cats show slow glucuronidation of drugs such as acetaminophen and strong side effects due to the UGT1A6 pseudogene. Recently, the UGT1A6 pseudogene was found in the Northern elephant seal and Otariidae was suggested to be UGT1A6-deficient. From the results of measurements of uridine diphosphate-glucuronosyltransferase (UGT) activity using liver microsomes, the Steller sea lion, Northern fur seal, and Caspian seal showed UGT activity toward 1-hydroxypyrene and acetaminophen as low as in cats, which was significantly lower than in rat and dog. Furthermore, UGT1A6 pseudogenes were found in Steller sea lion and Northern fur seal, and all Otariidae species were suggested to have the UGT1A6 pseudogene. The UGT1 family genes appear to have undergone birth-and-death evolution based on a phylogenetic and synteny analysis of the UGT1 family in mammals including Carnivora. UGT1A2-1A5 and UGT1A7-1A10 are paralogous genes to UGT1A1 and UGTA6, respectively, and their numbers were lower in cat, ferret and Pacific walrus than in human, rat, and dog. Felidae and Pinnipedia, which are less exposed to natural xenobiotics such as plant-derived toxins due to their carnivorous diet, have experienced fewer gene duplications of xenobiotic-metabolizing UGT genes, and even possess UGT1A6 pseudogenes. Artificial environmental pollutants and drugs conjugated by UGT are increasing dramatically, and their elimination to the environment can be of great consequence to cat and Pinnipedia species, whose low xenobiotic glucuronidation capacity makes them highly sensitive to these compounds.
  • Kentaro Misaki, Go Suzuki, Nguyen Minh Tue, Shin Takahashi, Masayuki Someya, Hidetaka Takigami, Yuko Tajima, Tadasu K. Yamada, Masao Amano, Tomohiko Isobe, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 49 (19) 11840 - 11848 0013-936X 2015/10 [Peer-reviewed]
     Scientific journal 
    Sulfuric acid-treated liver extracts of representative high-trophic level Japanese animals were analyzed by toxic identification and evaluation (TIE) with chemically activated luciferase expression (CALUX) and chemical analysis to elucidate androgen receptor (AR) antagonistic activities and potential contributions of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The activities were detected in striped dolphins (n = 5), Stejneger's beaked whales (n = 6), golden eagle (n = 1), and Steller's sea eagle (n = 1) with CALUX-flutamide equivalents (FluEQs) as follow: 38 (20-52), 47 (21-96), 5.0, and 80 mu g FluEQ/g-lipid, respectively. The AR antagonism was detected in limited number of specimens at lower levels for finless porpoise, raccoon dog, and common cormorant. Theoretical activities (Theo-FluEQs) were calculated using the concentration of OCPs and PCBs and their IC25-based relative potency (REP) values. These total contribution to CALUX-FluEQ was 126%, 84%, 53%, 55%, and 44% for striped dolphin, Steller's sea eagle, Stejneger's beaked whale, finless porpoise, and golden eagle, respectively, and the main contributor was p,p'-DDE. However, most of the activities for raccoon dog (7.6%) and common cormorant (17%) could not be explained by OCPs and PCBs. This suggests other unknown compounds could function as AR antagonists in these terrestrial species.
  • Rumi Tanoue, Kei Nomiyama, Haruna Nakamura, Joon-Woo Kim, Tomohiko Isobe, Ryota Shinohara, Tatsuya Kunisue, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 49 (19) 11649 - 11658 0013-936X 2015/10 [Peer-reviewed]
     Scientific journal 
    A fish plasma model (FPM) has been proposed as a screening technique to prioritize potential hazardous pharmaceuticals to wild fish. However, this approach does not account for inter- or intraspecies variability of pharmacokinetic and pharmacodynamic parameters. The present study elucidated the uptake potency (from ambient water), tissue distribution, and biological risk of 20 pharmaceutical and personal care product (PPCP) residues in wild cyprinoid fish inhabiting treated-wastewater-impacted streams. In order to clarify the uncertainty of the FPM for PPCPs, we compared the plasma bioaccumulation factor in the field (BAF(plasma) = measured fish plasma/ambient water concentration ratio) with the predicted plasma bioconcentration factor (BCFplasma = fish plasma predicted by use of theoretical partition coefficients/ambient water concentration ratio) in the actual environment. As a result, the measured maximum BAF(plasma) of inflammatory agents was up to 17 times higher than theoretical BCFplasma values, leading to possible underestimation of toxicological risk on wild fish. When the tissue blood partition coefficients (tissue/blood concentration ratios) of PPCPs were estimated, higher transportability into tissues, especially the brain, was found for psychotropic agents, but brain/plasma ratios widely varied among individual fish (up to 28-fold). In the present study, we provide a valuable data set on the intraspecies variability of PPCP pharmacokinetics, and our results emphasize the importance of determining PPCP concentrations in possible target organs as well as in the blood to assess the risk of PPCPs on wild fish.
  • Isobe Tomohiko, Sato Kentaro, Joon-Woo Kim, Tanabe Shinsuke, Suzuki Go, Nakayama Kei
    Environmental Science and Pollution Research 22 (18) 14127 - 14135 0944-1344 2015/09 [Peer-reviewed]
     Scientific journal
  • Hidenori Matsukami, Nguyen Minh Tue, Go Suzuki, Masayuki Someya, Le Huu Tuyen, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe, Hidetaka Takigami
    SCIENCE OF THE TOTAL ENVIRONMENT 514 492 - 499 0048-9697 2015/05 [Peer-reviewed]
     Scientific journal 
    Three oligomeric organophosphorus flame retardants (o-PERs), eight monomeric PFRs (m-PFRs), tetrabromobisphenol A (TBBPA), and polybrominated diphenyl ethers (PBDEs) were identified and quantified in surface soils and river sediments around the e-waste recycling area in Bui Dau, northern Vietnam. Around the e-waste recycling workshops, 1,3-phenylene bis(diphenyl phosphate) (PBDPP), bisphenol A bis(diphenyl phosphate) (BPA-BDPP), triphenyl phosphate (TPHP),TBBPA, and PBDEs were dominant among the investigated flame retardants (FRs). The respective concentrations of PBDPP, BPA-BDPP, TPHP, TBBPA and the total PBDEs were 6.6-14000 ng/g-dry, <2-1500 ng/g-dry, 11-3300 ng/g-dry, <5-2900 ng/g-dry, and 67-9200 ng/g-dry in surface soils, and 4.4-78 ng/g-dry, <2-20 ng/g-dry, 73-38 ng/g-dry, 6.0-44 ng/g-dry and 100-350 ng/g-dry in river sediments. Near the open burning site of e-waste, tris(methylphenyl) phosphate (TMPP), (2-ethylhexyl) diphenyl phosphate (EHDPP), TPHP, and the total PBDEs were abundantly with respective concentrations of <2-190 ng/g-dry, <2-69 ng/g-dry, <3-51 ng/g-dry and 1.7-67 ng/g-dry in surface soils. Open storage and burning of e-waste have been determined to be important factors contributing to the emissions of FRs. The environmental occurrence of emerging FRs, especially o-PERs, indicates that the alternation of FRs addition in electronic products is shifting in response to domestic and international regulations of PBDEs. The emissions of alternatives from open storage and burning of e-waste might become greater than those of PBDEs in the following years. The presence and environmental effects of alternatives should be regarded as a risk factor along with e-waste recycling. (C) 2015 Elsevier B.V. All rights reserved.
  • Genta Yasunaga, Yoshihiro Fujise, Ryoko Zenitani, Shinsuke Tanabe, Hidehiro Kato
    CHEMOSPHERE 126 11 - 17 0045-6535 2015/05 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB) and chlordane compounds (CHLs) were determined in the blubber of males (20-25 years old) of Antarctic minke whales, Balaenoptera bonaerensis, from the International Whaling Commission (IWC) management Areas IV (70 degrees-130 degrees E) and V (130 degrees E-170 degrees W), south 60 degrees S. The ranges of concentrations (ng g(-1) lipid wt.) for each compound were, PCBs: 7.7-89; DDTs: 29-340; HCHs: 0.20-4.3; HCB: 75-430; CHLs: 10-120, which were much lower than those in common minke whales, Balaenoptera acutorostrata, from the northern hemisphere. The levels of PCBs, HCHs, HCB and CHLs in Area IV were significantly higher than those in Area V. while the levels of DDTs in both areas were similar. For comparing the fate among four pesticides in the Antarctic Ocean avoiding the effect of variance due to food intake, the ratios of the pesticides to PCBs, which has an extremely high chemical stability and environmental persistence, were examined. The HCHs/PCBs ratio decreased by a factor of about 20 in a span of 16 years in both Areas IV and V, while temporal trends of DDTs/PCBs, HCB/PCBs and CHLs/PCBs ratios were not observed. These results indicate that PCBs, DDTs, HCB and CHLs levels did not vary or slightly decreased in Areas IV and V during the study period. However HCHs levels clearly decreased. Spatial differences seems to be related to differences in food intake among whales, and temporal differences seems to be related to the length stay of OCs in the Antarctic Ocean. (C) 2014 Elsevier Ltd. All rights reserved.
  • Hazuki Mizukawa, Kei Nomiyama, Tatsuya Kunisue, Michio X. Watanabe, Annamalai Subramanian, Hisato Iwata, Mayumi Ishizuka, Shinsuke Tanabe
    ENVIRONMENTAL RESEARCH 138 255 - 263 0013-9351 2015/04 [Peer-reviewed]
     Scientific journal 
    The concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and their hydroxylated metabolites (OH-PCBs and OH-PBDEs) were measured in the blood of Eurasian wild pigs (Sus scrofa) from a municipal waste open dumping site (DS) and a reference site (RS) in South India. We showed that contamination with OH-PCBs was higher in female pigs from the DS than in all other adult pigs. The highest OH-PCB concentrations were found in piglets from the DS. Moreover, the hepatic expression levels of CYP1A and CYP2B were higher in piglets than in their dam, implying metabolism of PCBs by cytochrome P450 (CYP) enzymes. The OH-PCB congener profiles differed according to sex and collection sites, possibly because of variations in the expression levels of phase I and phase II enzymes among individual pigs, differences in the exposure sources, and maternal transfer of parent PCBs. The hepatic CYP1A expression levels were positively correlated with the blood concentrations of 4OH-CB107, 4OH-CB162, and 4OH-CB187, implying CYP1A-dependent formation of these OH-PCBs in the pig liver. We found no significant correlations between the blood concentrations of OH-PCBs and thyroid hormones (THs); however, the thyroxin (T-4) levels were lower in pigs from the DS than in pigs from the RS. Our limited dataset suggest that induced CYP enzymes accelerate the metabolism of xenobiotics and endogenous molecules in pigs. Thus, besides parental compounds, the risk of hydroxylated metabolites entering wildlife and humans living in and around municipal open waste dumping sites should be considered. (C) 2015 Elsevier Inc. All rights reserved.
  • Akifumi Eguchi, Kei Nomiyama, Nguyen Minh Tue, Pham Thi Kim Trang, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe
    ENVIRONMENTAL RESEARCH 137 440 - 449 0013-9351 2015/02 [Peer-reviewed]
     Scientific journal 
    This study demonstrated the contamination levels of polychlorinated biphenyls (PCBs), hydroxylated PCBs (OH-PCBs), polybrominated diphenyl ethers (PBDEs), methoxylated PBDEs (MeO-PBDEs), hydroxylated PBDEs (OH-PBDEs), and bromophenols (BPhs), and their relationships with thyroid hormones (THs), in the serum of human donors from an e-waste recycling site and a rural site in Hung Yen province, Vietnam. Occupationally related exposure was indicated by significantly higher residue levels of PCBs, OH-PCBs, PBDEs, and BPhs in the serum of donors from the e-waste recycling site (median: 420, 160, 290, and 300 pg g(-1) wet wt, respectively) than those in the serum of donors from the rural site (median: 290, 82, 230, and 200 pg g(-1) wet wt, respectively). On the other hand, levels of OH-/MeO-PBDEs were significantly higher in serum of donors from the reference site (median: 160 and 20 pg g(-1) wet wt, respectively) than in those from the e-waste recycling site (median: 43 and 0.52 pg g(-1) wet wt, respectively). In addition, we implemented stepwise generalized linear models to assess the association between the levels of TH and PCBs, PBDEs, and their related compounds. In females, we found positive associations of PCBs and OH-PCB concentrations with total thyroxine, free thyroxine, total triiodothyronine, and free triiodothyronine, and a negative association with thyroid-stimulating hormone concentrations. (C) 2015 Elsevier Inc. All rights reserved.
  • Mikiko Soejima, Tetsuro Agusa, Hisato Iwata, Junko Fujihara, Takashi Kunito, Haruo Takeshita, Vi Thi Mai Lan, Tu Binh Minh, Shin Takahashi, Pham Thi Kim Trang, Pham Hung Viet, Shinsuke Tanabe, Yoshiro Koda
    LEGAL MEDICINE 17 (1) 14 - 16 1344-6223 2015/01 [Peer-reviewed]
     Scientific journal 
    The haptoglobin (HP) gene deletion allele (HPdel) is responsible for anhaptoglobinemia and a genetic risk factor for anaphylaxis reaction after transfusion due to production of the anti-HP antibody. The distribution of this allele has been explored by several groups including ours. Here, we studied the frequency of HPdel in addition to the distribution of common HP genotypes in 293 Vietnamese. The HPdel was encountered with the frequency of 0.020. The present result suggested that this deletion allele is restricted to East and Southeast Asians. Thus, this allele seems to be a potential ancestry informative marker for these populations. (C) 2014 Elsevier Ireland Ltd. All rights reserved.
  • Riyadi, Adi Slamet, Itai, Takaaki, Hayase, Daisuke, Isobe, Tomohiko, Horai, Sawako, Miller, Todd W., Omori, Koji, Sudaryanto, Agus, Ilyas, Muhammad, Setiawan, Iwan Eka, Tanabe, Shinsuke
    Chemistry Letters 44 (11) 1470 - 1472 0366-7022 2015 [Peer-reviewed]
     Scientific journal
  • Kim, Joon-Woo, Isobe, Tomohiko, Tanoue, Rumi, Chang, Kwang-Hyeon, Tanabe, Shinsuke
    Current Analytical Chemistry 11 (2) 138 - 149 1573-4110 2015 [Peer-reviewed]
     Scientific journal
  • Joon-Woo Kim, Tomohiko Isobe, Mamoru Muto, Nguyen Minh Tue, Kana Katsura, Govindan Malarvannan, Agus Sudaryanto, Kwang-Hyeon Chang, Maricar Prudente, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe
    CHEMOSPHERE 116 91 - 97 0045-6535 2014/12 [Peer-reviewed]
     Scientific journal 
    In this study, the concentrations of 10 organophosphorus flame retardants (PFRs) were determined in 89 human breast milk samples collected from Japan, the Philippines and Vietnam. Among the targeted PFRs, tris(2-chloroexyl) phosphate (TCEP) and triphenyl phosphate (TPHP) were the predominant compounds and were detected in more than 60% of samples in all three countries. The concentrations of PFRs in human breast milk were significantly higher (p < 0.05) in the Philippines (median 70 ng g(-1) lipid wt.) than those in Japan (median 22 ng g-1 lipid wt.) and Vietnam (median 10 ng g-1 lipid wt.). The present results suggest that the usage of products containing PFRs in the Philippines is higher than those of Japan and Vietnam. Comparing with a previous literature survey in Sweden, the levels of PERs in human breast milk from the Philippines were 1.5-2 times higher, whereas levels in Japan and Vietnam were 4-20 times lower, suggesting that these differences might be due to their variation in the usage of flame-retarded products utilized in each country. When daily intake of PFRs to infants via human breast milk was estimated, some individuals accumulated tris(2-butoxyethyl) phosphate (TBOEP) and TCEP were close to reference dose (RfD). This is the first report to identify PFRs in human breast milk samples from Asian countries. (C) 2014 Elsevier Ltd. All rights reserved.
  • Kei Nomiyama, Shusaku Hirakawa, Akifumi Eguch, Chika Kanbara, Daisuke Imaeda, Jean Yoo, Tatsuya Kunisue, Eun-Young Kim, Hisato Iwata, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 48 (22) 13530 - 13539 0013-936X 2014/11 [Peer-reviewed]
     Scientific journal 
    We have previously reported that high accumulation of dioxins and related compounds induced cytochrome P450 (CYP 1s) isozymes in the liver of wild Baikal seals, implying the enhanced hydroxylation of polychlorinated biphenyls (PCBs). The present study attempted to elucidate the residue concentrations and patterns of PCBs and hydroxylated PCBs (OH-PCBs) in the livers of Baikal seals. The hepatic residue concentrations were used to assess the potential effects of PCBs and OH-PCBs in combination with the analyses of serum thyroid hormones, hepatic mRNA levels, and biochemical markers. The hepatic expression levels of CYP1 genes were positively correlated with the concentration of each OH-PCB congener. This suggests chronic induction of these CYP1 isozymes by exposure to PCBs and hydroxylation of PCBs induced by CYP 1s. Hepatic mRNA expression monitoring using a custom microarray showed that chronic exposure to PCBs and their metabolites alters the gene expression levels related to oxidative stress, iron ion homeostasis, and inflammatory responses. In addition, the concentrations of OH-PCBs were negatively correlated with l-thyroxine (T-4) levels and the ratios of 3,3',5-triiodo-l-thyronine (T-3)/reverse 3,3',5'-triiodo-l-thyroninee (rT(3)). These observations imply that Baikal seals contaminated with high levels of OH-PCBs may undergo the disruption of mechanisms related to the formation (or metabolism) of T-3 and T-4 in the liver.
  • Sawako Horai, Kumiko Yanagi, Tadashi Kaname, Masatatsu Yamamoto, Izumi Watanabe, Go Ogura, Shintaro Abe, Shinsuke Tanabe, Tatsuhiko Furukawa
    ECOTOXICOLOGY 23 (9) 1681 - 1689 0963-9292 2014/11 [Peer-reviewed]
     Scientific journal 
    The present study established a primary hepatocyte culture for the small Indian mongoose (Herpestes auropunctatus). To determine the suitable medium for growing the primary hepatic cells of this species, we compared the condition of cells cultured in three media that are frequently used for mammalian cell culture: Dulbecco's Modified Eagle's Medium, RPMI-1640, and William's E. Of these, William's E medium was best suited for culturing the hepatic cells of this species. Using periodic acid-Schiff staining and ultrastructural observations, we demonstrated the cells collected from mongoose livers were hepatocytes. To evaluate the distribution of mercury (Hg) in the liver tissue, we carried out autometallography staining. Most of the Hg compounds were found in the central region of hepatic lobules. Smooth endoplasmic reticulum, which plays a role inxenobiotic metabolism, lipid/cholesterol metabolism, and the digestion and detoxification of lipophilic substances is grown in this area. This suggested that Hg colocalized with smooth endoplasmic reticulum. The results of the present study could be useful to identify the detoxification systems of wildlife with high Hg content in the body, and to evaluate the susceptibility of wildlife to Hg toxicity.
  • Le Huu Tuyen, Nguyen Minh Tue, Shin Takahashi, Go Suzuki, Pham Hung Viet, Annamalai Subramanian, Kesav A. Bulbule, Peethambaram Parthasarathy, Alagappan Ramanathan, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 194 272 - 280 0269-7491 2014/11 [Peer-reviewed]
     Scientific journal 
    Methylated polycyclic aromatic hydrocarbons (MePAHs), unsubstituted PAHs and AhR-mediated activities were determined in street dust collected from Vietnam and India using a combined approach of chemical analysis and in vitro reporter gene assay. MePAHs and PAHs diagnostic ratios indicated that the main sources of MePAHs in Vietnam were pyrogenic emissions, whereas in India there were mixed sources of pyrogenic and petrogenic emissions. AhR-mediated activities determined by using DR-CALUX assay were observed in urban street dust at mean 40,29 and 20 ng CALUX-TEQ/g dw for Hanoi, Bangalore and New Delhi, respectively. MePAHs and PAHs contributed only 5% or less to AhR-mediated activity in street dust, indicating the occurrence of unknown AhR agonists. The principal contributors to Theoretical-TEQs among target compounds were methyl benz[a]anthracene, benzo[b]- and benzo[k] fluoranthene. The present study indicates importance of MePAHs in evaluation of toxic risk related to AhR-mediated activity in urban polluted areas. (C) 2014 Elsevier Ltd. All rights reserved.
  • Daisuke Imaeda, Kei Nomiyama, Tatsuya Kunisue, Hisato Iwata, Oyuna Tsydenova, Masao Amano, Evgeny A. Petrov, Valeriy B. Batoev, Shinsuke Tanabe
    CHEMOSPHERE 114 1 - 8 0045-6535 2014/11 [Peer-reviewed]
     Scientific journal 
    We have previously demonstrated that Baikal seals (Pusa sibirica) are still being exposed to polychlorinated biphenyls (PCBs), and the population is at risk. In the present study, we measured the residue levels of PCBs and their hydroxylated metabolites (OH-PCBs) in the blood of Baikal seals and assessed the impact of OH-PCBs on the thyroid function. Blood concentrations of PCBs and OH-PCBs were in the range of 2.8130 ng g(-1) wet wt. and 0.71-4.6 ng g(-1) wet wt., respectively. Concentrations of higher-chlorinated OH-PCBs (hexa- to octa-PCBs) were more than 70% to total OH-PCB concentrations, indicating Baikal seals are mostly risked by higher-chlorinated OH-PCBs. High levels of 4OH-CB146 and 4OH-CB187 and low levels of 4OH-CB107/4'OH-CB108 found in Baikal seals were different from those in other phocidae species, suggesting the unique drug-metabolizing enzyme activities and/or contamination sources in this species. Concentrations of some OH-PCBs in males were significantly higher than those in females. These results suggest that these isomers may be preferentially transferred from mother to pup via cord blood. However, concentrations of almost all the isomers were not significantly correlated with the levels of blood total T3 and T4, implying less impact of PCB-related compounds on the thyroid hormone circulation. (C) 2014 Elsevier Ltd. All rights reserved.
  • Satoko Niimi, Mai Imoto, Tatsuya Kunisue, Michio X. Watanabe, Eun-Young Kim, Kei Nakayama, Genta Yasunaga, Yoshihiro Fujise, Shinsuke Tanabe, Hisato Iwata
    ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 108 95 - 105 0147-6513 2014/10 [Peer-reviewed]
     Scientific journal 
    Hepatic concentrations of persistent organochlorines (OCs) were determined in the common minke whale (Balaenoptera acutorostrata) from the North Pacific. To investigate the effects of OCs on the transcriptome in the minke whale, the present study constructed a hepatic oligo array of this species where 985 unique oligonucleotides were spotted and further analyzed the relationship between the OC levels and gene expression profiles of liver tissues. The stepwise multiple linear regression analysis identified 32 genes that correlated with hepatic OC levels. The mRNA expression levels of seven cytochrome P450 (CYP) genes, CYP1A1, 1A2, 208, 2E1, 3A72, 4A35, and 4V6 showed no clear correlations with the concentration of each OC, suggesting that the accumulated OCs in the liver did not reach levels that could alter CYP expression. Among the genes screened by the custom oligo array analysis, hepatic mRNA expression levels of 16 genes were further measured using quantitative real-time reverse transcription polymerase chain reaction. The mRNA levels of vitamin D-binding protein (DBP) were negatively correlated with non-ortho coplanar polychlorinated biphenyl (PCB) levels. Androgen receptor-associated coregulator 70 (ARA70) expression levels showed a significant positive correlation with concentrations of non-ortho coplanar PCB169. These correlations suggest that coplanar PCB-reduced DBP expression could suppress vitamin D receptor-mediated signaling cascades in peripheral tissues. Alternatively, the suppression of vitamin D receptor signaling cascade could be enhanced through competition with the androgen receptor signaling pathway for ARA70. In addition, a negative correlation between kynureninase and PCB169 levels was also observed, which suggest an enhanced accumulation of an endogenous aryl hydrocarbon receptor agonist, kynurenine in the minke whale population. Further studies are necessary to translate the changes in the transcriptome to toxicological outcomes including the disruption of the nervous and immune systems. (C) 2014 Elsevier Inc. All rights reserved.
  • Le Huu Tuyen, Nguyen Minh Tue, Go Suzuki, Kentaro Misaki, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 491 246 - 254 0048-9697 2014/09 [Peer-reviewed]
     Scientific journal 
    Dioxin-Responsive Chemical-Activated LUciferase gene eXpression assay (DR-CALUX) was applied to assess the total toxic activity of the mixture of PAHs and related compounds as well as dioxin-related compounds in road dust from urban areas of Hanoi, Vietnam. Road dust from Hanoi contained significantly higher DR-CALUX activities (3 to 39, mean 20 ng CALUX-TEQ/g dw) than those from a rural site (2 to 13, mean 5 ng CALUX-TEQ/g dw). The total concentrations of 24 major PAHs (Sigma(24)PAHs) in urban road dust (0.1 to 5.5, mean 2.5 mu g/g dw) were also 6 times higher than those in rural road dust (0.08 to 1.5, mean 0.4 mu g/g dw). Diagnostic ratios of PAHs indicated vehicular engine combustion as the major PAH emission source in both sites. PAHs accounted for 0.8 to 60% (mean 10%) and 2 to 76% (mean 20%) of the measured CALUX-TEQs in road dust for Hanoi the rural site, respectively. Benzo[b]-/benzo[k]fluoranthenes were the major TEQ contributors among PAHs, whereas DRCs contributed <0.1% to CALUX-TEQs for both rural and urban sites. These results suggest TEQ contribution of other aryl hydrocarbon receptor agonists in road dust. Significant PAH concentrations in urban dust indicated high mutagenic and carcinogenic potencies. Estimated results of incremental life time cancer risk (ILCR) indicated that Vietnamese populations, especially those in urban areas such as Hanoi, are potentially exposed to high cancer risk via both dust ingestion and dermal contact. This is the first study on the exposure risk of AhR agonists, including PAHs and DRCs, in urban road dust from a developing country using a combined bio-chemical analytical approach. (C) 2014 Elsevier B.V. All rights reserved.
  • Rumi Tanoue, Kei Nomiyama, Haruna Nakamura, Terutake Hayashi, Joon-Woo Kim, Tomohiko Isobe, Ryota Shinohara, Shinsuke Tanabe
    JOURNAL OF CHROMATOGRAPHY A 1355 193 - 205 0021-9673 2014/08 [Peer-reviewed]
     Scientific journal 
    In the present study, a sensitive and accurate isotope dilution method was developed for the simultaneous determination of 17 polar pharmaceutical and personal care product (PPCP) residues (logK(ow) = 1.40-5.74), including 14 pharmaceuticals and 3 personal care products, in biological organs and tissues. The proposed method involved enzymatic hydrolysis, followed by sequential clean-up using silica gel chromatography and gel permeation chromatography, and analysis via ultra-high-performance liquid chromatography with tandem mass spectrometry. This method yielded acceptable absolute recoveries (48-88%) and internal standard-corrected recoveries (90-130%) for 17 PPCPs. Method detection limits were between 0.0092 and 3.2 ng g(-1) wet weight, and the limits of quantification were between 0.020 and 8.7 ng g(-1) wet weight. The method can be used to readily detect the target compounds at trace levels while minimizing the required sample volume. The developed method was applied to the determination of 17 PPCPs in the liver and kidney of 17 birds collected from Japan and also in the plasma, liver, and brain of 7 cyprinoid fish from an effluent-dominated stream in Japan. Triclosan was detected in 5 of 11 fish-eating birds but not in non-fish-eating birds, suggesting the contamination of prey fish by the chemical. Non-steroidal anti-inflammatory drugs, antibacterial agents, and psychotropic agents were frequently detected in the fish tissues. In addition, 7 of the target compounds were found in fish brain. The median brain/plasma ratios of the psychotropic agents ranged from 1.6 (carbamazepine) to 12 (diphenhydramine), indicating high transportability to fish brain. (C) 2014 Elsevier B.V. All rights reserved.
  • Nguyen Minh Tue, Kana Katsura, Go Suzuki, Le Huu Tuyen, Takurni Takasuga, Shin Takahashi, Pham Hung Viet, Shinsuke Tanabe
    ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 106 220 - 225 0147-6513 2014/08 [Peer-reviewed]
     Scientific journal 
    Although informal e-waste recycling sites (EWRSs) are hotspots of both polychlorinated and poly-brominated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs and PBDD/Fs), human exposure to the latter has not been studied in details. This study investigated the accumulation levels and profiles of dioxin-related compounds (DRCs) in breast milk samples from women living in two Vietnamese EWRSs and estimated the intake contribution from e-waste-related exposure. Screening results using Dioxin-Responsive Chemically Activated LUciferase gene eXpression assay (DR-CALUX) showed higher dioxin-like (DL) activities in samples from the EWRS Bui Dau than in those from the EWRS Trang Minh and a reference site (2.3-10 vs 1.7-4.8 and 0.60-5.7 pg CALUX-TEQ/g lipid, n=10, 6 and 9, respectively). Chemical analysis results of selected samples show that the WHO-TEQ levels of PCDD/Fs, DL-PCBs and PBDD/Fs in EWRS samples were not significantly higher than in those from the reference site (0.22-7.4 vs 1.1-3.0 pg/g lipid) and within the Vietnamese background range, but women involved in recycling accumulated higher concentrations of PCDFs (13-15 vs 2.3-8.8 pg/g lipid) and PBDFs (1.1-1.5 vs <1.1 pg/g lipid). By comparing the DRC profile in milk of these women with the reported profile in house dust from the same site, dust ingestion was estimated to contribute most of the intake for tetraBDF, 37 per cent to 55 per cent for penta octaCDFs, but less than twenty per cent for PCDDs and DL-PCBs, and 26 per cent for total WHO-TEQs. The DL activities in some EWRS milk samples were not fully explained by chemical data, suggesting contribution from unidentified compounds. The estimated WHO-TEQ intake doses for breastfed infants (1.3-33 pg/kg/d) mostly exceeded the tolerable value, especially for those living in the EWRSs; and unidentified DRCs might increase further the dioxin-related health risk. (C) 2014 Elsevier Inc. All rights reserved.
  • Sawako Horai, Takaaki Itai, Takako Noguchi, Yusuke Yasuda, Haruki Adachi, Yuika Hyobu, Adi S. Riyadi, Ashley S. P. Boggs, Russell Lowers, Louis J. Guillette, Shinsuke Tanabe
    CHEMOSPHERE 108 159 - 167 0045-6535 2014/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of 28 trace elements (Li, Mg, Al, V. Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Tl, Hg, Pb, and Bi) in the livers of juvenile and adult American alligators inhabiting two central Florida lakes, Lake Apopka (LA), and Lake Woodruff National Wildlife Refuge (LW) and one lagoon population located in Merritt Island National Wildlife Refuge (MINWR; NASA), were determined. In juveniles from MINWR, concentrations of nine elements (Li, Fe, Ni, Sr, In, Sb, Hg, Pb and Bi) were significantly higher, whereas six elements (V, Fe, As, Sr, Hg and Bi) were elevated in adults (p < 0.05) obtained from MINWR. Significant enrichment of some trace elements in adults, relative to juveniles, was observed at all three sampling areas. Specifically, Fe, Pb and Hg were significantly elevated in adults when compared to juveniles, suggesting age-dependent accumulation of these elements. Further, As, Se and Sn showed the same trend but only in animals collected from MINWR Mean Fe concentrations in the livers of adults from LA. LW and MINWR were 177014 mu(-1) DW, 3690 mu g g(-1) DW and 5250 mu g g(-1) DW, respectively. More than half of the adult specimens from LW and MINWR exhibited elevated hepatic Fe concentrations that exceed the threshold value for toxic effects in donkey, red deer and human. These results prompted us to express our concern on possible exposure and health effects in American alligators by some trace elements derived from NASA activities. (C) 2014 Elsevier Ltd. All rights reserved.
  • Agusa Tetsuro, Pham Thi Kim Trang, Vi Mai Lan, Duong Hong Anh, Tanabe Shinsuke, Pham Hung Viet, Berg Michael
    SCIENCE OF THE TOTAL ENVIRONMENT 488 ((488-489)) 562 - 569 0048-9697 2014/08 [Peer-reviewed]
  • Akifumi Eguchi, Tatsuya Kunisue, Qian Wu, Pham Thi Kim Trang, Pham Hung Viet, Kurunthachalam Kannan, Shinsuke Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 67 (1) 29 - 41 0090-4341 2014/07 [Peer-reviewed]
     Scientific journal 
    Perchlorate (ClO4 (-)) and thiocyanate (SCN-) interfere with iodide (I-) uptake by the sodium/iodide symporter, and thereby these anions may affect the production of thyroid hormones (THs) in the thyroid gland. Although human exposure to perchlorate and thiocyanate has been studied in the United States and Europe, few investigations have been performed in Asian countries. In this study, we determined concentrations of perchlorate, thiocyanate, and iodide in 131 serum samples collected from 2 locations in Northern Vietnam, Bui Dau (BD; electrical and electronic waste [e-waste] recycling site) and Doung Quang (DQ; rural site) and examined the association between serum levels of these anions with levels of THs. The median concentrations of perchlorate, thiocyanate, and iodide detected in the serum of Vietnamese subjects were 0.104, 2020, and 3.11 ng mL(-1), respectively. Perchlorate levels were significantly greater in serum of the BD population (median 0.116 ng mL(-1)) than those in the DQ population (median 0.086 ng mL(-1)), which indicated greater exposure from e-waste recycling operations by the former. Serum concentrations of thiocyanate were not significantly different between the BD and DQ populations, but increased levels of this anion were observed among smokers. Iodide was a significant positive predictor of serum levels of FT3 and TT3 and a significant negative predictor of thyroid-stimulating hormone in males. When the association between serum levels of perchlorate or thiocyanate and THs was assessed using a stepwise multiple linear regression model, no significant correlations were found. In addition to greater concentrations of perchlorate detected in the e-waste recycling population, however, given that lower concentrations of iodide were observed in the serum of Vietnamese females, detailed risk assessments on TH homeostasis for females inhabiting e-waste recycling sites, especially for pregnant women and their neonates, are required.
  • Andreia Cruz, Isabel Henriques, Ana C. A. Sousa, Ines Baptista, Adelaide Almeida, Shin Takahashi, Shinsuke Tanabe, Antonio Correia, Satoru Suzuki, Ana Maria Anselmo, Sonia Mendo
    ENVIRONMENTAL RESEARCH 132 430 - 437 0013-9351 2014/07 [Peer-reviewed]
     Scientific journal 
    Tributyltin (TBT) is a biocide extremely toxic to a wide range of organisms, which has been used for decades in antifouling paints. Despite its global ban in 2008, TBT is still a problem of great concern due to the high levels trapped in sediments. Aeromonas molluscorum Av27 is a TBT degrading bacterium that was isolated from an estuarine system. We investigated the ability and the role of this bacterium on TBT degradation in this estuarine system, using a microcosm approach in order to mimic environmental conditions. The experiment was established and followed for 150 days. Simultaneously, changes in the indigenous bacterial community structure were also investigated. The results revealed a maximum TBT degradation rate of 28% accompanied by the detection of the degradation products over time. Additionally, it was observed that TBT degradation was significantly enhanced by the presence of Av27. In addition a significantly higher TBT degradation occurred when the concentration of Av27 was higher. TBT degradation affected the bacterial community composition as revealed by the changes in the prevalence of Proteobacteria subdivisions, namely the increase of Deltaproteobacteria and the onset of Epsilonproteobacteria. However, the addition of Av27 strain did not affect the dominant phylotypes. Total bacterial number, bacterial biomass productivity, 16S rRNA gene and denaturing gradient gel electrophoresis (DGGE) analyses also indicated alterations on the bacterial community structure over time, with bacteria non-tolerant to pollutants increasing their representativeness, as, for instance, the increase of the number of Alphaproteobacteria clones from 6% in the beginning to 12% at the end of the experiment. The work herein presented confirms the potential of Av27 strain to be used in the decontamination of TBT-polluted environments. (C) 2014 Elsevier Inc. All rights reserved.
  • Ana C. A. Sousa, M. Ramiro Pastorinho, Shin Takahashi, Shinsuke Tanabe
    ENVIRONMENTAL CHEMISTRY LETTERS 12 (1) 117 - 137 1610-3653 2014/03 [Peer-reviewed]
     
    Organotin compounds are industrial chemicals used as biocides, polyvinyl chloride stabilizers and industrial catalysts for the manufacture of silicone and polyurethane foams. Despite multiple applications, organotin notoriety is due to tributyltin, a potent biocide used in antifouling paints. Because of the intensive use of tributyltin for the protection of ships' hulls, tributyltin has been largely released into waters, resulting in adverse and even bizarre effects on aquatic organisms, such as imposex in gastropods. However, organotins include other compounds such as tributyltin derivatives, phenyltins and octyltins. Organotin use in plastics, silicone and foams results in their occurrence almost everywhere, e.g., clothes, toys, wallpaper, food containers, household piping and medical devices. Hence, humans are exposed to organotins not solely through ingestion of contaminated seafood but also through direct contact with treated products and by inhalation and ingestion of dust. As a consequence, organotins have been detected in human samples. Toxicity data reveal that organotins are endocrine disruptors, immunotoxicants, carcinogens and obesogens. Here, we review the levels, fate and effects of organotin compounds toward wildlife and humans, starting with a description of organotin applications, with particular incidence in antifouling paints. The global contamination of the marine environment and the deleterious effects of tributyltin onto nontarget organisms are addressed, with particular attention to the imposex phenomenon. The restrictions on tributyltin use in antifouling paints are also described alongside with the new regulations for organotins in consumer products. The sources and pathways of organotins in the environment are discussed, studies in human exposure are presented, and future research is proposed.
  • Takako Noguchi, Takaaki Itai, Nguyen Minh Tue, Tetsuro Agusa, Nguyen Ngoc Ha, Sawako Horai, Pham Thi Kim Trang, Pham Hung Viet, Shin Takahashi, Shinsuke Tanabe
    JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT 16 (1) 46 - 51 1438-4957 2014/02 [Peer-reviewed]
     Scientific journal 
    Human exposure to lead (Pb) due to uncontrolled Pb-acid battery recycling has been an environmental health issue in newly developed industrial regions. We conducted a human monitoring survey in Dong Mai, a battery recycling village in Vietnam, to assess exposure status to Pb. Lead level was measured in hair, blood and urine samples of residents in Dong Mai and two reference sites during 4 years spanning 2007-2011. In Dong Mai, Pb levels in three matrixes were significantly higher than those in reference sites. Blood Pb levels of all adults and children exceeded 10 mu g/dL, the Centers for Disease Control and Prevention definition of an elevated blood Pb level. Clear increase of urinary delta-aminolevulinic acid (ALA) level with increasing blood Pb level indicated disruption of heme synthesis. One adult exceeded 100 mu g/dL of blood Pb, where encephalopathy is of concern. The blood Pb levels achieved various toxic effect threshold values, and elevated blood Pb was not limited to recycling workers, but was also in children and women of reproductive age. Serious pollution status of Dong Mai village suggests an importance of further monitoring surveys in various developing Asian countries.
  • Kei Nomiyama, Chika Kanbara, Mari Ochiai, Akifumi Eguchi, Hazuki Mizukawa, Tomohiko Isobe, Takashi Matsuishi, Tadasu K. Yamada, Shinsuke Tanabe
    MARINE ENVIRONMENTAL RESEARCH 93 15 - 22 0141-1136 2014/02 [Peer-reviewed]
     Scientific journal 
    Information on accumulation of halogenated phenolic contaminants in the blood of marine mammal is limited. The present study, we determined the residue levels and patterns of chlorinated and brominated phenolic contaminants (OH-PCBs, OH-PBDEs and bromophenols) in the blood collected from pinnipeds (northern fur seal, spotted seal, Steller sea lion and ribbon seal) and small cetaceans (harbor porpoise and Dall's porpoise) from Japanese coastal waters. Concentrations of PCBs and OH-PCBs found in pinnipeds were the same as in small cetaceans living in the same coastal area. However, significantly lower concentrations of brominated compounds (PBDEs, MeO-PBDEs, OH-PBDEs) were found in the blood of pinnipeds than the levels found in cetacean species which live same area (p < 0.05). This difference of accumulation pattern suggested pinnipeds have an enhanced capability to degrade organobromine compounds relative to cetaceans. (C) 2013 Elsevier Ltd. All rights reserved.
  • Takaaki Itai, Masanari Otsuka, Kwadwo Ansong Asante, Mamoru Muto, Yaw Opoku-Ankomah, Osmund Duodu Ansa-Asare, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 470 707 - 716 0048-9697 2014/02 [Peer-reviewed]
     Scientific journal 
    Illegal import and improper recycling of electronic waste (e-waste) are an environmental issue in developing countries around the world. African countries are no exception to this problem and the Agbogbloshie market in Accra, Ghana is a well-known e-waste recycling site. We have studied the levels of metal(loid)s in the mixtures of residual ash, formed by the burning of e-waste, and the cover soil, obtained using a portable X-ray fluorescence spectrometer (P-XRF) coupled with determination of the 1 M HCl-extractable fraction by an inductively coupled plasma mass spectrometer. The accuracy and precision of the P-XRF measurements were evaluated by measuring 18 standard reference materials; this indicated the acceptable but limited quality of this method as a screening tool. The HCl-extractable levels of Al, Co, Cu, Zn, Cd, In, Sb, Ba, and Pb in 10 soil/ash mixtures varied by more than one order of magnitude. The levels of these metal(loid)s were found to be correlated with the color (i.e., soil/ash ratio), suggesting that they are being released from disposed e-waste via open burning. The source of rare elements could be constrained using correlation to the predominant metals. Human hazard quotient values based on ingestion of soil/ash mixtures exceeded unity for Pb, As, Sb, and Cu in a high-exposure scenario. This study showed that along with common metals, rare metal(loid)s are also enriched in the e-waste burning site. We suggest that risk assessment considering exposure to multiple metal(loid)s should be addressed in studies of e-waste recycling sites. (C) 2013 Elsevier B.V. All rights reserved.
  • Ing Chen, Hsin-Yi Yu, Wei-Cheng Yang, Shin Nishida, Tomohiko Isobe, Shinsuke Tanabe, Alastair Watson, Lien-Siang Chou
    RAFFLES BULLETIN OF ZOOLOGY 62 188 - 199 0217-2445 2014 [Peer-reviewed]
     Scientific journal 
    The short-finned pilot whale (Globicephala macrorhynchus) is a mid-sized toothed whale, widely distributed throughout warm-temperate to tropical regions of the Atlantic, Pacific, and Indian oceans. There is suggestive evidence that the taxonomy within the species is unresolved: a "Southern form" in southern Japanese waters is considered distinctive in its morphological, ecological, and genetic characteristics to a "Northern form" found in northern Japanese waters, and each might represent different subspecies or species. Short-finned pilot whales in the tropical west Pacific are poorly studied and their taxonomic status remains uncertain. The aim of this study was to determine the phenotype(s) and genotype(s) of pilot whales sighted or sampled from Taiwanese waters and compare them with whales found in adjacent Northeast and Southeast Asian waters. We examined 892 photographs taken from 14 groups of whales at sea around Taiwan, as well as the body length and photographic records of 19 whales stranded on the Taiwanese coast including genetic data (derived from a 689-bp mitochondrial DNA control region fragment) from eight of these. We also examined a group of short-finned pilot whales in a video clip filmed in the South China Sea, as well as a 593-bp mitochondrial DNA control region fragment sampled from two whales in Philippine waters. Our results revealed morphological and genetic similarities to available data from the more northerly located "Southern form" short-finned pilot whales from Japan, and indicate that the Southern form whales are indeed distributed more southward into the tropical west Pacific: viz, in the waters around Taiwan, in the South China Sea, and in the Philippines. The extent of the southern boundary for the range of the Southern form of short-finned pilot whales in the tropical west Pacific Ocean could be better defined with further observational and genetic studies.
  • Go Suzuki, Nguyen M. Tue, Shin Takahashi, Shinsuke Tanabe, Shin-ichi Sakai, Hidetaka Takigami
    CURRENT ORGANIC CHEMISTRY 18 (17) 2231 - 2239 1385-2728 2014 [Peer-reviewed]
     Scientific journal 
    Indoor dust is a sink for many kinds of pollutants, including flame retardants (FRs), plasticizers and various degradation products, derived from household products. Recently, we have put particular emphasis on the evaluation of indoor dust as an excellent indicator of important contaminants for chemical risk management throughout the lifecycle of household product. Our research has focused on effect-based approach using in vitro bioassays together with instrumental analyses in an attempt to conduct hazard characterization determining the presence and activity profile of contaminants detected in house dust. This approach will lead to a determination of priority pollutants, their impurities and by-products for further assessment from the list of chemicals manufactured and distributed worldwide. Here, we introduce some background studies and results obtained by using effect-based approach for house dust, revealing importance of dioxin-like compounds, thyroid and reproductive toxicants used and contained in household products. Based on outcomes from previous studies here summarized, it can be suggested that effect-based approach is a useful scheme to determine contaminants and endpoints in indoor dust for priority assessment on in vitro toxicological point of view. Further integration of exposure and effect analysis for indoor dust will lead to appropriate chemical risk management throughout various household products' lifecycles.
  • Akifumi Eguchi, Kei Nomiyama, Mari Ochiai, Hazuki Mizukawa, Yasuko Nagano, Katsuhiro Nakagawa, Kouki Tanaka, Haruhiko Miyagawa, Shinsuke Tanabe
    TALANTA 118 253 - 261 0039-9140 2014/01 [Peer-reviewed]
     Scientific journal 
    In this study, we developed a comprehensive, highly sensitive, and robust method for determining 53 congeners of three to eight chlorinated OH-PCBs in liver and brain samples by using isotope dilution gas chromatography (GC) coupled with electron capture negative ionization mass spectrometry (ECNI-MS). These results were compared with those from GC coupled with electron ionization high-resolution mass spectrometry (El-HRMS). Clean-up procedures for analysis of OH-PCBs homologs in liver and brain samples involve a pretreatment step consisting of acetonitrile partition and 5% hydrated silica-gel chromatography before derivatization. Recovery rates of tri- and tetra-chlorinated OH-PCBs in the acetonitrile partition method followed by the 5% hydrated silica-gel column (82% and 91%) were higher than conventional sulfuric acid treatment (2.0% and 3.5%). The method detection limits of OH-PCBs for each matrix obtained by GC/ECNI-MS and GC/EI-HRMS were 0.58-2.6 pg g(-1) and 0.36-1.6 pg g(-1) wet wt, respectively. Recovery rates of OH-PCB congeners in spike tests using sample matrices (10 and 50 pg) were 64.7-117% (CV: 4.7-14%) and 70.4-120% (CV: 2.3-12%), respectively. This analytical method may enable the simultaneous detection of various OH-PCBs from complex tissue matrices. Furthermore, this method allows more comprehensive assessment of the biological effects of OH-PCB exposure on critical organs. (C) 2013 Elsevier B.V. All rights reserved.
  • Muhammad Ilyas, Agus Sudaryanto, Iwan E. Setiawan, Adi S. Riyadi, Tomohiko Isobe, Shinsuke Tanabe
    Chemosphere 93 (8) 1500 - 1510 0045-6535 2013/11 [Peer-reviewed]
     Scientific journal 
    We investigated the PCBs, PBDEs and HBCDs contamination in sludge, sediments and fish from various locations including raw leachate pond, leachate treatment plans (LTPs), control wells and reference site at open landfill of municipal dumpsite, Surabaya City, Indonesia. 62 PCBs and 14 PBDEs congeners, and 3 HBCDs isomers were identified and quantified using GC-MS and LC-MS/MS, respectively. Concentration ranges and median (value in parentheses) of PCBs, PBDEs and HBCDs were from not detected (ND) to 60 (3.9) ngg-1 dw, 0.0075 to 45 (4.5) ngg-1 dw and ND to 2.8 (0.052) ngg-1 dw in sludge and sediments, respectively. While in two polled of fish samples were 30-55ngg-1 lw, 6.6-11ngg-1 lw and 1.6-3.3ngg-1 lw, respectively. Among the sampling sites, the highest level of PCBs and PBDEs were detected in sludge from raw leachate pond. However, PCBs and PBDEs levels were showing decreased in LTP-1 that could be due to the bacterial degradation but not in LTP-2, HBCDs were more stable in both LTPs. Levels of PCBs and BFRs in sludge at the present study were lower than those reported in sewage sludge reported from some other countries. PCBs profiles were mainly composed in that order by CB-138, -153, -180, -101, -118 and -28, while by BDE-47, -99, -100, -153, -154 and -28 for PBDEs in sludge, sediments and fish. Profiles of HBCDs were predominantly composed by γ- and α-isomers in sludge and fish, respectively. Debromination, dechlorination, commercial formulations used and congener-specific accumulation of those contaminants are the factors influenced the profiles. © 2013 Elsevier Ltd.
  • Shino Kitamura, Takashi Matsuishi, Tadasu K. Yamada, Yuko Tajima, Hajime Ishikawa, Shinsuke Tanabe, Hajime Nakagawa, Yoshikazu Uni, Syuiti Abe
    MARINE MAMMAL SCIENCE 29 (4) 755 - 766 0824-0469 2013/10 [Peer-reviewed]
     Scientific journal
  • Nguyen Minh Tue, Go Suzuki, Shin Takahashi, Kurunthachalam Kannan, Hidetaka Takigami, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 181 75 - 80 0269-7491 2013/10 [Peer-reviewed]
     Scientific journal 
    This study analysed sulphuric-acid-treated extracts of house dust from New York State with DR-CALUX assay and HRGC-HRMS to elucidate the total dioxin-like (DL) activities, the occurrence of various dioxin-related compounds (DRCs), including PBDD/Fs, and their toxic contribution. The DL activities were 30 -8000, median 210 pg CALUX-TEQ/g. PCDD/Fs, PBDD/Fs and DL-PCBs were detected with a large variation in concentrations (0.12-80, 0.33-150, 0.46-35, medians 1.7, 2.1 and 5.6 ng/g, respectively) and profiles, indicating the existence of multiple contamination sources in homes. PCDD/Fs, PBDD/Fs and DL-PCBs with known potency theoretically contributed <1%-130%, <1%-21% and <1%-6.8%, respectively, of the measured CALUX-TEQs. These results and those from DR-CALUX assays with fractionated dust extracts indicated that a substantial portion of the CALUX-TEQs could be caused by unknown dust contaminants. Considering that the DRC intake from indoor dust ingestion can be significant, identification of unknown DL contaminants in indoor dust is necessary. (C) 2013 Elsevier Ltd. All rights reserved.
  • Mari Ochiai, Kei Nomiyama, Tomohiko Isobe, Hazuki Mizukawa, Tadasu K. Yamada, Yuko Tajima, Takashi Matsuishi, Masao Amano, Shinsuke Tanabe
    CHEMOSPHERE 92 (7) 803 - 810 0045-6535 2013/08 [Peer-reviewed]
     Scientific journal 
    The present study investigated polychlorinated biphenyls (PCBs) and hydroxylated metabolites of PCBs (OH-PCBs) in blood from three porpoise species: finless porpoises (Neophocaena phocaenoides), harbor porpoises (Phocoena phocoena), and Dall's porpoises (Phocoenoides dalli). The porpoises were found stranded or were bycaught along the Japanese coast. Concentrations of OH-PCB were the highest in Dall's porpoises (58 pg g(-1) wet wt), second highest in finless porpoises (20 pg g(-1) wet wt), and lowest in harbor porpoises (8.3 pg g(-1) wet wt). The concentrations in Dall's porpoises were significantly higher than the concentrations in finless porpoises and harbor porpoises (p < 0.05 and p < 0.01, respectively). There was a positive correlation between PCB and OH-PCB concentrations (r = 0.67, p < 0.001), suggesting the possible concentration-dependent induction of CYP enzymes. The three porpoise species may have exceptionally low metabolic capacities compared with other marine and terrestrial mammals, because low OH-PCB/PCB concentration ratios were found, which were 0.0016 for Dall's porpoises, 0.0013 for harbor porpoises, and 0.00058 for finless porpoises. Distinct differences in the OH-PCB congener patterns were observed for the three species, even though they are taxonomically closely related. (c) 2013 Elsevier Ltd. All rights reserved.
  • Kwadwo Ansong Asante, Shin Takahashi, Takaaki Itai, Tomohiko Isobe, Gnanasekaran Devanathan, Mamoru Muto, Seth Koranteng Agyakwah, Sam Adu-Kumi, Annamalai Subramanian, Shinsuke Tanabe
    ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 94 123 - 130 0147-6513 2013/08 [Peer-reviewed]
     Scientific journal 
    Fish consumption is known to have several health benefits for humans. However, the accumulation of toxic contaminants, such as PCBs, PBDEs and HBCDs in fish could pose health hazards. These contaminants were measured in tilapia fish species collected from Ghana. Mean levels were PCBs (62 ng/g lw), PBDEs (7.3 ng/g lw) and HBCDs (1.2 ng/g lw) and the predominance of CB-153, CB-138, CB-180, BDE-47 and alpha-HBCD is in concordance with scientific literature. The congener profiles of PBDEs and PCBs in the fish suggest that sources of Penta- and Deca-BDE technical mixtures as well as technical PCB mixture (Clophen A60) exist in Ghana, while textile operations and associated release of untreated wastewater are likely to be significant sources of HBCDs. Comparison of the results with some reported studies showed moderate contamination in Ghana although Ghana is a developing country in Africa. Concentrations of PCBs measured in all the specimens in this study were below the food safety guidelines issued by the Food and Drug Administration, USA and the European Commission. The calculated hazard index levels of the target contaminants were below the threshold value of one, indicating that the levels of the target contaminants do not seem to constitute a health risk via fish consumption, with regard to PCBs, PBDEs and HBCDs, based on the limited number of samples that was accounted for in this study. However, due to the continuous discharge of untreated effluents, follow up studies are warranted as the consumption of fish is the primary route of human exposure to PCBs. This maiden report on the status of PBDEs and HBCDs in fish from Ghana will contribute to the knowledge about environmental contamination by POPs in a less industrialized region of the world so far sparsely covered in the literature. (C) 2013 Elsevier Inc. All rights reserved.
  • Tomohiko Isobe, Shohei P. Ogawa, Rina Sugimoto, Karri Ramu, Agus Sudaryanto, Govindan Malarvannan, Gnanasekaran Devanathan, Babu Rajendran Ramaswamy, Natesan Munuswamy, Deavaraj Sankar Ganesh, Jeyaraj Sivakumar, A. Sethuraman, V. Parthasarathy, Annamalai Subramanian, Jennifer Field, Shinsuke Tanabe
    ENVIRONMENTAL MONITORING AND ASSESSMENT 185 (7) 5627 - 5637 0167-6369 2013/07 [Peer-reviewed]
     Scientific journal 
    Perchlorate contamination was investigated in groundwater and surface water from Sivakasi and Madurai in the Tamil Nadu State of South India. Sensitive determination of perchlorate (LOQ = 0.005 mu g/L) was achieved by large-volume (500 mu L) injection ion chromatography coupled with tandem mass spectrometry. Concentrations of perchlorate were < 0.005-7,690 mu g/L in groundwater (n = 60), < 0.005-30.2 mu g/L in surface water (n = 11), and 0.063-0.393 mu g/L in tap water (n = 3). Levels in groundwater were significantly higher in the fireworks factory area than in the other locations, indicating that the fireworks and safety match industries are principal sources of perchlorate pollution. This is the first study that reports the contamination status of perchlorate in this area and reveals firework manufacture to be the pollution source. Since perchlorate levels in 17 out of 57 groundwater samples from Sivakasi, and none from Madurai, exceeded the drinking water guideline level proposed by USEPA (15 mu g/L), further investigation on human health is warranted.
  • Joon-Woo Kim, Nguyen Minh Tue, Tomohiko Isobe, Kentaro Misaki, Shin Takahashi, Pham Hung Viet, Shinsuke Tanabe
    ENVIRONMENTAL MONITORING AND ASSESSMENT 185 (4) 2909 - 2919 0167-6369 2013/04 [Peer-reviewed]
     Scientific journal 
    There are very few reports on the contamination by perfluorinated chemicals (PFCs) in the environment of developing countries, especially regarding their emission from waste recycling and disposal sites. This is the first study on the occurrence of a wide range of PFCs (17 compounds) in ambient water in Vietnam, including samples collected from a municipal dumping site (MD), an e-waste recycling site (ER), a battery recycling site (BR) and a rural control site. The highest PFC concentration was found in a leachate sample from MD (360 ng/L). The PFC concentrations in ER and BR (mean, 57 and 16 ng/L, respectively) were also significantly higher than those detected in the rural control site (mean, 9.4 ng/L), suggesting that municipal solid waste and waste electrical and electronic equipment are potential contamination sources of PFCs in Vietnam. In general, the most abundant PFCs were perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluoroundecanoic acid (PFUDA; < 1.4-100, < 1.2-100, and < 0.5-20 ng/L, respectively). Interestingly, there were specific PFC profiles: perfluoroheptanoic acid and perfluorohexanoic acid (88 and 77 ng/L, respectively) were almost as abundant as PFOA in MD leachate (100 ng/L), whereas PFNA was prevalent in ER and BR (mean, 17 and 6.2 ng/L, respectively) and PFUDA was the most abundant in municipal wastewater (mean, 5.6 ng/L), indicating differences in PFC contents in different waste materials.
  • Go Suzuki, Nguyen Minh Tue, Govindan Malarvannan, Agus Sudaryanto, Shin Takahashi, Shinsuke Tanabe, Shin-ichi Sakai, Abraham Brouwer, Naoto Uramaru, Shigeyuki Kitamura, Hidetaka Taldgami
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 47 (6) 2898 - 2908 0013-936X 2013/03 [Peer-reviewed]
     Scientific journal 
    Indoor dust is a sink for many kinds of pollutants, including flame retardants (FRs), plasticizers, and their contaminants and degradation products. These pollutants can be migrated to indoor dust from household items such as televisions and computers. To reveal high-priority end points of and contaminant candidates in indoor dust, using CALUX reporter gene assays based on human osteosarcoma (U2OS) cell lines, we evaluated and characterized the endocrine-disrupting potencies of crude extracts of indoor dust collected from Japan (n = 8), the United States (n = 21), Vietnam (n = 10), the Philippines (n = 17), and Indonesia (n = 10) and for 23 selected FRs. The CALUX reporter gene assays used were specific for compounds interacting with the human androgen receptor (AR), estrogen receptor alpha (ER alpha), progesterone receptor (PR), glucocorticoid receptor (GR), and peroxisome proliferator-activated receptor gamma 2 (PPAR gamma 2). Indoor dust extracts were agonistic to ER alpha, GR, and PPAR gamma 2 and antagonistic against AR, PR, GB., and PPAR gamma 2. In comparison, a majority of FRs was agonistic to ER alpha and PPAR gamma 2 only, and some FRs demonstrated receptor-specific antagonism against all tested nuclear receptors. Hierarchical clustering clearly indicated that agonism of ER alpha and antagonism of AR and PR were common, frequently detected end points for indoor dust and tested FRs. Given our previous results regarding the concentrations of FRs in indoor dust and in light of our current results, candidate contributors to these effects include not only internationally controlled brominated FRs but also alternatives such as some phosphorus-containing FRs. In the context of indoor pollution, high-frequency effects of FRs such as agonism of ER alpha and antagonism of AR and PR are candidate high-priority end points for further investigation.
  • Hazuki Mizukawa, Kei Nomiyama, Susumu Nakatsu, Shuuji Yachimori, Terutake Hayashi, Yutaka Tashiro, Yasuko Nagano, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 174 28 - 37 0269-7491 2013/03 [Peer-reviewed]
     Scientific journal 
    Residue levels and patterns of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), their hydroxylated metabolites (OH-PCBs, OH-PBDEs), and methoxylated PBDEs (MeO-PBDEs) in the blood of various terrestrial mammals in Japan, including cats, raccoon dogs, dogs, masked palm civets, foxes, raccoons, badgers, and mongooses were determined. Tri- through penta-chlorinated OH-PCBs were predominant in cat blood, whereas hexa- through octa-chlorinated OH-PCBs were found in other species. High proportion of BDE209 was found in all species, suggesting exposure to municipal waste and soil containing higher levels of deca-BDE products. 6OH-/MeO-BDE47 and 2'OH-/MeO-BDE68 were dominant in all terrestrial mammals. This is first report on the detection of OH-/MeO-PBDEs in the blood of terrestrial mammals. High concentrations of OH-/MeO-PBDEs were found in cats, suggesting the intake of these compounds from seafood. Cats exhibited higher accumulation and specific patterns of OH-PCBs, OH-PBDEs, and MeO-PBDEs, they may be at a high risk from these metabolites. (C) 2012 Elsevier Ltd. All rights reserved.
  • Akifimi Eguchi, Tomohiko Isobe, Karri Ramu, Nguyen Minh Tue, Agus Sudaryanto, Gnanasekaran Devanathan, Pham Hung Viet, Rouch Seang Tana, Shin Takahashi, Annamalai Subramanian, Shinsuke Tanabe
    Chemosphere 90 (9) 2365 - 2371 0045-6535 2013/03 [Peer-reviewed]
     Scientific journal 
    In Asian developing countries, large amounts of municipal wastes are dumped into open dumping sites each day without adequate management. This practice may cause several adverse environmental consequences and increase health risks to local communities. These dumping sites are contaminated with many chemicals including brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs).BFRs may be released into the environment through production processes and through the disposal of plastics and electronic wastes that contain them. The purpose of this study was to elucidate the status of BFR pollution in municipal waste dumping sites in Asian developing countries. Soil samples were collected from six open waste dumping sites and five reference sites in Cambodia, India, Indonesia, Malaysia, and Vietnam from 1999 to 2007. The results suggest that PBDEs are the dominant contaminants in the dumping sites in Asian developing countries, whereas HBCD contamination remains low. Concentrations of PBDEs and HBCDs ranged from ND to 180 μg/kg dry wt and ND to 1.4 μg/kg dry wt, respectively, in the reference sites and from 0.20 to 430 μg/kg dry wt and ND to 2.5 μg/kg dry wt, respectively, in the dumping sites. Contamination levels of PBDEs in Asian municipal dumping sites were comparable with those reported from electronic waste dismantling areas in Pearl River delta, China. © 2012 Elsevier Ltd.
  • Michio X. Watanabe, Tatsuya Kunisue, Norifumi Ueda, Masato Nose, Shinsuke Tanabe, Hisato Iwata
    ENVIRONMENT INTERNATIONAL 53 53 - 61 0160-4120 2013/03 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorine compounds (OCs) including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) in the liver and adipose tissue of Japanese cadavers were measured, and their toxicokinetics were examined in association with hepatic cytochrome P450 (CYP) 1A protein expression levels. Total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) were 66 +/- 74 and 65 +/- 57 pg/g lipid weight (mean +/- S.D.) in the liver and adipose tissue, respectively. Total PCBs (sum of 62 congeners targeted), p,p'-dichlorodiphenyl-dichloroethylene (p,p'-DDE) and beta-hexachlorocyclohexane (beta-HCH) were detected at concentrations over 1 mu g/g lipid in both tissues of some specimens. For most of the dioxin-like congeners, total PCBs, p,p'-DDE, oxychlordane, alpha- and beta-HCH, hexachlorobenzene (HCB), and tris(4-chlorophenyl)methane (TCPMe), age-dependent increases in concentrations were found in the adipose tissue of males. No such age-dependent trend was observed in the liver, suggesting that there are different mechanisms underlying the hepatic concentrations of OCs. Immunoblot analyses indicated detectable expression of hepatic CYP1A2 protein, whereas no CYP1A1 protein was detected. The CYP1A2 expression levels were positively correlated with concentrations (on wet weight basis) of 2,3,4,7,8-P5CDF, the dominant TEQ-contributed congeners in the liver, indicating the induction of this CYP. Hepatic CYP1A2 protein levels were strongly correlated with the liver to adipose concentration (L/A) ratios of PCDD/F congeners with more than 5 chlorine atoms. Together with higher concentrations of the congeners in the liver than in the adipose tissue, the observation on L/A ratios of highly chlorinated PCDD/Fs suggests that induced hepatic CYP1A2 protein is involved in their sequestration in this human population, as observed in model animals (rodents). Nonetheless, the magnitude of hepatic sequestration (L/A ratio) of PCDD/Fs in this human population was lower than in other mammals and birds, reported previously. This study emphasizes the fact that toxicokinetics of some OCs can be affected at least partly by CYP1A2 protein levels in humans. For the extrapolation of their toxicokinetics from model animals to humans, knowledge on the induction and sequestration potencies of CYP1A is necessary. (C) 2013 Elsevier Ltd. All rights reserved.
  • Joon-Woo Kim, Tomohiko Isobe, Agus Sudaryanto, Govindan Malarvannan, Kwang-Hyeon Chang, Mamoru Muto, Maricar Prudente, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 20 (2) 812 - 822 0944-1344 2013/02 [Peer-reviewed]
     Scientific journal 
    The use of organophosphorus flame retardants (PFRs) as flame retardants and plasticizers has increased due to the ban on common polybrominated diphenyl ether mixtures. However, only limited information on PFR contamination is available so far from Southeast Asia. In the present study, residual levels of PFRs in house dust and exposure through dust ingestion were investigated in the Philippines. House dust samples (n = 37) were collected from Malate (residential area) and Payatas (municipal dumping area) in the Philippines and analyzed using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry. Among the targeted seven PFRs, triphenyl phosphate (TPP) was the predominant compound. Median levels of I PFRs pound in Malate (530 ng/g) were two times higher (p < 0.05) than in Payatas (240 ng/g). The estimated daily intake of PFRs in the Philippines (of areas studied) via house dust ingestion was below the guideline values. House dust may be an important contributor in the overall exposure of humans to TPP even when considering dietary sources. To our knowledge, this is a first report on PFR contamination in house dust from developing country. PFRs were ubiquitously detected in the home environments in the Philippines. Although estimated exposure levels through dust ingestion were below the guideline, it was suggested that toddlers are at higher risk. Therefore, further investigations to understand the behavior of PFRs in house and other microenvironments and overall exposure pathways for the country's populace to PFRs are necessary.
  • Nguyen Minh Tue, Shin Takahashi, Go Suzuki, Tomohiko Isobe, Pham Hung Viet, Yuso Kobara, Nobuyasu Seike, Gan Zhang, Agus Sudaryanto, Shinsuke Tanabe
    ENVIRONMENT INTERNATIONAL 51 160 - 167 0160-4120 2013/01 [Peer-reviewed]
     Scientific journal 
    This study investigated the occurrence of polychlorinated biphenyls (PCBs), and several additive brominated flame retardants (BFRs) in indoor dust and air from two Vietnamese informal e-waste recycling sites (EWRSs) and an urban site in order to assess the relevance of these media for human exposure. The levels of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), 1,2-bis-(2,4,6-tribromophenoxy) ethane (BTBPE) and decabromodiphenyl ethane (DBDPE) in settled house dust from the EWRSs (130-12,000, 5.4-400, 5.2-620 and 31-1400 ng g(-1), respectively) were significantly higher than in urban house dust but the levels of PCBs (4.8-320 ng g(-1)) were not higher. The levels of PCBs and PBDEs in air at e-waste recycling houses (1000-1800 and 620-720 pg m(-3), respectively), determined using passive sampling, were also higher compared with non-e-waste houses. The composition of BFRs in EWRS samples suggests the influence from high-temperature processes and occurrence of waste materials containing older BFR formulations. Results of daily intake estimation for e-waste recycling workers are in good agreement with the accumulation patterns previously observed in human milk and indicate that dust ingestion contributes a large portion of the PBDE intake (60%-88%), and air inhalation to the low-chlorinated PCB intake (>80% for triCBs) due to their high levels in dust and air, respectively. Further investigation of both indoor dust and air as the exposure media for other e-waste recycling-related contaminants and assessment of health risk associated with exposure to these contaminant mixtures is necessary. (C) 2012 Elsevier Ltd. All rights reserved.
  • Govindan Malarvannan, Tomohiko Isobe, Adrian Covaci, Maricar Prudente, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 442 366 - 379 0048-9697 2013/01 [Peer-reviewed]
     Scientific journal 
    Paired human breast milk and scalp hair samples (n =30) were obtained in 2008 from primipara and multipara mothers living in two locations in the Philippines viz., Payatas, a waste dumpsite, and Malate, a non-dumpsite. Samples were analyzed for three groups of organohalogenated compounds, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs). PCBs were the predominantly identified compounds (median: 70 ng/g lipid wt.) in all the breast milk samples. In the human milk, CB-153 was the most dominant PCB congener (17-44% contribution to the sum PCB), closely followed by CB-138 (12-35%), CB-118 (4-12%), CB-180 (2-13%), CB-187 (3-13%), and CB-170 (1.5-10%). Levels of PBDEs (median: 3.0 ng/g lipid wt.) in human milk samples from the Philippines were similar to other Asian or European countries. BDE-47, -99, -100 and -153 were the major PBDE congeners. For HBCDs, the alpha-isomer was predominant followed by the gamma-HBCD isomer in the both locations. PBDE levels in human milk were significantly higher in the dumpsite (3.9 ng/g lipid wt.) than in the non-dump site (2.2 ng/g lipid wt.). PBDE concentrations (including BDE-209) were significantly higher (median: 70 ng/g hair) than those of PCBs (median: 30 ng/g hair) and HBCDs (median: 1.0 ng/g hair) in all the scalp hair samples. To our knowledge, this is the first report on HBCDs in human scalp hair. PBDE congeners in scalp hair were dominated by BDE-209 and BDE-47. On a congener basis, the levels of PBDEs found in scalp hair were higher than those in Spain (children and adults) and China (general people). PCB levels found in scalp hair were higher than those in Greece, Romania and Belgium, but lower than those in China. In this study, there were no significant differences in the concentration of PCBs and HBCDs in human milk; and PCBs, HBCDs and PBDEs in human scalp hair from the two different locations. No significant correlations were observed between PCBs, PBDEs and HBCDs levels and age of mothers in this study, which may be due to the small number of samples. Furthermore, there was no correlation between milk and hair levels for more persistent compounds (PCB-153, PCB-138, or BDE-47), and thus it is worthy to follow-up in future studies along with more number of samples. This is the first report to provide measurement data for PCBs, PBDEs and HBCDs in paired milk and hair of populations in the Philippines. (C) 2012 Elsevier B.V. All rights reserved.
  • Paromita Chakraborty, Gan Zhang, Sabine Eckhardt, Jun Li, Knut Breivik, Paul K.S. Lam, Shinsuke Tanabe, Kevin C. Jones
    Environmental Pollution 182 283 - 290 0269-7491 2013 [Peer-reviewed]
     Scientific journal 
    Atmospheric concentration of Polychlorinated biphenyls (PCBs) were measured on diurnal basis by active air sampling during Dec 2006 to Feb 2007 in seven major cities from the northern (New Delhi and Agra), eastern (Kolkata), western (Mumbai and Goa) and southern (Chennai and Bangalore) parts of India. Average concentration of Σ25PCBs in the Indian atmosphere was 4460 (±2200) pg/m-3 with a dominance of congeners with 4-7 chlorine atoms. Model results (HYSPLIT, FLEXPART) indicate that the source areas are likely confined to local or regional proximity. Results from the FLEXPART model show that existing emission inventories cannot explain the high concentrations observed for PCB-28. Electronic waste, ship breaking activities and dumped solid waste are attributed as the possible sources of PCBs in India. Σ25PCB concentrations for each city showed significant linear correlation with Toxicity equivalence (TEQ) and Neurotoxic equivalence (NEQ) values. © 2013 Elsevier Ltd. All rights reserved.
  • Akira Kubota, Kumiko Yoneda, Shinsuke Tanabe, Hisato Iwata
    Environmental Pollution 178 300 - 305 0269-7491 2013 [Peer-reviewed]
     Scientific journal 
    This study focuses on gender-specific accumulation features of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in common (great) cormorants (Phalacrocorax carbo) collected from Lake Biwa, Japan. Male cormorants showed a tendency to have higher levels of PCDD/DFs and DL-PCBs than did females. For PCDDs, the male-to-female concentration ratio (M/F ratio) for each congener significantly decreased with the liver-to-muscle concentration ratio (Li/Mu ratio). For PCDFs, there also was a weak negative relationship between Li/Mu ratio and M/F ratio. In contrast, for DL-PCBs, M/F ratios showed no correlation with Li/Mu ratios, but increased with an increase in lipophilicity. These results, together with observations from prior studies, suggest that congener-specific hepatic sequestration may be a factor limiting the maternal transfer of PCDDs and, to a lesser extent, PCDFs. Maternal transfer of DL-PCBs seems to favor more lipophilic congeners in the cormorants. © 2013 Elsevier B.V. All rights reserved.
  • Michinobu Kuwae, Narumi K. Tsugeki, Tetsuro Agusa, Kazuhiro Toyoda, Yukinori Tani, Shingo Ueda, Shinsuke Tanabe, Jotaro Urabe
    Science of the Total Environment 442 (1) 189 - 197 0048-9697 2013 [Peer-reviewed]
     Scientific journal 
    Concentrations of 18 elements, including Sb, In, Sn, and Bi, were measured in sediment cores from two pristine alpine lakes on Mount Hachimantai, northern Japan, representing the past 250years. Vertical variations in concentrations are better explained by atmospheric metal deposition than by diagenetic redistribution of Fe and Mn hydroxide and organic matter. Anthropogenic metal fluxes were estimated from 210Pb-derived accumulation rates and metal concentrations in excess of the Al-normalized mean background concentration before 1850. Anthropogenic fluxes of Sb and In showed gradual increases starting around 1900 in both lakes, and marked increases after 1980. Comparison of Sb/Pb and Pb stable isotope ratios in sediments with those in aerosols of China or northern Japan and Japanese source materials (recent traffic- and incinerator-derived dust) suggest that the markedly elevated Sb flux after 1980 resulted primarily from enhanced long-range transport in aerosols containing Sb and Pb from coal combustion on the Asian continent. The fluxes of In, Sn, and Bi which are present in Chinese coal showed increasing trends similar to Sb for both study lakes. This suggests that the same source although incinerators in Japan may not be ruled out as sources of In. The sedimentary records for the last 250years indicate that atmospheric pollution of Sb and In in East Asia have intensified during recent decades. © 2012 Elsevier B.V.
  • Narumi K. Tsugeki, Tetsuro Agusa, Shingo Ueda, Michinobu Kuwae, Hirotaka Oda, Shinsuke Tanabe, Yukinori Tani, Kazuhiro Toyoda, Wan-lin Wang, Jotaro Urabe
    ECOLOGICAL RESEARCH 27 (6) 1041 - 1052 0912-3814 2012/11 [Peer-reviewed]
     Scientific journal 
    Atmospheric dust has wide-reaching effects, not only influencing climate conditions, but also ecosystems. The eastern region of the Asian continent is one of the largest emitters of dust in the world, and recent economic growth in the region has been accompanied by an increase in anthropogenic emissions. However, the effects of increased Asian dusts on aquatic ecosystems are not well understood. We examined fossil pigments and zooplankton remains from Pb-210-dated sediments taken from high mountain lakes of Hourai-Numa and Hachiman-Numa, located in the Towada-Hachimantai National Park of Japan Islands, to uncover historical changes in the phyto-and zooplankton community over the past 100 years. Simultaneously, we measured the geochemical variables of TOC, TN, TP, delta C-13, delta N-15, and lead isotopes (Pb-207/Pb-206, Pb-208/Pb-206) in the sediments to identify environmental factors causing such changes. As a result, despite few anthropogenic activities in the watersheds, alpine lakes in Japan had increased algal and herbivore plankton biomasses by 3-6 fold for recent years depending on the surrounding terrestrial vegetation and landscape conditions. Biological and biogeochemical proxies recorded from the lake sediments showed that this eutrophication occurred after the 1990s when P deposition increased as a result of atmospheric loading of dust transported from the Asian continent. The continued increase of anthropogenically produced dust may therefore impart damaging impacts on mountain ecosystems even if they are protected from direct anthropogenic disturbances.
  • Haruhiko Nakata, Ryu-Ichi Shinohara, Yusuke Nakazawa, Tomohiko Isobe, Agus Sudaryanto, Annamalai Subramanian, Shinsuke Tanabe, Mohamad Pauzi Zakaria, Gene J. Zheng, Paul K. S. Lam, Eun Young Kim, Byung-Yoon Min, Sung-Ug We, Pham Hung Viet, Touch Seang Tana, Maricar Prudente, Donnell Frank, Gunnar Lauenstein, Kurunthachalam Kannan
    MARINE POLLUTION BULLETIN 64 (10) 2211 - 2218 0025-326X 2012/10 [Peer-reviewed]
     Scientific journal 
    We analyzed 68 green and blue mussels collected from Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Vietnam and the USA during 2003 and 2007, to elucidate the occurrence and widespread distributions of emerging pollutants, synthetic musks and benzotriazole UV stabilizers (BUVSs) in Asia-Pacific coastal waters. Synthetic musks and BUVSs were detected in mussels from all countries, suggesting their ubiquitous contamination and widespread distribution. High concentrations of musks and BUVSs were detected in mussels from Japan and Korea, where the levels were comparable or greater than those of PCBs, DDTs and PBDEs. Significant correlations were found between the concentrations of HHCB and AHTN, and also between the concentrations of UV-327 and UV-328, which suggest similar sources and compositions of these compounds in commercial and industrial products. To our knowledge, this is the first study of large-scale monitoring of synthetic musks and BUVSs in Asia-Pacific coastal waters. (C) 2012 Elsevier Ltd. All rights reserved,
  • Akifumi Eguchi, Kei Nomiyama, Gnanasekaran Devanathan, Annamalai Subramanian, Kesav A. Bulbule, Peethambaram Parthasarathy, Shin Takahashi, Shinsuke Tanabe
    ENVIRONMENT INTERNATIONAL 47 8 - 16 0160-4120 2012/10 [Peer-reviewed]
     Scientific journal 
    We determined the contamination status and accumulation profiles of polychlorinated biphenyls (PCBs), hydroxylated PCB congeners (OH-PCBs), polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs (OH-PBDEs), methoxylated PBDEs (MeO-PBDEs), and bromophenols (BPhs) in serum from e-waste recycling workers and residents near a coastal area in India. Residue levels of penta- to octa-chlorinated PCBs, penta- to octa-chlorinated OH-PCBs, 6MeO-BDE47, 6OH-BDE47, and 2,4,6-tri-BPh in serum from residents living near the coastal area were significantly higher than those in serum from e-waste recycling workers. Residue levels of tri- to tetra-chlorinated PCBs, tri- to tetra-chlorinated OH-PCBs. PBDEs. octa-brominated OH-PBDEs, and tetra-BPhs in serum from e-waste recycling workers were higher than those in serum from residents living near the coastal area. Principal component analysis revealed that residents living near the coastal area and e-waste recycling workers had different serum profiles of chlorinated and brominated compounds. (C) 2012 Elsevier Ltd. All rights reserved.
  • Tomohiko Isobe, Shohei P. Ogawa, Karri Ramu, Agus Sudaryanto, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 19 (8) 3107 - 3117 0944-1344 2012/09 [Peer-reviewed]
     Scientific journal 
    Hexabromocyclododecanes (HBCDs), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), and decabromodiphenyl ethane (DBDPE) used as alternatives for polybrominated diphenyl ethers (PBDEs) are also persistent in the environment as PBDEs. Limited information on these non-PBDE brominated flame retardants (BFRs) is available; in particular, there are only few publications on environmental pollution by these contaminants in the coastal waters of Asia. In this regard, we investigated the contamination status of HBCDs, BTBPE, and DBDPE in the coastal waters of Asia using mussels as a bioindicator. Concentrations of HBCDs, BTBPE, and DBDPE were determined in green (Perna viridis) and blue mussels (Mytilus edulis) collected from the coastal areas in Cambodia, China (mainland), SAR China (Hong Kong), India, Indonesia, Japan, Malaysia, the Philippines, and Vietnam on 2003-2008. BTBPE and DBDPE were analyzed using GC-MS, whereas HBCDs were determined by LC-MS/MS. HBCDs, BTBPE, and DBDPE were found in mussels at levels ranging from < 0.01 to 1,400, < 0.1 to 13, and < 0.3 to 22 ng/g lipid wt, respectively. Among the three HBCD diastereoisomers, alpha-HBCD was the dominant isomer followed by gamma- and beta-HBCDs. Concentrations of HBCDs and DBDPE in mussels from Japan and Korea were higher compared to those from the other Asian countries, indicating extensive usage of these non-PBDE BFRs in Japan and Korea. Higher levels of HBCDs and DBDPE than PBDEs were detected in some mussel samples from Japan. The results suggest that environmental pollution by non-PBDE BFRs, especially HBCDs in Japan, is ubiquitous. This study provides baseline information on the contamination status of these non-PBDE BFRs in the coastal waters of Asia.
  • Akira Kubota, Michio X. Watanabe, Eun-Young Kim, Kumiko Yoneda, Shinsuke Tanabe, Hisato Iwata
    ENVIRONMENTAL POLLUTION 168 131 - 137 0269-7491 2012/09 [Peer-reviewed]
     Scientific journal 
    To validate the outcome of the national regulation on dioxins emission implemented in 1999, this study investigated temporal trends of chlorinated dioxins and related compounds (DRCs) in liver of common cormorants (Phalacrocorax carbo) collected from Lake Biwa, Japan between 2001 and 2008, as a part of the "Survey on the State of Dioxins Accumulation in Wildlife" conducted by the Ministry of the Environment, Japan. We also measured a biomarker of DRCs exposure, the cytochrome P450 1A (CYP1A)-dependent O-dealkylation activity of alkoxyresorufins (AROD), including methoxy-, ethoxy-, pentoxy- and benzyloxy-resorufins in the samples over 2001-2007. Neither TEQ nor AROD activity showed any clear declining trend over the time period, although the emission of DRCs during the corresponding period was estimated to be apparently decreasing. Our data indicate that the concentration of recalcitrant DRCs in the cormorant during 2001-2008 was scarcely affected by the national regulation on dioxins emission. (c) 2012 Elsevier Ltd. All rights reserved.
  • Takaaki Itai, Daisuke Hayase, Yuika Hyobu, Sawako H. Hirata, Michio Kumagai, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 46 (11) 5789 - 5797 0013-936X 2012/06 [Peer-reviewed]
     Scientific journal 
    In December 2007, a mass mortality of isaza (Gymnogobius isaza), a goby fish m Lake Biwa, Japan, was observed under severe hypoxia. Considering the level of manganese and arsenic in the dead isaza during the event was much higher than that in live isaza, hypoxia-induced mobilization of manganese and arsenic and subsequent exposure could be the reason for this adverse effect. However, secondary accumulation of manganese and arsenic after the mortality event could not be ruled out To test this hypothesis, we conducted tissue distribution/speciation analysis and absorption tests on dead specimens All the results, particularly the limited absorption of arsenic in the absorption tests, indicated that the isaza were exposed to arsenic before the mortality event. Parallel to this, the geochemical behavior of manganese and arsenic in oxygen rich conditions (June) and oxygen poor conditions (December) was investigated to verify the mechanism of exposure. Considerable enrichment of manganese and arsenic in a thin surface layer of sediment was a common feature in all seven stations studied. In the water at the bottom of the lake, a clear increase of arsenite in December was observed, and the manganese level was several hundred times higher in both seasons than the average level of the lake. Although further verification is needed, the data provided here support exposure to manganese and arsenic under hypoxia.
  • Joon-Woo Kim, Tomohiko Isobe, Govindan Malarvannan, Agus Sudaryanto, Kwang-Hyeon Chang, Maricar Prudente, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 424 174 - 181 0048-9697 2012/05 [Peer-reviewed]
     Scientific journal 
    Seven compounds of benzotriazole ultraviolet stabilizers (BUVSs) were determined in house dust samples collected from a residential area (Malate: n = 17) and municipal dumping area (Payatas: n = 20) in the Philippines. Total concentrations of the 7 BUVSs in house dust ranged from ND (not detected) to 1020 ng/g in Malate and ND to 277 ng/g in Payatas. Among the target compounds, the most abundant BUVS was UV-234, with a median value of 84 ng/g (ND-813 ng/g) in Malate and 41 ng/g (ND-212 ng/g) in Payatas, respectively. Significantly higher concentrations of UV-326 (p<0.01) and UV-327 (p<0.05) were found in house dust samples from Malate than those from Payatas, suggesting that the household products are the major sources of contamination in the indoor microenvironment. The estimated daily intakes (EDIs) of BUVSs through house dust ingestion in the Philippines were two to four orders of magnitude lower than the guideline values. However. the EDI of 5 BUVSs for toddlers in this study was 5 times higher than those for adults, suggesting that toddlers are at higher risk. House dust may be an important exposure route of UV-234 (88%) and UV-326 (69%) in worst-case scenarios, which using high dust ingestion and worst-case exposure (P95). To our knowledge, this is the first comprehensive study on BUVSs in house dust samples from Asian developing countries and reporting the occurrence of UV-234 and UV-320 in dust samples. (c) 2012 Elsevier B.V. All rights reserved.
  • Kwadwo Ansong Asante, Tetsuro Agusa, Charles Augustus Biney, William Atuobi Agyekum, Mohammed Bello, Masanari Otsuka, Takaaki Itai, Shin Takahashi, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 424 63 - 73 0048-9697 2012/05 [Peer-reviewed]
     Scientific journal 
    To understand human contamination by multi-trace elements (TEs) in electrical and electronic waste (e-waste) recycling site at Agbogbloshie, Accra in Ghana, this study analyzed TEs and As speciation in urine of e-waste recycling workers. Concentrations of Fe, Sb, and Pb in urine of e-waste recycling workers were significantly higher than those of reference sites after consideration of interaction by age, indicating that the recycling workers are exposed to these TEs through the recycling activity. Urinary As concentration was relatively high, although the level in drinking water was quite low. Speciation analysis of As in human urine revealed that arsenobetaine and dimethylarsinic acid were the predominant As species and concentrations of both species were positively correlated with total As concentration as well as between each other. These results suggest that such compounds may be derived from the same source, probably fish and shellfish and greatly influence As exposure levels. To our knowledge, this is the first study on human contamination resulting from the primitive recycling of e-waste in Ghana. This study will contribute to the knowledge about human exposure to trace elements from an e-waste site in a less industrialized region so far scantly covered in the literature. (c) 2012 Elsevier B.V. All rights reserved.
  • Nguyen Tai Tue, Tran Dang Quy, Atsuko Amano, Hideki Hamaoka, Shinsuke Tanabe, Mai Trong Nhuan, Koji Omori
    WATER AIR AND SOIL POLLUTION 223 (3) 1315 - 1330 0049-6979 2012/03 [Peer-reviewed]
     Scientific journal 
    Historical profiles of trace element concentrations were reconstructed from two mangrove sediment cores collected within the Ba Lat Estuary (BLE), Red River, Vietnam. Chronologies of sediment cores were determined by the Pb-210 method, which showed that each respective sediment core from the south and north entrances of BLE provided a record of sediment accumulation spanning approximately 100 and 60 years. The profiles of Pb, Zn, Cu, Cr, V, Co, Sb, and Sn concentrations markedly increased from the years of the 1920s-1950s, and leveled out from 1950s-1980s, and then gradually decreased from 1980s to present. The profiles of Cd and Ag concentrations increased from 1920s-1940s, and then decreased from 1940s to present. The profile of Mo concentrations progressively increased from 1920s-1980s, then decreased to present. The Mn concentrations failed to show a clear trend in both sediment cores. Results from contamination factors, Pearson's correlation, and hierarchical cluster analysis suggest that the trace elements were likely attributed to discharge of untreated effluents from industry, domestic sewage, as well as non-point sources. Pollution Load Index (PLI) revealed levels higher than other mangrove sediment studies, and the long-term variations in PLI matched significant socioeconomic shifts and population growth in Vietnam. Geoaccumulation Index showed that mangrove sediments were moderately polluted by Pb and Ag, and from unpolluted to moderately polluted by Zn, Cu, and Sb. The concentrations of Pb, Zn, Cu, Cr, and Cd exceeded the threshold effect levels and effect range low concentrations of sediment quality guidelines, implying that the sediments may be occasionally associated with adverse biological effects to benthic organisms.
  • Ana C. A. Sousa, Isabel B. Oliveira, Filipe Laranjeiro, Shin Takahashi, Shinsuke Tanabe, Marina R. Cunha, Carlos M. Barroso
    MARINE POLLUTION BULLETIN 64 (2) 422 - 426 0025-326X 2012/02 [Peer-reviewed]
     Scientific journal 
    Organotin compounds (OTs) are ubiquitous in the marine environment and high concentrations (mu g g(-1) range) in sediments from different coastal areas around the world have been reported. However, few reports have described the OTs contamination status in the offshore and deep sea environment. This work investigated organotin levels in Nazare canyon for the first time. Levels of monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPT), triphenyltin (TPT), dioctyltin (DOT) and trioctyltin (TOT) were quantified in sediment samples from the upper flanks of the canyon and from the adjacent coastal area. TBT levels detected in the canyon flanks are about two to three orders of magnitude lower than those found in the coastal area. Nevertheless, when quantifiable. TBT levels in the canyon samples were higher than the Environmental Assessment Criteria set for TBT in sediments by the OSPAR Commission indicating that at those locations negative ecological impacts are likely to occur. (C) 2011 Elsevier Ltd. All rights reserved.
  • Gnanasekaran Devanathan, Annamalai Subramanian, Agus Sudaryanto, Shin Takahashi, Tomohiko Isobe, Shinsuke Tanabe
    ENVIRONMENT INTERNATIONAL 39 (1) 87 - 95 0160-4120 2012/02 [Peer-reviewed]
     Scientific journal 
    This study investigated the status of contamination of organohalogen compounds (OCs) such as polychlorinated biphenyls (PCBs) and brominated flame retardant (BFRs), including polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in human milk samples from several locations in India. The levels of OCs were significantly higher in the milk of mothers living in and near municipal dumping site than other locations indicating that the open dumping sites for municipal wastes act as potential sources of these contaminants in India. The PCB concentrations observed in this study tended to decrease compared to those in the matched locations reported previously, probably due to the restriction of technical PCB usage in India. PBDE levels in human milk were two to three folds lower than those of PCBs in all the sampling locations investigated. Congener profiles of PCBs and PBDEs were different between samples from the dumping site mothers and general populations in other areas suggesting the presence of region-specific sources and pathways. HBCDs were detected in human milk from only two sites, with much lower concentrations and detection frequencies compared to PCBs and PBDEs. When hazard quotients (HQs) of PCBs and PBDEs were estimated for infant health risk, the HQs in some milk samples from the dumping site exceeded the threshold value (HQ>1) of PCBs, indicating the potential risk for infants in the specific site. (C) 2011 Elsevier Ltd. All rights reserved.
  • Itai Takaaki, Kumagai Michio, Hyobu Yuika, Hayase Daisuke, Horai Sawako, Kuwae Michinobu, Tanabe Shinsuke
    GEOCHEMICAL JOURNAL 46 (6) E47 - E52 0016-7002 2012 [Peer-reviewed]
  • Tetsuro Agusa, Takashi Kunito, Nguyen Minh Tue, Vi Thi Mai Lan, Junko Fujihara, Haruo Takeshita, Tu Binh Minh, Pham Thi Kim Trang, Shin Takahashi, Pham Hung Viet, Shinsuke Tanabe, Hisato Iwata
    METALLOMICS 4 (1) 91 - 100 1756-5901 2012 [Peer-reviewed]
     Scientific journal 
    We investigated the association of As exposure and genetic polymorphism in glutathione S-transferase pi 1 (GSTP1) with As metabolism in 190 local residents from the As contaminated groundwater areas in the Red River Delta, Vietnam. Total As concentrations in groundwater ranged from <0.1 to 502 mu g l(-1). Concentrations of dimethylarsinic acid (DMA(V)), monomethylarsonic acid (MMA(V)), and arsenite (As(III)) in human urine were positively correlated with total As levels in the groundwater, suggesting that people in these areas may be exposed to As through the groundwater. The concentration ratios of urinary As(III) /arsenate (As(V)) and MMA(V) /inorganic As (IA; As(III) + As(V))(M/I), which are indicators of As metabolism, increased with the urinary As level. Concentration and proportion of As(III) were high in the wild type of GSTP1 Ile105Val compared with the hetero type, and these trends were more pronounced in the higher As exposure group (>56 mu g l(-1) creatinine in urine), but not in the lower exposure group. In the high As exposure group, As(III)/As(V) ratios in the urine of wild type of GSTP1 Ile105Val were significantly higher than those of the hetero type, while the opposite trend was observed for M/I. These results suggest that the excretion and metabolism of IA may depend on both the As exposure level and the GSTP1 Ile105Val genotype.
  • Joon-Woo Kim, Tomohiko Isobe, Kwang-Hyeon Chang, Atsuko Amano, Rommel H. Maneja, Peter B. Zamora, Fernando P. Siringan, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 159 (12) 3653 - 3659 0269-7491 2011/12 [Peer-reviewed]
     Scientific journal 
    Organophosphorus compounds (OPCs) and stable isotope ratios (delta C-13 and delta N-15) were determined in 58 fishes belonging to 20 species collected from Manila Bay, the Philippines. OPCs wore detected in most of the samples and found up to mu g/g lw (lipid weight) level, suggesting their ubiquitous presence in the coastal marine environment of the Philippines. Higher levels (>1000 ng/g lw) of total OPCs were determined in yellowstriped goatfish, silver sillago, tripletail wrasse and bumpnose trevally indicates either their active uptake from ambient water or lower metabolic capacity of these species. Levels of triphenyl phosphate (TPhP) in demersal species showed a positive correlation with delta N-15, indicating that TPhP was adsorbed onto the particle, settled down to the bottom sediment and accumulated through the benthic food web rather than the pelagic. Estimated dietary intake of OPCs in Man la Bay fishes were four to five orders of magnitude lower than the proposed reference dose (RfD). (C) 2011 Elsevier Ltd. All rights reserved.
  • Go Suzuki, Nguyen M. Tue, Sander van der Linden, Abraham Brouwer, Bart van der Burg, Martin van Velzen, Marja Lamoree, Masayuki Someya, Shin Takahashi, Tomohiko Isobe, Yuko Tajima, Tadasu K. Yamada, Hidetaka Takigami, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 45 (23) 10203 - 10211 0013-936X 2011/12 [Peer-reviewed]
     Scientific journal 
    We evaluated the applicability of combining in vitro bioassays with instrument analyses to identify potential endocrine disrupting pollutants in sulfuric acid-treated extracts of liver and/or blubber of high trophic-level animals. Dioxin-like and androgen receptor (AR) antagonistic activities were observed in Baikal seals, common cormorants, raccoon dogs, and finless porpoises by using a panel of rat and human cell-based chemical-activated luciferase gene expression (CALUX) reporter gene bioassays. On the other hand, no activity was detected in estrogen receptor alpha (ER alpha)-, glucocorticoid receptor (GR)-, progesterone receptor (PR)-, and peroxisome proliferator-activated receptor gamma 2 (PPAR gamma 2)-CALUX assays with the sample amount applied. All individual samples (n = 66) showed dioxin-like activity, with values ranging from 21 to 5500 pg CALUX-2,3,7,8-tetrachlorodibenzo-p-dioxin equivalent (TEQ)/g-lipid. Because dioxins are expected to be strong contributors to CALUX-TEQs, the median theoretical contribution of dioxins calculated from the result of chemical analysis to the experimental CALUX-TEQs was estimated to explain up to 130% for all the tested samples (n = 54). Baikal seal extracts (n = 31), but not other extracts, induced AR antagonistic activities that were 8-150 mu g CALUX-flutamide equivalent (FluEQ)/g-lipid. p,p'-DDE was identified as an important causative compound for the activity, and its median theoretical contribution to the experimental CALUX-FluEQs was 59% for the tested Baikal seal tissues (n = 25). Our results demonstrate that combining in vitro CALUX assays with instrument analysis is useful for identifying persistent organic pollutant-like compounds in the tissue of wild animals on the basis of in vitro endocrine disruption toxicity.
  • Tatsuya Kunisue, Aldfumi Eguchi, Hisato Iwata, Shinsuke Tanabe, Kurunthachalam Kannan
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 45 (23) 10140 - 10147 0013-936X 2011/12 [Peer-reviewed]
     Scientific journal 
    Thyroid hormones (THs) are essential for the regulation of growth and development in both humans and wildlife. Until recently, TH concentrations in the tissues of animals have been examined by immunoassay (IA) methods. IA methods are sensitive, but for TH analysis, they are compromised by a lack of adequate specificity. In this study, we determined the concentrations of six THs, L-thyroxine (T-4), 3,3',5-triiodo-L-thyronine (T-3), 3,3',5'-triiodo-L-thyronine (rT(3)), 3,5-diiodo-L-thyronine (3,5-T-2), 3,3'-diiodo-L-thyronine (3,3'-T-2), and 3-iodo-L-thyronine (3-T-1), in the serum of humans (n = 79) and wild Baikal seals (n = 37), by isotope ([C-13(6)]-T-4)dilution liquid chromatography (LC)-tandem mass spectrometry (MS/MS), and compared the TH levels with those measured by an electrochemiluminescent immunoassay (ECLIA) method. T-3 and T-4 were detected in all serum samples of both humans and Baikal seals, whereas T-1, 3,3'-T-2, and 3,5-T-2 were below the limit of detection (LOD). rT(3) was detected in Baikal seal sera at concentrations higher than T-3 in 28 seal samples, indicating an anomaly in deiodinase activity in Baikal seals. In humans, regression analyses of TH concentrations, measured by ECLIA and LC-MS/MS methods, showed significant correlations for T-4 (r = 0.852) and T-3 (r = 0.676; after removal of a serum sample with abnormal T-3 levels). In Baikal seals, a low correlation coefficient (r = 0.466) for T-4 levels and no correlation for T-3 levels (p = 0.093) were found between ECLIA and LC-MS/MS methods. These results suggest that interference by a nonspecific reaction against anti-T-3 and anti-T-4 antibodies used in the ECLIA can contribute to inaccuracies in TH measurement in Baikal seals. When the relationship between concentrations of THs in sera and dioxin-like toxic equivalents in blubber samples of Baikal seals (n = 19) was examined, a significantly negative correlation was found for serum T-4 levels measured by the LC-MS/MS method, but not for those measured by ECLIA. Thus, our results indicate that the LC-MS/MS method is more reliable and accurate for the elucidation of alteration in circulating TH levels in wildlife, as caused by environmental and physiological factors.
  • Kei Nomiyama, Akifumi Eguchi, Hazuki Mizukawa, Mari Ochiai, Satoko Murata, Masayuki Someya, Tomohiko Isobe, Tadasu K. Yamada, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 159 (12) 3364 - 3373 0269-7491 2011/12 [Peer-reviewed]
     Scientific journal 
    We determined the residue levels and patterns of hydroxylated polybrominated diphenyl ethers (OH-PBDEs), and related compounds, such as PBDEs, methoxylated PBDEs (MeO-PBDEs), and bromophenols (BPhs) in the blood of eleven cetacean species stranded along the Japanese coasts. The dominant OH- and MeO-PBDE isomers found in all cetaceans were 6OH-BDE47 and 6MeO-BDE47. Additionally, 2,4,6-triBPh was dominant isomer in all cetaceans. In contrast, specific differences in the distribution of para- and meta- OH-PBDE isomers and some BPhs (potential PBDEs metabolites) were found among the cetaceans. Residue levels of Sigma MeO-PBDEs and 6OH-BDE47 + 2'OH-BDE68, and 2,4,6-triBPh and 6OH-BDE47 + 2'OH-BDE68 showed a significant positive correlation. These results may suggest that the large percentages of OH-PBDEs, MeO-PBDEs and 2,4,6-triBPh might share common source (i.e. biosynthesis by marine organisms), or metabolic pathway in cetacean species. Significant correlations were found between the concentrations of BDE99 and 2,4,5-triBPh. This result suggested that 2,4,5-triBPh in cetaceans could be a metabolite of BDE99. (C) 2011 Elsevier Ltd. All rights reserved.
  • Junko Fujihara, Mikiko Soejima, Toshihiro Yasuda, Yoshiro Koda, Takashi Kunito, Hisato Iwata, Shinsuke Tanabe, Haruo Takeshita
    TOXICOLOGY AND APPLIED PHARMACOLOGY 256 (2) 174 - 178 0041-008X 2011/10 [Peer-reviewed]
     Scientific journal 
    Arsenic causes DNA damage and changes the cellular capacity for DNA repair. Genes in the base excision repair (BER) pathway influence the generation and repair of oxidative lesions. Single nucleotide polymorphisms (SNPs) in human 8-oxoguanine DNA glycosylase (hOGG1) Ser326Cys; apurinic/apyrimidinic endonuclease (APE 1) Asp148Glu; X-ray and repair and cross-complementing group 1 (XRCC1) Arg280His and Arg399Gln in the BER genes were analyzed, and the relationship between these 4 SNPs and the urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations of 100 Vietnamese population exposed to arsenic was investigated. Individuals with hOGG1 326Cys/Cys showed significantly higher urinary 8-OHdG concentrations than did those with 326 Ser/Cys and Ser/Ser. As for APE1 sp148Glu, heterozygous subjects showed significantly higher urinary 8-OHdG concentrations than did those homozygous for Asp/Asp. Moreover, global ethnic comparison of the allelic frequencies of the 4SNP5 was performed in 10 population and previous reported data. The mutant allele frequencies of hOGG1 Ser326Cys in the Asian populations were higher than those in the African and Caucasian populations. As for APE1 Asp148Glu, Caucasians showed higher mutant frequencies than those shown by African and Asian populations. Among Asian populations, the Bangladeshi population showed relatively higher mutant allele frequencies of the APE1 Asp148Glu polymorphism. This study is the first to demonstrate the existence of genetic heterogeneity in a worldwide distribution of SNPs (hOGG1 Ser326Cys, APE1 Asp148Glu, XRCC1 Arg280His, and XRCC1 Arg399Gln) in the BER genes. Published by Elsevier Inc.
  • Joon-Woo Kim, Tomohiko Isobe, Babu Rajendran Ramaswamy, Kwang-Hyeon Chang, Atsuko Amano, Todd M. Miller, Fernando P. Siringan, Shinsuke Tanabe
    CHEMOSPHERE 85 (5) 751 - 758 0045-6535 2011/10 [Peer-reviewed]
     Scientific journal 
    Benzotriazole ultraviolet stabilizers (BUVSs) used in plastic products, building materials and personal hygiene products were analyzed in fishes collected from Manila Bay, the Philippines. BUVSs were detected at ng g(-1) level in all the fish samples, indicating their ubiquitous contamination in coastal waters. Among the targeted eight BUVSs, UV-328 was predominantly found with a mean concentration of 34.2 ng g(-1) lipid weight, implying large scale production and use of this compound in the Philippines. High concentrations of Sigma BUVSs were found in bumpnose trevally (Carangoides hedlandensis), bluetail mullet (adult) (Valamugil buchanani), common ponyfish (Leiognathus equulus) and coral grouper (adult) (Epinephelus corallicola) indicating their active uptake and/or lower metabolic capacity to eliminate BUVSs. Among BUVSs, UV-P showed significant positive relationship (p < 0.05) between concentration and fish length (r = 0.29) and fish weight (r = 0.31). Levels of UV-P in demersal species had positive correlation with delta N-15, indicating that possibile sink of UV-P is bottom sediment in the bay, and ultimately accumulate through benthic food web rather than pelagic food web. To our knowledge, this is the first study on BUVSs distribution in fish from developing countries. (C) 2011 Elsevier Ltd. All rights reserved.
  • Kei Nomiyama, Yukiko Uchiyama, Satoko Horiuchi, Akifumi Eguchi, Hazuki Mizukawa, Sawako Horai Hirata, Ryota Shinohara, Shinsuke Tanabe
    CHEMOSPHERE 85 (3) 315 - 321 0045-6535 2011/10 [Peer-reviewed]
     Scientific journal 
    Information on accumulation of polychlorinated biphenyl metabolites (OH-PCBs) and hydroxylated polybrominated diphenyl ethers (OH-PBDEs) in the blood of marine fish is limited. The present study, we determined the residue levels and patterns of PCBs, OH-PCBs, PBDEs, OH-PBDEs and methoxylated PBDEs (MeO-PBDEs) in the blood collected from scalloped hammerhead shark (Sphyrna lewini) and Japanese amberjack (Seriola quinqueradiata), species of predatory fish at Japanese coastal waters. The predominant homologues found in Japanese amberjacks were mono- and di-chlorinated OH-PCBs, and scalloped hammerhead sharks were octa-chlorinated OH-PCBs. The predominant OH-PCB isomers were lower-chlorinated OH-PCBs such as 6OH-CB2 and 2'OH-CB9 in Japanese amberjacks. This result suggests that exposure of Japanese amberjacks to lower-chlorinated OH-PCBs might be from the ambient aquatic environment. In scalloped hammerhead sharks, 4,4'diOH-CB202, 4OH-CB201 and 4OH-CB146 were the predominant isomers accounting for approximately 60% of the total OH-PCBs. The predominant MeO-PBDE isomers were 6MeO-BDE47 followed by 2'MeO-BDE68 in both species. As for OH-PBDE isomers, 6OH-BDE47 was predominant followed by 2'OH-BDE68 in Japanese amberjacks and scalloped hammerhead sharks. Residue levels of Sigma MeO-PBDEs and Sigma OH-PBDEs showed a significant positive correlation (p = 0.029). This result suggests that MeO-PBDEs and OH-PBDEs share a common source or a metabolic pathway in fishes. Characteristic differences found in the profiles of OH-PCBs and OH-PBDEs in Japanese amberjack and scalloped hammerhead shark show the need for further studies on the differences in exposure profiles, metabolic capacities and toxic effects in fish. (C) 2011 Elsevier Ltd. All rights reserved.
  • Sawako Horai Hirata, Daisuke Hayase, Akifumi Eguchi, Takaaki Itai, Kei Nomiyama, Tomohiko Isobe, Tetsuro Agusa, Toshiyuki Ishikawa, Michio Kumagai, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 159 (10) 2789 - 2796 0269-7491 2011/10 [Peer-reviewed]
     Scientific journal 
    The present study measured the concentrations of 25 elements (Li, Mg, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, Pb and Bi) in the whole body of Isaza which is an endemic fish species to Lake Biwa, Japan, and compared the values in the specimens from the mass mortality Isaza (MMI) and normal fresh Isaza (NFI). The mean levels of Mn and total As (T-As) were relatively higher in MMI than in NFI. In the T-As, highly toxic inorganic As was detected in MMI. Moreover we found Mn and As concentrations in surface sediment were extremely high and temporally increased. From all these results, we could infer that the dissolution of Mn and As from surface sediment of Lake Biwa might have been one of the cause for the mass mortality of Isaza. (C) 2011 Elsevier Ltd. All rights reserved.
  • Babu Rajendran Ramaswamy, Joon-Woo Kim, Tomohiko Isobe, Kwang-Hyeon Chang, Atsuko Amano, Todd W. Miller, Fernando P. Siringan, Shinsuke Tanabe
    JOURNAL OF HAZARDOUS MATERIALS 192 (3) 1739 - 1745 0304-3894 2011/09 [Peer-reviewed]
     Scientific journal 
    Ultra high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) determination of four paraben preservatives (methyl, ethyl, propyl and butyl) and two antimicrobial agents (triclosan and triclocarban) belonging to personal care products (PCPs) in 20 species of fish from Manila Bay (Philippines) was performed. Detection of PCPs with greater frequency indicates the ubiquitous contamination of Manila Bay. Concentrations of total paraben were one order of magnitude higher than the antimicrobials in almost all fish, except in Stolephorus indicus and Leiognathus equulus. A positive correlation was observed between parabens concentration and fish length (r =0.31-0.49; p <0.05 to <0.001) and fish weight (r = 0.28-0.49; p< 0.05 to <0.001), but not for the antimicrobials. The estimated dietary exposure values of the four parabens in the Philippines through fish is four orders of magnitude lower than the acceptable daily intake (AD!) of 10 mg/kg/day, but the values of antimicrobials are just half of the ADI of TCS. To our knowledge, this is the first report of PCPs contamination in fish from Philippines. (C) 2011 Elsevier B.V. All rights reserved.
  • Shusaku Hirakawa, Daisuke Imaeda, Kei Nakayama, Masayuki Udaka, Eun-Young Kim, Tatsuya Kunisue, Masako Ogawa, Tomonari Matsuda, Saburo Matsui, Evgeny A. Petrov, Valeriy B. Batoev, Shinsuke Tanabe, Hisato Iwata
    AQUATIC TOXICOLOGY 105 (1-2) 89 - 99 0166-445X 2011/09 [Peer-reviewed]
     Scientific journal 
    We have previously indicated that accumulation of chlorinated dioxins and related compounds (DRCs) induced cytochrome P450 (CYP) 1A1, 1A2 and 1B1 isozymes in the liver of wild Baikal seals (Pusa sibirica). Here we attempt to assess the potential effects of DRCs triggered by the induction of these CYP1 isozymes in this species, using an integrative approach, combining gene expression monitoring and biochemical assays. To screen genes that may potentially respond to the exposure of DRCs, we constructed a custom cDNA oligo array that can target mRNAs in Baikal seals, and monitored hepatic mRNA expression levels in the wild population. Correlation analyses between the hepatic total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) and mRNA levels supported our previous findings that high accumulation of DRCs induces the transcription of CYP1A1, CYP1A2 and CYP1B1 genes. In addition, our integrative assessment indicated that the chronic exposure to DRCs may alter the hepatic transcript levels of genes related to oxidative stress, Fe ion homeostasis, and inflammatory responses. The expression levels of CYP1A2 showed significant positive correlations with levels of malondialdehyde, a biomarker of lipid peroxidation, and of etheno-dA, a DNA adduct, suggesting that the lipid peroxidation may be enhanced through the production of reactive oxygen species (ROS) triggered by CYP1A2 induction. Moreover, there was a positive correlation between heme oxygenase activities and malondialdehyde levels, suggesting the prompted hems degradation by ROS. Fetuin-A levels, which are suppressed by inflammation, showed a significant negative correlation with TEQ levels, and hepcidin levels, which are conversely increased by inflammation, had significant positive correlations with malondialdehyde and etheno-dA levels, implying the progression of inflammation by DRC-induced oxidative stress. Taken together, we propose here that wild Baikal seals may suffer from effects of chronic exposure to DRCs on the induction of CYP1 isozymes, followed by increased oxidative stress, heme degradation and inflammation. (C) 2011 Elsevier B.V. All rights reserved.
  • Sokichi Takagi, Fumie Adachi, Keiichi Miyano, Yoshihiko Koizumi, Hidetsugu Tanaka, Isao Watanabe, Shinsuke Tanabe, Kurunthachalam Kannan
    WATER RESEARCH 45 (13) 3925 - 3932 0043-1354 2011/07 [Peer-reviewed]
     Scientific journal 
    Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) have been recognized as global environmental pollutants. Although PFOS and PFOA have been detected in tap water from Japan and several other countries, very few studies have examined the fate, especially removal, of perfluorinated compounds (PFCs) in drinking water treatment processes. In this study, we analyzed PFOS and PFOA at every stages of drinking water treatment processes in several water purification plants that employ advanced water treatment technologies. PFOS and PFOA concentrations did not vary considerably in raw water, sand filtered water, settled water, and ozonated water. Sand filtration and ozonation did not have an effect on the removal of PFOS and PFOA in drinking water. PFOS and PFOA were removed effectively by activated carbon that had been used for less than one year. However, activated carbon that had been used for a longer period of time (>1 year) was not effective in removing PFOS and PFOA from water. Variations in the removal ratios of PFOS and PFOA by activated carbon were found between summer and winter months. (C) 2011 Elsevier Ltd. All rights reserved.
  • Kwadwo Ansong Asante, Sam Adu-Kumi, Kenta Nakahiro, Shin Takahashi, Tomohiko Isobe, Agus Sudaryanto, Gnanasekaran Devanathan, Edith Clarke, Osmund Duodu Ansa-Asare, Stephen Dapaah-Siakwan, Shinsuke Tanabe
    ENVIRONMENT INTERNATIONAL 37 (5) 921 - 928 0160-4120 2011/07 [Peer-reviewed]
     Scientific journal 
    Human exposure to polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) was evaluated in Ghana using breast milk samples collected in 2004 and 2009. Mean levels and ranges of PBDEs (4.5; 0.86-18 ng/g lw) and PCBs (62; 15-160 ng/g lw) observed in the present study were unexpectedly high, in spite of the fact that Ghana is a non-industrialized country when compared with many of the Asian and European countries. Significant increases were found in the concentrations of PCBs and PBDEs over the years, while no significant increase was observed for HBCDs. Estimated hazard quotient (HQ) showed that all the mothers had HQ values exceeding the threshold of 1 for PCBs, indicating potential health risk for their children. PCBs in dirty oils and obsolete equipment should be of concern as potential sources in Ghana, and e-waste recycling with little or no experience in safe handling could be a threat to this sub-region noted for unregulated disposal of e-waste. The results may point towards an increase in trends in human milk in Ghana, especially in the larger cities but further analysis would be required to confirm this upward trend in levels. This is the first study to report BFRs in human breast milk from Africa, and undoubtedly from Ghana. (C) 2011 Elsevier Ltd. All rights reserved.
  • Emiko Nakazawa, Tokutaka Ikemoto, Akiko Hokura, Yasuko Terada, Takashi Kunito, Takahito Yamamoto, Tadasu K. Yamada, Fernando C. W. Rosas, Gilberto Fillmann, Shinsuke Tanabe, Izumi Nakai
    JOURNAL OF ENVIRONMENTAL MONITORING 13 (6) 1678 - 1686 1464-0325 2011/06 [Peer-reviewed]
     Scientific journal 
    The chemical form of Ag in the livers of five species of marine mammals was examined using X-ray absorption fine structure (XAFS) and X-ray fluorescence (XRF) spectroscopies. The XAFS analysis suggested that Ag(2)Se was present in the livers of the Franciscana dolphin (Pontoporia blainvillei), Dall's porpoise (Phocoenoides dalli), and Baird's beaked whale (Berardius bairdii), whereas Ag(2)S was present in the livers of the striped dolphin (Stenella coeruleoalba) and pygmy killer whale (Feresa attenuata). XRF spectroscopy results revealed that the distribution patterns of Ag and Se in a thin section of the liver of the Franciscana dolphin were the same; this also implied that Ag was associated with Se in the liver. Thus, the interaction of Ag with Se or S may offer significant protection against the toxicity of Ag in marine mammals. The formation of either Ag(2)Se or Ag(2)S might depend on the Hg levels in the liver. Ag(2)Se was observed in liver samples with relatively high Ag/Hg ratio, whereas liver samples with low Ag/Hg ratio contained Ag(2)S.
  • Joon-Woo Kim, Babu Rajendran Ramaswamy, Kwang-Hyeon Chang, Tomohiko Isobe, Shinsuke Tanabe
    JOURNAL OF CHROMATOGRAPHY A 1218 (22) 3511 - 3520 0021-9673 2011/06 [Peer-reviewed]
     Scientific journal 
    A multiresidue analytical method for the determination of emerging pollutants belonging to personal care products (PCPs) (antimicrobials, preservatives), benzotriazole UV stabilizers (BUVSs) and organophosphorus compounds (OPCs) in fish has been developed using high speed solvent extraction (HSSE) followed by silica gel clean up and ultra fast liquid chromatography coupled with tandem mass spectrometry (UFLC-MS/MS) analysis. Developed extraction and clean up method yielded good recovery (>70%) for all the four groups of emerging pollutants, i.e. antimicrobials (78.5-85.6%), preservatives (85.0-89.4%), BUVSs (70.9-112%) and OPCs (81.6-114%; except for TEP - 68.9% and TPeP - 58.1%) with RSDs ranging from 0.7 to 15.4%. Intra- and inter-day repeatabilities were less than 19.8% and 19.0%, respectively at three spiked levels. The concentrations were given in lipid weight (lw) basis, and the method detection limits were achieved in the lowest range of 0.001-0.006 ng g(-1) for two antimicrobials, 0.001-0.015 ng g(-1) for four preservatives, 0.0002-0.009 ng g(-1) for eight BUVSs and 0.001-0.014 ng g(-1) for nine OPCs. Finally, the method was successfully validated as a simple and fast extraction method for the determination of 23 compounds belonging to PCPs, BUVSs and OPCs and applied to the analysis of three species of fish from Manila Bay, the Philippines. Concentrations ranged from 27 to 278 ng g(-1) for antimicrobials, 6.61 to 1580 ng g(-1) for paraben preservatives, <MDL (method detection limit) to 179 ng g(-1) for BUVSs and ND (not detected) to 266 ng g(-1) for OPCs suggesting the ubiquitous contamination by these emerging pollutants in Manila Bay. This is the first method developed for the determination of triclocarban, four paraben preservatives and four BUVSs, in fish. (C) 2011 Elsevier B.V. All rights reserved.
  • Tetsuro Agusa, Shin-ya Yasugi, Asami Iida, Tokutaka Ikemoto, Yasumi Anan, Thijs Kuiken, Albert D. M. E. Osterhaus, Shinsuke Tanabe, Hisato Iwata
    MARINE POLLUTION BULLETIN 62 (5) 963 - 975 0025-326X 2011/05 [Peer-reviewed]
     Scientific journal 
    Body distribution and growth- and nutritional status-dependent accumulation of 21 trace elements were investigated in harbor seals (Phoca vitulina) stranded in the North Sea coast in 2002. Higher concentrations and burdens of Mn, Se, Mo, Ag, Sn, Hg, and Bi in the liver, Cd in the kidney, As in the blubber, and Co, Sr, and Ba in the bone were observed. Significant positive correlations of hepatic Se, Mo, Ag, Cd, Sn, Hg, Tl, and Bi with standard body length were found, while significant negative relationships were detected for Mn, As, Rb, Sr, and Sb in the liver. Concentrations of Co, Se, Sr, Sn, Hg, and Bi in the liver, V. Sr, Ag, Sn, and Hg in the kidney, V. Mn, Co, Rb, Sr, Sn, Ba, and Pb in the blubber increased with decreasing blubber thickness of harbor seals, indicating enrichment of these elements in the target tissue by emaciation. (C) 2011 Elsevier Ltd. All rights reserved.
  • Atsuko Amano, Michinobu Kuwae, Tetsuro Agusa, Koji Omori, Hidetaka Takeoka, Shinsuke Tanabe, Takashige Sugimoto
    MARINE ENVIRONMENTAL RESEARCH 71 (4) 247 - 256 0141-1136 2011/05 [Peer-reviewed]
     Scientific journal 
    This study determined the factors contributing to the spatial distribution of 14 metal concentrations in the surface sediments of Beppu Bay on the basis of comparisons of the organic geochemical properties and environmental parameters through principal component analysis (PCA) and redundancy analysis (RDA). The results of PCA and RDA showed that the concentrations of V. Cr, Co, and As were closely related to the distances between the sampling sites and the Oita River. This indicated that these metals originated from the river's drainage area. The Mn, Cu, Mo, and Cd concentrations were related to the water depth. These results indicated that the Mo. Cd, and Cu deposition processes were controlled by oxygen depletion, and that these elements accumulated in the deeper parts of the bay under anoxic conditions. (C) 2011 Elsevier Ltd. All rights reserved,
  • Muhammad Ilyas, Agus Sudaryanto, Iwan Eka Setiawan, Adi Slamet Riyadi, Tomohiko Isobe, Shohei Ogawa, Shin Takahashi, Shinsuke Tanabe
    CHEMOSPHERE 83 (6) 783 - 791 0045-6535 2011/04 [Peer-reviewed]
     Scientific journal 
    In this study, soil contamination by PCBs, PBDEs, HBCDs and two novel BFRs such as 1,2-bis-(2,4,6-tribromopenoxy) ethane (BTBPE) and decabromodiphenyl ethane (DBDPE) in various locations such as industrial, urban, rural, dumping site and agricultural areas of Surabaya, Indonesia has been characterized in order to evaluate their contamination status, profiles, potential sources, fate and behavior. Range and median concentrations of PCBs, PBDEs, HBCDs, BTBPE and DBDPE were ND - 9.6(1.2), 0.069 - 24(7.4). ND - 1.8 (0.48), ND - 1.7 (0.14) and ND - 7.6 (2.2) ng g(-1) dw, respectively. Industrial, urban and dumping areas were inventoried as the main sources of these pollutants. Decreasing gradient levels were observed for these contaminants from industrial district, urban, dumping site, rural and agricultural areas, in that order. Furthermore, organic carbon contents and proximity to the point sources were found as the major controlling factors. Contaminant profiles were characterized by the predominance of hexa-, hepta- and penta-homologues for PCBs; deca-, nona- and octa- for PBDEs and a-isomer for HBCDs. Product mixtures such as Ar1260/KC600 and Ar1254/KC500 for PCBs, deca- and octa-BDEs for PBDEs were the possible common formulations used in study area. To our knowledge, this is a first comprehensive study on characterization of soil contamination by PCBs, PBDEs and HBCDs together with two novel BFRs in a highly industrialized city located in tropical region. This study provides baseline information for establishing national monitoring programs in Indonesia. (C) 2011 Elsevier Ltd. All rights reserved.
  • Joon-Woo Kim, Kwang-Hyeon Chang, Tomohiko Isobe, Shinsuke Tanabe
    JOURNAL OF TOXICOLOGICAL SCIENCES 36 (2) 247 - 251 0388-1350 2011/04 [Peer-reviewed]
     Scientific journal 
    Benzotriazole ultraviolet stabilizers (BUVSs) enter aquatic environments either directly, via wash-off from skin and clothes during water recreational activities, or indirectly, via discharges of sewage and swimming pool waters. Their potentially toxic effects on biota, particularly aquatic organisms, are of considerable concern. However, not much information on their toxicity to aquatic organisms is available. In the present study, we investigated the acute toxicity of selected BUVSs on a freshwater crustacean (Daphnia pulex) for the first time. The 24 and 48-hr median lethal concentration (LC50) values of UV-571 for D. pulex were estimated to be 6.35 (5.08-8.39) and 2.59 (2.04-3.38) mg/l, respectively. No acute toxicity effects were observed up to 10 mg/l for other BUVSs such as UV-9, -320, -326, -327, -328, -329, and -360. Although acute toxicities of targeted BUVSs were not high, further long-term studies are required to fully assess the effects on growth and reproduction by these compounds on aquatic biota because of their bioaccumulative characteristics.
  • Akira Kubota, John J. Stegeman, Jared V. Goldstone, David R. Nelson, Eun-Young Kim, Shinsuke Tanabe, Hisato Iwata
    COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY 153 (3) 280 - 289 1532-0456 2011/04 [Peer-reviewed]
     Scientific journal 
    Cytochrome P450 CYP2 family enzymes are important in a variety of physiological and toxicological processes. CYP2 genes are highly diverse and orthologous relationships remain clouded among CYP2s in different taxa. Sequence and expression analyses of CYP2 genes in diapsids including birds and reptiles may improve understanding of this CYP family. We sought CYP2 genes in a liver cDNA library of the common cormorant (Phalacrocorax carbo), and in the genomes of other diapsids, chicken (Gallus gallus), zebra finch (Taeniopygia guttata), and anole lizard (Anolis carolinensis), for phylogenetic and/or syntenic analyses. Screening of the cDNA library yielded four CYP2 cDNA clones that were phylogenetically classified as CYP2C45, CYP2J25, CYP2AC1, and CYP2AF1. There are numerous newly identified diapsid CYP2 genes that include genes related to the human CYP2Cs, CYP2D6, CYP2G2P, CYP2J2, CYP2R1, CYP2U1, CYP2W1, CYP2AB1P, and CYP2AC1P. Syntenic relationships show that avian CYP2Hs are orthologous to CYP2C62P in humans. CYP2C23 in rats, and Cyp2c44 in mice, and suggest that avian CYP2Hs, along with human CYP2C62P and mouse Cyp2c44, could be renamed as CYP2C23, based upon the nomenclature rules. Analysis of sequence and synteny identifies cormorant and finch CYPs that are apparent orthologs of phenobarbital-inducible chicken CYP2C45. Transcripts of all four cormorant CYP2 genes were detected in the liver of birds from Lake Biwa, Japan. The transcript levels bore no significant relationship to levels of chlorinated organic pollutants in the liver, including polychlorinated biphenyls and dichlorodiphenyltrichloroethane and its metabolites. In contrast, concentrations of perfluorooctane sulfonate and perfluorononanoic acid were negatively correlated with levels of CYP2C45 and/or CYP2J25, suggesting down-regulation of expression by these environmental pollutants. This study expands our view of the phylogeny and evolution of CYP2s, and provides evolutionary insight into the chemical regulation of CYP2 gene expression in diapsids including birds. (C) 2010 Elsevier Inc. All rights reserved.
  • Eun-Young Kim, Tomoko Suda, Shinsuke Tanabe, Valeriy B. Batoev, Evgeny A. Petrov, Hisato Iwata
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 45 (4) 1652 - 1658 0013-936X 2011/02 [Peer-reviewed]
     Scientific journal 
    To evaluate the sensitivity and responses to dioxins and related compounds (DRCs) via aryl hydrocarbon receptor (AHR) in Baikal seals (Pusa sibirica), we constructed an in vitro reporter gene assay system. Baikal seal AHR (BS AHR) expression plasmid and a reporter plasmid containing CYP1A1 promoter were transfected in COS-7 cells. The cells were treated with six representative congeners, and dose-dependent responses were obtained for all the congeners. EC(50) values of 2,3,7,8-TCDD, 1,2,3,7,8-PeCDD, 2,3,7,8-TCDF, 2,3,4,7,8-PeCDF, and PCB126 were found to be 0.021, 1.8, 0.16, 2.4, and 2.5 nM, respectively. As the response did not reach the maximal plateau, EC(50) value for PCB118 could not be obtained. The TCDD-EC(50) for BS AHR was as high as that for dioxin sensitive C57BL/6 mouse AHR. The in vitro dose responses were further analyzed following an established systematic framework and multiple (20, 50, and 80%) relative potencies (REPs) to the maximum TCDD response. The estimates revealed lower REP ranges (20-80%) of PeCDD and PeCDF for BS AHR than for mouse AHR. Average of the 20, 50, and 80% REPs was designated as Baikal seal specific TCDD induction equivalency factor (BS IEF). The BS LEFs of PeCDD, TCDF, PeCDF, PCB126, and PCB118 were estimated as 0.010, 0.018, 0.0078, 0.0059, and 0.00010, respectively. Total TCDD induction equivalents (IEQs) that were calculated using BS IEFs and hepatic concentrations in wild Baikal seals corresponded to only 12-31% of 2005 WHO TEF-derived TEQs. Nevertheless, about 50% of Baikal seals accumulated IEQs over the TCDD-EC(50) obtained in this study. This assessment was supported by the enhanced CYP1A1 mRNA expression found in 50% of the specimens contaminated over the TCDD-EC(50). These findings suggest that the IEFs proposed from this in vitro assay could be used to predict AHR-mediated responses in wild seals.
  • Junko Fujihara, Masanori Hasegawa, Rie Kanai, Tetsuro Agusa, Hisato Iwata, Shinsuke Tanabe, Toshihiro Yasuda, Seiji Yamaguchi, Haruo Takeshita
    FORENSIC TOXICOLOGY 29 (1) 65 - 68 1860-8965 2011/01 [Peer-reviewed]
     Scientific journal 
    Arsenic trioxide (ATO) is an effective agent for acute promyelocytic leukemia (APL). In this study, the concentrations of dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), As (V), As (III), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in urine and/or serum of a 4-year-old APL patient were followed during ATO treatment. In comparison with a similar analysis previously published for an 85-year-old APL patient, the levels of arsenic compounds and the percentages of MMA and DMA in the present child patient were lower than those of the old patient. Significant positive correlation of 8-OHdG was observed only with DMA, and not with other arsenic compounds. These results are quite different from those of our previous study on an old APL patient during ATO treatment. When arsenic poisoning is diagnosed, it seems important to take into account the differences in the arsenic metabolism according to the ages of subjects. This study is the first to show the relationship between the levels of 8-OHdG and arsenic compounds in urine of a child APL patient treated with ATO.
  • Tomohiko Isobe, Tomoko Oshihoi, Hiroki Hamada, Kei Nakayama, Tadasu K. Yamada, Yuko Tajima, Masao Amano, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 63 (5-12) 564 - 571 0025-326X 2011 [Peer-reviewed]
     Scientific journal 
    Contamination status of brominated flame retardants (BFRs) and persistent organic pollutants (POPs) in blubber of finless porpoises (Neophocaena phocaenoides) stranded along the coasts of Seto Inland Sea and Omura Bay in Japan were investigated. Levels of PCBs, DDTs and CHLs were significantly higher than those of HCHs, HCB, PBDEs and HBCDs. Concentrations of PBDEs and HBCDs, as well as organochlorine compounds in males increased with body length (p < 0.05). Among 14 PBDE congeners analyzed, BDE-47 was the predominant, which is similar to those generally reported in biota. PBDEs, HBCDs and PCBs showed no obvious temporal trend in concentrations during the study period, suggesting continuous environmental release of these chemicals. On the other hand, levels of DDT, CHLs and HCHs have decreased. Concentrations of PCBs in liver trematode infected individuals were significantly higher than those in not infected individuals, implying there could be a relationship between contaminant levels and parasitic infection. (C) 2011 Elsevier Ltd. All rights reserved.
  • Govindan Malarvannan, Shin Takahashi, Tokutaka Ikemoto, Tomohiko Isobe, Tatsuya Kunisue, Agus Sudaryanto, Toshihiko Miyagi, Masaru Nakamura, Shigeki Yasumura, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 63 (5-12) 541 - 547 0025-326X 2011 [Peer-reviewed]
     Scientific journal 
    Two species of fishes (n =52; tilapia and mullet) from industrialized and urbanized areas of Okinawa Island (Manko-Noha river, Hija river and Shikaza river) and from a remote area of Ishigaki Island (Anparu mudflat), Japan were collected between August 2005 and July 2006, and analyzed for five organochlorine compounds (OCs), viz., DDTs, PCBs, CHLs, HCHs and HCB. Concentrations and the contamination patterns of OCs in fishes varied between locations. Considerable residue levels of OCs, especially CHLs and DDTs were found in both fishes from the main Okinawa Island. These levels were relatively higher than the reported values for seafood from Japanese coasts, indicating that even now pollution sources of these contaminants still exist in this region. On the other hand, lower concentrations of OCs were detected in fishes from Ishigaki Island waters than those of other Japanese coastal waters, suggesting that this region is less contaminated by OC contaminants. (C) 2011 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Kumiko Nomura, Takashi Kunito, Yasumi Anan, Hisato Iwata, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 63 (5-12) 489 - 499 0025-326X 2011 [Peer-reviewed]
     Scientific journal 
    Nineteen trace elements were determined in liver, muscle, kidney, gonads, and hair of 18 harp seals (Phoca groenlandica) from Pangnirtung in the Baffin Island, Canada. Concentrations of V. Mn, Fe, Cu, Mo, Ag, and Hg in the liver, Co, Cd, and Tl in the kidney, and Ba and Pb in the hair were significantly higher than those in other tissues. Significant positive correlations between Hg concentrations in the hair, and liver, kidney and testis imply usefulness of the hair sample for non-destructive monitoring of Hg in the harp seals. It is suggested that whereas Hg preferentially accumulates in the liver, the accumulation in other tissues is induced at higher hepatic Hg levels. In contrast, Se may not be accumulated in other tissues compared with the liver even at higher hepatic Hg levels because of the presence of excess Se for Hg detoxification in other tissues (C) 2011 Elsevier Ltd. All rights reserved.
  • Govindan Malarvannan, Shin Takahashi, Tomohiko Isobe, Tatsuya Kunisue, Agus Sudaryanto, Toshihiko Miyagi, Masaru Nakamura, Shigeki Yasumura, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 63 (5-12) 172 - 178 0025-326X 2011 [Peer-reviewed]
     Scientific journal 
    Three species of sea turtles (green. hawksbill and loggerhead turtles) stranded along the coasts or caught (by-catch) around Ishigaki Island and Kochi, Japan were collected between 1998 and 2006 and analyzed for six organohalogen compounds viz., PBDEs, PCBs, DDTs, CHLs, HCHs and HCB. The present study is the first and foremost to report the occurrence of organohalogen compounds in the sea turtles from Japan. Among the compounds analyzed, concentrations of PCBs, DDTs and CHLs were the highest in all the turtle samples. PBDEs were ubiquitously present in all the turtle species. Comparing with the other two species, concentrations of organohalogens in green turtle were relatively low and decreasing trend in the concentrations were noted with increasing carapace length. Concentrations of OCs in sea turtles from the coasts of Ishigaki Island and Kochi were relatively low as compared to those from other locations in the world. (C) 2011 Elsevier Ltd. All rights reserved.
  • Nguyen Phuc Cam Tu, Tetsuro Agusa, Nguyen Ngoc Ha, Bui Cach Tuyen, Shinsuke Tanabe, Ichiro Takeuchi
    MARINE POLLUTION BULLETIN 63 (5-12) 124 - 134 0025-326X 2011 [Peer-reviewed]
     Scientific journal 
    We performed stable carbon and nitrogen-guided analyses of biomagnification profiles of arsenic (As) species, including total As, lipid-soluble As, eight water-soluble As compounds (arsenobetaine (AB), arsenocholine (AC), tetramethylarsonium ion (TETRA), trimethylarsine oxide (TMAO), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), arsenate (As[V]), and arsenite (As[III])), and non-extracted As in a tropical mangrove ecosystem in the Ba Ria Vung Tau, South Vietnam. Arsenobetaine was the predominant As species (65-96% of water-soluble As). Simple linear regression slopes of log-transformed concentrations of total As, As fractions or individual As compounds on stable nitrogen isotopic ratio (delta N-15) values are regarded as indices of biomagnification. In this ecosystem, lipid-soluble As (slope, 0.130) and AB (slope, 0.108) were significantly biomagnified through the food web; total As and other water-soluble As compounds were not. To our knowledge, this is one of the first reports on biomagnification profiles of As compounds from a tropical mangrove ecosystem. (C) 2011 Elsevier Ltd. All rights reserved.
  • Tashiro, Y, Ogura, G, Kunisue, T, Tanabe, S
    Japanese Journal of Zoo and Wildlife Medicine 16 (1) 65 - 70 2011 [Peer-reviewed]
  • Akifumi Eguchi, Tomohiko Isobe, Karri Ramu, Shinsuke Tanabe
    INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY 91 (4) 348 - 356 0306-7319 2011 [Peer-reviewed]
     Scientific journal 
    An analytical method for higher brominated congeners of polybrominated diphenyl ethers (PBDEs) was optimised using a gas chromatograph equipped with an electron impact ionisation-quadrupole mass spectrometer (GC-EI-qMS) and five native PBDEs and three (13)C(12)-labelled congeners in biological and environmental samples (mussels, sediment, dust). In the optimised instrumental conditions, abundance and repeatability improved with increase in temperature of the ion source. The instrumental detection limits (IDLs) for BDE-196, BDE-197, BDE-206, BDE-207 and BDE-209 were 0.1, 0.1, 0.2, 0.3 and 0.6 pg, respectively. When compared to the previous reports, the IDLs were the same as for electron capture negative ionisation (ECNI) or EI-double focusing magnetic sector (EI-Sector) mass spectrometer, indicating that sensitive determination could be achieved using a conventional GC-EI-qMS. Validation of the method was carried out by the analysis of reference materials and mussel samples. We confirmed that the concentrations quantified using this method was in the range of reported values for reference materials. Similar concentrations were found in mussels, which were analysed previously by our group. Thus, we conclude that a conventional GC-EI-qMS can be applied for analysis of higher brominated PBDEs in various environmental and biota matrices.
  • Tetsuro Agusa, Kozue Takagi, Todd W. Miller, Reiji Kubota, Yasumi Anan, Hisato Iwata, Shinsuke Tanabe
    ENVIRONMENTAL CHEMISTRY 8 (1) 19 - 29 1448-2517 2011 [Peer-reviewed]
     Scientific journal 
    We analysed arsenic (As) compounds in the stomach and intestine contents, bile and urine of green (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) to understand As accumulation through intake and excretion. Stable isotopes of delta N-15 and delta C-13 were also measured for understanding the feeding behaviour dependent accumulation of As. Major As species in gastrointestinal contents were unknown water-soluble As, followed by unextracted As. Concentrations of AB and DMA in the tissues were higher than those in the stomach contents (prey items), indicating high bioaccumulation of these arsenicals. In green turtles, AB concentration was high in bile and increased throughout the gastrointestinal tract, suggesting significant biliary excretion of AB. delta N-15 was positively correlated with AB level in green turtles, whereas a negative relationship between residual As and delta N-15 was observed in hawksbill turtles. This study indicates feeding behaviour-dependent accumulation of As compounds in both turtle species for the first time.
  • Muhammad Ilyas, Agus Sudaryanto, Iwan Eka Setiawan, Adi Slamet Riyadi, Tomohiko Isobe, Shin Takahashi, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 62 (1) 89 - 98 0025-326X 2011/01 [Peer-reviewed]
     Scientific journal 
    A total of 33 surficial sediments from riverine and coastal waters from Surabaya, Indonesia were analyzed for PCBs and BFRs. Concentrations of PCBs (62 congeners), PBDEs (14 congeners) and HBCDs (3 isomers) varied from <DL-420, <DL-35 and <DL-5.4 ng g(-1) dw, respectively. Higher concentrations of these compounds were found in riverine than coastal sediments. Their levels and distribution were influenced by proximity to the point sources and TOC. The predominant congeners were CB-153, -28, -138, -149, -180, -33 and BDE-209, -207, -206, -197, -196, -183, -99, -47 for PCBs and PBDEs, respectively, and gamma-isomer for HBCDs. Debromination of BDE-209 might be taking place producing lower toxic congeners in sediment. Levels of PCBs in riverine sediments were comparable with some polluted areas worldwide, but PBDEs and HBCDs were lower. Hazard assessment of PCBs indicated possible toxic potential, particularly in areas close to point sources. (C) 2010 Elsevier Ltd. All rights reserved.
  • Agus Sudaryanto, Tomohiko Isobe, Shin Takahashi, Shinsuke Tanabe
    CHEMOSPHERE 82 (5) 679 - 686 0045-6535 2011/01 [Peer-reviewed]
     Scientific journal 
    Organochlorine compounds (OCs) in sediments collected from various locations in Lower Mekong River Basin (MRB) in Laos and Thailand were examined to elucidate their occurrence, distribution and potential ecological risk. Concentration of PCBs and DDTs were higher than other OCs, ranging from 0.18 to 310 mu g kg(-1) dry wt. and from 0.027 to 52 mu g kg(-1) dry wt., respectively, whereas CHLs, HCHs and HCB were 1-3 orders of magnitude lower. Geographical distribution indicates that levels of PCBs, DDTs and CHLs in the Vientiane canal were significantly higher than those in mainstream of Mekong River, Phong River and its surrounding areas, indicating significant sources of these compounds in urbanized areas. Comparison with other parts of MRB indicates that PCBs were higher in Laos, whereas DDTs were more prevalent in Mekong Delta, indicating location specific contaminations of these compounds in MRB. The ratios of DDTs composition indicate possible difference in the historical input of DDT among locations in and around Mekong River. Hazard assessment of PCBs and DDTs indicate possible toxic potential particularly in areas close to point sources such as intensive human activities and agricultural areas which highlight the need for further study. (C) 2010 Elsevier Ltd. All rights reserved.
  • Yasumi Anan, Kazuya Ishiwata, Noriyuki Suzuki, Shinsuke Tanabe, Yasumitsu Ogra
    JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY 26 (1) 80 - 85 0267-9477 2011 [Peer-reviewed]
     Scientific journal 
    It is known that marine mammals and seabirds co-accumulate selenium (Se) and mercury (Hg) in their organs in the insoluble form called mercury selenide. In this study, we found that two sea turtles, hawksbill turtle (Eretmochelys imbricata) and green turtle (Chelonia mydas), accumulated Se but not Hg in their livers. Se speciation by HPLC-ICP-MS demonstrated that the livers contained low molecular weight selenometabolites in addition to selenoproteins. Two of the selenometabolites existed in relatively small amounts and were identified as selenosugar (1 beta-methylseleno-N-acetyl-D-galactosamine) and trimethylselenonium (TMSe) based on their chromatographic behavior. This suggests that selenosugar and TMSe are Se metabolites common to marine and terrestrial animals. The chromatographic behavior of the major hepatic selenometabolite in sea turtles was unique and did not match that of any authentic Se standards. Further analysis using HPLC-ESI-MS-MS revealed it to be selenoneine (2-selenyl-N,N,N-trimethyl-L-histidine), a metabolite that was recently identified in the blood of bluefin tuna. The results suggest that sea turtles possess specific mechanisms for Se metabolism to result in the sole accumulation of Se.
  • Nguyen M. Tue, Go Suzuki, Shin Takahashi, Tomohiko Isobe, Pham T. K. Trang, Pham H. Viet, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 44 (23) 9195 - 9200 0013-936X 2010/12 [Peer-reviewed]
     Scientific journal 
    Few studies have investigated the human exposure to the ensemble of dioxin-related compounds (DRCs) released from uncontrolled e-waste recycling, especially from a toxic effect standpoint This study evaluated the TCDD toxic equivalents (TEQs) in persistent extracts of settled house dust from two Vietnamese e-waste recycling sites (EWRSs) using the Dioxin-Responsive Chemically Activated LUciferase gene eXpression assay (DR-CALUX), combined with chemical analysis of PCDD/Fs, DL-PCBs, PBDD/Fs, and monobromo PCDD/Fs to determine their TEQ contribution. The CALUX-TEQ levels in house dust ranged from 370 to 1000 pg g(-1) in the EWRSs, approximately 3.5-fold higher than in the urban control site. In EWRS house dust, the concentrations of the unregulated PBDFs were 7.7-63 ng g(-1), an order of magnitude higher than those of regulated DRCs (PCDD/Fs and DL-PCBs), and PBDFs were also principal CALUX-TEQ contributors (4.2-22%), comparable to PCDD/Fs (8.1-29%). The CALUX-TEQ contribution of DRCs varied, possibly depending on thermal processing activities (higher PCDD/F-TEQs) and PBDE content in the waste (higher PBDF-TEQs). However, the percentage of unknown dioxin-like activities was high in all dust samples, indicating large contribution from unidentified DRCs and/or synergy among contaminants. Estimates of TEQ intake from dust ingestion suggest that children in the EWRSs may be adversely affected by DRCs from dust.
  • Nguyen Minh Tue, Agus Sudaryanto, Tu Binh Minh, Bui Hong Nhat, Tomohiko Isobe, Shin Takahashi, Pham Hung Viet, Shinsuke Tanabe
    CHEMOSPHERE 81 (8) 1006 - 1011 0045-6535 2010/11 [Peer-reviewed]
     Scientific journal 
    The present study investigated the current contamination status and evaluated several kinetic-related features of organochlorine pesticides (OCPs) and PCBs in human breast milk collected from northern Vietnam. The variation in the levels of these contaminants was found to be strongly associated with total lactation time and dietary habits. OCPs exhibited the characteristics of steadily declining compounds: the overall levels of DDTs and HCHs in the population decreased with a half-time of only 5 years and it can be suggested that OCPs depurated relatively fast with breastfeeding (5% per month). PCBs were slower in both regards, with a temporal decrease half-time of 12 years and a suggested depuration rate via breastfeeding of 2.5% per month, indicating that the exposure level was still high relative to the human body burden. It was found that the PCB exposure levels of infant from breastfeeding exceeded the reference dose, and this situation may continue for the next two or three decades. Knowledge of these kinetic-related characteristics not only is useful for risk assessment and prediction of future trends of legacy contaminants but also may provide insight regarding similar kinetic processes of emerging persistent pollutants. (C) 2010 Elsevier Ltd. All rights reserved.
  • Go Suzuki, Masayuki Someya, Shin Takahashi, Shinsuke Tanabe, Shin-ichi Sakai, Hidetaka Takigami
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 44 (21) 8330 - 8336 0013-936X 2010/11 [Peer-reviewed]
     Scientific journal 
    In our previous study, we demonstrated that dioxin-like activity in sulfuric-acid-treated extracts of Japanese indoor dust was higher than the activity in contaminated sediments. In the current study, we used high-performance liquid chromatography (HPLC) fractionation in combination with the dioxin-responsive chemical-activated luciferase gene expression (DR-CALUX) assay and gas chromatography-high-resolution mass spectrometry (GC-HRMS) to quantitatively evaluate dioxin-like compounds in indoor dusts. Selected four sulfuric-acid-treated extracts of indoor dusts were fractionated into seven fractions by means of HPLC with a nitrophenylpropylsilica column, and the activity in the first fraction of each extract was much higher than the activities in the other fractions. Therefore, each of the first fractions was further fractionated into 90 fractions by HPLC with an octadecylsilica column, and all the fractions were analyzed by means of the DR-CALUX assay. On the basis of elution characteristics, the active compounds in the fractions showing high activity were determined to be polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), coplanar polychlorinated biphenyls (Co-PCBs), and polychlorinated naphthalenes (PCNs), or supposed to be polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs). These compounds in the 33 dusts extracts were quantified by means of GC-HRMS, and their median-based contributions of the theoretical CALUX-TEQs [2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-tetraCDD) equivalent] chemically calculated for PBDFs, PCDDs, PCDFs, non-ortho Co-PCBs, PCNs, and mono-ortho Co-PCBs to the experimental values (38-1400 pg/g, median 160 pg/g) were 17%, 14%, 8.8%, 0.98%, 0.10%, and 0.019%, respectively. Our results indicate that PBDFs, which are not internationally regulated dioxins, were important contributors to dioxin-like activity in Japanese dust and that further analysis of PBDFs in indoor dust is required so that the risk of exposure to these compounds via dust can be assessed.
  • Kei Nakayama, Itsuki C. Handoh, Shin-Ichi Kitamura, Eun-Young Kim, Hisato Iwata, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 408 (23) 5824 - 5827 0048-9697 2010/11 [Peer-reviewed]
     Scientific journal 
    Here we propose a novel microarray data analysis method applicable to evaluation of the chemical effects on wild animals First, we analyzed correlations between log-transformed hepatic 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent (TEQ) levels and probe signals detected in wild cormorant liver to screen contaminant-responsive genes Second, principal component analysis (PCA) was conducted using the screened probes Third, these probes were divided into two groups based on our PCA result Finally, we calculated Euclidian distance of signals, which is equivalent to variance of gene expressions, in each probe set, and analyzed the relationship between log-transformed hepatic TEQ levels and Euclidian distances A probe set whereby the calculated Euclidian distance was positively correlated with TEQ levels, could indicate genes that were directly affected by dioxins or other persistent organic pollutants (POPs), hence they can be used as biomarkers By contrast, there were a number of probes whereby the Euclidian distance was negatively correlated with TEQ levels In the latter probe group, the smaller Euclidian distances in highly contaminated individuals could point to changes in physiological activities of wild cormorants Therefore, our microarray data analysis method will provide new insights into POPs-responsive genes in field-collected samples for toxicogenomics studies (C) 2010 Elsevier BV All rights reserved
  • Tatsuya Kunisue, Shinsuke Tanabe, Tomohiko Isobe, Kenneth M. Aldous, Kurunthachalam Kannan
    JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 58 (17) 9838 - 9846 0021-8561 2010/09 [Peer-reviewed]
     Scientific journal 
    Intake of a diet rich in phytoestrogens has been associated with a decreased risk for hormone-dependent cancers in humans. Biomonitoring of phytoestrogens in human urine has been used to assess the intake of phytoestrogens. Although studies have reported phytoestrogen levels in urine specimens from the United States and Japan, little is known of human intake of phytoestrogens in other Asian countries. In this study we determined the concentrations of seven phytoestrogens, namely, enterolactone, enterodiol, daidzein, equol, O-desmethylangolensin (O-DMA), genistein, and coumestrol, in 199 human urine samples from three Asian countries, Vietnam (Hanoi and Ho Chi Minh), Cambodia (Phnom Penh), and India (Chennai and Kolkata), using a simple, sensitive, and reliable liquid chromatography (LC)-tandem mass spectrometry (MS/MS) method. The residue levels of phytoestrogens in urine samples from the three Asian countries were compared with the concentrations in 26 urine samples from Japan (Ehime) and 16 urine samples from the United States (Albany), analyzed in this study. Among the phytoestrogens analyzed, isoflavones such as daidzein and genistein were predominant in urine samples from Vietnam; samples from Cambodia and India contained higher concentrations of enterolactone than isoflavones. Urinary concentrations of isoflavones in samples from Hanoi, Vietnam, were notably higher than the concentrations in samples from Cambodia, India, and the United States and similar to the concentrations in samples from Japan. The lowest concentrations of daidzein and the highest concentrations of enterolactone were found in urine samples from India. Concentrations of equol and O-DMA, which are microbial transformation products of daidzein (produced by gut microflora), were notably high in urine samples from Hanoi, Vietnam. The ratios of the concentration of equol or O-DMA to that of daidzein were significantly higher in samples from Hanoi than from Japan, indicating high biotransformation efficiency of daidzein by the population in Hanoi. High concentrations of equol, in addition to isoflavones, in urine have been linked to reduced breast cancer risk in previous studies, and, thus, the Vietnamese population may have potential protective effect against breast cancer. This study suggests that the dietary intake and profiles of phytoestrogens vary considerably, even among Asian countries.
  • Kwadwo Ansong Asante, Tetsuro Agusa, Reiji Kubota, Hiroko Mochizuki, Karri Ramu, Shuhei Nishida, Suguru Ohta, Hsin-ming Yeh, Annamalai Subramanian, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 60 (9) 1560 - 1570 0025-326X 2010/09 [Peer-reviewed]
     Scientific journal 
    Trace elements (TEs) and stable isotope ratios (delta N-15 and delta C-13) were analyzed in fish from deep-water of the Sulu Sea, the Celebes Sea and the Philippine Sea. Concentrations of V and Pb in pelagic fish from the Sulu Sea were higher than those from the Celebes Sea, whereas the opposite trend was observed for delta C-13. High concentrations of Zn, Cu and Ag were found in non-migrant fish in deep-water, while Rb level was high in fish which migrate up to the epipelagic zone, probably resulting from differences in background levels of these TEs in each water environment or function of adaptation to deep-water by migrant and non-migrant species. Arsenic level in the Sulu Sea fish was positively correlated with delta N-15, indicating bio-magnification of arsenic. To our knowledge, this is the first study on relationship between diel vertical migration and TE accumulation in deep-water fish. (C) 2010 Elsevier Ltd. All rights reserved.
  • Yi Wan, Paul D. Jones, Steve Wiseman, Hong Chang, Dave Chorney, Kurunthachalam Kannan, Kun Zhang, Jian-Ying Hu, Jong Seong Khim, Shinsuke Tanabe, Michael H. W. Lam, John P. Giesy
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 44 (16) 6068 - 6073 0013-936X 2010/08 [Peer-reviewed]
     Scientific journal 
    An extraction, separation, and purification method was developed for the identification and quantification of total bromine (TBr), extractable organobromine (EOBr), and five classes of identified EOBrs Instrumental neutron activation analysis (INAA) was utilized to quantify EOBr and TBr The method was then applied to liver samples of tuna, albatross, and polar bear collected from remote marine locations Polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), bromophenols (BRPs), hydroxylated (OH-) and methoxylated (MeO-) PBDEs were analyzed as identified EOBr The majority of the bromine in these marine organisms was nonextractable or inorganic, with EOBr accounting for 10-28% of the TBr. Of the identified EOBr, in tuna and albatross, naturally occurring compounds, including MeO-PBOEs, OH-PBDEs, and BPRs, were prevalent However, the identifiable EOBr in polar bears consisted primarily of synthetic compounds, including PBDEs and PBBs Overall, 0,08-011% and 0.008-0012% of EOBr and TBr, respectively, were identified The proportion of EOBr that was identified in marine organisms was relatively small compared to the proportions for organofluorine and organochlorine compounds This could be related to the great diversity of naturally occurring organobromine compounds in the environment. Naturally occurring brominated fatty acids were estimated to be the predominant compounds in the EOBr fraction.
  • Tomoko Koito, Kaoru Kubokawa, Shinsuke Tanabe, Nobuyuki Miyazaki
    FISHERIES SCIENCE 76 (4) 571 - 576 0919-9268 2010/07 [Peer-reviewed]
     Scientific journal 
    The short wavelength sensitive (SWS) opsin gene is expected to contain informative sites for understanding the speciation of the family Delphinidae, because it is not functional in cetaceans. We determined partial SWS gene sequences from 15 delphinid species of 12 genera and from harbor porpoise for comparison. We found a 39-bp insertion that was shared by six species (the insertion group: Delphinus delphis, Delphinus capensis, Stenella longirostris, Stenella coeruleoalba, Lagenodelphis hosei, and Sousa chinensis) and common base substitutions shared by eight species (Stenella frontalis, Tursiops truncatus, and six species of the insertion group). As these insertions and substitutions are not found in the other seven delphinids or in the cloven-hoofed mammals (which are close to cetaceans), it is suggested that these eight species are more closely related to each other than to the other species. This hypothesis is supported by phylogenetic analyses. The eight species with the substitutions formed a clade containing two sister clades, one consisting of the insertion group and the other consisting of the two other species, in both neighbor-joining and Bayes analyses. Phylogenetic analyses also showed that Lissodelphis borealis and Lagenorhynchus obliquidens are closely related and that their common ancestor diverged from the others at an early stage of delphinid evolution.
  • Michio X. Watanabe, Tatsuya Kunisue, Lin Tao, Kurunthachalam Kannan, Annamalai Subramanian, Shinsuke Tanabe, Hisato Iwata
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 29 (7) 1551 - 1560 0730-7268 2010/07 [Peer-reviewed]
     Scientific journal 
    Dioxins and related compounds (DRCs) and perfluorinated compounds were measured in the livers of pigs (Sus scrofa) collected from an open waste dumping site in South India. Hepatic concentrations of DRCs and perfluorooctanesulfonate (PFOS; up to 200 ng/g wet wt) were significantly higher in male and female pigs, respectively, collected from the dumping site than in those from a reference site. Results suggest that dumping sites are a source of DRCs and PFOS. Hepatic concentrations of DRCs in piglets were higher than in mothers, especially for the congeners with molecular weights in the range of 360 to 400, implying congener-specific maternal transfer of DRCs in swine. Concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans and some non-ortho dioxin-like polychlorinated biphenyls (PCBs) in the liver of pigs were higher than those in the adipose fat and muscle of the same specimens. In addition, the liver-to-adipose concentration ratios for each congener had a significant positive correlation with the levels of hepatic cytochrome P450 (CYP)1A-like protein, suggesting congener-specific and CYP1A-dependent hepatic sequestration of DRCs in the swine. Total hepatic 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs; 8.9-350 pg/g fat wt) had a significant positive correlation with CYP1A-like protein expression (r= 0.56, p = 0.012), suggesting the induction of CYP1A by DRCs. However, the total TEQs had a significant negative correlation with CYP4A-like protein (r= -0.49, p= 0.029), suggesting repression of peroxisome proliferator-activated receptor-alpha (PPAR alpha)-mediated signaling pathway by DRCs. Decreases in plasma total thyroxine (T(4)), free T(4), and immunoglobulin (Ig) G were also found in pigs from the dumping site compared with those from the reference site. This study provides insight into the toxicological impacts of DRCs and perfluorinated compounds in wild animals from open waste dumping sites. Environ. Toxicol. Chem. 2010;29:1551-1560. (C) 2010 SETAC
  • Tatsuya Kunisue, Qian Wu, Shinsuke Tanabe, Kenneth M. Aldous, Kurunthachalam Kannan
    ANALYTICAL METHODS 2 (6) 707 - 713 1759-9660 2010/06 [Peer-reviewed]
     Scientific journal 
    Benzophenone (BP)-type UV (ultraviolet) filters, especially 2-hydroxy-4-methoxybenzophenone (2OH-4MeO-BP), are widely used in the U S, to protect the skin and hair from UV irradiation Despite human exposures to UV filters through the dermal application of products containing sunscreen aunts, few studies have examined the occurrence of UV filters in humans. Thus far, few sensitive methods are available for the determination of 2OH-4MeO-BP in human urine Furthermore, methods for the determination of other BP derivatives, including 2,4-dihydroxybenzophenone (2,4OH-BP), which is formed from 2OH-4MeO-BP via metabolic activities of the cytochrome P450 enzymes. have not been available In this study, we have developed a method for the analysis of five BP derivatives 2OH-4MeO-BP, 2,4OH-BP, 2,2'-dihydroxy-4-methoxybenzophenone (2,2'OH-4MeO-BP). 2,2'.4,4'-tetrahydroxybenzophenone (2,2'.4,4'OH-BP), and 4-hydroxybenzophenone (4OH-BP) in human urine, using liquid-liquid extraction and liquid chromatograph (LC)-tandem mass spectrometer (MS/MS) analysis The instrumental calibration range for each of the BP derivatives ranged from 0 05 to 100 ng ml(-1), and showed excellent linearity (r > 0 99) The respective limits of detection (LODs) and limits of quantification (LOQs) were determined to be 0 082 and 0 28 ng ml(-1) for both 2,4OH-BP and 4OH-BP; 0.13 and 0 44 ng ml(-1) for 2,2'OH-4MeO-BP, and 0 28 and 0 90 ng ml(-1) for both 2OH-4MeO-BP and 2,2',4,4'OH-BP Recoveries of BP derivatives through the entire analytical procedure were between 85.2 and 99 6%. The coefficients of variation (CVs) of five replicate analyses within I day, and across 5 days, were respectively 1.4 and 3 7% for 2.4OH-BP, 1 7 and 3 0% for 2OH-4MeO-BP, and 2 8 and 4 5% for 4OH-BP When BP derivatives were determined in urine samples from 23 U S (Albany, New York) and 22 Japanese (Matsuyama, Ehime) volunteers, higher concentrations of 2,4OH-BP, 2OH-4MeO-BP, and 4OH-BP were found in samples collected from females in the Albany cohort, probably reflecting great usage by U S. females. The urine sample from a known sunscreen user contained very high concentrations of 2,4OH-BP and 2OH-4MeO-BP. 2,2',4,4'OH-BP and 2,2'OH-4MeO-BP were not detected in any of the urine samples analyzed Our results indicate considerable exposure to highly estrogenic 2,4OH-BP and 2OH-4MeO-BP by females in the U S and suggest the need for further studies on potential health effects.
  • ベトナム人におけるAS3MT遺伝子多型とヒ素代謝能の関係
    阿草哲郎, 藤原純子, 竹下治男, 田辺信介, 岩田久人, 國頭 恭
    DNA多型 18 (1) 242 - 245 2010/05 [Peer-reviewed]
  • Kei Nomiyama, Satoko Murata, Tatsuya Kunisue, Tadasu K. Yamada, Hazuki Mizukawa, Shin Takahashi, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 44 (10) 3732 - 3738 0013-936X 2010/05 [Peer-reviewed]
     Scientific journal 
    In this study, we determined the residue levels and patterns of polychlorinated biphenyls (PCBs) and hydroxylated PCBs (OH-PCBs) in the blood from eight species of toothed whales and three species of baleen whales stranded along the Japanese coast during 1999-2007. Penta- through hepta-chlorinated PCB congeners were the dominant homologue groups in all cetaceans. In contrast, specific differences in the distribution of dominant OH-PCB isomers and homologues were found among the cetacean species. In five species of toothed whales (melon-headed whale, Stejneger's beaked whale, Pacific white-sided dolphin, Blainville's beaked whale, and killer whale), the predominant homologues were OH-penta-PCBs followed by OH-tetra-PCBs and OH-tri-PCBs. The predominant homologues of finless porpoise and beluga whale were OH-penta-PCBs followed by OH-hexa-PCBs and OH-tri-PCBs. The predominant OH-PCB isomers were para-OH-PCBs such as 4'OH-CB26, 4'OH-CB25/4'OH-CB26/4OH-CB31, 4OH-CB70, 4'OH-CB72, 4'OH-CB97, 4'OH-CB101/4'OH-CB120, and 4OH-CB107/4'OH-CB108 in toothed whales. In three baleen whales (common minke whale, Bryde's whale, and humpback whale) and in sperm whale (which is a toothed whale), OH-octa-PCB (4OH-CB202) was the predominant homologue group accounting for 40-80% of the total OH-PCB concentrations. The differences in concentrations and profiles of OH-PCBs may suggest species-specific diets, metabolic capability, and the transthyretin (TTR) binding specificity. These results reveal that the accumulation profiles of OH-PCBs in cetacean blood are entirely different from the profiles found in pinnipeds, polar bear, and humans.
  • Akira Kubota, Mafumi Watanabe, Tatsuya Kunisue, Eun-Young Kim, Shinsuke Tanabe, Hisato Iwata
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 44 (9) 3559 - 3565 0013-936X 2010/05 [Peer-reviewed]
     Scientific journal 
    The present study assesses effects of dioxins and related compounds (DRCs) including polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls (DL-PCBs) on cytochrome P450 1A (CYP1A) expression level in liver of black-footed albatrosses (Phoebastria nigripes) collected from the North Pacific, Total 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-T4CDD) toxic equivalents (TEQs) derived from toxic equivalency factor for birds proposed by World Health Organization were in the range of 2100 to 10 000 pg/g lipid wt (120-570 pg/g wet wt). Simultaneously, microsomal alkoxyresorufin O-dealkylase (AROD) activities, including methoxy-, ethoxy-, pentoxy-, and benzyloxy-resorufin O-dealkylase activities were also measured in the same specimens. Total TEQs and TEQ (on wet wt basis) from some individual DRC congeners had significant positive correlations with AROD activities, suggesting induction of CYP1A by DRCs. Congeners like 2,3,7,8-T4CDD and most of the DL-PCBs that showed no significant positive correlations between the concentrations and AROD activities, exhibited significant negative correlations between AROD activities and the concentration ratio of the congener to a recalcitrant CB169, suggesting preferential metabolism of these congeners by induced CYP1A. As far as we know, this is the first direct evidence revealing that hepatic CYP1A level is elevated with the accumulation of DRCs in the wild black-footed albatross population. The present study gives more robust estimate of impacts of DRCs on CYP1A induction in this rare pelagic species than indexes like hazard quotient and TEQ-threshold comparison that have been so far carried out.
  • Kurunthachalam Kannan, Shin Takahashi, Naohiro Fujiwara, Hazuki Mizukawa, Shinsuke Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 58 (4) 901 - 907 0090-4341 2010/05 [Peer-reviewed]
     Scientific journal 
    Organotin compounds (OTs) have been used in a wide variety of consumer products. Despite this, very few studies have reported the occurrence of OTs in house dust or exposure of humans to OTs through the ingestion of house dust. In the present study, concentrations of monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), monooctyltin (MOT), dioctyltin (DOT), trioctyltin (TOT), diphenyltin (DPT), and triphenyltin (TPT) were measured in dust collected from 24 houses in Albany, New York, USA. In addition, a few household products, such as wallpaper, floor tile, vinyl window blinds, and handbags were analyzed for the presence of OTs. Organotins were found in all of the house dust samples analyzed, and total OT concentrations varied from 390 to 28,000 ng/g (mean +/- A SD: 6700 +/- A 6200; median: 5000). Relative abundances of OTs in house dust were in the order MBT > MOT > DBT > DOT > TBT. TOT, DPT, and TPT were not found in any of the samples at concentrations above their corresponding detection limits. MBT accounted for, on average, 51% of the total OT concentrations. Mean concentrations of total OTs found in house dust samples from our study were two to five times higher than concentrations that have been reported for dust samples from several European countries. Calculations indicate that dust ingestion by children account for, on average, 15-18% of the tolerable daily intake proposed by the World Health Organization (WHO). The estimated rates of OT intake by children via dust ingestion were, on average, eightfold higher than the intake rates calculated for adults. Household products, such as wallpaper, contained total OT concentrations as high as 780,000 ng/g.
  • Karri Ramu, Tomohiko Isobe, Shin Takahashi, Eun-Young Kim, Byung-Yoon Min, Sung-Ug We, Shinsuke Tanabe
    CHEMOSPHERE 79 (7) 713 - 719 0045-6535 2010/04 [Peer-reviewed]
     Scientific journal 
    Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) were determined in surface sediments collected from 24 coastal locations in Korea. The concentrations of Sigma(PBDEs) (defined as the sum of all targeted PBDE congeners except for BDE-209) and BDE-209 ranged from 0.05 to 32 ng g(-1) dry wt. and from 0.40 to 98 ng g(-1) dry wt., respectively. The PBDE congener compositions were dominated by BDE-209, which is in accordance with the consumption of decaBDE mixture in Korea. HBCD concentrations ranged from 0.39 to 59 ng g(-1) dry wt. Concentrations of PBDEs and HBCDs were found to be higher near locations with industrial complexes and harbors, associating these compounds to urbanization and industrialization. Significant positive correlations between PBDE and HBCD concentrations and organic carbon content in sediments imply the role played by organic matter in the contaminant transport and trapping in the aquatic environment. (C) 2010 Elsevier Ltd. All rights reserved.
  • Nguyen Minh Tue, Agus Sudaryanto, Tu Binh Minh, Tomohiko Isobe, Shin Takahashi, Pham Hung Viet, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 408 (9) 2155 - 2162 0048-9697 2010/04 [Peer-reviewed]
     Scientific journal 
    This study investigated the contamination status of PCBs, PBDEs and HBCDs in human and possible exposure pathways in three Vietnamese e-waste recycling sites: Trang Minh (suburb of Hai Phong city), Dung Mai and Bui Dau (Hung Yen province), and one reference site (capital city Hanoi) by analysing human breast milk samples and examining the relationships between contaminant levels and lifestyle factors. Levels of PBDEs, but not PCBs and HBCDs, were significantly higher in Trang Minh and Bui Dau than in the reference site. The recyclers from Bui Dau had the highest levels of PBDEs (20-250 ng g(-1) lipid wt.), higher than in the reference group by two orders of magnitude and more abundant than PCBs (28-59 ng g(-1) lipid wt.), and were also the only group with significant exposure to HBCDs (1.4-7.6 ng g(-1) lipid wt.). A specific accumulation, unrelated to diet, of low-chlorinated PCBs and high-brominated PBDEs was observed in e-waste recyclers, suggesting extensive exposure to these compounds during e-waste recycling activities, possibly through inhalation and ingestion of dust. The estimated infant intake dose of PBDEs from breast milk of some mothers occupationally involved in e-waste recycling were close to or higher than the reference doses issued by the U.S. EPA. (C) 2010 Elsevier B.V. All rights reserved.
  • D. Ueno, T. Isobe, K. Ramu, S. Tanabe, M. Alaee, C. Marvin, K. Inoue, T. Someya, T. Miyajima, H. Kodama, H. Nakata
    CHEMOSPHERE 78 (10) 1213 - 1219 0045-6535 2010/03 [Peer-reviewed]
     Scientific journal 
    In order to elucidate the spatial distribution of brominated flame retardants (BFRs) in the Japanese coastal environment, hexabromocycloclodecanes (HBCDs), polybrominated diphenyl ethers (PBDEs) and organochlorines (OCs: PCBs, DDTs, CHLs HCHs, HCB) were determined in bivalves (oysters and mussels) collected from Japanese coastal waters. HBCDs and PBDEs were detected in all samples analyzed. Concentration ranges of HBCDs were 12-5200 ng g(-1) lipid wt., followed by PCBs (203100 ng g(-1)) > PBDEs (3.1-86 ng g(-1) lipid wt.). The highest concentration of HBCDs was found in the Osaka region. This result indicates that HBCDs are ubiquitous and predominant compounds in bivalves from the Japanese coastal waters. Since no species differences between oysters and mussels were observed for the bioaccumulation properties of HBCDs and PBDEs, oysters could be utilized for BFR contamination monitoring worldwide as an alternative to mussels. Global comparisons between oysters and mussels showed that HBCD concentrations in Japan are among the highest levels reported from Asia and Europe. Estimated dietary exposures of HBCDs and PBDEs through seafood were 0.45-34 ng kg body weight(-1) d(-1), and 0.054-6.8 ng kg body weight(-1) d(-1), respectively. These exposure levels were more than 1000 times lower than the lowest observable effects or no observable adverse effects levels for HBCDs and PBDEs, respectively. (C) 2009 Elsevier Ltd. All rights reserved.
  • Shin Takahashi, Tomoko Oshihoi, Karri Ramu, Tomohiko Isobe, Koji Ohmori, Tsunemi Kubodera, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 60 (2) 187 - 196 0025-326X 2010/02 [Peer-reviewed]
     Scientific journal 
    Twelve species of deep-sea fishes collected in 2005 from the western North Pacific, off-Tohoku, Japan were analyzed for organohalogen compounds. Among the compounds analyzed, concentrations of DDTs and PCBs (up to 23,000 and 12,400 ng/g lipid wt, respectively) were the highest. The present study is the foremost to report the occurrence of brominated flame retardants such as PBDEs and HBCDs in deep-sea organisms from the North Pacific region. Significant positive correlations found between delta N-15 (parts per thousand) and PCBs, DDTs and PBDEs suggest the high biomagnification potential of these contaminants in food web. The large variation in delta C-13 (parts per thousand) values observed between the species indicate multiple sources of carbon in the food web and specific accumulation of hydrophobic organohalogen compounds in benthic dwelling carnivore species like snubnosed eel. The results obtained in this study highlight the usefulness of deep-sea fishes as sentinel species to monitor the deep-sea environment. (C) 2009 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Hisato Iwata, Junko Fujihara, Takashi Kunito, Haruo Takeshita, Tu Binh Minh, Pham Thi Kim Trang, Pham Hung Viet, Shinsuke Tanabe
    TOXICOLOGY AND APPLIED PHARMACOLOGY 242 (3) 352 - 362 0041-008X 2010/02 [Peer-reviewed]
     Scientific journal 
    To elucidate the role of genetic factors in arsenic metabolism, we investigated associations of genetic polymorphisms in the members of glutathione S-transferase (GST) superfamily with the arsenic concentrations in hair and urine, and urinary arsenic profile in residents in the Red River Delta, Vietnam. Genotyping was conducted for CST omega 1 (GSTO1) A1a140Asp, Glu155del, Glu208Lys, Thr217Asn, and Ala236Val, GST omega 2 (GSTO2) Asn142Asp, CST pi 1 (GSTP1) Ile105Val, GST mu 1 (GSTM1) wild/null, and GST theta 1 (GSTT1) wild/null. There were no mutation alleles for GSTO1 Glu208Lys, Thr217Asn, and Ala236Val in this population. GSTO1 Glu 155del hetero type showed higher urinary concentration of As(V) than the wild homo type. Higher percentage of DMA(V) in urine of GSTM1 wild type was observed compared with that of the null type. Strong correlations between GSTP1 Ile105Val and arsenic exposure level and profile were observed in this study. Especially, heterozygote of GSTP1 Ile105Val had a higher metabolic capacity from inorganic arsenic to monomethyl arsenic, while the opposite trend was observed for ability of metabolism from As(V) to As(III). Furthermore, other factors including sex, age, body mass index, arsenic level in drinking water, and genotypes of As (+ 3 oxidation state) methyltransferase (AS3MT) were also significantly co-associated with arsenic level and profile in the Vietnamese. To our knowledge, this is the first study indicating the associations of genetic factors of CST superfamily with arsenic metabolism in a Vietnamese population. (C) 2009 Elsevier Inc. All rights reserved.
  • Masayuki Someya, Masako Ohtake, Tatsuya Kunisue, Annamalai Subramanian, Shin Takahashi, Paromita Chakraborty, Ramesh Ramachandran, Shinsuke Tanabe
    ENVIRONMENT INTERNATIONAL 36 (1) 27 - 35 0160-4120 2010/01 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organic Pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and organochlorine pesticides were measured in human breast milk collected from mothers residing near an open dumping site and a reference site in Kolkata, India during 2004-2005. POPs were detected in all the human milk samples analyzed, suggesting that residents of Kolkata are widely exposed to these contaminants. Concentrations of dioxin-like PCBs in the samples from the dumping site were significantly higher than in the reference site samples, whereas no such difference was found for PCDDs and PCDFs. In addition, significantly higher concentrations of total PCBs were also observed in the samples from the dumping site than the reference site. Interestingly, concentrations of total and dioxin-like PCBs in the breast milk of mothers from the dumping site significantly increased with the number of years of residence near the dumping site. These results indicate that significant pollution sources of PCBs are present in the dumping site of Kolkata and the residents living around are exposed to relatively higher levels of PCBs. When the residue levels of dioxins and related compounds in fish collected from ponds near the Kolkata dumping site and the reference site were measured, it was found that dioxin-like PCB and TEQ levels in fish from the dumping site were notably higher than those from the reference site. This result indicates that fish is a potential source of PCBs for residents living near the Kolkata dumping site. (C) 2009 Elsevier Ltd. All rights reserved.
  • Nakayama, K, Matsudaira, C, Tajima, Y, Yamada, T. K, Yoshioka, M, Isobe, T, Takahashi, S, Tanabe, S
    Science of the Total Environment 407 (24) 6173 - 6178 2009/12 [Peer-reviewed]
  • Yi Wan, Steve Wiseman, Hong Chang, Xiaowei Zhang, Paul D. Jones, Markus Hecker, Kurunthachalam Kannan, Shinsuke Tanabe, Jianying Hu, Michael H. W. Lam, John P. Giesy
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 43 (19) 7536 - 7542 0013-936X 2009/10 [Peer-reviewed]
     Scientific journal 
    Polybrominated diphenyl ethers (PBDEs) have been widely used as flame retardants. The structurally related hydroxylated PBDEs (OH-PBDEs) and methoxylated PBDEs (MeO-PBDEs) occur in precipitation, surface water, wildlife, and humans. The formation of OH-PBDEs in wildlife and humans is of considerable concern due to their greater toxicities relative to PBDEs and MeO-PBDEs. Research to date suggests that OH-PBDEs are formed by hydroxylation of PBDEs, and MeO-PBDEs are then formed by methylation of the OH-PBDEs. Here we show significant metabolic production of OH-PBDEs from MeO-PBDEs while hydroxylation of synthetic PBDEs to OH-PBDEs was negligible. Concentrations of PBDEs, OH-PBDEs, and MeO-PBDEs were analyzed in tuna, albatross, and polar bears collected from marine environments worldwide, and we found a closer relationship between OH-PBDEs and MeO-PBDEs than had been previously reported. Furthermore, for the first time the metabolic relationships between PBDEs, OH-PBDEs, and MeO-PBDEs were elucidated in vitro using rainbow trout chicken, and rat microsomes. We propose the production of OH-PBDEs from naturally occurring MeO-PBDEs as a previously unidentified mechanism that could be an important contributor for the occurrence of OH-PBDEs found in wildlife from remote areas. Our results suggest that risk assessment paradigms for PBDEs and their metabolites need reevaluation and that human exposure to MeO-PBDEs that occur naturally in marine organisms should be considered.
  • Ana Sousa, Filipe Laranjeiro, Shin Takahashi, Shinsuke Tanabe, Carlos M. Barroso
    CHEMOSPHERE 77 (4) 566 - 573 0045-6535 2009/10 [Peer-reviewed]
     Scientific journal 
    Imposex levels and organotin tissue concentrations were assessed in Nassarius reticulatus females collected between June and August 2008 at 23 sites along the Portuguese coast. Females with imposex were present at all sampling sites with highest levels inside main harbors. Imposex parameters across sampling stations varied between 6.3% and 100% for %I. 0.2-4.4 for VDSI, 0.1-7.8 mm for FPL 0.3-88.9% for RPLI and 0.0-1.1 for AOS. TBT levels varied between 3.5 and 380 ng Sn g(-1) dw, representing an average proportion of 50.4% of total butyltins (Sigma BTs = MBT + DBT + TBT). Sterile females were detected at two locations. Highly significant correlations between imposex and TBT levels were found. The efficacy of the EU legislation banning the use of TBT-based antifouling paints since 2003 (EC Regulation 782/2003) was evaluated by comparing the levels of imposex observed in 2008 with those reported for 2003. OTs tissue concentrations were also determined in preserved samples collected in 2003. There was a decrease in imposex and TBT tissue contamination between 2003 and 2008 indicating that a decline in TBT pollution has occurred in the Portuguese coast since the implementation of the legislation. Considering that the EC Regulation 782/2003 is an anticipation of the IMO AFS Convention, a global scale decrease in TBT pollution can be expected in the near future. Despite the rapid amelioration in the Portuguese coast, TBT pollution is still a problem as the Ecological Quality Objective (EcoQO) proposed by OSPAR Commission was not achieved in 91% of the surveyed sites. (C) 2009 Elsevier Ltd. All rights reserved.
  • Hiroki Sakai, Eun-Young Kim, Evgeny A. Petrov, Shinsuke Tanabe, Hisato Iwata
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 43 (16) 6391 - 6397 0013-936X 2009/08 [Peer-reviewed]
     Scientific journal 
    To characterize ligand-dependent transcriptional activation of constitutive active/androstane receptor (CAR) in aquatic mammals, transactivation potentials of the Baikal seal (Pusa sibirica) CAR (bsCAR) by environmental pollutants, including persistent organic pollutants (POPs) and brominated flame retardants (BFRs), were investigated using an in vitro reporter gene assay, and compared with those of the mouse CAR (mCAR). Measurement of luciferase reporter gene activities demonstrated that the seal CAR was activated by POPs, including a technical mixture of PCBs (Kanechlor-500), certain individual PCB congeners, DOT compounds, and trans-nonachlor. No or slight bsCAR-dependent activity was detected in experiments with PBDE congeners and HBCDs. The interspecies comparison of lowest observed effect concentration (LOEC) for CAR transactivation by each compound revealed that bsCAR responds more sensitively to PCBs than mCAR. In addition, bsCAR was weakly deactivated by PBDE99, whereas mCAR transcriptional activity decreased weakly by PBDE100, PBDE154, and PBDE187. Comparison of reporter gene activities by the congeners with the same IUPAC numbers among PCBs and PBDEs revealed that both bsCAR and mCAR were not activated by PBDE99 and PBDE153, but were activated by PCB99 and PCB153. The small ligand-binding pocket in CAR may contribute to difference in response between PCBs and PBDEs. Given that ethical rationale prevents dosing studies with such organohalogens in aquatic Mammals, Our in vitro assay system constructed with CAR cDNA from a species of interest provides a useful and realistic alternative approach in ecotoxicology.
  • Ana Sousa, Tokutaka Ikemoto, Shin Takahashi, Carlos Barroso, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 58 (8) 1130 - 1136 0025-326X 2009/08 [Peer-reviewed]
     Scientific journal 
    Despite the huge amount of literature available on butyltins (BuTs), few studies addressed the environmental levels of phenyltins (PhTs), octyltins (OcTs) and total tin (Sn-T) in environmental samples. In 2006 a mussel watch survey was developed for the Portuguese coast (total of 29 sampling sites) in order to describe the concentrations of BuTs, PhTs, OcTs and SnT in the whole tissues of Mytilus galloprovincialis (Lamarck, 1819). BuTs were detected in all analyzed samples accounting, in average, for 98.6% of total organotins (Sigma OTs = BuTs + PhTs + OcTs), and presented highest values in the vicinity of harbors. Tributyltin (TBT) was the dominant butyltin, representing, in average, 62% of Sigma BuTs (Sigma BuTs = TBT + DBT + MBT) suggesting that fresh inputs of TBT are still occurring in the Portuguese coast, particularly near harbors. The contribution of organotin compounds derived from antifouling paints to the total tin levels in M. galloprovincialis is discussed. (C) 2009 Elsevier Ltd. All rights reserved.
  • Tomohiko Isobe, Yoko Ochi, Karri Ramu, Takahito Yamamoto, Yuko Tajima, Tadasu K. Yamada, Masao Amano, Nobuyuki Miyazaki, Shin Takahashi, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 58 (3) 396 - 401 0025-326X 2009/08 [Peer-reviewed]
     Scientific journal 
    Organohalogen contaminants including PCBs, DDTs, CHLs, HCHs, HCB, PBDEs and HBCDs were determined in striped dolphins (Stenella coeruleoalba) found stranded at Gogo-shima (n = 6, 2003) and collected from Taiji (n = 15, 1978-1992) in Japan. All target compounds were significantly detected in all the specimens, indicating ubiquitous contamination of oceanic cetaceans in northwest Pacific Ocean. Examination of body distribution of organohalogens in the six specimens from Gogo-shima showed no significant difference in concentrations among the analyzed tissues, except for brain, which had lower levels possibly due to the existence of blood-brain barrier. For evaluating temporal trends, archived blubber samples of adult male stripped dolphins collected in 1978,1979,1986 and 1992 were analyzed. Concentrations of PCBs, DDTs and HCHs did not change significantly during 1978-2003. In contrast, remarkable increasing trends of PBDEs and HBCDs were observed, suggesting growing consumption in Japan and surrounding countries in recent years. (C) 2008 Elsevier Ltd. All rights reserved.
  • Govindan Malarvannan, Tatsuya Kunisue, Tomohiko Isobe, Agus Sudaryanto, Shin Takahashi, Maricar Prudente, Annamalai Subramanian, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 157 (6) 1924 - 1932 0269-7491 2009/06 [Peer-reviewed]
     Scientific journal 
    Human breast milk samples (n = 33) from primipara and multipara mothers from Payatas a waste dump site, and Malate a reference site in the Phillipines were collected in 2004 and analyzed for eight organohalogen compounds, viz., PCBs, DDTs, CHLs, HCHs, HCB, TCPMe, PBDEs and HBCDs. DDTs and PCBs were predominant in all the samples. Overall mean concentrations of PBDEs found in our study were higher (7.5 ng/g lipid wt.) than those reported for Japan and many other Asian countries. Primipara mothers had significantly higher levels of DDTs, CHLs and HCHs than multipara mothers, but not PBDEs and HBCDs. A few individuals accumulated CHLs close to or even higher than the tolerable daily intake guidelines proposed by Health Canada. (C) 2009 Elsevier Ltd. All rights reserved.
  • Sonoko Yamaguchi, Chiemi Miura, Kazuya Kikuchi, Fritzie T. Celino, Tetsuro Agusa, Shinsuke Tanabe, Takeshi Miura
    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 106 (26) 10859 - 10864 0027-8424 2009/06 [Peer-reviewed]
     Scientific journal 
    Zinc (Zn) plays important roles in various biological activities but there is little available information regarding its functions in spermatogenesis. In our current study, we further examined the role of Zn during spermatogenesis in the Japanese eel ( Anguilla japonica). Human CG (hCG) was injected into the animals to induce spermatogenesis, after which the concentration of Zn in the testis increased in tandem with the progression of spermatogenesis. Staining of testicular cells with a Zn-specific fluorescent probe revealed that Zn accumulates in germ cells, particularly in the mitochondria of spermatogonia and spermatozoa. Using an in vitro testicular organ culture system for the Japanese eel, production of a Zn deficiency by chelation with N,N,N',N'-tetrakis (2-pyridylemethyl) ethylenediamine ( TPEN) caused apoptosis of the germ cells. However, this cell death was rescued by the addition of Zn to the cultures. Furthermore, an induced deficiency of Zn by TPEN chelation was found to inhibit the germ cell proliferation induced by 11-ketotestosterone (KT), a fish specific androgen, 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (DHP), the initiator of meiosis in fish, and estradiol-17 beta (E2), an inducer of spermatogonial stem-cell renewal. We also investigated the effects of Zn deficiency on sperm motility and observed that TPEN treatment of eel sperm suppressed the rate and duration of their motility but that co-treatment with Zn blocked the effects of TPEN. Our present results thus suggest that Zn is an essential trace element for the maintenance of germ cells, the progression spermatogenesis, and the regulation of sperm motility.
  • Nguyen Ngoc Ha, Tetsuro Agusa, Karri Ramu, Nguyen Phuc Cam Tu, Satoko Murata, Keshav A. Bulbule, Peethmbaram Parthasaraty, Shin Takahashi, Annamalai Subramanian, Shinsuke Tanabe
    CHEMOSPHERE 76 (1) 9 - 15 0045-6535 2009/06 [Peer-reviewed]
     Scientific journal 
    The recycling and disposal of electronic waste (e-waste) in developing countries is causing an increasing concern due to its effects on the environment and associated human health risks. To understand the contamination status, we measured trace elements (TEs) in soil, air dust, and human hair collected from e-waste recycling sites (a recycling facility and backyard recycling units) and the reference sites in Bangalore and Chennai in India. Concentrations of Cu, Zn, Ag, Cd, In, Sn, Sb, Hg, Pb, and Bi were higher in soil from e-waste recycling sites compared to reference sites. For Cu, Sb, Hg, and Pb in some soils from e-waste sites, the levels exceeded screening values proposed by US Environmental Protection Agency (EPA). Concentrations of Cr, Mn, Co, Cu, In, Sn, Sb, Tl, Pb and Bi in air from the e-waste recycling facility were relatively higher than the levels in Chennai city. High levels of Cu, Mo, Ag, Cd, In, Sb, Tl, and Pb were observed in hair of male workers from e-waste recycling sites. Our results suggest that e-waste recycling and its disposal may lead to the environmental and human contamination by some TEs. To our knowledge, this is the first study on TE contamination at e-waste recycling sites in Bangalore, India. (C) 2009 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Hisato Iwata, Junko Fujihara, Takashi Kunito, Haruo Takeshita, Tu Binh Minh, Pham Thi Kim Trang, Pham Hung Viet, Shinsuke Tanabe
    TOXICOLOGY AND APPLIED PHARMACOLOGY 236 (2) 131 - 141 0041-008X 2009/04 [Peer-reviewed]
     Scientific journal 
    To elucidate the role of genetic factors in arsenic (As) metabolism, we studied associations of single nucleotide polymorph isms (SNPs) in As (+3 oxidation state) methyltransferase (AS3MT) with the As concentrations in hair and urine, and urinary As profile in residents in the Red River Delta, Vietnam. Concentrations of total As in groundwater were 0.7-502 mu g/l. Total As levels in groundwater drastically decreased by using sand filter, indicating that the filter could be effective to remove As from raw groundwater. Concentrations of inorganic As (IAs) in urine and total As in hair of males were higher than those of females. A significant positive correlation between monomethylarsonic acid (MMA)/IAs and age in females indicates that older females have higher methylation capacity from IAs to MMA. Body mass index negatively correlated with urinary As concentrations in males. Homozygote for SNPs 4602AA, 35991GG, and 37853GG, which showed strong linkage disequilibrium (LD), had higher percentage (%) of dimethylarsinic acid (DMA) in urine. SNPs; 4740 and 12590 had strong LD and associated with urinary %DMA. Although SNPs 6144, 12390, 14215, and 35587 comprised LD cluster, homozygotes in SNPs 12390GG and 35587CC had lower DMA/MMA in urine, suggesting low methylation capacity from MMA to DMA in homo types for these SNPs. SNPs 5913 and 8973 correlated with %MMA and %DMA, respectively. Heterozygote for SNP 14458TC had higher MMA/IAs in urine than TT homozygote, indicating that the heterozygote may have stronger methylation ability of IAs. To our knowledge, this is the first study on the association of genetic factors with As metabolism in Vietnamese. (C) 2009 Elsevier Inc. All rights reserved.
  • Hidenori Terauchi, Shin Takahashi, Paul K. S. Lam, Byung-Yoon Min, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 157 (3) 724 - 730 0269-7491 2009/03 [Peer-reviewed]
     Scientific journal 
    In this study we investigated occurrences and distribution patterns of dioxin-related compounds (DRCs) such as polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/Fs), polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), monobromo-polychlorinated dibenzo-p-dioxins/dibenzofurans (MoBPCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in marine surface sediments collected from the coastal waters of Hong Kong and Korea. In most sampling sites, concentrations of PCDDs were the highest, followed by DL-PCBs, PCDFs, PBDFs, PBDDs, MoBPCDDs and MoBPCDFs in this order. Levels of PBDD/Fs were generally 1-2 orders of magnitude lower than chlorinated analogues. Levels of PCDDs are higher than PCDFs in Hong Kong while levels of PBDFs are higher than PBDDs in Korea (p < 0.05). Report of PBDD/Fs and MoBPCDD/Fs in sediments from East Asian countries is novel and original. Environmental levels of PBDD/Fs are supposed to start increasing in accordance with rising production, use and disposal of brominated flame retardants (BFRs) and recycling processes of e-waste in Asian developing countries. (C) 2008 Elsevier Ltd. All rights reserved.
  • Daisuke Imaeda, Tatsuya Kunisue, Yoko Ochi, Hisato Iwata, Oyuna Tsydenova, Shin Takahashi, Masao Amano, Evgeny A. Petrov, Valeriy B. Batoev, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 157 (3) 737 - 747 0269-7491 2009/03 [Peer-reviewed]
     Scientific journal 
    This study investigated the accumulation features and temporal trends of PCDD/Fs, dioxin-like PCBs (DL-PCBs) and non-dioxin-like PCBs (NDL-PCBs) in the blubber of Baikal seals collected in 1992 and 2005. DL-PCBs (480-3600 ng/g) and NDL-PCBs (980-35,000 ng/g) were dominant contaminants. Concentrations of PCDDs and PCBs in males were significantly higher than in females. In males, age-dependent accumulation was observed for PCDDs, mono-ortho PCBs and NDL-PCBs. PCDFs and non-ortho PCBs showed no such trends, implying that exposure of seals to these contaminants has been decreasing in recent years. No decreasing temporal trend was observed for PCDDs, mono-ortho PCBs and NDL-PCBs, suggesting that Baikal seals are still exposed to PCDDs and PCBs. TEQs of PCDDs and mono-ortho PCBs in seals collected in 2005 accounted for 62-77% of total TEQs. The TEQ levels in 40% of the specimens exceeded the threshold level for immunosuppression observed in harbor seals (209 pg/g). (C) 2008 Elsevier Ltd. All rights reserved.
  • M. Udaka, T. Ikemoto, H. Zenke, S. Takahashi, V. B. Batoev, E. A. Petrov, S. Tanabe
    MARINE POLLUTION BULLETIN 58 (2) 290 - 294 0025-326X 2009/02 [Peer-reviewed]
     Scientific journal
  • Tetsuro Agusa, Suguru Inoue, Takashi Kunito, Tu Binh Minh, Nguyen Ngoc Ha, Nguyen Phuc Cam Tu, Pham Thi Kim Trang, Hisato Iwata, Pham Hung Viet, Bui Cach Tuyen, Shinsuke Tanabe
    International Journal of Environmental Studies 66 (1) 49 - 57 0020-7233 2009/02 [Peer-reviewed]
     Scientific journal 
    Groundwater contamination by arsenic is a serious environmental problem in the world. Yet there have been few studies conducted in Southeast Asian countries. This article surveys arsenic contamination in groundwater and residents from Vietnam, and is based on our previous studies. Samples of groundwater (n = 118), human hair (n = 59), and urine (n = 100) were collected in the Red River and Mekong River Deltas during 2001-2004. Arsenic was detected in most of the groundwater samples, and its level ranged from < 0.1 to 486 μg/l. Elevated concentrations of arsenic were observed in groundwater at some locations in Ha Nam (up to 486 μg/l) in the Red River Delta and Dong Thap (up to 411 μg/l) in the Mekong River Delta. Remarkably, about 33% of these groundwater samples exceeded the WHO drinking water guideline of 10 μg/l. These results suggest that arsenic contamination in groundwater may be widely present in both the Red River and Mekong River Deltas, Vietnam. A significant positive correlation was observed between arsenic concentrations in groundwater and human hair. Arsenic speciation of human urine revealed the presence of inorganic arsenic, and these concentrations positively correlated with arsenic levels in groundwater. Thus, it is likely that residents in our study areas are chronically exposed to arsenic through drinking groundwater, suggesting that there is a health risk from arsenic in Vietnam.
  • Junko Fujihara, Tetsuro Agusa, Junko Tanaka, Yoshimi Fujii, Tamami Moritani, Masanori Hasegawa, Hisato Iwata, Shinsuke Tanabe, Haruo Takeshita
    FORENSIC TOXICOLOGY 27 (1) 41 - 44 1860-8965 2009/02 [Peer-reviewed]
     Scientific journal 
    Arsenic trioxide (ATO) is an effective therapeutic agent for acute promyelocytic leukemia (APL). In the present study, the concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and arsenic compounds [(dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), As(V), and As(III)] in urine of an APL patient were determined during ATO treatment. The concentrations of 8-OHdG, DMA, and MMA were increased, especially during the fi rst consolidation therapy. Signifi cant positive correlations were observed between concentrations of 8-OHdG and DMA, between concentrations of 8-OHdG and MMA, and between concentrations of 8-OHdG and the sum of arsenic compounds. The present study supports the idea that urinary 8-OHdG can be a marker for arsenic poisoning, when it is detected together with DMA and MMA. In addition, this study is the fi rst to show the relationship between 8-OHdG and levels of arsenic compounds in urine of an APL patient being treated with ATO.
  • Tatsuya Kunisue, Shinsuke Tanabe
    CHEMOSPHERE 74 (7) 950 - 961 0045-6535 2009/02 [Peer-reviewed]
     Scientific journal 
    An analytical method was developed to measure tri- to octa-chlorinated OH-PCBs and pentachlorophenol (PCP) in the whole blood. Further, baseline data on the levels and profiles of these phenolic compounds in Japanese mammals (human, cat, dog, raccoon dog, and northern fur seal) and birds (black-tailed gull, common cormorant, and jungle crow) were obtained. Eighteen identifiable and fifty unknown peaks of OH-PCBs were detected and the major congeners identified were 4'OH-CB101/120, 4OH-CB107/4'OH-CB108, 4OH-CB146, 4OH-CB178, 4OH-CB187, 4'OH-CB172, 4OH-CB202, and 4'OH-CB199. Relatively higher concentrations of OH-PCBs were found in animal species than humans; OH-PCB levels in dog, raccoon dog, black-tailed gull, and common cormorant blood were one order of magnitude higher than in humans. Penta-to hepta-chlorinated OH-PCB congeners were predominant in human blood, but profiles of OH-PCBs in other animals widely varied by species. Elevated composition of tri- and tetra-chlorinated OH-PCBs in cat blood and octa-chlorinated OH-PCBs in dog and raccoon dog blood were observed. In cat blood, elevated PCP concentration was also found. When concentration ratios of OH-PCBs to PCBs were calculated in all the animal blood, the ratios in dog, raccoon dog, and cat were notably higher than in other species. These results indicate that animals other than humans, especially cat and canine species such as dog and raccoon dog, might be at risk from OH-PCBs. (C) 2008 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Takashi Kunito, Tu Binh Minh, Pham Thi Kim Trang, Hisato Iwata, Pham Hung Viet, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 157 (2) 396 - 403 0269-7491 2009/02 [Peer-reviewed]
     Scientific journal 
    This study investigated the status of arsenic (As) exposure from groundwater and rice, and its methylation capacity in residents from the Red River Delta, Vietnam. Arsenic levels in groundwater ranged from <1.8 to 486 mu g/L Remarkably, 86% of groundwater samples exceeded WHO drinking water guideline of 10 mu g/L Also, estimated inorganic As intake from groundwater and rice were over Provisional Tolerable Weekly Intake (15 mu g/week/kg body wt.) by FAO/WHO for 92% of the residents examined. Inorganic As and its metabolite (monomethylarsonic acid and dimethylarsinic acid) concentrations in human urine were positively correlated with estimated inorganic As intake. These results suggest that residents in these areas are exposed to As through consumption of groundwater and rice, and potential health risk of As is of great concern for these people. Urinary concentration ratios of dimethylarsinic acid to monomethylarsonic acid in children were higher than those in adults, especially among men, indicating greater As methylation capacity in children. (C) 2008 Elsevier Ltd. All rights reserved.
  • Tomohiko Isobe, Hiroko Oda, Nozomi Takayanagi, Tatsuya Kunisue, Hiroaki Komori, Norimasa Arita, Norifumi Ueda, Masato Nose, Taketo Yamada, Shin Takahashi, Shinsuke Tanabe
    ENVIRONMENTAL CHEMISTRY 6 (4) 328 - 333 1448-2517 2009 [Peer-reviewed]
     Scientific journal 
    Residue levels of hexabromocyclododecanes (HBCDs) were measured using LC-MS/MS in the Japanese human adipose tissue samples collected during 2003-2004 from Ehime prefecture (n=26) and Kanto region (n = 9) of Japan. Concentrations of HBCDs (0.85 39 ng g(-1) lipid) in the adipose tissue samples were 1 2 orders of magnitude lower than those of organochlorines (OCs). Regional differences between HBCD levels in Ehime prefecture and Kanto region were not significant. No age-dependent accumulation of HBCDs was observed. HBCD levels in men were significantly higher than those in women. Significant positive correlation between polybrominated diphenyl ethers (PBDEs) and HBCDs implies similar routes of exposure to these contaminants for Japanese citizens. alpha-HBCD was predominant among the three isomers, which is consistent with the other reports on bioaccumulation of alpha-HBCD in higher trophic animals.
  • ヒ素代謝に関与するAS3MT M287T多型はアジア人特異的低変異性を示す
    藤原純子, 阿草哲郎, 竹下治男, 福島美貴子, 中島たみ子, 岩田久人, 田辺信介
    DNA多型 17 169 - 172 2009 [Peer-reviewed]
  • 真柄真美, 田島木綿子, 山田 格, 磯部友彦, 高橋 真, 田辺信介, 島田章則
    日本獣医師会雑誌 62 (2) 155 - 160 0446-6454 2009 [Peer-reviewed]
  • Gnanasekaran Devanathan, Annamalai Subramanian, Masayuki Someya, Agus Sudaryanto, Tomohiko Isobe, Shin Takahashi, Paromita Chakraborty, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 157 (1) 148 - 154 0269-7491 2009/01 [Peer-reviewed]
     Scientific journal 
    The present study was carried out to understand the current contamination status of organochlorine compounds (OCs) in human breast milk from three metropolitan cities in India (New Delhi, Mumbai and Kolkata). Among the OCs analyzed, DDTs were predominant followed by HCHs and PCBs. CHLs and HCB levels were much lower. Contamination patterns were different in human milk found in our previous study in Chennai, a metropolitan city in southern India, indicating region specific exposure routes and variable sources. In comparison with previous data, levels of DDTs and HCHs generally declined with time, implying the effect of various bans and restrictions on their usage. No association between concentrations of OCs and demographic characteristics such as parity and age of mothers was observed which might be due to narrow range of mother's age. Estimated daily intake shows that some infants are exposed to OCs to a greater extent, particularly HCHs than the guideline standard. (C) 2008 Elsevier Ltd. All rights reserved.
  • Ryota Murai, Atsuko Sugimoto, Shinsuke Tanabe, Ichiro Takeuchi
    CHEMOSPHERE 73 (11) 1749 - 1756 0045-6535 2008/12 [Peer-reviewed]
     Scientific journal 
    The measurement of organotins in the various biotas of coastal food webs with stable nitrogen isotope ratios (delta N-15), which increase 3.4 parts per thousand per trophic level, can provide a biomagnification profile of organotins through food web. In this study, various biological samples were collected from three localities in Western Japan between 2002 and 2003 for analyses. Tributyltin (TBT) and triphenyltin (TPT) were still detected with a maximum of 99.5 and 8.7 ng wet weight g(-1), respectively. Unlike TBT, significant biomagnification of TPT through the food web (expressed by delta N-15) was found in all three localities. The log transformed octanol-water partition coefficient (log K-ow) of TPT of 2.11-3.43 was overlapped by, but was slightly lower than, that of TBT of 3.70-4.70. Thus, this study demonstrates that although these chemicals have a log K-ow lower than 5. at least TPT undergoes significant biomagnification through the food web. (C) 2008 Elsevier Ltd. All rights reserved.
  • Kwadwo Ansong Asante, Tetsuro Agusa, Hiroko Mochizuki, Karri Ramu, Suguru Inoue, Tsunemi Kubodera, Shin Takahashi, Annamalai Subramanian, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 156 (3) 862 - 873 0269-7491 2008/12 [Peer-reviewed]
     Scientific journal 
    Trace elements (22) and stable isotope ratios (delta N-15 and delta C-13) were analyzed in marine organisms from shallow (SW) and deep-water (DW) of the East China Sea to understand biomagnification and prey source of trace elements. In the benthic marine organisms from DW, delta N-15 values were negatively correlated with Ba, Cu, Ag, Mo, Sr, As. and Co concentrations. This may be due to the specific accumulation in lower trophic animals and/or the biodilution through the food web in DW. Relationships between delta N-15 and concentrations of Co, Cr, Bi, and Tl in fish and Ag, Bi, V, Hg, and Tl in crustaceans showed positive correlations, suggesting that trophic position was affecting the concentrations of those elements in phyla, with higher trophic animals retaining higher concentrations than the lower trophic animals. Positive correlations between delta C-13 and Rb were observed in marine organisms. Therefore, Rb may be a possible substitute of delta C-13 as tracer of prey source in the East China Sea although further investigation is required. (C) 2008 Elsevier Ltd. All rights reserved.
  • Gan Zhang, Paromita Chakraborty, Jun Li, Pichai Sampathkumar, Thangavel Balasubramanian, Kandasamy Kathiresan, Shin Takahashi, Annamalai Subramanian, Shinsuke Tanabe, Kevin C. Jones
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 42 (22) 8218 - 8223 0013-936X 2008/11 [Peer-reviewed]
     Scientific journal 
    India is of prime interest due to the large past and ongoing use of pesticidal persistent organic pollutants (POPS). Rapid dissipation of POPS to the atmosphere in the tropical climate of India infers an atmospheric outflow of these chemicals. Yet data on POPS in the atmosphere of India are sparse. Passive air samplers consisting of polyurethane foam disks were therefore deployed concurrently at 18 locations and exposed for 6 weeks from July 30, 2006, to September 26, 2006, along the coastal length of India to screen for POPS in the atmosphere. The sampling sites were selected to form categories of urban, rural, and background (mangrove/wetlands) locations. Derived air concentrations (pg/m(3)) ranged as follows: the sum of 28 PCB congeners, 120-1080; DOTS, 16-2950; HCHs, 66-5400; chlordanes, 9-921; endosulfans, 0.45-1120; and the sum of 9 PBDE congeners, 1-181. The highest levels of all the detected POPS (except endosulfan) were observed at the urban sites, indicating the dominant areas of usage and emissions. An urban-rural composition fractionation of PCBs indicates their atmospheric movement. The gamma-HCH levels were more than double those of alpha-HCH, indicating the sporadic use of lindane. DDT concentrations were elevated, at levels comparable to China, but with much higher percentages of p,p'-DDE, reflecting a more 'weathered' feature. Although no dicofol use was recorded in India, the o,p'-/p,p'-DDT ratios were observed to be even higher than in China. Chlordanes showed high trans-/cis-chlordane (TC/CC) ratios, indicative of the current use of technical chlordane and a contribution from heptachlor usage.
  • Sonoko Yamaguchi, Fritzie Tuble Celino, Aki Ito, Tetsuro Agusa, Shinsuke Tanabe, Bui Cach Tuyen, Chiemi Miura, Takeshi Miura
    ECOTOXICOLOGY 17 (8) 772 - 780 0963-9292 2008/11 [Peer-reviewed]
     Scientific journal 
    To estimate the influence of water contamination by arsenic (As) on reproduction of crustaceans in Vietnam, we collected wild freshwater crab Somanniathelphusa pax from the Mekong Delta area in Vietnam, investigated gonadal development, and measured As concentration in hepatopancreas. In female crab, vitellogenesis was delayed in association with the increase of As accumulation in hepatopancreas, whereas there was no significant correlation between testicular development and As accumulation in male crab. To clarify the effects of As on gonadal development of crustaceans, we investigated the effects of oral As administration on gonadal development in Japanese freshwater crab Geothelphusa dehaani. In male crab, the occurrence of spermatids and spermatozoa were predominantly observed in the control group, whereas the occurrence of spermatocytes increased after administration of 10 mu g/crab As for 3 months. On the other hand, in females, secondary yolk globule stages mainly occupied ovary of the control group. However, the primary yolk globule stage gradually increased after 10 mu g/crab As administration. Together these results indicate that it is possible that As contamination in water or food causes the delay of spermatogenesis and vitellogenesis in crustaceans.
  • Lin Tao, Jing Ma, Tatsuya Kunisue, E. Laurence Libelo, Shinsuke Tanabe, Kurunthachalam Kannan
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 42 (22) 8597 - 8602 0013-936X 2008/11 [Peer-reviewed]
     Scientific journal 
    The occurrence of perfluorinated compounds (PFCs) in human blood is known to be widespread; nevertheless, the sources of exposure to humans, including infants, are not well understood. In this study, breast milk collected from seven countries in Asia was analyzed (n = 184) for nine PFCs, including perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA). In addition, five brands of infant formula (n = 21) and 11 brands of dairy milk (n = 12) collected from retail stores in the United States were analyzed, for comparison with PFC concentrations previously reported for breast milk from the U.S. PFOS was the predominant PFC detected in almost all Asian breast milk samples, followed by perfluorohexanesulfonate (PFHxS) and PFOA. Median concentrations of PFOS in breast milk from Asian countries varied significantly; the lowest concentration of 39.4 pg/mL was found in India, and the highest concentration of 196 pg/mL was found in Japan. The measured concentrations were similar to or less than the concentrations previously reported from Sweden, the United States, and Germany (median, 106-166 pg/mL). PFHxS was found in more than 70% of the samples analyzed from Japan, Malaysia, Philippines, and Vietnam, at mean concentrations ranging from 6.45 (Malaysia) to 15.8 (Philippines) pg/mL. PFOA was found frequently only in samples from Japan; the mean concentration for that country was 77.7 pg/mL. None of the PFCs were detected in the infant-formula or dairy-milk samples from the U.S. except a few samples that contained concentrations close to the limit of detection. The estimated average daily intake of PFOS by infants from seven Asian countries, via breastfeeding, was 11.8 +/- 10.6 ng/kg bw/ day; this value is 7-12 times higher than the estimated adult dietary intakes previously reported from Germany, Canada, and Spain. The average daily intake of PFOA by Japanese infants was 9.6 +/- 4.9 ng/kg bw/day, a value 3-10 times greater than the estimated adult dietary intakes reported from Germany and Canada. The highest estimated daily intakes of PFOS and PFOA by infants from seven Asian countries studied were 1-2 orders of magnitude below the tolerable daily intake values recommended by the U.K. Food Standards Agency.
  • Agus Sudaryanto, Natsuko Kajiwara, Oyuna V. Tsydenova, Tomohiko Isobe, Hongxia Yu, Shin Takahashi, Shinsuke Tanabe
    CHEMOSPHERE 73 (10) 1661 - 1668 0045-6535 2008/11 [Peer-reviewed]
     Scientific journal 
    Fourteen PBDE congeners from mono- to deca-BDE were determined in breast milk of primiparous mothers from two locations in East China, i.e. Nanjing (n =9), an urban area, and Zhoushan (n - 10). a semi rural coastal area. PBDEs were detected in all the human breast milk samples of the present study, indicating that general Population in these two locations are widely exposed to these pollutants. Relatively higher concentrations of PBDEs were found in the milk of mothers from Nanjing than Zhoushan, suggesting the existence of significant sources of PBDEs in urban areas. PBDE levels in the present study were similar to those in European countries, but one or two orders of magnitude lower than in North America. Except for BDE-3, all congeners from di- to deca-BDE were detected in the samples of the present study. BDE-209, a congener considered to have less bioavailability, was detected in about 50% of the samples at concentrations higher than that of other congeners. Other higher brominated congeners, such as BDE-153, -197 and -207, were also prominent in the present study, which is different from the pattern generally observed in previous studies on human milk as well as biota samples. These results may indicate that the inhabitants of Nanjing and Zhoushan are exposed to location specific sources of PBDEs. (C) 2008 Elsevier Ltd. All rights reserved.
  • Nakayama, K, Iwata, H, Tao, L, Kannan, K, Imoto, M, Kim, E. Y, Tashiro, K, Tanabe, S
    Environmental Toxicology and Chemistry 27 (1) 2378 - 2386 2008/11 [Peer-reviewed]
  • Natsuko Kajiwara, Satoko Kamikawa, Masao Amano, Azusa Hayano, Tadasu K. Yamada, Nobuyuki Miyazaki, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 156 (1) 106 - 114 0269-7491 2008/11 [Peer-reviewed]
     Scientific journal 
    Polybrominated diphenyl ethers (PBDEs) and organochlorine compounds (OCs) were determined in the blubber of 55 melon-headed whales (Peponocephala electra) mass stranded along the Japanese coasts since 1982. DDTs and PCBs were predominant in all the specimens investigated. In whales that died during the latest event in 2006, concentrations of PBDEs (190-510 ng/g lipid wt) were approximately two orders of magnitude lower than DDTs and PCBs, but comparable with HCHs and HCB. Maternal transfer of PBDEs to offspring through the whole reproductive process was estimated to be 85% of the mother's body burden, while that occurring during gestation was much lower (2.6-3.5%). Concentrations of PCBs, DDTs, and HCB were lower in melon-headed whales stranded after the year 2000 than those stranded in 1982, whereas PBDE and CHL levels showed a temporal increase during the past 20 years, suggesting that the peak of their usage and contamination occurred after the year 1982. (C) 2008 Elsevier Ltd. All rights reserved.
  • Kimberly Hart, Kurunthachalam Kannan, Tomohiko Isobe, Shin Takahashi, Tadasu K. Yamada, Nobuyuki Miyazaki, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 42 (19) 7132 - 7137 0013-936X 2008/10 [Peer-reviewed]
     Scientific journal 
    As a result of the phase-out of production of perfluorooctanesulfonyl-based compounds by a major producer, concentrations of perfluorooctanesulfonate (PFOS) in marine mammals from North American and European coastal waters have been declining since the early 2000s. Nevertheless, temporal trends in perfluorochemical (PFC) concentrations in marine mammals from Asian coastal waters have not been examined. In this study, PFCs were determined in livers of melon-headed whales (Peponocephala electra) collected along the coast of Japan, from three mass strandings that occurred during the past 25 years. Concentrations of nine PFCs were determined in livers of 48 melon-headed whales that were collected during strandings in 1982, 2001/2002, and 2006. In addition, concentrations in liver tissues obtained from two pregnant females and their fetuses were compared for determination of transplacental transfer rates of PFCs during gestation. PFOS and perfluorooctanesulfonamide (PFOSA) were the predominant PFCs found in livers of melon-headed whales collected in 1982 (n = 22). PFOS, PFOSA, perfluoroundecanoate (PFUnDA), perfluorododecanoate (PFDoDA), perfluorodecanoate (PFDA), and perfluorononanoate (PFNA) were found in whales collected in 2001/2002 In = 21) and in 2006 (n = 5). Concentrations of PFOS and PFOSA were approximately 10-fold higher in 2001/2002 than in 1982. Whereas concentrations of PFOSA then declined by 2-fold from 2001/2002 to 2006, concentrations of PFOS and perfluorocarboxylates did not decline after 2001/2002. Conversely, concentrations of PFNA and PFDA increased significantly from 2001/2002 to 2006. The proportion of perfluoroalkylsulfonates in total PFC concentrations decreased from 75% in 1982 to 51% in 2006. Conversely,the contribution of perfluorocarboxylates to total PFC concentrations increased from 25% in 1982 to 49% in 2006. PFUnDA was the major perfluorocarboxylate found in whale livers collected after 2000. Analysis of paired samples of mother-fetus demonstrated that the transplacental transfer rates of PFCs were higher than those for PCBs and PBDEs.
  • Kimberly Hart, Kurunthachalam Kannan, Lin Tao, Shin Takahashi, Shinsuke Tanabe
    SCIENCE OF THE TOTAL ENVIRONMENT 403 (1-3) 215 - 221 0048-9697 2008/09 [Peer-reviewed]
     Scientific journal 
    Perfluorinated chemicals (PFCs) have emerged as global environmental contaminants. Studies have reported the widespread occurrence of PFCs in biota from marine coastal waters and in remote polar regions. However, few studies have reported the distribution of PFCs in biota from offshore waters and open oceans. In this study, concentrations of nine PFCs were determined in the livers of 60 skipjack tuna (Katsuworius pelamis) collected from offshore waters and the open ocean along the Pacific Rim, including the Sea of Japan, the East China Sea, the Indian Ocean, and the Western North Pacific Ocean, during 1997-1999. At least one of the nine PFCs was found in every tuna sample analyzed. Overall, perfluorooctanesulfonate (PFOS) and perfluoroundecanoic acid (PFUnDA) were the predominant compounds found in livers of tuna at concentrations of <1-58.9 and <1-31.6 ng/g, wet wt, respectively. Long-chain perfluorocarboxylates such as perfluorodecanoic acid (PFDA) and perfluorododecanoic acid (PFDoDA) were common in the tuna livers. In livers of tuna from several offshore and open-ocean locations, concentrations of PFUnDA were greater than the concentrations of PFOS. The profiles and concentrations of PFCs in tuna livers suggest that the sources in East Asia are dominated by long-chain perfluorocarboxylates, especially PFUnDA. High concentrations of PFUnDA in tuna may indicate a shift in sources of PFCs in East Asia. The spatial distribution of PFOS in skipjack tuna reflected the concentrations previously reported in seawater samples from the Pacific and Indian Oceans, suggesting that tuna are good bioindicators of pollution by PFOS. Despite its predominance in ocean waters, PFOA was rarely found in tuna livers, indicative of the low bioaccumulation potential of this compound. Our study establishes baseline concentrations of PFCs in skipjack tuna from the oceans of the Asia-Pacific region, enabling future temporal trend studies of PFCs in oceans. (C) 2008 Elsevier B.V. All rights reserved.
  • James C. W. Lam, Margaret B. Murphy, Yuan Wang, Shinsuke Tanabe, John P. Giesy, Paul K. S. Lam
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 42 (16) 6296 - 6302 0013-936X 2008/08 [Peer-reviewed]
     Scientific journal 
    Organohalogen compounds, the pesticides aldrin, dieldrin, endrin, hexachlorobenzene, mirex, Sigma chlordanes, Sigma DDTs, Sigma heptachlors, Sigma toxaphenes, and the industrial chemicals Sigma PCBs and Sigma PBDEs, as well as total dioxin-like equivalents (TEQ(H4IIE-luc), were measured in eggs of two Ardeid species, the little egret (Egretta garzetta) and black-crowned night heron (Nycticorax nycticorax) from three port cities along the South China coast: Hong Kong, Xiamen, and Quanzhou. Sigma DDTs was the predominant and most abundant residue, occurring at concentrations ranging from 2.7 x 10(3) to 8.7 x 10(4) ng/g lipid wt. The greatest concentrations of the studied compounds were observed in eggs collected from Hong Kong, with the exception of Sigma DDTs, which occurred at the greatest concentrations in eggs from Quanzhou Bay and Xiamen Harbor. Concentrations of Sigma PBDEs were greater in eggs from Quanzhou Bay and Xiamen Harbor, possibly because of rapid industrialization in these areas. Total concentrations of dioxin-like PCB toxic equivalents (TEQs), measured as the aryl hydrocarbon receptor (AhR)mediated responses of the H4IIE-luc bioassay (TEQ(H4IIE-luc)), were greatest in Hong Kong samples. A risk assessment of the relatively great concentrations of Sigma DDEs and dioxin-like (coplanar) PCBs in the eggs (threshold levels: 2.8 mu g/g wet wt. and 5 pg/g wet wt., respectively) predicted that concentrations of these compounds would be expected to affect some proportion of the Ardeid populations studied.
  • Sokichi Takagi, Furnie Adachi, Keiichi Miyano, Yoshihiko Koizumi, Hidetsugu Tanaka, Mayurni Mimura, Isao Watanabe, Shinsuke Tanabe, Kurunthachalam Kannan
    CHEMOSPHERE 72 (10) 1409 - 1412 0045-6535 2008/08 [Peer-reviewed]
     Scientific journal 
    Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) have been recognized as emerging environmental pollutants because of their ubiquitous occurrence in the environment, biota, and humans. PFOS and PFOA have been detected in water in Japan. Nevertheless, occurrence of PFOS and PFOA in potable water from municipal water treatment plants is not clearly known. We analyzed PFOS and PFOA in raw and tap water samples collected from 14 drinking water treatment plants in winter and summer seasons in Osaka to determine the concentrations of PFOS and PFOA in raw and potable tap water samples. PFOS and PFOA were detected in all raw water samples. Concentration ranges of PFOS and PFOA in raw water were 0.26-22 ng/l and 5.2-92 ng/l, respectively. Whereas the concentrations PFOS in raw water from Osaka were similar to those in other areas in Japan, the concentrations of PFOA were higher than in other areas. Concentration ranges of PFOS and PFOA in potable tap water were 0.16-22 ng/l and 2.3-84 ng/l, respectively. There were positive correlations between PFC concentrations in raw water and tap water samples. Therefore, the removal efficiency of PFCs by the present water treatment may be low. Based on the current action value reported by U.S. Environmental Protection Agency, PFOA concentrations found in tap water in Osaka is not expected to pose health risks. (C) 2008 Elsevier Ltd. All rights reserved.
  • Milene Rato, Miguel B. Gaspar, Shin Takahashi, Shinichi Yano, Shinsuke Tanabe, Carlos Barroso
    MARINE POLLUTION BULLETIN 56 (7) 1323 - 1331 0025-326X 2008/07 [Peer-reviewed]
     Scientific journal 
    Imposex and organotin (OT) tissue contamination of the netted whelk Nassanus reticulatus (L.) were assessed in the continental shelves around the main estuaries of the central coast of Portugal (Lisbon: Tagus estuary; Setubal: Sado estuary) and the main coastal lagoon in the Southern of Portugal (Faro: Ria Formosa). Pollution levels were higher in areas of more intense boat traffic and shipyard activities and imposex showed a clear decreasing gradient from the estuaries to the offshore, in relation to a similar gradient of tissue contamination by tributyltin. Remarkably, imposex was extensively spread over the adjacent continental shelves of Tagus and Sado estuaries. The current work shows that TBT pollution is undoubtedly a matter of concern not only for the above estuaries where harbours are implanted but also for the adjacent continental shelves, regardless the massive dilution of contaminants that may occur in these deeper areas. (c) 2008 Elsevier Ltd. All rights reserved.
  • Tatsuya Kunisue, Yumi Higaki, Tomohiko Isobe, Shin Takahashi, Annamalai Subramanian, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 154 (2) 272 - 282 0269-7491 2008/07 [Peer-reviewed]
     Scientific journal 
    The present study determined concentrations and patterns of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in specimens of open sea, and Japanese coastal and inland avian species, which have been stored in the Environmental Specimen Bank of Ehime University (es-Bank), to examine the spatial trends. PBDEs and PCBs were detected in all the muscle samples analyzed, suggesting that PBDE pollution has spread even to the remote open sea areas, as in the case of PCBs. Japanese coastal and inland birds accumulated higher concentrations of PBDEs than open sea birds. In addition, higher PBDE/PCB concentration ratios were observed in Japanese coastal and inland birds than in open sea birds, indicating the input of PBDEs into the Japanese terrestrial environment. Compositions of PBDEs varied among avian species with a predominance of BDE47 or BDE153. This could be due to differences in their habitat, food habit and/or biotransformation capacity of PBDEs. (C) 2007 Elsevier Ltd. All rights reserved.
  • Tokutaka Ikemoto, Nguyen Phuc Cam Tu, Michio X. Watanabe, Noboru Okuda, Koji Omori, Shinsuke Tanabe, Bui Cach Tuyen, Ichiro Takeuchi
    CHEMOSPHERE 72 (1) 104 - 114 0045-6535 2008/05 [Peer-reviewed]
     Scientific journal 
    The present study elucidated the biomagnification profiles of persistent organic pollutants (POPs) through a tropical aquatic food web of Vietnam based on trophic characterization using stable nitrogen analysis. Various biological samples collected from the main stream of the Mekong Delta were provided for the analysis for both POPs, and stable nitrogen and carbon isotope ratios. Of the POPs analyzed, dichlorodiphenyltrichloroethane and its metabolites (DDTs) were the predominant contaminants with concentrations ranging from 0.058 to 12 ng/g wet weight, followed by polychlorinated biphenyls (PCBs) at 0.017-8.9 ng/g, chlordane compounds (CHLs) at 0.0043-0.76 ng/g, tris4-chlorophenyl methane (TCPMe) at N.D.-O.26 ng/g, hexachlorocyclohexane isomers (HCHs) at N.D.-0.20 ng/g and hexachlorobenzene (HCB) at 0.0021-0.096 ng/g. Significant positive increases of concentrations in DDTs, CHLs, and TCPMe against the stable nitrogen ratio (delta N-15) were detected, while, concentrations of HCHs and HCB showed no significant increase. The slopes of the regression equations between the log-transformed concentrations of these POPs and delta N-15 were used as indices of biomagnification. The slopes of the POPs for which positive biomagnification was detected ranged from 0.149 to 0.177 on a wet weight basis. The slopes of DDTs and CHLs were less than those reported for a marine food web of the Arctic Ocean, indicating that less biomagnification had occurred in the tropical food web. Of the isomers of CHLs, unlike the studies of the Arctic Ocean, oxychlordane did not undergo significant biomagnification through the food web of the Mekong Delta. This difference is considered to be due to a lack of marine mammals, which might metabolize cis- and trans-chlordane to oxychlordane, in the Mekong Delta ecosystem. The biomagnification profile of TCPMe is reported for the first time in the present study. (C) 2008 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Kozue Takagi, Reiji Kubota, Yasumi Anan, Hisato Iwata, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 153 (1) 127 - 136 0269-7491 2008/05 [Peer-reviewed]
     Scientific journal 
    Concentrations of total arsenic (As) and individual compounds were determined in green and hawksbill turtles from Ishigaki Island, Japan. In both species, total As concentrations were highest in muscle among the tissues. Arsenobetaine was a major compound in most tissues of both turtles. High concentrations of trimethylarsine oxide were (]elected in hawksbill turtles. A significant negative correlation between standard carapace length (SCL), an indicator of age, and total As levels in green turtles was found. In contrast, the levels increased with SCL of hawksbill turtles. Shifts in feeding habitats with growth may account for such a growth-dependent accumulation of As. Although concentrations of As in marine sponges, the major food of hawksbill turtles are not high compared to those in algae eaten by green turtles, As concentrations in hawksbill turtles were higher than those in green turtles, indicating that hawksbill turtles may have a specific accumulation mechanism for As. (C) 2007 Elsevier Ltd. All rights reserved.
  • Hiroshi Ishibashi, Hisato Iwata, Eun-Young Kim, Lin Tao, Kurunthachalam Kannan, Shinsuke Tanabe, Valeriy B. Batoev, Evgeny A. Petrov
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 42 (7) 2302 - 2308 0013-936X 2008/04 [Peer-reviewed]
     Scientific journal 
    To investigate the biological effects of perfluorochemicals (PFCs) and to identify biomarkers of exposure to PFCs, this study focused on the effects mediated by peroxisome proliferator-activated receptor alpha (PPAR alpha) in Baikal seals (Pusa sibirica). We cloned a full-length cDNA encoding PPAR alpha from the liver of Baikal seal, which has a deduced open reading frame of 468-amino acid residues with a predicted molecular mass of 52.2 kDa. Comparison of the amino-acid sequence of Baikal seal PPAR alpha with that of other mammalian PPAR alpha showed considerable similarities with PPAR alpha of dog (97%), human (95%), rat (92%), and mouse (91%). The quantitative real-time RTPCR analyses of tissues from Baikal seals revealed that PPAR alpha mRNAs were primarily expressed in the liver, kidney, heart, and muscle. The hepatic expression levels of PPAR alpha mRNA showed a positive correlation with the expression levels of immunochemically detected cytochrome P450 (CYP) 4A-like protein, indicating that the PPAR alpha-CYP4A signaling pathway in Baikal seal is likely conserved. This study also developed an in vitro PPAR alpha reporter gene assay using African green monkey kidney CV-1 cells transiently transfected with Baikal seal PPAR alpha cDNA expression vector and a reporter vector containing a peroxisome proliferator-responsive element. The in vitro reporter gene assay displayed significant response to clofibrate, which is a known PPAR alpha agonist in humans and rodents. Treatment with perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), or perfluorooctane sulfonate (PFOS) induced PPAR alpha-mediated transcriptional activity in a dose-dependent manner, showing the lowest-observed-effect concentrations of 62.5, 125, 125, 62.5, and 125 mu M, respectively. In the livers of wild Baikal seals, expression levels of PPAR alpha mRNA showed a significant positive correlation with PFNA levels. Moreover, expression of hepatic CYP4A-like protein was significantly correlated with the hepatic concentrations of PFNA and PFDA. These results suggest modulation of the PPAR alpha-CYP4A signaling pathway by PFCs in the wild Baikal seals. Our study demonstrates that the PPAR alpha-mediated response may be a useful biomarker to evaluate potential biological effects of PFCs in wildlife.
  • Hiroshi Ishibashi, Hisato Iwata, Eun-Young Kim, Lin Tao, Kurunthachalam Kannan, Masao Amano, Nobuyuki Miyazaki, Shinsuke Tanabe, Valeriy B. Batoev, Evgeny A. Petrov
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 42 (7) 2295 - 2301 0013-936X 2008/04 [Peer-reviewed]
     Scientific journal 
    Concentrations of perfluorochemicals (PFCs) including perfluoroalkylsulfonates (PFSAs) and perfluoroalkylcarboxylates (PFCAs) were determined in liver and serum of Baikal seals (Pusa sibirica) collected from Lake Baikal, Russia in 2005. Among the 10 PFC compounds measured, perfluorononanoic acid (PFNA, 3.3-72 ng/g wet wt) concentrations were the highest in liver, followed by perfluorooctanesulfonate (PFOS, 2.6-38 ng/g). The accumulation profile of long-chain (C7-C12) PFCAs in particular, the predominance of PFNA, indicated that 8:2 fluorotelomer alcohol or commercially manufactured PFNA is a major local source of PFCs in Lake Baikal. No gender-related differences in the concentrations of individual PFCs or total PFCs were found. Tissues from pups and juveniles contained relatively higher concentrations of PFCs than tissues from subadults and adults, suggesting that maternal transfer of PFCs is of critical importance, Comparison of concentrations of PFCs in livers and sera collected from the same individuals of Baikal seals revealed that residue levels of PFOS, PFNA, perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA) were significantly higher in liver than in serum. The concentration ratios of PFNA and PFDA between liver and serum were calculated to be 14 and 15, respectively, whereas the ratio of PFOS was 2.4. This suggests preferential retention of both PFNA and PFDA in liver. Concentrations of PFOS, PFNA, and PFDA in liver were significantly correlated with those in serum, whereas concentrations of PFUnDA were not correlated in between the two tissues, suggesting differences in pharmacokinetics among these PFCs. Temporal comparisons of hepatic PFC concentrations in seals collected between 1992 and 2005 showed that the concentrations of PFOS (p = 0.0006), PFNA (p = 0.061) and PFDA (p = 0.017) were higher in animals collected in recent years, indicating ongoing sources of PFC contamination in Lake Baikal.
  • Satoko Murata, Shin Takahashi, Tetsuro Agusa, Nancy J. Thomas, Kurunthachalam Kannan, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 56 (4) 641 - 649 0025-326X 2008/04 [Peer-reviewed]
     Scientific journal 
    Organotin compounds (OTs) including mono- to tri-butyltins, -phenyltins, and -octyltins were determined in the liver of adult sea otters (Enhydra lutris) found dead along the coasts of California, Washington, and Alaska in the USA and Kamchatka, Russia. Total concentrations of OTs in sea otters from California ranged from 34 to 4100 ng/g on a wet weight basis. The order of concentrations of OTs in sea otters was total butyltins >> total octyltins >= total phenyltins. Elevated concentrations of butyltins (BTs) were found in some otters classified under 'infectious-disease' mortality category. Concentrations of BTs in few of these otters were close to or above the threshold levels for adverse health effects. Total butyltin concentrations decreased significantly in the livers of California sea otters since the 1990s. Based on the concentrations of organotins in sea otters collected from 1992 to 2002, the half-lives of tributyltin and total butyltins in sea otters were estimated to be approximately three years. (c) 2008 Elsevier Ltd. All rights reserved.
  • Natsuko Kajiwara, Mafumi Watanabe, Susan Wilson, Tariel Eybatov, Igor V. Mitrofanov, David G. Aubrey, Lev S. Khuraskin, Nobuyuki Miyazaki, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 152 (2) 431 - 442 0269-7491 2008/03 [Peer-reviewed]
     Scientific journal 
    Persistent organic pollutants including organochlorine pesticides, PCBs, and PCDDs/DFs were determined in the blubber of Caspian seals, which died during an outbreak of canine distemper virus in 2000 and 2001. DDTs were the predominant contaminants that ranged from 3.1 to 560 mu g/g lipid. A negative correlation was observed between concentration of contaminants and blubber thickness. During spring, as the blubber layer becomes thin after breeding and moulting, seals may face higher risk due to the increased concentration of organochlorines in their bodies. TEQs in the blubber of Caspian seals (10-340 pg TEQ/g) were lower than those in seals from other locations, suggesting that toxic effects of these contaminants are a deal less in the present population and they are unlikely to be linked to mass mortality. The levels of PCBs and pesticides in Caspian seals, however, comparable to those in other aquatic mammals that have suffered from epizootics, might pose a risk of immunosuppression. (C) 2007 Elsevier Ltd. All rights reserved.
  • Qiming Xian, Karri Ramu, Tomohiko Isobe, Agus Sudaryanto, Xiaohua Liu, Zishen Gao, Shin Takahashi, Hongxia Yu, Shinsuke Tanabe
    CHEMOSPHERE 71 (2) 268 - 276 0045-6535 2008/03 [Peer-reviewed]
     Scientific journal 
    Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) were determined in muscle, liver and eggs of freshwater fishes from the lower reach of the Yangtze River, China. The present study is the first to report HBCD concentrations in the environment of China. The concentrations of PBDEs and HBCDs in muscle of freshwater fishes from the Yangtze River ranged from IS to I 100 ng/g and 12 to 330 ng/g lipid weight (wt.), respectively. When compared with other regions of the world, the contamination of PBDEs in biota could be regarded as moderate, whereas contamination of HBCDs in biota was relatively high. The PBDE congener profiles in fishes of the present Study were markedly different from those observed in freshwater and marine fishes from other regions of the world. In the present study, BDE-15 BDE-28 and BDE-47 were the predominant congeners in the fishes. This particular congener profile in fishes from the Yangtze River revealed that a specific commercial PBDE formulation (probably made in China) might have been used in the Yangtze River Delta region. (c) 2007 Elsevier Ltd. All rights reserved.
  • Nguyen Phuc Cam Tu, Nguyen Ngoc Ha, Tokutaka Ikemoto, Bui Cach Tuyen, Shinsuke Tanabe, Ichiro Takeuchi
    FISHERIES SCIENCE 74 (1) 109 - 119 0919-9268 2008/02 [Peer-reviewed]
     Scientific journal 
    Accumulation profiles of 22 trace elements in abdominal muscle, abdominal exoskeleton and the hepatopancreas of the giant river prawn Macrobrachium rosenbergii were analyzed. The giant river prawn is an indigenous freshwater species from South Vietnam, and is cultured commercially and fished in the wild. Samples were collected from Ho Chi Minh City and the surrounding area (SKEZ, South Key Economic Zone), and from the Mekong River Delta between 2003 and 2005. Highest accumulations of essential (Cu, Se and Mo) and toxic (As, Ag, Cd and Hg) elements were observed in hepatopancreatic tissue, except for Mn, Sr, Sn, Ba and V in the exoskeleton and Rb and Cs in muscle tissue. Spatial differences showed concentrations of Cs and Pb in muscle and Sr in exoskeletons from the SKEZ were higher than those from the Mekong River Delta. The opposite trend was observed for Cr, Se and Sb in muscle, Mo, Sb and Tl in exoskeleton, and Se, Hg, Mo, Cd, Sb, Tl and Bi in the hepatopancreas. These differences in trace element concentrations in prawns likely reflect differences in industrialization and human activities between the two regions of South Vietnam.
  • J. Falandysz, T. Kunito, R. Kubota, M. Gucia, A. Mazur, Jaromir J. Falandysz, S. Tanabe
    JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMINANTS AND AGRICULTURAL WASTES 43 (2) 187 - 192 0360-1234 2008/02 [Peer-reviewed]
     Scientific journal 
    This article reports background concentrations of Ag, Ba, Cd, Co, Cr, Cs, Cu, Ga, Hg, Mn, Mo, Pb, Rb, Sb, Sr, Se, Tl, V and Zn in caps and stalks of M. procera collected from four spatially distant sites across Poland. The elements were determined using inductively coupled plasma-mass spectrometry (ICP-MS), hydride generation atomic absorption spectrometry (HG-AAS) or a cold vapor atomic absorption spectrometry (CV-AAS). Copper, zinc, rubidium, selenium, chromium and cobalt were the most abundant amongst elements determined in this mushroom. Some elements (Cu, Zn, Rb, Se, Pb, Hg, Cd. Mo) occurred at greater concentrations in the caps than stalks of M. procera and some (Ag, Ba, Sr, V, Tl) dominated in the stalks, while for some other this proportion was similar or varied (Mn, Cr, Co, Ga, Sb, Cs) depending on the sampling site. For elements such as copper, zinc, rubidium as well as selenium some spatial similarity in distribution and/or concentration values both in caps and stalks was noted. Cadmium and lead content in caps of M. procera was usually below the European Union tolerance limit value of 2.0 and 3.0 mu g/g dw set for cultivated mushrooms, respectively. These two toxic metals have been found in elevated concentration in M. procera from unpolluted stands outside of Poland as reported by some authors, which implies the possibility of relatively high background levels in this species.
  • Tatsuya Kunisue, Nozomi Takayanagi, Tomohiko Isobe, Shin Takahashi, Susumu Nakatsu, Toshio Tsubota, Keisuke Okumoto, Sumio Bushisue, Kazuyuki Shindo, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 42 (3) 685 - 691 0013-936X 2008/02 [Peer-reviewed]
     Scientific journal 
    The present study investigated concentrations and patterns of brominated flame retardants, such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs), and persistent organochlorines (OCs) in liver and adipose tissues of raccoon dogs (RD: Nyctereutes procyonoides) collected from two metropolises and a local prefecture in Japan during 2001-2006. Relatively high concentrations of PBDEs were found in RD livers, while HBCD levels were the lowest among the measured organohalogen compounds. Among PBDE congeners, BDE 209 was predominant in RDs from all the regions, indicating that pollution derived from the technical decaBDE product is extensive across Japan. On the other hand, concentrations of tetra- to nona-BDE congeners in RDs from a metropolis were significantly higher than those from the other two regions, implying that there were regional differences in the past usage of the technical tetraBDE and octaBDE products. Such a regional difference was also observed for HBCD levels. Lipid-normalized concentration ratios of liver to adipose tissue L/A ratio) for tri to hepta-BDE congeners were lower than 1.0 in the investigated eight RDs, suggesting lipid-dependent accumulation. However, the L/A ratios of BDE 209 exceeded 1.0 in all the specimens, suggesting hepatic retention of this compound. In addition, lipid-dependent accumulation of alpha-HBCD was observed, but the L/A ratios of gamma-HBCD were greater than 1.0 in some specimens. These results indicate that Japanese RDs have been recently exposed to BDE 209 and gamma-HBCD and accumulated both these compounds preferentially in blood-rich organs, probably due to their binding to proteins and/or rapid biotransformation, as reported in experimental rodents.
  • 宇高真行, 池本徳孝, 岩田久人, 高橋 真, Batoev, V. B, Petrov, E. A, 田辺信介
    環境毒性学会誌 11 (2) 117 - 131 1344-0667 2008 [Peer-reviewed]
  • 仲山 慶, 酒井大樹, 北村真一, 須藤明子, 金 恩英, 田辺信介, 岩田久人
    環境毒性学会誌 11 (2) 75 - 81 2008 [Peer-reviewed]
  • Nguyen Phuc Cam Tu, Nguyen Ngoc Ha, Tokutaka Ikemoto, Bui Cach Tuyen, Shinsuke Tanabe, Ichiro Takeuchi
    MARINE POLLUTION BULLETIN 57 (6-12) 858 - 866 0025-326X 2008 [Peer-reviewed]
     Scientific journal 
    The goal of the present study was to examine the specific bioaccumulation of 22 trace elements in muscle, exoskeleton and hepato-pancreas of black tiger shrimp Penaeus monodon from the Mekong River Delta (MRD), and the South Key Economic Zone (SKEZ), South Vietnam. The general tendency in most trace element concentrations among different tissues were hepatopancreas > exoskeleton > muscle. Comparisons of trace element levels in tissues between the two regions showed that concentrations of Se in muscle and As in all three tissues were higher in SKEZ; whereas in MRD, the higher concentrations of most elements such as Mn, Cu, Cd, Ba, Hg, were observed in tissues. These geographical variations in trace element levels may reflect the differences in human activities between the two regions of South Vietnam. The target hazard quotient (THQ) values for trace elements (<1) indicate that local residents are not exposed to potential health risks via the consumption of shrimp. (C) 2008 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Kumiko Nomura, Takashi Kunito, Yasumi Anan, Hisato Iwata, Nobuyuki Miyazaki, Ryo Tatsukawa, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 57 (6-12) 807 - 815 0025-326X 2008 [Peer-reviewed]
     Scientific journal 
    Concentrations of 19 trace elements (V, Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, Hg, and Pb) were determined in the liver of the striped dolphins (Stenella coeruleoalba) collected around Japan during 1977-1982 to examine the sex difference, age dependence, and interrelationships among trace elements. Tissue distribution of trace elements was also investigated in one adult and one fetus specimens. Generally, concentrations of Se, Sr, Ag, Cd, Cs, Ba, Hg, and Pb were higher in the tissues of adult than those of fetus, whereas the opposite trend was observed for Cr and Tl. There were no significant sex differences in the trace element levels in the liver. Significant positive correlations between age (0-26.5 years) and hepatic concentrations were found for Ag, Se, Hg, V, Fe, Pb, and Sr, suggesting their age-dependent accumulation in the liver. In contrast, hepatic concentrations of Mn and Zn decreased with age. Significant positive relationships were observed between Se, and Hg, Ag, V, Fe, and Sr in the liver. (C) 2008 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Kozue Takagi, Hisato Iwata, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 57 (6-12) 782 - 789 0025-326X 2008 [Peer-reviewed]
     Scientific journal 
    Total arsenic (As) and its compounds were determined in liver, kidney, muscle, and stomach contents of green turtles (Chelonia mydas). Total As concentrations in the muscle were higher than those in the kidney and liver. Arsenobetaine (AB) was the predominant compound in all the three tissues and its levels were positively correlated with total As concentrations. This indicates that AB greatly contributes to As accumulation in green turtles. Higher concentrations of remaining As in the sample after extraction were detected in the liver, implying that lipid-soluble or protein bound As compounds accumulate in the liver of green turtles. Total As levels in tissues showed significant negative correlations with standard carapace length. The size-dependence of As accumulation in green turtles may be related to their feeding habit, shifting from carnivore to herbivore at different growth stages. Concentrations of AB and dimethylarsinic acid (DMA) were low in the stomach contents but high in the tissues, implying bioaccumulation of these arsenicals in green turtles. (C) 2008 Elsevier Ltd. All rights reserved.
  • Kei Nakayama, Shin-Ichi Kitamura, Yasunori Murakami, Jun-Young Song, Sung-Ju Jung, Myung-Joo Oh, Hisato Iwata, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 57 (6-12) 445 - 452 0025-326X 2008 [Peer-reviewed]
     Scientific journal 
    Heavy oil contamination is one of the most important environmental issues. Toxicities of polycyclic aromatic hydrocarbons (PAHs), including immune toxicities, are well characterized, however, the immune toxic effects of heavy oil, as a complex mixture of PAHs, have not been investigated. In the present study, we selected Japanese flounder (Paralichthys olivaceus) as a model organism, and observed alteration of immune function by the exposure to heavy oil. To analyze the expression profiles of immune system-related genes, we selected 309 cDNAs from our flounder EST library, and spotted them on a glass slide. Using this cDNA array, alteration of gene expression profiles was analyzed in the kidneys of flounders exposed to heavy oil. Six Japanese flounders (mean body weight: 197 g) were acclimated to laboratory conditions at 19-20 degrees C. Three fish were exposed to heavy oil C (bunker C) at a concentration of 3.8 g/L for 3 days, and the others were kept in seawater without heavy oil and used as the control. After the exposure period, the fish were transferred into control seawater and maintained for 4 days, and then they were dissected and their kidneys were removed. Total RNA was extracted from the kidney samples to use in gene expression analyses. The microarray detected alteration of immune system-related genes in the kidneys of heavy oil-exposed flounders, including down-regulation of immunoglobulin light chain, CD45, major histocompatibility complex class II antigens and macrophage colony-stimulating factor precursor, and up-regulation of interleukin-8 and lysozyme. These results suggest that pathogen resistance may be weakened in heavy oil-exposed fish, causing a subsequent bacterial infection, and then proinflammatory genes may be induced as a defensive response against the infection. Additionally, we found candidate genes for use as biomarkers of heavy oil exposure, such as N-myc downstream regulated gene 1 and heat shock cognate 71 kDa proteins. (c) 2008 Elsevier Ltd. All rights reserved.
  • Kurunthachalam Kannan, Hyo-Bang Moon, Se Hun Yun, Tetsuro Agusa, Nancy J. Thomas, Shinsuke Tanabe
    JOURNAL OF ENVIRONMENTAL MONITORING 10 (4) 552 - 558 1464-0325 2008 [Peer-reviewed]
     Scientific journal 
    Concentrations of organochlorine pesticides (DDTs, HCHs, and chlordanes), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), perfluorinated compounds (PFCs), and 20 trace elements were determined in livers of 3- to 5-year old stranded sea otters collected from the coastal waters of California, Washington, and Alaska (USA) and from Kamchatka (Russia). Concentrations of organochlorine pesticides, PCBs, and PBDEs were high in sea otters collected from the California coast. Concentrations of DDTs were 10-fold higher in California sea otters than in otters from other locations; PCB concentrations were 5-fold higher, and PBDE concentrations were 2-fold higher, in California sea otters than in otters from other locations. Concentrations of PAHs were higher in sea otters from Prince William Sound than in sea otters from other locations. Concentrations of several trace elements were elevated in sea otters collected from California and Prince William Sound. Elevated concentrations of Mn and Zn in sea otters from California and Prince William Sound were indicative of oxidative stress-related injuries in these two populations. Concentrations of all of the target compounds, including trace elements, that were analyzed in sea otters from Kamchatka were lower than those found from the US coastal locations.
  • 二宮 久, 藤田慎二郎, 宇野克之, 泉 喜子, 青木平八郎, 高橋 真, 田辺信介
    環境化学 18 (1) 29 - 42 2008 [Peer-reviewed]
  • Jian Yang, Takashi Kunito, Yasumi Anan, Shinsuke Tanabe, Nobuyuki Miyazaki
    CHEMOSPHERE 70 (7) 1203 - 1210 0045-6535 2008/01 [Peer-reviewed]
     Scientific journal 
    Total and subcellular renal Zn, Cu, Se, Mn, V, Hg, Cd and Ag were determined by a mother-fetus pair of Dall's porpoises (Phocoenoides dalli). All element concentrations in the maternal individual were higher than those in the fetal individual. Most of total renal elements studied were present in the cytosol of both animals. In maternal cytosol, Mn, Hg and Ag were present in high molecular weight substances (HMW); Se was in low molecular weight substances (LMW); Zn, Cu, and Cd were in metallothionein (MT), mostly; and the distribution of V in percentage among the three renal cytosolic fractions was similar. In fetal cytosol, Zn, Mn, Hg, V, Cd, and Ag were present in HMW, Cu was present in MT, mostly. in contrast, Se was observed mostly in both LMW and HMW. MT isoforms were characterized. Three obvious peaks in retention time were found in either the maternal or fetal MT. The highest elemental ion intensities were in the 7.8 min peak for the mother, and in the 4.3 min peak for the fetus, respectively, implying that different NIT isoforms may be closely associated with elemental accumulation between maternal and fetal renal cytosols. (c) 2007 Elsevier Ltd. All rights reserved.
  • Agus Sudaryanto, Natsuko Kajiwara, Shin Takahashi, Muawanah, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 151 (1) 130 - 138 0269-7491 2008/01 [Peer-reviewed]
     Scientific journal 
    The present study reports concentrations of polybrominated diphenyl ethers (PBDEs) and organochlorines (OCs) in human breast milk from Indonesia covering urban, suburban and rural areas. PBDEs were detected in all the samples of the present study with total concentrations ranging from 0.49 to 13 ng/g lipid wt. Geographical distribution showed that concentrations of PBDEs were relatively uniform (p > 0.05) and the levels were in the same order as those in Japan and some European countries, but were one or two order lower than North America. When compared to OCs, the level of total PBDEs was lower. The congener pattern was in accordance with other studies on human matrices, in which BDE-47 was the most abundant congener. Variations of PBDE congeners in human breast milk were further discussed to elucidate the potential exposure source(s) and pathways. (C) 2007 Elsevier Ltd. All rights reserved.
  • Tatsuya Kunisue, Nozomi Takayanagi, Tomohiko Isobe, Shin Takahashi, Masato Nose, Taketo Yamada, Hiroaki Komori, Nonimasa Arita, Norifumi Ueda, Shinsuke Tanabe
    ENVIRONMENT INTERNATIONAL 33 (8) 1048 - 1056 0160-4120 2007/11 [Peer-reviewed]
     Scientific journal 
    The present study determined concentrations of polybrominated diphenyl ethers (PBDEs) and persistent organochlorines (OCs) in Japanese human adipose tissues collected during 2003-2004. Concentrations of PBDEs in adipose tissues were 1-2 orders of magnitude lower than those of OCs. However, observed PBDE congener levels in this study were relatively higher than those in Japanese human adipose tissues collected during 2000 reported previously, while OC levels were comparable to those in specimens collected during 1999 reported by our group. In addition, no age-dependent accumulation of PBDEs was observed, while OC levels except chlordane compounds increased with age. These results indicate recent human exposure to PBDEs in Japan. Among PBDE congeners accumulated in Japanese adipose tissues, BDE-153 was dominant, but this trend was different from those in human milk (BDE-47) and blood (BDE-209) reported previously in Japan, implying the congener-specific kinetics in human bodies. The significant positive correlations between PBDEs and OCs were observed in Japanese adipose tissues, indicating the similar exposure route of these contaminants for Japanese citizens, probably via fish intake. (C) 2007 Elsevier Ltd. All rights reserved.
  • Ana Sousa, Chiho Matsudaira, Shin Takahashi, Shinsuke Tanabe, Carlos Barroso
    MARINE POLLUTION BULLETIN 54 (10) 1645 - 1653 0025-326X 2007/10 [Peer-reviewed]
     Scientific journal 
    Organotin (OT) compounds have been used as biocide agents in antifouling paints since the mid 1960s and are now ubiquitous in the marine environment. Due to their high toxicity to non-target species they were banned from antifouling paints in the European Union in 2003 (2002/62/EC directive). The aim of the present work is to assess any obvious decline of the OT environmental levels at Ria de Aveiro (NW Portugal) after the ban. The organotins - monobutyltin (MBT), dibutyltin (DBT), tributyltin TBT), monophenyltin (MPT), diphenyltin (DPT), triphenyltin (TPT), monoctyltin (MOT), dioctyltin (DOT) and trioctyltin (TOT) - were quantified in the gastropod Nassarius reticulatus, in the mussel Mytilus galloprovincialis and in sediments. Imposex (imposition of male characters on females of gonochorist gastropods) in N. reticulatus was additionally used as a biomarker of TBT pollution. Time comparisons show a slight decrease of imposex between 2003 and 2005 probably as a consequence of the EU ban, though in some cases this trend seems to have started earlier since 2000. The fraction of TBT relatively to its metabolites has been decreasing over the last years but still remains high suggesting that there are still recent inputs of this compound into the study area. (C) 2007 Elsevier Ltd. All rights reserved.
  • Kurunthachalam Kannan, Tetsuro Agusa, Thomas J. Evans, Shinsuke Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 53 (3) 473 - 482 0090-4341 2007/10 [Peer-reviewed]
     Scientific journal 
    Concentrations of 20 trace elements (V, Cr, Mn, Co, Cu, Zn, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, Pb, and Bi) were measured in livers of polar bears (Ursus maritimus) collected from Northern and Western Alaska from 1993 to 2002 to examine differences in the profiles of trace metals between the Beaufort Sea (Northern Alaska) and the Chukchi Sea (Western Alaska) subpopulations in Alaska. Among the trace elements analyzed, concentrations of Cu (50-290 mu g/g, dry wt) in polar bear livers were in the higher range of values that have been reported for marine mammals. Concentrations of Hg in polar bears varied widely, from 3.5 to 99 mu g/g dry wt, and the mean concentrations in polar bears were comparable to concentrations reported previously for several other species of marine mammals. Mean concentrations of Pb and Cd were 0.67 and 1.0 mu g/g dry wt, respectively; these concentrations were lower than levels reported elsewhere for polar bears from Greenland and Canada. Age- and gender-related variations in the concentrations of trace elements in our polar bears were minimal. Concentrations of Hg decreased slowly in samples collected during 1993-2002, whereas Cd and Pb concentrations were found to be stable or slowly increasing, in the livers of Alaskan polar bears. Concentrations of Ag, Bi, Ba, Cu, and Sn were significantly higher in the Chukchi Sea subpopulation than in the Beaufort Sea subpopulation. Concentrations of Hg were significantly higher in the Beaufort Sea subpopulation than in the Chukchi Sea subpopulation. Differences in the profiles and concentrations of Hg, Ag, Bi, Ba, Cu, and Sn suggest that the sources of exposure to these trace elements between Western and Northern Alaskan polar bears are different, in agreement with findings reported earlier for several organic contaminants.
  • Tomohiko Isobe, Karri Ramu, Natsuko Kajiwara, Shin Takahashi, Paul K. S. Lam, Thomas A. Jefferson, Kaiya Zhou, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 54 (8) 1139 - 1145 0025-326X 2007/08 [Peer-reviewed]
     Scientific journal 
    A diastereoisomer (alpha, beta, and gamma) specific analytical method for measuring hexabromocyclododecanes (HBCDs) was developed using liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method developed was applied to analyze blubber of small cetaceans to divulge the distribution and temporal variation of HBCDs in the Asian marine environment. HBCDs were detected in all the blubber samples of finless porpoises (Neophocaena phocaenoides) and Indo-Pacific humpback dolphins (Sousa chinensis) collected from the South China Sea during 1990-2001. Concentrations of HBCDs were higher in humpback dolphins (31-380 ng/g lipid) than in finless porpoises (4.7-55 ng/g lipid), which can be attributed to habitat differences. Average concentrations of alpha-HBCD in finless porpoises increased from 9.5 ng/g lipid in 1990 to 35 ng/g lipid in 2000/01. alpha-HBCD was predominant among the three isomers with some exceptions in finless porpoises collected in 1990. This is the first report on HBCDs contamination in marine mammals from Southeast Asia. (C) 2007 Elsevier Ltd. All rights reserved.
  • Agus Sudaryanto, In Monirith, Natsuko Kajiwara, Shin Takahashi, Philippus Hartono, Muawanah, Koji Omori, Hidetaka Takeoka, Shinsuke Tanabe
    ENVIRONMENT INTERNATIONAL 33 (6) 750 - 758 0160-4120 2007/08 [Peer-reviewed]
     Scientific journal 
    Organochlorines such as PCBs, DDTs, HCHs, CHLs and HCB were determined in pooled whole body homogenized of fish samples collected from five locations during 1998 and 2003 in order to understand their contamination status, temporal and spatial variation in Indonesian waters. PCBs and DDTs were the predominant contaminants with concentrations from 9.7 to 2700 ng/g lipid wt. and 12 to 1100 ng/g lipid wt., respectively, while HCHs (nd-24 ng/g lipid wt.), CHL compounds (nd-81 ng/g lipid wt.) and HCB (0.22-28 ng/g lipid wt.) were one to two orders of magnitude lower. Among the locations, PCBs and CHLs were higher in the samples from highly industrialized and thickly populated-locations, whereas OC pesticides such as DDTs and HCHs were particularly more prominent in suburban and rural areas. Levels of OCs observed in the waters surrounding Java Island were higher than those in Sumatra Island, implying significant use of OCs in highly populated Java Island. Concentrations of PCBs and DDTs in fish from Jakarta Bay were significantly lower in the samples collected in 2003 as compared to fish in 1998, indicating decreasing trend of these compounds in the Indonesian environment. Recent estimated average daily intakes of PCBs (0.81 mu g/person/ day), DDTs (1.1 mu g/person/day), HCHs (0.018 (mu g/person/day), CHLs (0.010 mu g/person/day) were much lower than the threshold values recommended by various agencies, suggesting minimal risk of this compound via fish ingestion to Indonesians. (c) 2007 Elsevier Ltd. All rights reserved.
  • Satoko Niimi, Eun-Young Kim, Hisato Iwata, Michio X. Watanabe, Genta Yasunaga, Yoshihiro Fujise, Shinsuke Tanabe
    COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY 147 (4) 667 - 681 1096-4959 2007/08 [Peer-reviewed]
     Scientific journal 
    Full-length cDNA sequences of cytochrome P450 (CYP) 2C78, 2EI, 3A72, 4A35 and 4V6 isozymes were isolated from a hepatic cDNA library of common minke whale (Balaenoptera acutorostrata). The deduced amino acid sequences of minke whale CYP2C78, 2131, 3A72, 4A35 and 4V6 showed high identities with cattle CYP2C86 (83%), pig CYP2E1 (85%), sheep CYP3A24 (82%), pig CYP4A21 (80%), and human CYP4V2 (76%), respectively. To investigate whether or not these CYP expression levels are altered by contamination of organochlorine contaminants (OCs), mRNA levels of these CYPs in the liver of common minke whale were measured using a quantitative real-time RT-PCR method, and the quantified mRNA levels were employed for the statistical analysis with the residue levels of OCs including PCBs, DDTs (p,p'-DDT, p,p-DDD and p,p'-DDE), chlordanes (cis-chlordane, trans-chlordane, cis-nonachlor, trans-nonachlor and oxychlordane), HCHs (alpha, beta- and gamma-isomers) and hexachlorobenzene that have already been reported elsewhere. Spearman's rank correlation analyses showed no significant correlation between CYP expression levels and each OC level in the common minke whale liver, implying that these environmental chemicals have no potential to alter the expression levels of these CYPs or the residue levels encountered in the whale livers may not reach their transcriptional regulation levels. This suggests that the expression of individual CYPs in the whale liver may be at basal level. Relationships among hepatic mRNA expression levels of these CYP2-4 isozymes together with CYP1A1 and CYP1A2 were also examined. Significant positive correlations were detected among mRNA expression levels of individual CYP isozymes in most cases. These associations indicate that the transcriptional regulation of these CYPs examined in this study maybe reciprocally related. CYP1A1 levels showed a positive correlation with CYP1A2 levels (r=0.64,p < 0.01) indicating that both CYP isozymes were regulated by aryl hydrocarbon receptor activated by endogenous ligands. A strong positive correlation between CYP2C78 and 3A72 (r=0.90, p < 0.001) suggests that expression of these CYP isozyrnes may be under a regulation mechanism of cross-talk in which specific nuclear receptors such as constitutive androstane receptor and pregnane X receptor are involved. The present study indicates that minke whale from the North Pacific may be a model species to investigate the mechanism of basal regulation of these CYPs. (c) 2007 Elsevier Inc. All rights reserved.
  • Karri Ramu, Natsuko Kajiwara, Agus Sudaryanto, Tomohiko Isobe, Shin Takahashi, Annamalai Subramanian, Daisuke Ueno, Gene J. Zheng, Paul K. S. Lam, Hideshige Takada, Mohamad Pauzi Zakaria, Pham Hung Viet, Maricar Prudente, Touch Seang Tana, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 41 (13) 4580 - 4586 0013-936X 2007/07 [Peer-reviewed]
     Scientific journal 
    Mussel samples were used in this study to measure the levels of polybrominated diphenyl ethers (PBDEs) and organochlorines (OCs) in the coastal waters of Asian countries like Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, the Philippines, and Vietnam. PBDEs were detected in all the samples analyzed, and the concentrations ranged from 0.66 to 440 ng/g lipid wt. Apparently higher concentrations of PBDEs were found in mussels from the coastal waters of Korea, Hong Kong, China, and the Philippines, which suggests that significant sources of these chemicals exist in and around this region. With regard to the composition of PBDE congeners, BDE-47, BDE-99, and BDE-100 were the dominant congeners in most of the samples. Among the OCs analyzed, concentrations of DDTs were the highest followed by PCBs > CHILs > HCHs > HCB. Total concentrations of DDTs, PCBs, CHLs, and HCHs in mussel samples ranged from 21 to 58 000, 3.8 to 2000, 0.93 to 900, and 0.90 to 230 ng/g lipid wt., respectively. High levels of DDTs were in mussels from Hong Kong, Vietnam, and China; PCBs were found in Japan, Hong Kong, and industrialized/urbanized locations in Korea, Indonesia, the Philippines, and India; CHLs were found in Japan and Hong Kong; HCHs were found in India and China. These countries seem to play a role as probable emission sources of corresponding contaminants in Asia and, in turn, may influence their global distribution.
  • Tatsuya Kunisue, Takanori Sakiyama, Tadasu K. Yamada, Shin Takahashi, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 54 (7) 963 - 973 0025-326X 2007/07 [Peer-reviewed]
     Scientific journal 
    Levels of hydroxylated polychlorinated biphenyls (OH-PCBs) and PCBs were measured in the brain of melon-headed whales (MW: Peponocephala electra), striped dolphins (SD: Stenella coerideoalba) and finless porpoises (FP: Neophocaena phocaenoides) stranded along the Japanese coast during 2002-2003. Levels of OH-PCBs (including identified and unknown OH-P5CB, -H6CB, -H7CB and O8CB congeners) in the brain of MW, SD and FP were in the range of 20-290, 21-330 and 170-240 pg/g wet wt., respectively. Observed OH-PCB levels were 2-3 orders of magnitude lower than PCBs in the same individuals. OH-PCBs/PCBs ratios in MW, SD and FP brain were lower than those in blood of humans and wildlife and in the brain of polar bears reported previously. OH-PCBs were also detected in maternal and fetal brain of SID (1 pair), suggesting transfer of OH-PCBs into the fetal brain of odontocete cetaceans. When fetus/dam concentration ratios of 0H-PCB congeners detected in maternal and fetal brain were estimated, the values were higher than those of PCB congeners, implying that OH-PCBs in maternal blood could be more easily transferred into fetal brain via placenta than PCBs. (c) 2007 Elsevier Ltd. All rights reserved.
  • Fujiyo Suehiro, Hiroko Mochizuki, Shinji Nakamura, Hisato Iwata, Takeshi Kobayashi, Shinsuke Tanabe, Yoshifumi Fujimori, Fumitake Nishimura, Bui Cach Tuyen, Touch Seang Tana, Satoru Suzuki
    CHEMOSPHERE 68 (8) 1459 - 1464 0045-6535 2007/07 [Peer-reviewed]
     Scientific journal 
    Tributyltin (TBT) is organotin compound that is toxic to aquatic life ranging from bacteria to mammals. This study examined the concentration of TBT in sediment from and near the Mekong River and the distribution of TBT-resistant bacteria. TBT concentrations ranged from <2.4 to 2.4 ng/g (dry wt) in river sediment and <2.4-15 ng g(-1) (dry wt) in harbor sediment. Viable count of total bacteria ranged from 2.0 x 10(4) to 1.4 x 10(7) cfu/g, and counts of TBT-resistant bacteria ranged <1.0 x 10(2) to 2.5 x 10(4) cfu/g. The estimated occurrence rate of TBT-resistant bacteria ranged from <0.01 to 34% and was highest in upstream sites in Cambodia. The occurrences of TBT in the sediment and of TBT-resistant bacteria were unrelated, and chemicals other than TBT might induce TBT resistance. TBT-resistant bacteria were more abundant in the dry season than in the rainy season. Differences in the selection process of TBT-resistant bacteria between dry and rainy seasons were examined using an advection-diffusion model of a suspended solid (SS) that conveys chemicals. The estimated dilution-diffusion time over a distance of 120 km downstream from a release site was 20 days during dry season and 5 days during rainy season, suggesting that bacteria at the sediment surface could be exposed to SS for longer periods during dry season. (C) 2007 Elsevier Ltd. All rights reserved.
  • Jian Yang, Takashi Kunito, Shinsuke Tanabe, Nobuyuki Miyazaki
    ENVIRONMENTAL POLLUTION 148 (2) 669 - 673 0269-7491 2007/07 [Peer-reviewed]
     Scientific journal 
    Liver samples of 22 Dall's porpoises (Phocoenoides dalli) collected off the Sanriku coast of Japan were analyzed for investigation on bioaccumulation of total mercury (Sigma Hg), organic mercury (OrgHg), inorganic mercury (InHg) and selenium (Se). In the liver, detoxification of Hg was evident by transformation of OrgHg. Se showed different Hg detoxification patterns in the liver with a threshold range of hepatic Sigma Hg concentration of about 20-30 mu g/g dry weight. The molar ratios of Se/InHg or Se/Sigma Hg were obviously higher than I when hepatic Sigma Hg levels were less than the range, while both ratios were close to I when Sigma Hg levels were higher than the threshold, suggesting a mechanism by detoxification of OrgHg into less toxic mercuric selenide (HgSe) forms in the latter. (c) 2006 Elsevier Ltd. All rights reserved.
  • Karri Ramu, Natsuko Kajiwara, Tomohiko Isobe, Shin Takahashi, Eun-Young Kim, Byung-Yoon Min, Sung-Ug We, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 148 (2) 562 - 569 0269-7491 2007/07 [Peer-reviewed]
     Scientific journal 
    Blue mussels (Mytilus edulis) from 20 locations along the coastal waters of Korea were analyzed to elucidate the characteristic distribution and contamination status of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), polychlorinated biphenyls (PCBs) and organochlorine pesticides. To our knowledge, this is the first study to report on the contamination status of HBCDs from Korea. PBDEs and HBCDs were found in mussels at levels ranging from 6.6 to 440 and from 6.0 to 500 ng/g lipid wt., respectively. Concentrations of PBDEs in mussels from Korea were higher or comparable to available data in mussels from other countries. Among the organochlorine compounds (OCs) analyzed, levels of PCBs and DDTs were the highest followed by CHLs, HCHs and hexachlorobenzene. For all the compounds, higher concentrations were found in mussels from southeastern coast of Korea. The present study shows the importance of mussels as bioindicators for monitoring contaminants in coastal waters. (c) 2006 Elsevier Ltd. All rights reserved.
  • Nguyen Hung Minh, Tomohiko Isobe, Daisuke Ueno, Keizo Matsumoto, Masayuki Mine, Natsuko Kajiwara, Shin Takahashi, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 148 (2) 409 - 417 0269-7491 2007/07 [Peer-reviewed]
     Scientific journal 
    Brominated flame retardants (BFRs), hexabromocyclododecanes (HBCDs) and polybrominated diethyl ethers (PBDEs) were detected in three sediment cores and six surface sediments of Tokyo Bay, Japan. HBCDs were detected for the first time in this region with concentrations ranging from 0.056 to 2.3 ng/g dry wt, implying their widespread contamination, even though their concentrations were lower than Sigma PBDEs (di- to nona-BDEs) and BDE-209. Levels of these compounds were higher near to the highly populated industrial area of the bay implicating industrial and human activities as sources of these compounds. Sigma PBDEs increased in the sediment layer up to the mid-1990s and decreased afterwards, whereas BDE-209 showed an increasing trend until now, following the usage of different commercial BDE mixtures. HBCDs first appeared in the mid-1970s and increased until today. The annual surficial flux of HBCDs (0.62-2.4 ng/cm(2)/yr) is equal to Sigma PBDEs (0.95-2.6 ng/cm(2)/yr) but lower than that of BDE-209 (17-58 ng/cm(2)/yr). (c) 2007 Elsevier Ltd. All rights reserved.
  • James C. W. Lam, Natsuko Kajiwara, Karri Ramu, Shinsuke Tanabe, Paul K. S. Lam
    ENVIRONMENTAL POLLUTION 148 (1) 258 - 267 0269-7491 2007/07 [Peer-reviewed]
     Scientific journal 
    Concentrations of total polybrominated diphenyl ethers (PBDEs) in Ardeid eggs from Hong Kong, Xiamen and Quanzhou in south China ranged from 140-1000, 30-550 and 140-380 ng g(-1), lipid wt., respectively. There were spatial and interspecies variations in the abundance and congeneric profiles of PBDEs. The different congeneric profiles observed among the study sites may be associated with the developmental phases of the cities, as well as a possible consequence of debromination of BDE209. Marked concentrations of higher-brominated diphenyl ethers (BDEs 183, 196, 197, 206, 207 and 209) were detected in the egg samples from all sites, probably indicating uptake of BDE209 by top predators, and that there is widespread occurrence of BDE209 in south China. Comparisons of egg concentrations of BDEs 47, 99, 153 and 209 with tentative critical concentrations for neurobehavioral effects and oxidative stress indicated some potential risks for BDE99 and BDE209 in the Ardeid populations. (C) 2006 Elsevier Ltd. All rights reserved.
  • Shusaku Hirakawa, Hisato Iwata, Yoko Takeshita, Eun-Young Kim, Tomohiro Sakamoto, Yuka Okajima, Masao Amano, Nobuyuki Miyazaki, Evgeny A. Petrov, Shinsuke Tanabe
    TOXICOLOGICAL SCIENCES 97 (2) 318 - 335 1096-6080 2007/06 [Peer-reviewed]
     Scientific journal 
    This study attempts to relate the 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent (TEQ) level with certain responses including the catalytic activities and expression of hepatic cytochrome P450 (CYP) 1A and CYP1B in wild population of Baikal seal (Pusa sibirica). We isolated full-length CYP1A1, 1A2, and 1B1 cDNAs, which encode proteins of 516, 512, and 543 amino acids, respectively. Immunochemical analysis demonstrated that a cross-reactive protein with polyclonal antibody against rat CYP1A1 or CYP1B1 was detected in the seal liver. Total TEQ levels showed significant positive correlations with expression levels of CYP1A1, 1A2, and 1B1 mRNAs, and further with both CYP1A- and CYP1B-like proteins, indicating chronic induction of these CYP isozymes by TEQs. The 50% effective concentration for CYP1A-like protein induction was estimated to be 65 pg TEQ/g wet weight. To evaluate the potential of congener-specific metabolism, profiles of negative correlations between the concentrations of eachcongener normalized to a relatively recalcitrant congener, PCB169, and CYP1A-like protein levels were also estimated. Significant negative correlations of 2,3,7,8-tetrachlorodibenzofuran and PCB77 to CYP1A-like protein expression may possibly be due to the preferential metabolism of these congeners. Anti-rat CYP1A1 and CYP1B1 antisera equivalently inhibited ethoxyresorufin O-deethylase (EROD) activity in the seal microsomes, suggesting that both CYPs are involved in EROD activity. Hepatic EROD revealed an increasing trend at lower TEQs, but a declining trend at higher levels, implying a catalytic inhibition of CYP1A and CYP1B. Furthermore, ratios of CYP1B1/CYP1A1 mRNA expression levels increased with TEQs, indicating the enhanced risk of carcinogenicity by preferential induction of CYP1B1 by TEQs in the liver.
  • Sonoko Yamaguchi, Chiemi Miura, Aki Ito, Tetsuro Agusa, Hisato Iwata, Shinsuke Tanabe, Bui Cach Tuyen, Takeshi Miura
    AQUATIC TOXICOLOGY 83 (1) 43 - 51 0166-445X 2007/06 [Peer-reviewed]
     Scientific journal 
    To stimate the influence of water contaminants on fish reproduction in the Mekong Delta area, we sampled cultivated male catfish (Pangasianodon hypophthalmus), investigated testicular development, and measured persistent organic pollutants (POPs) and trace element levels in muscle and liver, respectively. Various testes sizes were observed although sampling took place during a short period. Histological analysis revealed that all developmental stages of germ cells were observed in catfish with large testis, whereas only necrotic spermatogonia but no other germ cells were observed in catfish with small testis. In small testis, furthermore, vacuolization and hypertrophy of Sertoli cells were observed. Measurement of POPs in muscle and trace elements in liver demonstrated that there were negative correlations between GSI and the concentrations of Pb, Mo, Rb and As. To clarify possible direct effects of Pb, Mo, Rb and As on spermatogenesis in fish, we investigated the effects of these trace elements on spermatogenesis using in vitro testicular organ culture of Japanese eel (Anguilla japonica). Treatment with each of the trace elements alone did not affect spermatogenesis. However, treatment with 10(-7) M of Pb, 10(-5) and 10(-4) M of Mo, 10(-5) -10(-3) M of Rb or 10(-5) M of As inhibited the spermatogenesis induced by 11-ketotestosterone (11 KT). Furthermore, treatment with 10(-4) M of As in combination with 11KT caused necrosis of testicular fragments. Taken together, these results are consistent with the hypothesis that Ph, Mo, Rb and As can exert inhibitory effects on spermatogenesis in catfish inhabiting the Mekong Delta area. (C) 2007 Elsevier B.V. All rights reserved.
  • Junya Nagayama, Hitoshi Kohno, Tatsuya Kunisue, Kyoichiro Kataoka, Hiroshi Shimomura, Shinsuke Tanabe, Sadanori Konishi
    CHEMOSPHERE 68 (5) 972 - 976 0045-6535 2007/06 [Peer-reviewed]
     Scientific journal 
    We have investigated the effects of prenatal exposure to dioxin-like compounds (PCDDs, PCDFs and dioxin-like PCBs), PCBs and organochlorine pesticides (DDT, HCH, chlordane, HCB and their metabolites) on the incidence of congenital hypothyroidism and/or cretinism in Fukuoka, Japan from 2001 to 2004. Thirty-four positive neonates of the mass-screening for cretinism were classified into three groups by the pediatrician after the reevaluation of the serum TSH level, that is, negative in reevaluation group, hyper thyroid stimulating hormone (TSH) emia group and cretinism group. One-hundred and two negative neonates of the mass-screening were classified into the normal group. Concentrations of these organochlorine compounds in the breast milk of mothers, which were considered as the indicator of prenatal exposures to them, were gradually increased from the normal group to the cretinism group in the four groups and were around two times higher in the cretinism group than in the normal group. According to the case-control study adjusted for the parity and mother's age, odds ratios of PCBs, DDT and HCB were 10 (p = 0.003), 10 (p = 0.003) and 22 (p = 0.004), respectively and in dioxin-like compounds, PCDFs showed the highest odds ratio, 9.8 (p = 0.005). Based upon those findings, these compounds seemed play an important role in the incidence and/or causation of the cretinism. (c) 2007 Elsevier Ltd. All rights reserved.
  • Annamalai Subramanian, Masako Ohtake, Tatsuya Kunisue, Shinsuke Tanabe
    CHEMOSPHERE 68 (5) 928 - 939 0045-6535 2007/06 [Peer-reviewed]
     Scientific journal 
    Mothers' milk from Chermai (formerly Madras), India and three other places Perungudi, the municipal dumping site of south Chennai area (situated at the suburb of Chennai), Chidambaram, a predominantly agricultural town situated 250 kin south of Chermai and Parangipettai, a fishing village 15 km north of Chidambaram, all situated at or near the southeastern Bay of Bengal coast of India were found to contain measurable concentrations of HCHs, DDTs, PCBs, CHLs and HCB. A notable finding in this study is that Chennai mothers have higher levels of HCHs in their milk and hence may transfer considerably higher amounts of the chemical than the mothers from all the other three places of the present study indicating a higher health risk to Chennai's children. It was also found that the levels of the two organochlorine pesticides (HCHs and DDTs) increased in Chermai mothers' milk in the last decade. Food items collected from Chennai markets did not show any remarkably higher levels of any of the chemicals measured in this study. Levels of the two classical organochlorines (DDTs and HCHs) have declined in many of the food items when compared with our data collected two decades before in the same locations, showing the effectiveness of the recent ban on both these chemicals in the country. The sources, possible health risks and the ways to curtail the effects of HCHs, especially at Chermai, should be investigated further. (c) 2007 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Takashi Kunito, Hisato Iwata, In Monirith, Chhoun Chamnan, Touch Seang Tana, Annamalai Subramanian, Shinsuke Tanabe
    CHEMOSPHERE 68 (3) 590 - 596 0045-6535 2007/06 [Peer-reviewed]
     Scientific journal 
    High concentration of mercury (Hg) in hair has been reported for Cambodians. To confirm the Hg contamination occurring through intake, Hg concentrations were determined in both hair and blood of residents (n = 20) from Phnom Penh, Cambodia. Mercury concentrations in the hair and blood were 0.69-190 mu g g(-1) dry wt and 5.2-58 mu g l(-1), respectively, which were lower than those from Hg contaminated or high fish intake regions, but were higher than those from non-contaminated regions. Some female subjects had hair and blood Hg levels exceeding the threshold values for neurotoxic effects. Interestingly, serum estrone and estradiol levels were positively correlated with blood Hg level for both males and females, indicating possible induction of female hormones by Hg exposure in Cambodians. (c) 2007 Elsevier Ltd. All rights reserved.
  • Kaori Onbe, Shin Nishida, Emi Sone, Naohisa Kanda, Mutsuo Goto, Luis A. Pastene, Shinsuke Tanabe, Hiroko Koike
    ZOOLOGICAL SCIENCE 24 (5) 449 - 464 0289-0003 2007/05 [Peer-reviewed]
     Scientific journal 
    The amino-acid sequences of the T-domain region of the Tbx4 gene, which is required for hindlimb development, are 100% identical in humans and mice. Cetaceans have lost most of their hindlimb structure, although hindlimb buds are present in very early cetacean embryos. To examine whether the Tbx4 gene has the same function in cetaceans as in other mammals, we analyzed Tbx4 sequences from cetaceans, dugong, artiodactyls and marine carnivores. A total of 39 primers were designed using human and dog Tbx4 nucleotide sequences. Exons 3, 4, 5, 6, 7, and 8 of the Tbx4 genes from cetaceans, artiodactyls, and marine carnivores were sequenced. Non-synonymous substitution sites were detected in the T-domain regions from some cetacean species, but were not detected in those from artiodactyls, the dugong, or the carnivores. The C-terminal regions contained a number of non-synonymous substitutions. Although some indels were present, they were in groups of three nucleotides and therefore did not cause frame shifts. The d(N)/d(S) values for the T-domain and C-terminal regions of the cetacean and artiodactylous Tbx4 genes were much lower than 1, indicating that the Tbx4 gene maintains it function in cetaceans, although full expression leading to hindlimb development is suppressed.
  • Nguyen Hung Minh, Tu Binh Minh, Hisato Iwata, Natsuko Kajiwara, Tatsuya Kunisue, Shin Takahashi, Pham Hung Viet, Bui Cach Tuyen, Shinsuke Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 52 (4) 458 - 465 0090-4341 2007/05 [Peer-reviewed]
     Scientific journal 
    Surficial sediment samples were collected from Hochiminh City canals, the Sai Gon-Dong Nai River, and its estuary, one of the most predominant industrial areas in Hochiminh City, southern Vietnam, for determination of selected persistent organic pollutants (POPs). Contamination pattern was as follows: PCBs >= DDTs > HCB > CHLs > HCHs. Concentrations of PCBs and DDTs ranged from 0.50-150 ng/g and 0.15-72 ng/g dry wt, respectively. On the other hand, concentrations of CHLs, HCHs, and HCB were mostly < 2 ng/g dry wt. Levels of the all organochlorines (OCs) in Hochiminh City canals were significantly higher than those in the other areas, indicating the urban areas as major pollution sources to the aquatic environment. The contamination pattern was PCBs > DDTs in the city canals but PCBs < DDTs in the downstream and the estuary, suggesting particularly high contamination by PCBs in the city. Examination of DDTs composition and their ratios demonstrated continuous input of this pesticide to the city canals. However, the combination of our data and those from available literature implies a decreasing trend of PCBs and DDTs in the environment. DDTs concentrations have been reduced 50% after approximately 5 years. Composition of CHLs in the sediment from Hochiminh City canals was comparable to those of common technical mixtures, suggesting continuous input of CHLs to the environment. CHLs might be in use for purposes like termite control, wood preservation, and protection of underground cables. Hazard assessment implies high toxic potential of DDTs for sediments from Hochiminh City canals and suggests the need for better management of municipal discharges.
  • Kaoru Azumi, Shinli Nakamura, Shin-Ichi Kitamura, Sung-Ju Jung, Keisuke Kanehira, Hisato Iwata, Shinsuke Tanabez, Satoru Suzuki
    FISHERIES SCIENCE 73 (2) 263 - 269 0919-9268 2007/04 [Peer-reviewed]
     Scientific journal 
    Recently, a serious disease spread extensively in aquaculture sites of the ascidian Halocynthia roretzi in Korea. To understand circumstances of ascidians in Korean aquaculture sites, residue levels of organotin compounds were analyzed, and detection of a marine birnavirus (MABV) in tissues of H. roretzi was attempted. Korean H. roretzi showed high concentrations of butyltins (mono, di, and tributyltins), especially in the gill, hepatopancreas, and digestive tract. However, there was no significant difference in the residues of butyltins in the hepatopancreas between diseased and non-diseased ascidians. The positive rate of MABV detection was high in the hepatopancreas, but also no significant difference was observed between diseased and non-diseased individuals. These observations suggest that an accumulation of tributyltin and a latency of MABV in H. roretzi tissues does not directly relate to the occurrence of the disease.
  • Nguyen Hung Minh, Tu Binh Minh, Natsuko Kajiwara, Tatsuya Kunisue, Hisato Iwata, Pham Hung Viet, Nguyen Phuc Cam Tu, Bui Cach Tuyen, Shinsuke Tanabe
    CHEMOSPHERE 67 (9) 1794 - 1801 0045-6535 2007/04 [Peer-reviewed]
     Scientific journal 
    The Mekong River delta is one of the largest agricultural land in the Southeast Asia. It plays a very important role for agriculture and fisheries in South Vietnam. However, comprehensive studies on the environmental pollution of persistent organic pollutants (POPs) in Mekong River delta have not been carried out in recent years. In this study, we collected sediment samples from the Mekong River to evaluate the contamination and ecological risks caused by several POP's. The contamination pattern of POPs was DDT > PCBs > CHLs > HCHs > HCB. DDTs are the most abundant pollutants, their concentration ranging from 0.01 to 110 ng/g dry wt, followed by PCBs (0.039-9.2 ng/g dry wt). DDTs and PCBs concentrations were higher in sediment from adjacent to urban areas than those from rural and agricultural sites, suggesting urban areas as important point sources of DDTs and PCBs to the river. Ratio of pp'-DDT/p,p'-DDE was lower compared to those previously reported. However, some samples still had the ratio higher than 0.5, indicating recent input of DDT into the aquatic environments. This result shows that although the magnitude of contamination decreased over time, recent inputs of DDTs to the river still occur. Some sediment samples had concentrations of DDT compounds higher than the standards from the Canadian Environmental Quality Guideline, suggesting continuous monitoring for POPs contamination in the Mekong River is necessary. (c) 2006 Elsevier Ltd. All rights reserved.
  • Jin-Seon Lee, Eun-Young Kim, Hisato Iwata, Shinsuke Tanabe
    COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY 145 (3) 379 - 393 1532-0456 2007/04 [Peer-reviewed]
     Scientific journal 
    High levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related planar halogenated aromatic hydrocarbons (PHAHs) are accumulated in fish-eating birds including common cormorant (Phalacrocorax carbo). Most of the biochemical and toxic effects of TCDD are mediated by a basic helix-loop-helix and a conserved region among Per, ARNT, and Sim (bHLH/PAS) proteins, aryl hydrocarbon receptor (AHR) and AHR nuclear translocator (ARNT). To study the molecular mechanism of TCDD toxicity in common cormorant as an avian model species, characterization of the AHR/ARNT signaling pathway in this species is necessary. The present study focuses on molecular characterization of ARNT from common cormorant (ccARNT). The cDNA of the ccARNT isoform, ccARNT1 obtained by the screening of hepatic cDNA library contains a 2424-bp open reading frame that encodes 807 amino acids, exhibiting high identities (92%) with chicken ARNT. This isoform contains a unique 22 amino acid residue in 3' end of PAS A domain as is also recognized in chicken ARNT. The ccARNT2 cDNA isolated from brain tissue has a 2424-bp open reading frame. The deduced amino acid sequence of ccARNT2 protein (716 aa) shows a conservation of bHLH and PAS motif in its N-terminal region with high similarities (96% and 78%, respectively) to that of ccARNT1. Using quantitative RT-PCR methods, the tissue distribution profiles of ccARNT1 and ccARNT2 were unveiled. Both ccARNT1 and ccARNT2 mRNAs were ubiquitously expressed in all examined tissues including liver. The expression profile of ccARNT1 was comparable with that of rodent ARNT1, but ccARNT2 was not with rodent ARNT2, implying different roles of ARNT2 between the two species. There was a significant positive correlation between ARNT1 and ARNT2 mRNA expression levels in the liver of wild cormorant population, indicating that their expressions may be enforced by similar transcriptional regulation mechanism. Novel variants of ccARNT1 and ccARNT2 isoforms that were supposed to arise from their splicing process were also identified and their hepatic expression profiles were determined. These results indicate that ccARNT1, ccARNT2 and their splice variants may more intricately regulate the AHR/ARNT signaling pathway and consequently may be responsible for the species diversity of toxic effects and susceptibility to PHAHs. (c) 2007 Elsevier Inc. All rights reserved.
  • Dong-Ha Nam, Eun-Young Kim, Hisato Iwata, Shinsuke Tanabe
    COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY 145 (3) 295 - 305 1532-0456 2007/04 [Peer-reviewed]
     Scientific journal 
    To characterize avian MTs, MT cDNAs were cloned from liver of cormorant (Phalacrocorax carbo) and mallard (Anas platyrhynchos). Expression profiles of NIT isoforms and relationships between metal accumulation and MT mRNA expression in tissues were also investigated. We succeeded in cDNA cloning of MT1/2 from cormorant and MT1 in mallard. DNA sequence of chicken MT1 was obtained from chicken (Gallus gallus) genomic database. Considering previous reports on avian MTs, birds possess at least two distinct MT isoforms. Comparison of genomic synteny among vertebrates and phylogenetic analysis of MT amino acid sequences revealed that avian MT 1/2 are evolutionarily close to mammalian MT3. Messenger RNAs of both MT isoforms were detected in all the tissues/organs in cormorant and mallard. Liver was the primary organ for cormorant MT1/2, and mallard MT2, whereas MT1 was dominant in mallard heart. Interspecies comparison of tissue distribution of MT mRNA expression between cormorant and mallard indicated that MT2 profile was similar, but MT1 was not. Significant positive correlations of mRNA expression levels between MT1 and MT2 were observed in the liver and kidney of cormorants, whereas no correlation was found in mallards. Expression levels of cormorant MT1/2 showed significant positive correlations with hepatic Cu and Zn concentrations, suggesting that both MT isoforms were induced by Cu and Zn in livers. Cormorant MT2 expression level exhibited a significant positive correlation with hepatic Ag, and a negative correlation with Rb, indicating that Ag and Rb concentrations depend on the expression of MT2 by Cu and Zn. In mallard, MT1 had no correlation with any metal concentration, and MT2 expression was positively correlated only with Cu, even though hepatic Cu and Zn concentrations in mallard were much higher than in cormorant. This may indicate that cormorant is a more susceptible species than mallard in terms of MT induction. These findings suggest tissue-, species-, and MT isoform-specific responses to metal stresses in these aquatic birds. (c) 2007 Elsevier Inc. All tights reserved.
  • Haruhiko Nakata, Hiroshi Sasaki, Akira Takemura, Motoi Yoshioka, Shinsuke Tanabe, Kurunthachalam Kannan
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 41 (7) 2216 - 2222 0013-936X 2007/04 [Peer-reviewed]
     Scientific journal 
    Bioaccumulation of synthetic musks in a marine food chain was investigated by analyzing marine organisms at various trophic levels, including lugworm, clam, crustacean, fish, marine mammal, and bird samples collected from tidal flat and shallow water areas of the Ariake Sea, Japan. Two of the polycyclic musks, HHCB and AHTN, were the dominant compounds found in most of the samples analyzed, whereas nitro musks were not detected in any of the organisms, suggesting greater usage of polycyclic musks relative to the nitro musks in Japan. The highest concentrations of HHCB were detected in clams (258-2730 ng/g lipid wt.), whereas HHCB concentrations in mallard and black-headed gull were low, and comparable with concentrations in fish and crab. These results are in contrast to the bioaccumulation pattern of polychlorinated biphenyls; for which a positive correlation between the concentration and the trophic status of organisms was found. Such a difference in the bioaccumulation is probably due to the metabolism and elimination of HHCB in higher trophic organisms. Temporal trends in concentrations of synthetic musks were examined by analyzing tissues of marine mammals from Japanese coastal waters collected during 1977-2005. HHCB concentrations in marine mammals have shown significant increase since the early 1990s, suggesting a continuous input of this compound into the marine environment. Comparison of the time trend for HHCB with those for PCBs and PBDEs suggested that the rates of increase in HHCB concentrations were higher than the other classes of pollutants. To examine the geographical distribution of HHCB, we have analyzed tissues of fish, marine mammals, and birds collected from several locations. Synthetic musks were not detected in a sperm whale (pelagic species) from Japanese coastal water and in eggs of south polar skua from Antarctica. While the number of samples analyzed is limited, these results imply a lack of long-range transportation potential of synthetic musks in the environment.
  • Oyuna V. Tsydenova, Agus Sudaryanto, Natsuko Kajiwara, Tatsuya Kunisue, Valeriy B. Batoev, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 146 (1) 225 - 232 0269-7491 2007/03 [Peer-reviewed]
     Scientific journal 
    Human breast milk samples collected during 2003/04 in Buryatia, a Russian autonomous republic, were analyzed in order to assess human exposure to organohalogen compounds including organochlorine pesticides, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). When compared with available worldwide data, levels of HCB (23-880 ng/g lipid wt.), PCBs (69-680 ng/g lipid wt.), and HCHs (100-3700 ng/g lipid wt.) were relatively high, indicating elevated human exposure to these organochlorines (OCs) in Buryatia. In contrast to OCs. PBDE concentrations were low (0.46-1.7 ng/g lipid wt.). Out of 14 BDE congeners analyzed, BDE-28, BDE-47, BDE-100, BDE153, BDE-197, and BDE-207 were detected. Estimated daily intakes (EDIs) of HCHs, HCB, CHLs, and PCBs by infants solely from human milk for 100%, 43%, 34%, and 17% of the samples, respectively, exceeded guideline thresholds. Although high EDIs raise concern for possible toxic effects of OCs, women in Buryatia are recommended to breastfeed due to numerous advantages of breastfeeding for mother and child. (c) 2006 Elsevier Ltd. All rights reserved.
  • Tetsuro Agusa, Takashi Kunito, Agus Sudaryanto, In Monirith, Supawat Kan-Atireklap, Hisato Iwata, Ahmad Ismail, Joompol Sanguansin, Muswerry Muchtar, Touch Seang Tana, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 145 (3) 766 - 777 0269-7491 2007/02 [Peer-reviewed]
     Scientific journal 
    Concentrations of 20 trace elements were determined in muscle and liver of 34 species of marine fish collected from coastal areas of Cambodia, Indonesia, Malaysia and Thailand. Large regional difference was observed in the levels of trace elements in liver of one fish family (Carangidae): the highest mean concentration was observed in fish from the Malaysian coastal waters for V, Cr, Zn, Pb and Bi and those from the Java Sea side of Indonesia for Sn and Hg. To assess the health risk to the Southeast Asian populations from consumption of fish, intake rates of trace elements were estimated. Some marine fish showed Hg levels higher than the guideline values by U.S. Environmental Protection Agency and Joint FAO/WHO Expert Committee on Food Additives (JECFA). This suggests that consumption of these fish may be hazardous to the people. (c) 2006 Elsevier Ltd. All rights reserved.
  • Jerzy Falandysz, Takashi Kunito, Reiji Kubota, Leszek Bielawski, Aneta Mazur, Jaromir J. Falandysz, Shinsuke Tanabe
    JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 42 (14) 2081 - 2088 1093-4529 2007 [Peer-reviewed]
     Scientific journal 
    A survey of 26 metallic elements and metalloids such as Ag, Al, Ba, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Sb, Se, Sr, Tl, V and Zn was carried out using ICP-MS, ICP- OES, HG-AAS and CV-AAS in the caps and stalks of edible mushroom Brown Birch Scaber Stalk collected from two lowland and one mountain sites in Poland. Ag, Al, Cd, Cr, Cs, Cu, Fe, Hg, K, Mg, Mo, Pb, Rb, Se, V and Zn occurred in greater concentration in the caps than stalks of Brown Birch Scaber Stalk, and opposite situation was for Tl and Na. Brown Birch Scaber Stalk collected from the site in Sudety Mountains did contain Al, Ba, Cs, Fe, Ga, Ni, Pb, Sr and V in significantly greater concentration when compared to specimens collected from the lowland sites, and what imply on significance of geological origin and/or soil substrate pollution impacting on mineral composition of this mushroom species. The results provide useful environmental and nutritional baseline level information on mineral composition of Brown Birch Scaber Stalk from unpolluted sites.
  • J. Falandysz, T. Kunito, R. Kubota, K. Lipka, A. Mazur, Justyna J. Falandysz, S. Tanabe
    JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 42 (11) 1615 - 1623 1093-4529 2007 [Peer-reviewed]
     Scientific journal 
    Concentrations of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Cs, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Pb, Rb, Se, Sb, Sr, V, Tl and Zn have been determined in the whole fruiting bodies, as well as separately in caps and stalks, of fly agaric collected from three geographically distant sites in northern part of Poland. The elements were determined using ICP-MS, ICP-OES, HG-AAS and CV-AAS, respectively. For elements such as Al, Ba, Cr, Fe, Ga, Mo, Mn, Pb, Sb, Sr, Tl, and V concentrations were similar in the caps and stalks, respectively, and for K, Zn, Ag, Ca, Cd, Cu, Hg, Mg, Rb and Se were greater in the caps, while for Co, Cs and Na in the stalks. For Ag, Al, Ba, Ca, Cd, Co, Cr, Cs, Fe, Ga, Hg, Mn, Mo, Pb, Rb, Sb, Sr, Tl and V concentration in the caps showed spatial variations (P < 0.05), while for Cu, K, Mg, Na, Se and Zn was independent of the site. The elements such as K with median or mean in the caps between 37,000 and 43,000 mu g/g .dm and Mg with 920 and 1,100 mu g/g dm were most abundant. Next, within median values range from approximately 100 to 500 mu g/g dm were such as Ca, Fe and Al, and in descending order they followed by Rb (100-400 mu g/g dm); V, Na, Zn ( 50-200 mu g/g dm); Cu, Mn (10-50 mu g/g dm); Cd (10-20 mu g/g dm); Se (5 mu g/g dm); Ba (< 1-3); Cr, Ag, Pb, Sr (< 1-2 mu g/g dm); Cs, Co, Hg (< 1 - 1 mu g/g dm); Ga (< 0.5), Sb, Mo and Tl (< 0.1 mu g/g dm).
  • J. Falandysz, T. Kunito, R. Kubota, A. Brzostowski, Mazur A. Justyna, J. Falandysz, S. Tanabe
    JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 42 (8) 1161 - 1168 1093-4529 2007 [Peer-reviewed]
     Scientific journal 
    Concentrations of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Cs, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Se, Sb, Sr, V, Tl and Zn have been determined in the whole fruiting bodies as well as separately in caps and stalks of Poison Pax collected from three geographically distant sites across Poland. The elements were determined using ICP- MS, ICP- OES, HG- AAS and CV- AAS, respectively. Based on arithmetic mean and median values for Poison Pax specimens from the Lezno site the elements such as Ag, Co, Cr, Cs, Mn, Mo, K, Pb, Rb, Sb, Se, V and Tl occur at similar concentration both in the caps and stalks, while for Cd, Cu, Hg, Mg and Zn around two- fold greater concentrations were noted in caps than stalks ( cap/ stalk concentration quotient > 1). Cs, Cd, Ni and Rb occurred at much greater concentration in specimens collected from the Klodzka Hollow in the Sudety Mountains when compared to the lowland site ( Mann - Whitney U- test), and slightly greater values were noted also for Cr, Mo and Rb, while for Ca, Co, Mg and Mn were smaller The results provide useful environmental and biological baseline level of information for metallic elements of Poison Pax.
  • Agusa, T, Kubota, R, Kunito, T, Minh, T. B, Trang, P. T. K, Chamnan, C, Iwata, H, Viet, P. H, Tana, T. S, Tanabe, S
    Biomedical Research on Trace Elements 18 (1) 35 - 47 2007 [Peer-reviewed]
  • Kwadwo Ansong Asante, Tetsuro Agusa, Annamalal Subramanian, Osmund D. Ansa-Asare, Charles A. Biney, Shinsuke Tanabe
    CHEMOSPHERE 66 (8) 1513 - 1522 0045-6535 2007/01 [Peer-reviewed]
     Scientific journal 
    This study was conducted to assess the contamination status of 22 trace elements, especially As in water and residents in Tarkwa, a historic mining town in Ghana. Drinking water and human urine samples were collected from Tarkwa in addition to control samples taken from Accra, the capital of Ghana in March, 2004. Concentrations of As and Mn in some drinking water samples from Tarkwa were found above the WHO drinking water guidelines posing a potential health risk for the people. A potential health risk of As and Mn is a concern for the people consuming the contaminated water in this area. No significant difference of As concentrations in human urine between mining town (Tarkwa) and control site (Accra) was observed. Although As concentrations in drinking water in Tarkwa were low, urinary As levels were comparable to those reported in highly As-affected areas in the world. These results suggest the presence of other sources of As contamination in Ghana. This is the first study oil multi-elemental contamination in drinking water and human from a mining town in Ghana. (c) 2006 Elsevier Ltd. All rights reserved.
  • Tatsuya Kunisue, Nozonu Takayanagi, Toshio Tsubota, Shinsuke Tanabe
    CHEMOSPHERE 66 (2) 203 - 211 0045-6535 2007/01 [Peer-reviewed]
     Scientific journal 
    The present study determined the accumulation features of persistent organochlorines (OCs) such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), and chlordane compounds (CHLs) in wild raccoon dogs (RDs; Nyclereutes procyonoides) collected from Kanagawa prefecture in Japan during 2001. In livers of RDs, CHLs were remarkably dominant (20 times higher than PCBs) followed by PCBs > DDTs > HCHs > HCB, whereas the chemicals in muscles were in the order of CHLs > PCBs > HCHs > DDTs > HCB. The accumulation pattern of OCs in RDs was different from those in Japanese humans and avian species reported previously, which generally accumulate higher levels of DDTs and PCBs than CHLs. This result indicates that RDs have been exposed to relatively high levels of CHLs and have high metabolic and elimination capacity for DDTs. In fact, CHL levels in RDs were higher than those in humans and some avian species, while DDT levels in RDs were much lower than other animals. In particular, extremely high accumulation levels of oxychlordane, which is a metabolite from chlordanes and nonachlors, were observed in RD livers. The higher toxic potency of oxychlordane than parent compounds may suggest that RDs are at high risk by this metabolite. On lipid weight basis, PCBs, HCHs and HCB levels were almost similar in livers and Muscles, suggesting that the tissue distribution of these compounds principally followed the lipid-dependent accumulation. However, accumulation levels of oxychlordane and p,p'-DDD in livers were significantly higher than those in muscles, and concentration ratios of liver to muscle (L/M ratios) of these Compounds were greater than 1.0 in all the specimens. This phenomenon was similar to PCDD/DF congener accumulation patterns observed previously in RDs. When relationships between hepatic TEQs and L/M ratios were examined for oxychlordane and p,p'-DDD, L/M ratios for these compounds significantly increased with hepatic TEQ levels, suggesting their hepatic sequestration in TEQs-dependent manner.
  • Lin Tao, Kurunthachalam Kannan, Natsuko Kajiwara, Monica M. Costa, Gilberto Fillmann, Shin Takahashi, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 40 (24) 7642 - 7648 0013-936X 2006/12 [Peer-reviewed]
     Scientific journal 
    Perfluorinated chemicals (PFCs) have been used as surfactants in industrial and commercial products for over 50 years. Earlier studies of the geographical distribution of PFCs focused primarily on the Northern Hemisphere, while little attention was paid to the Southern Hemisphere. In this study, livers from eight species of albatrosses, blood from elephant seal, and blood and eggs from penguins and polar skua collected from the Southern Ocean and the Antarctic during 1995 - 2005 were analyzed for 10 PFCs. In addition, for comparison with the Southern Ocean samples, we analyzed liver, sera, and eggs from two species of albatrosses from Midway Atoll in the North Pacific Ocean. Perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) were found in livers of albatrosses from the Southern Ocean. PFOS was the major contaminant, although the concentrations were < 5 ng/g, wet wt, in 92% of the albatross livers analyzed. PFOA was detected in 30% of the albatross livers, with a concentration range of < 0.6 - 2.45 ng/g, wet wt. Other PFCs, including long-chain perfluorocarboxylates (PFCAs), were below the limits of quantitation in livers of albatrosses from the Southern Ocean. In liver, sera, and eggs of albatrosses from the North Pacific Ocean, long-chain PFCAs (perfluorononanoate, perfluorodecanoate, perfluoroundecanoate, and perfluorododecanoate) were found at concentrations similar to those of PFOS and PFOA. The mean concentration of PFOS in livers of Laysan albatrosses from the North Pacific Ocean (5.1 ng/g, wet wt) was higher than that in several species of albatrosses from the Southern Ocean (2.2 ng/g, wet wt). Species-specific differences in the concentrations of PFOS were noted among Southern Ocean albatrosses, whereas geographical differences in PFOS concentrations among the Indian Ocean, South Pacific Ocean, and South Atlantic Ocean were insignificant. Concentrations of PFOS and PFOA were, respectively, 2- and 17-fold higher in liver than in sera of Laysan albatrosses. PFOS was found in the blood of elephant seals from Antarctica at concentrations ranging from < 0.08 to 3.52 ng/mL. PFOS was found in eggs (2.1 - 3.1 ng/g) and blood (< 0.24 - 1.4 ng/mL) of polar skuas but was not detected in penguins from Antarctica. Our study documents the existence of low but detectable levels of PFOS and PFOA in Southern Hemisphere fauna, suggesting distribution of these compounds on a global scale.
  • Karri Ramu, Natsuko Kajiwara, Hiroko Mochizuki, Hitoshi Miyasaka, Kwadwo Ansong Asante, Shin Takahashi, Suguru Ota, Hsin-Ming Yeh, Shuhei Nishida, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 52 (12) 1827 - 1832 0025-326X 2006/12 [Peer-reviewed]
     Scientific journal
  • Kurunthachalam Kannan, Tetsuro Agusa, Emily Perrotta, Nancy J. Thomas, Shinsuke Tanabe
    CHEMOSPHERE 65 (11) 2160 - 2167 0045-6535 2006/12 [Peer-reviewed]
     Scientific journal 
    Infectious diseases have been implicated as a cause of high rates of adult mortality in southern sea otters. Exposure to environmental contaminants can compromise the immuno-competence of animals, predisposing them to infectious diseases. In addition to organic pollutants, certain trace elements can modulate the immune system in marine mammals. Nevertheless, reports of occurrence of trace elements, including toxic heavy metals, in sea otters are not available. In this study, concentrations of 20 trace elements (V, Cr, Mn, Co, Cu, Zn, Rb, Sr, Mo, Ag, Cd, In, Sri, Sb, Cs, Ba, Hg, Tl, Pb, and Bi) were measured in livers of southern sea otters found dead along the central California coast (n = 80) from 1992 to 2002. Hepatic concentrations of trace elements were compared among sea otters that died from infectious diseases (n = 27), those that died from non-infectious causes (n = 26), and otters that died in emaciated condition with no evidence of another cause of death (n = 27). Concentrations of essential elements in sea otters varied within an order of magnitude, whereas concentrations of non-essential elements varied by two to five orders of magnitude. Hepatic concentrations of Cu and Cd were 10- to 100-fold higher in the sea otters in this study than concentrations reported for any other marine mammal species. Concentrations of Mn, Co, Zn, and Cd were elevated in the diseased and emaciated sea otters relative to the non-diseased sea otters. Elevated concentrations of essential elements such as Mn, Zn, and Co in the diseased/emaciated sea otters suggest that induction of synthesis of metallothionein and superoxide dismutase (SOD) enzyme is occurring in these animals, as a means of protecting the cells from oxidative stress-related injuries. Trace element profiles in diseased and emaciated sea otters suggest that oxidative stress mediates the perturbation of essential-element concentrations. Elevated concentrations of toxic metals such as Cd, in addition to several other organic pollutants, may contribute to oxidative stress-meditated effects in sea otters. (c) 2006 Elsevier Ltd. All rights reserved.
  • Tatsuya Kunisue, Shigeyuki Nakanishi, Nariko Oka, Fumio Sato, Miyako Tsurmi, Shinsuke Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 40 (22) 6919 - 6927 0013-936X 2006/11 [Peer-reviewed]
     Scientific journal 
    Concentrations of dioxins and related compounds (DRCs), such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs), were determined in eggs, nestlings, and adults of black-footed albatross (BfA; Diomedea nigripes) and short- tailed albatross (StA; Diomedea albatrus) collected from the Torishima Island in Japan during 2002, which is one of their breeding grounds. Observed DRC concentrations, especially PCDFs and non-ortho Co-PCBs, in eggs of BfA and StA were relatively higher than those in other oceanic, coastal, and inland wild birds reported recently and were comparable to those in a pooled BfA egg from Midway Atoll in 1993, implying continuous input of these contaminants into open ocean and possible albatross- specific exposure. Concentrations of PCDDs except 12378-P5CDD and high-chlorinated PCDFs in 3-month-old BfA nestling were lower than those in 1-month-old nestling, indicating their developmental dilution. On the other hand, higher levels of T-4-H(6)CDFs and Co-PCBs, especially low-chlorinated congeners such as 2378-T4CDF and T(4)CB77, were found in 3-month-old BfA nestling, suggesting specific exposure to these contaminants, possibly due to their higher transportability than high-chlorinated congeners. Estimated biomagnification factors of almost all the congeners in adults were apparently greater than those in nestlings, except 2378-T4CDF, T(4)CB77, and H-7-O8CDD/Fs. This could be due to preferential metabolism of 2378-T4CDF and T(4)CB77 and lower uptake efficiency of high-chlorinated congeners through the gastrointestinal tract in adults. Toxic equivalents in BfA and StA eggs estimated using WHO-avian toxic equivalency factors exceeded some toxicity thresholds for avian embryos, indicating possible adverse effects of DRCs to albatross embryos.
  • Masanobu Yamauchi, Eun-Young Kim, Hisato Iwata, Yasuhiro Shima, Shinsuke Tanabe
    AQUATIC TOXICOLOGY 80 (2) 166 - 179 0166-445X 2006/11 [Peer-reviewed]
     Scientific journal 
    The toxicity of dioxins such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is mainly mediated by the aryl hydrocarbon receptor (AHR), which regulates the multiple target genes including cytochrome P4501A (CYP1A). In general, bony fishes, which possess at least two distinct AHRs are one of the most sensitive vertebrates to TCDD in early life stage. However, the physiological and toxicological roles of piscine multiple AHRs are not fully understood, especially in marine fish. To understand which AHR is responsible for TCDD toxicity in a marine fish species, we characterized the early life stage toxicity related to the expression of AHRs and CYP1A in red seabream (Pagrus major). The embryos at 10 h post-fertilization (hpf) were treated with 0-100 mu g/L TCDD for 80 min waterborne exposure. TCDD dose-dependently elicited developmental toxicities including mortality, yolk sac edema, retarded body growth, spinal deformity, reduced heart rate, shortened snout, underdeveloped fin, heart, and lower jaw. Intriguingly, hemorrage and pericardium edema, typical TCDD developmental defects noticed in other fish species, were not found in red seabream until test termination. The ECegg 50s for yolk sac edema, underdeveloped fin, and spinal deformity were 170, 240, and 340 pg/g, respectively. The LC(egg)50 was 360pg/g embryo, indicating that this species is one of the most sensitive fishes to TCDD toxicity. The expression levels of rsAHR1, rsAHR2 and CYP1A mRNAs were also determined in different developmental stages. The rsAHR2 mRNA expression dose-dependently increased following TCDD exposure, while rsAHR1 mRNA level was not altered. Level of rsAHR2 mRNA measured by two-step real-time PCR was 30 times higher than rsAHR1 in embryos treated with the highest dose. Temporal patterns of rsAHR2 and CYP1A mRNAs were similar in TCDD-treated embryos, representing a significant positive correlation between rsAHR2 and CYP1A mRNA levels, but not between rsAHR1 and CYP1A. In comparison of temporal trends of TCDD-induced AHRs and CYP1A expression, and developmental toxicities, the highest expression of rsAHR2 and CYP1A mRNA were detected prior to the appearance of maximal incidence of TCDD toxic manifestations. These results suggest that rsAHR2 may be dominantly involved in the transcriptional regulation of CYP1A, and several TCDD defects are dependent on the alteration of rsAHR2 and/or rsAHR2-CYP1A signaling pathway that is controlled through their expression levels. (c) 2006 Published by Elsevier B.V.
  • Hiroki Sakai, Hisato Iwata, Eun-Young Kim, Oyuna Tsydenova, Nobuyuki Miyazaki, Evgeny A. Petrov, Valeriy B. Batoev, Shinsuke Tanabe
    TOXICOLOGICAL SCIENCES 94 (1) 57 - 70 1096-6080 2006/11 [Peer-reviewed]
     Scientific journal 
    To characterize the function of constitutive active/androstane receptor (CAR) in aquatic mammals, CAR complementary DNA (cDNA) was cloned from the liver of Baikal seal (Pusa sibirica) from Lake Baikal, Russia, and the messenger RNA (mRNA) expression levels in various tissues/organs of the wild population and the CAR ligand profiles were investigated. The seal CAR cDNA had an open reading frame of 1047 bp encoding 348 amino acids that revealed 74-84% amino acid identities with CARs from rodents and human. The mRNA expression profile of tissues/organs represented that Baikal seal CAR was predominantly expressed in the liver followed by heart and intestine. The expression analysis of hepatic CAR mRNA showed no correlation with expression of cytochrome P450 (CYP) 1A, 1B, 2B, 2C, and 3A-like proteins, indicating that the CAR expression level may not be the sole determinant of the regulation of these CYP expressions in the seal liver. There was no significant correlation between CAR expression and any of the persistent organic pollutants (POPs) levels. Furthermore, we performed an in vitro CAR transactivation assay using MCF-7 cells transfected with Baikal seal CAR expression plasmid and (NR1)(3)-luciferase reporter gene plasmid. In the transactivation analysis of Baikal seal CAR, neither repression by androstanol and androstenol, nor activation by estrone and estradiol, which are recognized as endogenous ligands for mouse and human CARs, was detected. On the other hand, bile acids such as chenodeoxycholic acid, deoxycholic acid, and lithocholic acid activated the seal CAR as well as mouse CAR. As for exogenous chemicals, the seal CAR was transactivated by a human CAR agonist, 6-(4-chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehyde O-(3,4-dichlorobenzyl)oxime), but not by a mouse CAR agonist, (1,4-bis[2-(3,5-dichloropyridyloxy)]benzene). In addition, the seal CAR was also activated by polychlorinated biphenyls (PCBs) (Kanechlor-500, International Union of Pure and Applied Chemistry No. PCB153; 2,2',4,4',5,5'-hexachlorobiphenyl and PCB180; 2,2',3,4,4',5,5'-heptachlorobiphenyl), and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p'-DDT) and its metabolite, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE). The seal CAR responded more sensitively to PCBs than the mouse CAR. Based on the results of CAR transactivation assay, the lowest observable effect levels of Kanechlor-500, PCB153, PCB180, p,p'-DDT, and p,p'-DDE in Baikal seal were estimated to be 10, 20, 20, 10, and 10 ppm on wet weight basis, respectively. These results suggest that CAR is conserved in diverse mammalian species including seals. Whereas the seal CAR-mediated gene transcription may potentially be a sensitive response to the exposure of certain POPs, the ligand profile of seal CAR may be different from those of other mammalian CARs. This study indicates that CAR-mediated responses may be useful information to assess the ecotoxicological risk of xenobiotics such as POPs in wildlife but the previous results derived from rodent and human CAR may not be applicable to the risk assessment in wild species.
  • Karri Ramu, Natsuko Kajiwara, Paul K. S. Lam, Thomas A. Jefferson, Kaiya Zhou, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 144 (2) 516 - 523 0269-7491 2006/11 [Peer-reviewed]
     Scientific journal 
    Polybrominated diphenyl ethers (PBDEs) and organochlorine compounds (OCs) were determined in the blubber of male finless porpoises (Neophocaena phocaenoides) collected in 1990 and 2000/01 from the South China Sea. Among the organohalogen compounds analyzed, DDTs and PCBs were the predominant contaminants in the porpoises, ranging from 26,000 to 260,000 and 1400 to 28,000 ng/g lipid wt., respectively. PBDEs ranged from a minimum of 84 ng/g lipid wt., in 1990 to a maximum of 980 ng/g lipid wt., in 2001, showing a significant increase during the time period investigated. Congener profiles in finless porpoises did not shift to higher BDE congeners during these years, implying a continuous discharge of lower BDE commercial mixtures, such as PentaBDE. For OCs, HCHs concentrations decreased significantly, while others did not exhibit any significant temporal variation. Biomagnification factors (BMFs) were found to be highest for CHLs and lowest for HCB. PBDEs and PCBs had comparable BMFs, indicating a similar potential for biomagnification through the food web. (c) 2006 Elsevier Ltd. All rights reserved.
  • Daisuke Ueno, Mehran Alaee, Chris Marvin, Derek C. G. Muir, Gordia Macinnis, Eric Reiner, Patrick Crozier, Vasile I. Furdui, Annamalai Subramanian, Gilberto Fillmann, Paul K. S. Lam, Gene J. Zheng, Muswerry Muchtar, Hamidah Razak, Maricar Prudente, Kyu-hyuck Chung, Shinsuke Tanabe
    ENVIRONMENTAL POLLUTION 144 (1) 238 - 247 0269-7491 2006/11 [Peer-reviewed]
     Scientific journal 
    The geographical distribution of hexabromocyclododecane (HBCD) was investigated through analysis of muscle tissue of skipjack tuna (Katsuwonus pelamis) collected from offshore waters of Asia-Pacific region (Japan, Taiwan, Philippines, Indonesia, Seychelles, Brazil, Japan Sea, East China Sea, South China Sea, Indian Ocean and North Pacific Ocean). HBCD was detected in almost all samples analyzed (< 0.1 to 45 ng/g lipid weight basis), indicating widespread presence of this compound in the marine environment. Elevated concentrations of HBCD were found in skipjack tuna from areas around Japan, which have the larger modem industrial/urban societies, and implicated these areas as primary regional sources. All three individual HBCD isomers (alpha-, gamma- and beta-HBCD) were detected in almost all samples; the percentage contribution of the alpha-isomer to total HBCD increased with increasing latitude. The estimated empirical 1/2 distance for alpha-HBCD was 8500 km, which is one of the highest atmospheric transportability among various halogenated persistent organic pollutants (POPs). (c) 2006 Elsevier Ltd. All rights reserved.
  • Minh, N. H, Minh, T. B, Kajiwara, N, Kunisue, T, Iwata, H., Viet, P. H., Tu, N. P. C, Tuyen, B. C, Tanabe, S
    Environmental Toxicology and Chemistry 25 (10) 2700 - 2709 2006/10 [Peer-reviewed]
  • Natsuko Kajiwara, Tatsuya Kunisue, Satoko Kamikawa, Yoko Ochi, Shinichi Yano, Shinsuke Tanabe
    MARINE POLLUTION BULLETIN 52 (9) 1066 - 1076 0025-326X 2006/09 [Peer-reviewed]
     Scientific journal 
    Blubber and liver samples were obtained for analysis of wide ranges of contaminants from killer whales (Orcinus orca) which were locked away in drifting sea ice on the coast of Rausu, the Shiretoko Peninsula in Eastern Hokkaido, Japan in February 2005. Among the organolialogen compounds analyzed, DDTs were the predominant contaminants with concentrations ranging from 28 to 220 mu g/g on a lipid-weight basis followed by PCBs and other organochlorine pesticides. PBDEs levels were two or three orders of magnitude lower than those of PCBs and DDTs. 2,3,7,8-Tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) derived by WHO mammal-TEF in killer whales were in the range of 110-440 pgTEQ/g. Mono-ortho coplanar PCBs contributed to 75-98% of total TEQs, indicating coplanar PCBs are significant contaminants for risk assessment in this species. The fact that hepatic residue levels of butyltins (from 13 to 770 ng/g wet weight) were much higher than those of phenyltins may be reflecting extensive use of tributyltin as antifouling paint. (c) 2006 Elsevier Ltd. All rights reserved.
  • Akira Kubota, Hisato Iwata, Heather M. H. Goldstone, Eun-Young Kim, John J. Stegeman, Shinsuke Tanabe
    TOXICOLOGICAL SCIENCES 92 (2) 394 - 408 1096-6080 2006/08 [Peer-reviewed]
     Scientific journal 
    The present study characterized cytochrome P4501A (CYP1A) isoforms from common cormorant (Phalacrocorax carbo) with regard to their evolutionary relationships and their roles in disposition of dioxin and related compounds (DRCs). Two clones isolated from a cormorant liver cDNA library were named CYP1A4 and CYP1A5 on the basis of greatest overall amino acid identity shared with chicken (Gallus gallus) CYP1A4 (78%) and CYP1A5 (78%), respectively. Spatial heterogeneity in phylogenetic signal along the sequences strongly indicated that cormorant CYP1A4 and CYP1A5 have undergone partial interparalog gene conversion, similar to chicken and mammalian CYP1As. Phylogenetic analysis of a putatively unconverted region produced a tree topology consistent with the orthology of avian CYP1A5s with mammalian CYP1A2s and avian CYP1A4s with mammalian CYP1A1s. Hepatic CYP1A4 and CYP1A5 mRNA levels in wild cormorants from Lake Biwa, Japan, were quantified to examine the effects of DRCs on isoform-specific expression and to evaluate the toxicokinetics of DRCs in which CYP1A expression is involved. Both CYP1A4 and CYP1A5 mRNA levels were positively correlated with total tetrachlorodibenzo-p-dioxin toxic equivalents and concentrations of each congener in most cases in the liver, suggesting the induction of both enzymes through a shared transcriptional mechanism. The lack of correlation of 2,3,7,8-tetrachlorodibenzofuran and 3,3',4,4'-tetrachlorobiphenyl (PCB77) to CYP1A gene expression is likely due to the rapid metabolism of these two congeners. Liver-to-muscle concentration ratios for most DRC congeners except PCB77 and mono-ortho coplanar polychlorinated biphenyls significantly increased with an elevation of CYP1A4 and CYP1A5 mRNA levels. The present data suggest that hepatic sequestration of some DRCs occurs in cormorant via binding to either CYP1A5 or both CYP1A4 and CYP1A5.
  • Tatsuya Kunisue, Masayoshi Muraoka, Masako Ohtake, Agus Sudaryanto, Nguyen Hung Minh, Daisuke Ueno, Yumi Higaki, Miyuki Ochi, Oyuna Tsydenova, Satoko Kamikawa, Tomoyuki Tonegi, Yumi Nakamura, Hiroshi Shimomura, Junya Nagayama, Shinsuke Tanabe
    CHEMOSPHERE 64 (9) 1601 - 1608 0045-6535 2006/08 [Peer-reviewed]
     Scientific journal 
    Contamination levels of persistent organochlorines (OCs) such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), and chlordane compounds (CHLs) was examined in human breast milk collected during 2001-2004 from Fukuoka prefecture in Japan. The concentrations of OCs such as dioxins and related compounds, DDTs, CHLs and HCB in human breast milk from primiparae were comparable to or slightly higher than the data obtained during 1998, indicating that the levels of these contaminants in Japanese human breast milk have not decreased since 1998 and Japanese are continuously exposed to these chemicals, presumably via fish intake. In addition, OC levels in human breast milk from primiparae were significantly higher than those from multiparae, implying elimination of OCs via lactation. Furthermore, significant positive correlations were observed between levels of OCs in human breast milk and the age of primiparae. These results indicate that the mothers with higher age may transfer higher amounts of OCs to the first infant than to the infants born afterwards through breast-feeding, and hence the first born children might be at higher risk by OCs. (c) 2005 Elsevier Ltd. All rights reserved.
  • Graeme Allinson, Cindi Mispagel, Natsuko Kajiwara, Yasumi Anan, Junko Hashimoto, Laurie Laurenson, Mayumi Allinson, Shinsuke Tanabe
    CHEMOSPHERE 64 (9) 1464 - 1471 0045-6535 2006/08 [Peer-reviewed]
     Scientific journal 
    In recent times, the apparent population decline of the southern bent-wing bat (Miniopterus schreibersii bassanii) at Bat Cave, acoorte has been ascribed to pesticide use in the region, following the finding of organochlorine and orgaonophosphate insecticide idues in bat guano. Adult southern bent-wing bats were collected from Bat Cave and Starlight Cave in 2003. Organochlorine contaminants were detected in all carcass samples: p,p'-DDE was by far the most dominant contaminant with concentrations from 11 000 to 59000 ng g(-1), followed by p,p'-DDT (110-1600 ng g(-1)), p,p'-DDD (35-620 ng g(-1)), Sigma PCBs (33-490 ng g(-1)), chlordane and related compounds (7.9-270 ng g(-1)), HCB (1.6-120 ng g(-1)), HP epox. (3.1-230 ng g(-1)), TCPMOH (3.8-38 ng g(-1)), Sigma HCHs (1.4-9.6 ng g(-1)), and TCPMe (0.1-4.2 ng g(-1)) (all values on lipid-weight basis). No significant difference in DDE, DDD, DDT, Sigma DDT, Sigma PCB, trans-chlordane, heptachlor epoxide, trans-nonachlor, alpha-HCH, beta-HCH, gamma-HCH, TCPMOH or TCPMe concentrations observed either between sexes within sites, or between sites (p > 0.05). However, there were significant differences in HCB and dane concentrations between sexes and between sites (p < 0.05), between site differences in cis-nonachlor concentrations in male (p < 0.05), and cis-chlordane concentrations between sexes at Starlight Cave, and between males of each site (P < 0.05). There were significant differences in the liver concentrations of some metals between sexes within sites (Ag, Cd, Co, Cu, Ph, Se, Zn), and sites (Ag, Cd, Co, Cu, Hg, Pb, Se, V, Zn). Clustering or grouping of sites was observed when the OC data was expressed on a basis. These inter-site differences in OC concentrations reflect local exposure over a period of time, and do not unambiguously any suggestion that we are witnessing incipient speciation. However, for conservation purposes, it may be prudent to assume that are two sub-populations of M. s. bassani feeding in different locations in this region of southern Australia, rather than the single geneous population suggested by genetic studies. (c) 2006 Elsevier Ltd. All rights reserved.
  • Suzuki Yoshinari, Watanabe Izumi, Tanabe Shinsuke, Kuno Katsuji
    CHEMOSPHERE 64 (8) 1296 - 1310 0045-6535 2006/08 [Peer-reviewed]
  • T. B. Minh, M. Watanabe, N. Kajiwara, H. Iwata, S. Takahashi, A. Subramanian, S. Tanabe, S. Watanabe, T. Yamada, J. Hata
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 51 (2) 296 - 313 0090-4341 2006/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorines (OCs)-such as polychlorinated biphenyls (PCBs), 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene, and tris(4-chlorophenyl)methane [TCPMe]-were determined in plasma samples from residents of three sub-metropolitan locations in Japan (Miyako, Saku, and Tottori) for the purpose of studying the geographic variation and specific accumulation of OCs. Residue concentrations of PCBs and DDTs were the highest in samples collected in Saku (400 and 370 ng/g lipid wt, respectively) whereas samples from Miyako contained greater CHL residues (70 ng/g lipid wt) than those from the other two locations. This contamination pattern reflects the historic use of OCs in each area. For the first time, tris (4-chlorophenyl) methane (TCPMe) concentrations were detected in most of the plasma sample analyzed. Concentrations of TCPMe which ranged from < 0.1 to 8.1 ng/g lipid wt eight, were lower than those previouly reported in other human tissue. Larger geographic differences in OC accumulation were observed for PCBs and CHLs, whereas DDTs and HCHs exhibited little variability. PCB concentrations in samples from Saku residents were higher than those from residents of countries in the circumpolar Arctic region but lower than those reported for some populations in the United States and Western European countries. Interestingly, CHL residue concentrations in human blood from Japan are among the highest values reported for the countries examined, suggesting continued increased exposure to CHLs of the Japanese population. Time-trend analysis of CHLs in human blood samples from Miyako (Okinawa prefecture) showed that CHL residues have decreased substantially during the last decade, indicating the effect of the official ban of CHLs in 1986 in Japan. Isomer-specific analysis of PCBs revealed lower proportions of higher chlorinated congeners such as hepta- and octachlorobiphenyls in women than in men, suggesting the possibility of preferential elimination of higher chlorinated biphenyls in women. The difference in sex-dependent accumulation of OC compounds in healthy and ill persons was suggested. To our knowledge, this is the first report on the specific accumulation of persistent QCs, including TCPMe, in human blood samples from Japan.
  • Natsuko Kajiwara, Satoko Kamikawa, Karri Ramu, Daisuke Ueno, Tadasu K. Yamada, Annamalai Subramanian, Paul K. S. Lam, Thomas A. Jefferson, Maricar Prudente, Kyu-Flyuck Chung, Shinsuke Tanabe
    CHEMOSPHERE 64 (2) 287 - 295 0045-6535 2006/06 [Peer-reviewed]
     Scientific journal 
    Polybrominated diphenyl ethers (PBDEs) are one of the flame retardants widely used in plastics. textiles. electronic appliances, and electrical household appliances. In this study, PBDEs and organochlorine compounds (OCs) were determined in the archived samples from the Environmental Specimen Bank for Global Monitoring (es-BANK) at Ehime University. The blubber of cetaceans found stranded along the coasts of Japan, Hong Kong, the Philippines and India during the period from 1990 to 2001 were employed for chemical analysis to understand the present status of contamination and the specific accumulation of PBDEs. PBDEs were detected in all the cetacean samples analyzed, and concentrations were one or two orders of magnitude lower than for PCBs and DDTs. Concentrations of PBDEs ranged from a low value of 6.0 ng/g lipid wt. in spinner dolphin (Stenella longirostris.) from India to a high value of 6000 ng/g lipid wt. in Indo-Pacific humpback dolphin (Sousa chinensis) from Hong Kong. No difference in PBDE levels between coastal and offshore species from Japan was observed, implying the existence of pollution Sources in this region other than Japan. Highest concentrations of PBDEs were found in animals from Hong Kong. followed by Japan. and much lower levels from the Philippines and India, suggesting that developing nations may also have pollution sources of PBDEs. Geographical distribution of PBDEs in Asian waters was different from PCBs but similar to DDTs. (c) 2005 Elsevier Ltd. All rights reserved.
  • NH Minh, TB Minh, N Kajiwara, T Kunisue, A Subramanian, H Iwata, TS Tana, R Baburajendran, S Karuppiah, PH Viet, BC Tuyen, S Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 50 (4) 474 - 481 0090-4341 2006/05 [Peer-reviewed]
     Scientific journal 
    In Asian developing countries, large amounts of municipal wastes are dumped daily in open dumping sites without proper management. This practice may cause several adverse environmental consequences and increased health risk to local communities. To elucidate contamination by persistent organic pollutants (POPs)-including dichloro-diphenyl-trichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), chlordanes, hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs)-in such dumping sites, soil samples were collected from open dumping sites and respective control sites in Cambodia, India, and Vietnam from 1999 through 2001. Our results demonstrated that DDTs, PCBs, and HCHs were dominant contaminants in the dumping sites. However, the contamination pattern was not consistent, showing higher HCHs in India than in Cambodia and Vietnam. Interestingly, in all of the countries, extremely higher levels of POPs were observed in the dumping sites compared with those in the respective control sites, suggesting significant amplification of POP contamination in the dumping sites of Asian developing countries. Mean concentrations of DDTs and PCBs were 350 and 140 ng/g dry weight, respectively, in the dumping sites of Cambodia and 26 and 210 ng/g, respectively, in India. These residue levels were hundreds to thousands times higher than those in general soils, implying possible risk to human health of the local communities, especially to the rag pickers, including children who work in these sites to collect recyclable materials. Composition of DDT compounds suggested their recent use in populated areas, which in turn might have caused increased levels of DDTs in the open dumping sites. In addition, composition of HCH isomers revealed their different use pattern in different countries.
  • J Yang, N Miyazaki, T Kunito, S Tanabe
    CHEMOSPHERE 63 (3) 449 - 457 0045-6535 2006/04 [Peer-reviewed]
     Scientific journal 
    Concentrations and body burdens of 14 trace elements (Hg, Cr, Mn, Co, Cu, Zn, Sr, Ag. Cd, V, Se, Pb, Mo. and Fe) and butyltins (BTs) (tributyltin TBT, dibutyltin DBT, and monobutyltin MBT) were determined in various tissues of a mature male Dall's porpoise (Phocoenoides dalli) collected off the Sanriku coast of Japan. Selective accumulation in this porpoise was observed for Hg, Mn, Cu, Ag, Mo, Fe, and total BTs (TBT, DBT, and MBT) in the liver, Cd in the kidney, Zn, Sr, V, Pb, and Co in the bone, and Se in the skin. In contrast, Cr concentrations in all tissues were similar. This distribution pattern in this mature porpoise was in general agreement with the accumulation characteristics of trace elements and butyltins reported for other marine mammals. The whole body of the porpoise contained approximately 62 g Fe, 8.8 g Zn, 4.0 g Sr, 0.6 g Se, 0.41 g Cu, 0.19 g Hg, 0.17 g Cd, 0.16 g Mn, 0.05 g Cr. 0.009 g Ag, 0.008 g Mo, 0.005 g Pb, 0.004 g Co, and 0.7 mg of BTs (0.4 mg TBT, 0.2 mg DBT, and 0.1 mg MBT). Metabolism of TBT to its breakdown products of this porpoise seems to be limited, since TBT still accounted for about half of the total burden of BTs. As in the cases of Hg, Mn, Cu, Se, and Fe, the muscle was the most important reservoir (43%) for the whole body burden of total BTs, 80% of which was TBT, and thus muscle played a crucial role in the higher body composition of TBT in this Dail's porpoise. (c) 2005 Elsevier Ltd. All rights reserved.
  • Akira Kubota, Hisato Iwata, Shinsuke Tanabe, Kumiko Yoneda, Sachiko Tobata
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 25 (4) 1007 - 1016 0730-7268 2006/04 [Peer-reviewed]
     Scientific journal 
    Concentrations of dioxins and related compounds (DRCs), such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated bipherryls (Co-PCBs), were determined in black-eared kites (BEKs; Milvus migrans) collected from the Kanto district in Japan. Total 2,3,7,8-tetra-CDD toxic equivalents (TEQs) were in the range of 99 to 3,800 pg/g lipid weight in the liver and 42 to 760 pg/g lipid weight in the pectoral muscle. Three congeners, including PCB 126, 2,3,4,7,8-penta-CDF, and 1,2,3,7,8-penta-CDD, made a greater contribution to total TEQs in both tissues. Levels of ethoxyresorufi n-O-deethy lase activity and a cross-reactive protein with anti-rat cytochrome P4501 A (CYPIA) polyclonal antibodies showed no significant correlation with hepatic TEQs. This may be attributed to low sensitivity and insufficient TEQ levels to cause CYPIA induction, high metabolic potential of a series of congeners, and influence of CYPIA inducers other than DRCs. Most of the PCDD/ Fs and non-ortho Co-PCBs exhibited a total TEQ- and CYPIA-dependent increase in the liver to muscle concentration ratios, implying their concentration-dependent hepatic sequestration in which CYPIA was involved. Comparison of the toxicokinetics in avian species revealed that BEKs possibly have higher potentials than common cormorants for metabolizing and sequestering certain congeners in the liver in terms of hepatic concentration profiles and liver:muscle concentration ratios, respectively. These results clearly indicate that the toxicokinetics of DRCs is congener-, tissue-, and species-specific as well as concentration-dependent. Therefore, CYPIA expression is one of the critical factors that determine the toxicokinetics in wild avian species.
  • T Kunisue, MX Watanabe, H Iwata, T Tsubota, F Yamada, M Yasuda, S Tanabe
    ENVIRONMENTAL POLLUTION 140 (3) 525 - 535 0269-7491 2006/04 [Peer-reviewed]
     Scientific journal 
    The present study determined the contamination levels and congener-specific accumulation features of dioxins and related compounds (DRCs) in wild terrestrial mammals such as large Japanese field mice (LJFM), lesser Japanese moles (LJMs), and raccoon dogs (RDs) collected from Kanto region in Japan during 2001. The toxic equivalent quantity (TEQ) levels in the carcasses or adipose tissues were in the order of RDs >= LJMs > LJFM. Comparison of DRC congener profiles in the three species and principal component analysis (PCA) demonstrated a higher contribution of OCIDD, T(4)CB77, and P(5)CB118 in LJMs. Analysis of liver-adipose distribution of DRC congeners in RDs showed that livers contained significantly higher TEQs than adipose tissues, indicating that liver is a depository organ and critical for determining the toxicokinetics of DRCs. As for most T-4, P-5, H6CDD/DFs and for P(5)CB126, H(6)CB169 and mono-ortho PCB congeners, their liver/adipose concentration ratios in RDs revealed a tendency to increase with hepatic TEQ levels, suggesting TEQ-dependent hepatic sequestration. (c) 2005 Elsevier Ltd. All rights reserved.
  • R Kubota, T Kunito, T Agusa, J Fujihara, Monirith, I, H Iwata, A Subramanian, TS Tana, S Tanabe
    JOURNAL OF ENVIRONMENTAL MONITORING 8 (2) 293 - 299 1464-0325 2006/02 [Peer-reviewed]
     Scientific journal 
    Arsenic concentrations in hair and urine, and urinary levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative DNA damage, were examined for inhabitants of the Mekong Basin in Kratie Province, Cambodia. Also, the arsenic levels of tube-well water were determined. Total arsenic concentrations in tube-well water ranged from < I to 886 mu g L-1, and 44.8% of these exceeded the WHO drinking water guideline of 10 mu g L-1. Elevated levels of arsenic were observed in the human hair and urine, and also a significant positive correlation was observed between the concentrations in hair and urine. These results suggest that the inhabitants are chronically exposed to arsenic through drinking the tube-well water. Levels of urinary 8-OHdG were higher for the subjects with higher arsenic levels in hair and urine, suggesting that induction of oxidative DNA damage was caused by chronic exposure to arsenic in tube-well water for the inhabitants in Kratie Province. To our knowledge, this is the first report on the oxidative DNA damage caused by chronic exposure to arsenic in groundwater for the inhabitants in Cambodia.
  • K Nakayama, H Iwata, EY Kim, K Tashiro, S Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 40 (3) 1076 - 1083 0013-936X 2006/02 [Peer-reviewed]
     Scientific journal 
    To establish a monitoring system for gene expression profiles related to chemical contamination in wild common cormorants (Phalacrocorax carbo), the present study constructed an oligo array designed from expressed sequence tag (EST) sequences of the cormorant liver, where 1061 unique oligonucleotides were spotted. Common cormorants were collected from Lake Biwa, Japan in May 2001 and 2002. With the use of this oligo array, gene expression profiles in the liver of individual specimens were evaluated. To determine the expression patterns of genes altered by environmental contaminants, relationships between concentrations of persistent organochlorines including polychlorinated dibenzo-p-dioxins, furans, polychlorinated biphenyls, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane and its metabolites (DOTS), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), butyltins, and bisphenol A (BPA) and expression levels of each gene in the cormorant liver were examined using stepwise multiple regression analysis. The reliability of data obtained by the oligo array was further confirmed by quantifying the expression levels of certain genes using real-time RTPCR. The 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent (TEQ) level was positively correlated with both cytochrome P4501A4 and 1A5 gene expression. In addition, the mRNA level of an antioxidant enzyme, Cu/Zn superoxide dismutase, was negatively correlated with hepatic total TEQ. Other antioxidant enzymes, glutathione peroxidase 3 and glutathione S-transferase class mu, were negatively correlated with HCHs and BPA levels, respectively. The mRNA expression level of a nonenzymatic antioxidant, haptoglobin, was negatively but not significantly correlated with CHLs. These results led to a hypothesis that wild cormorant population may suffer from oxidative stress due to chemically induced formation of reactive oxygen species and subsequent reduction of antioxidant resistance. Thus, the cormorant oligo array may be a useful monitoring tool to identify specific gene expression profiles altered by various environmental contaminants. Although further research is required to clarify a definitive cause-and-effect relationship, the current study provides valuable information on contaminant-responsive genes to predict potential effects on wildlife in a real environment.
  • 上田浩三, 浜野修史, 岩本智史, 山本常平, 梅村省三, 田辺信介
    環境資源工学 53 (3) 134 - 141 2006 [Peer-reviewed]
  • A Sudaryanto, T Kunisue, N Kajiwara, H Iwata, TA Adibroto, P Hartono, S Tanabe
    ENVIRONMENTAL POLLUTION 139 (1) 107 - 117 0269-7491 2006/01 [Peer-reviewed]
     Scientific journal 
    This study determined concentrations of polychlorinated biphenyls (PCBs) and organochlorine compound (OC) pesticides in the milk samples of women from the general population in four locations of Indonesia. The most prevalent residues of OCs were DDTs, PCBs and hexachlorocyclohexane isomers (HCHs), whereas other OCs such as chlordane compounds (CHLs), tris(4-chlorophenyl)methane and hexachlorobenzene were lower. The levels of OCs varied between locations and individuals, with DDTs higher in suburban and rural areas than urban localities, may be due to the differences in food habits and sources between the individuals and locations. Data from Purwakarta site indicated continuing DDT exposure, which may confirm recent usage of DDT in Indonesia. A positive correlation was observed between concentration of OCs in human milk and age of mothers, primiparas women having higher OCs than multiparas, suggesting these parameters play an important role influencing the OC burdens in lactating women. Some individuals accumulated DDTs and HCHs in breast milk close to or even higher than the TDI (tolerable daily intake) guidelines proposed by Health Canada. (c) 2005 Elsevier Ltd. All rights reserved.
  • T Agusa, T Kunito, J Fujihara, R Kubota, TB Minh, PTK Trang, H Iwata, A Subramanian, PH Viet, S Tanabe
    ENVIRONMENTAL POLLUTION 139 (1) 95 - 106 0269-7491 2006/01 [Peer-reviewed]
     Scientific journal 
    Concentrations of As and other trace elements and their association were examined in groundwater (n=25) and human hair (n=59) collected at Gia Lam District and Thanh Tri District, suburban areas of Hanoi, Vietnam, in September 2001. Concentrations of As in the groundwater ranged from < 0.10 to 330 mu g/l, with about 40% of these exceeding WHO drinking water guideline of 10 mu g/l. Also, 76% and 12% of groundwater samples had higher concentrations of Mn and Ba than WHO drinking water guidelines, respectively. Arsenic concentrations in hair of residents in Gia Lam and Thanh Tri Districts (range 0.088-2.77 mu g/g dry wt.) were lower than those in other As-contaminated areas of the world, but were higher than those of people in noncontaminated areas. Concentrations of As and Mn in hair of some individuals from the Gia Lam and Thanh Tri Districts exceeded the level associated with their toxicity and, therefore, a potential health risk of As and Mn is a concern for the people consuming the contaminated water in this area. Cumulative As exposure was estimated to be lower than the threshold levels at the present, which might explain the absence of manifestations of chronic As poisoning and arsenicosis in the residents of Gia Lam and Thanh Tri Districts. To our knowledge, this study revealed for the first time that the residents are exposed not only to As but also Mn and Ba from groundwater in the Red River Delta, Vietnam. (c) 2005 Elsevier Ltd. All rights reserved.
  • MX Watanabe, H Iwata, M Okamoto, EY Kim, K Yoneda, T Hashimoto, S Tanabe
    TOXICOLOGICAL SCIENCES 88 (2) 384 - 399 1096-6080 2005/12 [Peer-reviewed]
     Scientific journal 
    This study presents concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like coplanar PCBs (Co-PCBs) in the liver and breast muscle of jungle crows (JCs; Corvus macrorhynchos) collected from Tokyo, Japan. 2,3,7,8-Tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) derived by WHO bird-TEF were in the range of 23 to 280 pg/g (lipid) in the liver, which are lower or comparable to the lowest-observed-effect-level of CYP induction in chicken, and 5.6-78 pg/g (lipid) in the pectoral muscle. Cytochrome P450 (CYP) 1A-, 2B-, 2C-, and 3A-like proteins were detected using anti-rat CYP polyclonal antibodies in hepatic microsomal fractions. Significant (p < 0.05) positive correlations between hepatic TEQs and CYP1A or CYP3A-like protein expression levels were noticed, implying induction of these CYP isozymes by TEQs. On the other hand, there was no significant positive correlation between muscle TEQ and any one of analyzed CYP isozyme expression levels. CYP1A- and CYP3A-like protein expression levels represented better correlations with pentoxy- and benzyloxyresorufin-O-dealkylase activities rather than methoxy- and ethoxyresorufin-O-dealkylase activities, indicating unique catalytic functions of these CYPs in JCs. Furthermore, we succeeded in isolating CYP1A5 cDNA from the liver of JC, having an open reading frame of 531 amino acid residues with a predicted molecular mass of 60.3 kDa. JC CYP1A5 mRNA expression measured by real-time RT-PCR had a significant positive correlation with hepatic TEQs, suggesting induction of CYP1A5 at the transcriptional level. Ratios of several Co-PCB congeners to CB-169 in the liver of JCs revealed significant negative correlations with CYP1A protein or CYP1A5 mRNA expression levels, implying metabolism of these congeners by the induced CYP1A. The liver/breast muscle concentration (L/M) ratios of PCDDs/DFs and CB-169 increased with an increase in hepatic CYP1A protein or CYP1A5 mRNA expression levels, suggesting congener-specific hepatic sequestrations by the induced CYP1A. The present study provides insights into the propensity of CYP1A induction to the exposure of dioxin-like chemicals, and unique metabolic and sequestration capacities of CYP1A in JC.
  • DH Nam, Y Anan, T Ikemoto, S Tanabe
    MARINE POLLUTION BULLETIN 50 (11) 1347 - 1362 0025-326X 2005/11 [Peer-reviewed]
     Scientific journal 
    This study was aimed at determining multielemental concentration and its intracellular distribution in selected tissues of cormorant and waterfowl species. Non-essential elements Such as Hg, Tl, Cd, Ph and V in tissues were generally consistent with those in ingested items, indicating the significance of food sources of non-essential metal accumulation in great cormorants and mallards. Great cormorants and four waterfowl species examined reflected natural background levels of toxic metals Such as Cd, Hg and Pb as well as some essential elements, indicating no specific metal exposure from local sources. Most of Cu, Zn, Se, Rb, Ag, Cd, Cs, and Fig contents were present in the hepatocytosolic fraction, whereas a large percentage of V and Mo were present in insoluble fraction in great cormorant, mallard, and spot-billed duck. The major role of these subeelluar fractions in elemental regulation accounts for the high percentage contribution of each cellular fraction to the total metal contents. Cadmium and Cu are chiefly sequestered through binding to rnetallothioneins (MTs) of hepatocytosolic fraction in these three avian species. Both MTs and high-molecular-weight substance (HMWS) for Zn and low-molecular-weight Substance (LMWS) for Rb were also involved in their sequestration in cytosolic fractions. Relatively different species-specific cytosolic substances were responsible for varying degrees of Ag, Mn, and Co accumulation. It is worth noting that these intracellular metal levels in birds are closely regulated by metal-associated cellular constituents. Therefore, risk assessment studies of metal accumulation in such wild birds should take intracellular metal distribution and specific cellular constituents into account. (c) 2005 Elsevier Ltd. All rights reserved.
  • A Sudaryanto, T Kunisue, S Tanabe, M Niida, H Hashim
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 49 (3) 429 - 437 0090-4341 2005/10 [Peer-reviewed]
     Scientific journal 
    This study determined the concentrations of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides, and tris(4-chlorophenyl) methane (TCPMe) in human breast milk samples collected in 2003 from primipara mothers living in Penang, Malaysia. OCs were detected in all the samples analyzed with DDTs, hexachlorocyclohexane isomers (HCHs), and PCBs as the major contaminants followed by chlordane compounds (CHLs), hexachlorobenzene (HCB), and TCPMe. The residue levels of DDTs, HCHs, and CHLs were comparable to or higher than those in general populations of other countries, whereas PCBs and HCB were relatively low. In addition, dioxins and related compounds were also detected with a range of dioxin equivalent concentrations from 3.4 to 24 pg-TEQs/g lipid wt. Levels of toxic equivalents (TEQs) were slightly higher than those in other developing countries but still much lower than those of industrialized nations. One donor mother contained a high TEQs level, equal to the mean value in human breast milk from Japan, implying that some of the residents in Malaysia may be exposed to specific pollution sources of dioxins and related compounds. No association was observed between OCs concentrations and maternal characteristics, which might be related to a limited number of samples, narrow range of age of the donor mothers, and/or other external factors. The recently identified endocrine disrupter, TCPMe, was also detected in all human breast milk samples of this study. A significant positive correlation was observed between TCPMe and DDTs, suggesting that technical DDT might be a source of TCPMe in Malaysia. The present study provides a useful baseline for future studies on the accumulations of OCs in the general population of Malaysia.
  • K Kannan, K Ramu, N Kajiwara, RK Sinha, S Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 49 (3) 415 - 420 0090-4341 2005/10 [Peer-reviewed]
     Scientific journal 
    The Irrawaddy dolphin (Orcaella brevirostris) is at risk of extinction throughout its range as a result of incidental catches, habitat degradation, and pollution. Populations of Irrawaddy dolphins are constrained by the species' narrow habitat requirement-lagoons, estuaries, rivers, and lakes-and are therefore particularly vulnerable to the effects of human activities. In this study, for the first time, concentrations of organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in tissues of Irrawaddy dolphins collected from Chilika Lake, India, to understand the status of contamination. Dichlorodiphenyltrichloroethane and its metabolites (DDTs) were the predominant contaminants found in Irrawaddy dolphins; the highest concentration found was 10,000 ng/g lipid weight in blubber. Hexachlorocyclohexanes (HCHs) were the second most prevalent contaminants in dolphin tissues. Concentrations of PCBs, chlordanes, hexachlorobenzene, tris(4-chlorophenyl)methane, and tris(4-chlorophenyl)methanol were in the ranges of few ng/g to few hundreds of ng/g on a lipid-weight basis. In general, concentrations of OC pesticides and PCBs in Irrawaddy dolphins were lower than the concentrations reported for coastal and riverine dolphins collected in Asia. PBDEs were detected in the blubber of Irrawaddy dolphins at concentrations ranging from 0.98 to 18 ng/g lipid weight. BDE congener 47 accounted for 60% to 75% of the total PBDE concentrations. Although these results establish the baseline levels of persistent organic pollutants in Irrawaddy dolphins, efforts should be made to decrease the sources of contamination by DDTs and HCHs in Chilika Lake.
  • Jun Sekizawa, Shinsuke Tanabe
    Toxicology and Applied Pharmacology 207 (2) S617 - S622 0041-008X 2005/09 [Peer-reviewed]
     International conference proceedings 
    Both humans and wildlife are exposed to various types of halogenated organic compounds such as polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT), typically old chemicals, and tris(4-chlorophenyl) methane (TCPM) and brominated flame retardants, some new chemicals, simultaneously. Classical risk assessment has evaluated health and ecological risks independently by experts from different disciplines. Taking into considerations the recent concerns about endocrine disrupting chemicals and the progress of research in related areas, we integrated and assessed data on exposure and potential effects in humans and wildlife. Comparisons were made for organ concentrations, body burdens of several organochlorine compounds (OCs), metabolic capacities between humans and various wildlife. When we integrate the knowledge on effects and exposure in humans and in wildlife, new insights were suggested about similarities and/or differences in potential effects among various human populations living on different foods and having different body burdens. Combining existing information with emerging knowledge of mechanisms of actions on endocrine disrupting chemicals after exposure to above chemicals during early developmental stages will further elucidate potential risks from exposure to those chemicals. © 2005 Elsevier Inc. All rights reserved.
  • T Agusa, T Matsumoto, T Ikemoto, Y Anan, R Kubota, G Yasunaga, T Kunito, S Tanabe, H Ogi, Y Shibata
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 24 (9) 2107 - 2120 0730-7268 2005/09 [Peer-reviewed]
     Scientific journal 
    Body distribution and maternal transfer of 18 trace elements (V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Hg, Tl, and Pb) to eggs were examined in black-tailed gulls (Larus crassirostris), which were culled in Rishiri Island, Hokkaido Prefecture, Japan. Manganese, Cu, Rb, Mo, and Cd showed the highest levels in liver and kidney, Ag, Sb, and Hg in feather, and V, Sr, and Pb in bone. Maternal transfer rates of trace elements ranged from 0.8% (Cd) to as much as 65% (TI) of maternal body burden. Large amounts of Sr, Ba, and TI were transferred to the eggs, though maternal transfer rates of V, Cd, Hg, and Ph were substantially low. It also was observed that Rb, Sr, Cd, Cs, and Ba hardly were excreted into feathers. Concentrations of Co in liver, Ba in liver and kidney, and Mo in liver increased significantly with age, whereas Se in bone and kidney, Hg in kidney, and Cr in feather decreased with age in the known-aged black-tailed gulls (2-20 years old). It also was suggested that feathers might be useful to estimate contamination status of trace elements in birds, especially for Hg on a population basis, although the utility is limited on an individual basis for the black-tailed gulls. To our knowledge, this is the first report on the maternal transfer rate of multielements and also on the usefulness of feathers to estimate contamination status of Hg in birds on a population basis.
  • T Kunisue, S Nakanishi, M Watanabe, T Abe, S Nakatsu, S Kawauchi, A Sano, A Horii, Y Kano, S Tanabe
    ENVIRONMENTAL POLLUTION 136 (3) 465 - 476 0269-7491 2005/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorines (OCs) such as polychlorinated dibenzo-p-dioxin (PCDDs), dibenzofurans (PCDFs), biphenyls, dichlorodiphenyltrichloroethane and their metabolites (DDTs), hexachlorocyclohexane isomers, hexachlorobenzene, and chlordane compounds were determined in genital organs of pet dogs and cats and pet foods from Japan. Levels of OCs in dogs were relatively lower than those in cats, while residue levels in their diets were almost similar, implying that accumulation and elimination mechanisms of these contaminants are different between dogs and cats. When bioconcentration factors (BCFs) were estimated from concentrations of OCs in dogs, cats, and their diets, BCFs of all the OCs except PCDD/DFs exceeded 1.0 in cats. On the other hand, in all the dogs, BCFs of DDTs were below 1.0, suggesting that dogs do not bioconcentrate DDTs. Furthermore, BCFs of all the OCs except PCDD/DFs in dogs were notably lower than those in cats, suggesting that dogs have higher metabolic and elimination capacity for these contaminants than cats. When residue levels of OCs in livers, adipose tissue, and genital organs of two pet dogs were examined, hepatic sequestration of PCDD/DFs and oxychlordane was observed. (c) 2005 Elsevier Ltd. All rights reserved.
  • EY Kim, H Iwata, T Suda, S Tanabe, M Amano, N Miyazaki, EA Petrov
    COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY 141 (3) 281 - 291 1532-0456 2005/07 [Peer-reviewed]
     Scientific journal 
    Most toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related planar halogenated aromatic hydrocarbons (PHAHs) are mediated by ligand-activated aryl hydrocarbon receptor (AHR) signaling pathway. To understand the regulation mechanism of AHR and AHR nuclear translocator (ARNT) expression in wild Baikal seal (Pusa sibirica) population contaminated by PHAHs, the present study investigated hepatic mRNA expression levels of AHR and its heterodimer, ARNT genes, in association with biological index (age, gender and body weight), PHAH accumulation and expression levels of cytochrome P450 (CYP) 1A and 1B. While there was no gender difference, the AHR mRNA expression levels were increased with ages (p =0.014) and body weights (p=0.015), indicating that AHR expression might be affected by these biological factors. The AHR mRNA expression levels exhibited significant positive correlations with total TEQs and most of individual congener TEQs derived from polychorinated dibenzo-p-dioxins, dibenzofurans and non-ortho coplanar polychorinated biphenyls (PCBs), indicating the transcriptional up-regulation of AHR expression by these congeners. On the other hand, there was no significant correlation between individual TEQs from mono-ortho coplanar PCBs and AHR expression. These results imply the structure-related transcriptional activity of AHR among PHAHs congeners. AHR mRNA levels showed positive correlations with both CYP1A protein (p=0.039) and CYP1A1 mRNA expression levels (p=0.046). In contrast to AHR expression, neither the total nor individual congener TEQs influenced ARNT at the transcriptional level. ARNT mRNA showed significant negative correlations with CYP1A/1B protein (p = 0.027 and p = 0.006) and CYP1A1 mRNA expression levels (p = 0.039), implying the existence of different transcriptional regulation between AHR and ARNT genes and negative regulation by CYP1A/1B-mediated signaling pathways. The present findings may render significant insight on the basic mechanisms underlying regulation of AHR and ARNT expressions associated with biological factors and PHAH exposure in wild mammalian populations. (C) 2005 Elsevier Inc. All rights reserved.
  • D Ueno, M Watanabe, AL Subramanian, H Tanaka, G Fillmann, PKS Lam, GJ Zheng, M Muchtar, H Razak, M Prudente, KH Chung, S Tanabe
    ENVIRONMENTAL POLLUTION 136 (2) 303 - 313 0269-7491 2005/07 [Peer-reviewed]
     Scientific journal 
    In order to elucidate the global distribution of dioxins and related compounds, such as PCDDs, PCDFs and coplanar PCBs, levels of these compounds were determined in the muscle of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters and open seas near Japan, Taiwan, Philippines, Indonesia, Seychelles and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Indian Ocean and the North Pacific Ocean. PCDDs, PCDFs and coplanar PCBs were detected in almost all the specimens collected from all the locations surveyed, indicating widespread contamination by these compounds in the marine environment. Higher concentrations of dioxins and coplanar PCBs were detected in the samples from temperate Asian regions, plausibly due to larger usage and anthropogenic generation in highly industrialized countries around the East China Sea and the South China Sea, such as Japan, Korea, Taiwan, Hong Kong and coastal China. © 2005 Elsevier Ltd. All rights reserved.
  • M Yamauchi, EY Kim, H Iwata, S Tanabe
    COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY 141 (2) 177 - 187 1532-0456 2005/06 [Peer-reviewed]
     Scientific journal 
    The aryl hydrocarbon receptor (AHR) mediates the toxic effects of planar halogenated aromatic hydrocarbons (PHAHs). Bony fishes exposed to PHAHs exhibit a wide range of developmental defects. However, functional roles of fish AHR are not yet fully understood, compared with those of mammalian AHRs. To investigate the potential sensitivity to PHAHs toxic effects, an AHR cDNA was initially cloned and sequenced from red seabream (Pagrus major), an important fishery resource in Japan. The present study succeeded in identifying two highly divergent red seabream AHR cDNA clones, which shared only 32% identity in full-length amino acid sequence. The phylogenetic analysis revealed that one belonged to AHR1 clade (rsAHR1) and another to AHR2 clade (rsAHR2). The rsAHR1 encoded a 846-residue protein with a predicted molecular mass of 93.2 kDa, and 990 amino acids and 108.9 kDa encoded rsAHR2. In the N-terminal half, both rsAHR genes included bHLH and PAS domains, which participate in ligand binding, AHR/ARNT dimerization and DNA binding. The C-terminal half, which is responsible for transactivation, was poorly conserved between rsAHRs. Quantitative analyses of both rsAHRs mRNAs revealed that their tissue expression profiles were isoform-specific; rsAHR1 mRNA expressed primarily in brain, heart, ovary and spleen, while rsAHR2 mRNA was observed in all tissues examined, indicating distinct roles of each rsAHR. Furthermore, there appeared to be species-differences in the tissue expression profiles of AHR isoforms between red seabream and other fish. These results suggest that there are isoform- and species-specific functions in piscine AHRs. (c) 2005 Elsevier Inc. All rights reserved.
  • MX Watanabe, H Iwata, M Watanabe, S Tanabe, A Subramanian, K Yoneda, T Hashimoto
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 39 (12) 4421 - 4430 0013-936X 2005/06 [Peer-reviewed]
     Scientific journal 
    To assess the significance of waste dumping sites as a source of chemical contamination to ecosystems, we analyzed the residue levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and other organochlorines in the breast muscle of crows from a dumping site in the south of Chennai city, South India. Crows from the dumping site contained significantly higher total TEGs (60 +/- 27 pg/g lipid wt) than those from the reference sites (26 +/- 18 pg/g lipid wt). Especially, certain dioxin-like coplanar PCB congeners (Co-PCBs), such as CB-77 and CB-105, whose source iscommercial PCBs,were significantly higher in crows from the dumping site than those from the reference sites. Profiles of PCDDs/DFs and Co-PCBs in crows from the dumping site were similar to those of soil at the same site, which was confirmed by principal component analysis. Furthermore, significant positive correlations were obtained between the congener-specific bioconcentration factors (BCFs) of PCDDs/DFs estimated from concentrations in crows and soil from the dumping site and the theoretical BCFs calculated from water-particle and lipid-water partitioning coefficients. On the other hand, the estimated BCFs had significant negative correlations with the molecular weight of PCDDs/DFs, indicating that molecular size limits their bioaccumulation. These results suggest that dioxin-like congeners in the soil of the dumping site were transferred directly to the crows through the ingestion of on-site garbage contaminated with soil, ratherthan through trophic transfer in the ecosystem. The present study provides insight into the ecological impacts of dumping sites.
  • JCW Lam, S Tanabe, MHW Lam, PKS Lam
    ENVIRONMENTAL POLLUTION 135 (3) 481 - 490 0269-7491 2005/06 [Peer-reviewed]
     Scientific journal 
    Concentrations of 17 trace elements (As, Se, Rb, Sr, Ag, Sb, Cs, Tl, Ph, V, Cr, Mn, Co, Cu, Zn, Cd, and Hg) were determined in eggs of little egrets (Egretta garzetta), black-crowned night herons (Nycticorax nycticorax) and bridled terns (Sterna anaethetus) from northwestern and northeastern coastal areas of Hong Kong. Results indicated significant differences among the three species. Eggs of little egrets and black-crowned night herons appeared to be good bioindicators for monitoring selected elements (As, Pb, Zn Cr, Cu, and V) due to consistent correlations between metal concentrations in eggs and those in coastal marine sediments. Based on limited toxicological information, the predicted no effect concentrations (PNECs) of Hg and Se in the bird eggs were estimated as 0.5 to 1.8 and 0.90 to 1.45 mu g g(-1), dry wt., respectively. Hazard quotients (HQs) indicated that Hg and Se might pose some risk to certain waterbirds in Hong Kong. (c) 2005 Elsevier Ltd. All rights reserved.
  • A Kubota, H Iwata, S Tanabe, K Yoneda, S Tobata
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 39 (10) 3611 - 3619 0013-936X 2005/05 [Peer-reviewed]
     Scientific journal 
    The present study examines the effects of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) on hepatic cytochromes P450 (CYP) in the wild population of common cormorants from Lake Biwa, Japan, and discusses functional roles of CYP1A in terms of correlation analysis between tissue concentrations of individual congeners and expression levels of CYP1A. Levels of alkoxyresorufin (methoxy-, ethoxy-, pentoxy-, and benzyloxyresorufin) O-dealkylase activities and a protein cross-reacted with anti-rat CYP1A1 polyclonal antibodies showed significant positive correlations with total 2,3,7,8-tetra chlorodibenzo-p-dioxin toxic equivalents (TEQs) or TEQs for most individual congeners in the liver of cormorants, suggesting induction of CYP1A-like protein by these chemicals. In contrast, TEQs for lower chlorinated congeners, 2,3,7,8-T4CDF and PCB77, showed relatively low correlations with the expression level of CYP1A-like protein. Concentrations of 2,3,7,8-T4CDF and PCB77 normalized to a relatively recalcitrant congener, PCB169, were negatively correlated with the CYP1A-like protein level. These results indicate preferential metabolism of those congeners by CYP1A-like protein that was induced by TEQs. Concentration ratios of liver to pectoral muscle for certain congeners significantly increased with an elevation of the CYP1A-like protein level. Comparing the results in the present study with those of previous studies using rodents treated with certain dioxin-like congeners, these congeners in the liver may be sequestered by CYP1A. Levels of cross-reactive proteins with anti-rat CYP2B1, CYP2C6, and CYP3A2 polyclonal antibodies correlated with neither TEQs nor liver/muscle concentration ratios of congeners. We conclude that the potential for CYP1A induction, and metabolism and sequestration of dioxin-like compounds by CYP1A, may be a critical factor for assessing the ecological risk in wild avian species.
  • M Kobayashi, Y Kashida, K Yoneda, H Iwata, M Watanabe, S Tanabe, H Fukatsu, N Machida, K Mitsumori
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 48 (3) 424 - 432 0090-4341 2005/04 [Peer-reviewed]
     Scientific journal 
    Wild jungle crows (Corvus macrorhynchos) captured from three different areas of Tokyo were examined to evaluate environmental contamination of dioxins. In addition to the pathologic examination of their whole body, accumulation of dioxins, mRNA expression of the aryl hydrocarbon receptor (AhR), and pentoxyresorufin-O-depenthylase (PROD) activity in the liver were determined. Marked histopathologic changes were observed in the thyroid glands, especially in the crows from the urban downtown area. Levels of dioxins and their toxic equivalents (TEQs) and AhR mRNA expression in the livers of the crows from the urban area were higher than those from the suburban area. There was a high correlation between the levels of TEQs and PROD activity. The results of the present study demonstrated that jungle crows possess AhR-mediated toxicologic pathways similar to those of mammals and suggest the possibility that the thyroidal changes observed in the adult crows from the urban areas are one of the toxic manifestations resulting from exposure to dioxins and other environmental chemicals.
  • DH Nam, Y Anan, T Ikemoto, Y Okabe, EY Kim, A Subramanian, K Saeki, S Tanabe
    ENVIRONMENTAL POLLUTION 134 (3) 503 - 514 0269-7491 2005/04 [Peer-reviewed]
     Scientific journal 
    This study is to elucidate the specific accumulation of 20 trace elements in tissues/organs of great cormorants from two different colonies (Lake Biwa and Mie) in Japan. In the body distribution of trace elements, some elements revealed tissue-specific accumulation such as most of the burden of Mo, Ag and Cd in liver, Tl and Cd in kidney, Cu, Rb and Cs in muscle, and V, Sr and Ba in bone. Gender-related variation was not observed in both populations for most of the trace eleirients, except for higher hepatic Sr in males from Lake Biwa. Hepatic V, muscular Hg and Tl, and Cd in liver, kidney and muscle increased with growth. Comparison of trace element levels in tissues between the two colonies showed that Cr, Rb, Sr, Cd, Cs, Ba and Tl levels were higher in Lake Biwa than in Mie, whereas Zn, Co and Hg in Mie samples were greater than Lake Biwa. Variations of elemental levels in stomach contents also showed similar patterns, thus, showing that dietary sources tended to be the main factor for these regional variations. Toxic Hg and Cd concentrations in the liver of cormorants from the two colonies were lower than those from other areas, implying relatively low exposure to these metals in the present study sites. Concentrations of V, Co, Ag, Cd, Cs, Hg, Tl, Pb and Bi in liver remained more or less at the same level between 1993 and 2003, while hepatic Cr, Mn, Cu, Zn, Se, Rb, Sr and Ba showed apparent decrease, which might be related to the biological factors. (C) 2004 Elsevier Ltd. All rights reserved.
  • T Agusa, T Kunito, H Iwata, Monirith, I, TS Tana, A Subramanian, S Tanabe
    ENVIRONMENTAL POLLUTION 134 (1) 79 - 86 0269-7491 2005/03 [Peer-reviewed]
     Scientific journal 
    Mercury (Hg) concentrations in human hair and fish samples from Phnom Penh, Kien Svay, Tomnup Rolork and Batrong, Cambodia, collected in November 1999 and December 2000 were determined to understand the status of contamination, and age-and sex-dependent accumulation in humans and to assess the intake of mercury via fish consumption. Mercury concentrations in human hair ranged from 0.54 to 190 mug/g dry wt. About 3% of the samples contained Hg levels exceeding the no observed adverse effects level (NOAEL) of WHO (50 mug/g) and the levels in some hair samples of women also exceeded the NOAEL (10 mug/g) associated with fetus neurotoxicity. A weak but significant positive correlation was observed between age and Hg levels in hair of residents. Mercury concentrations in muscle of marine and freshwater fish from Cambodia ranged from <0.01 to 0.96 mug/g wet wt. Mercury intake rates were estimated on the basis of the Hg content in fish and daily fish consumption. Three samples of marine fish including sharp-tooth snapper and obtuse barracuda, and one sample of sharp-tooth snapper exceeded the guidelines by US EPA and by Joint FAO/WHO Expert Committee on Food Additives (JECFA), respectively, which indicates that some fish specimens examined (9% and 3% for US EPA and JECFA guidelines, respectively) were hazardous for consumption at the ingestion rate of Cambodian people (32.6 g/day). It is suggested that fish is probably the main source of Hg for Cambodian people. However, extremely high Hg concentrations were observed in some individuals and could not be explained by Hg intake from fish consumption, indicating some other contamination sources of Hg in Cambodia. (C) 2004 Elsevier Ltd. All rights reserved.
  • Sudaryanto, A, Takahashi, S, Iwata, H, Tanabe, S, Muchtar, M, Razak, H
    Marine Pollution Bulletin 50 (2) 226 - 235 2005/02 [Peer-reviewed]
  • R Murai, S Takahashi, S Tanabe, Takeuchi, I
    MARINE POLLUTION BULLETIN 51 (8-12) 940 - 949 0025-326X 2005 [Peer-reviewed]
     Scientific journal 
    Restrictions on the use of tributyltin (TBT) in aquaculture and on boats in coastal regions, except for ocean-going vessels, have been in place in Japan since 1990 due to the strong toxic effects of TBT on marine organisms. However, TBT pollution along the Japanese coasts has been reported after this legislation was enacted. In order to elucidate the present status of contamination by butyltin (BT) compounds, we measured the levels of BTs [monobutyltin (MBT), dibutyltin (DBT) and TBT] in seawater and Caprella spp. samples obtained from the western part of Seto Inland Sea, Uwa Sea and Uranouchi Bay in western Japan during March to September, 2001. Butyltins were detected in more than 90% of the seawater samples (n = 59), with average concentrations of 8.2 +/- 9.2 (SID) ng MBT L-1, 3.3 +/- 3.0 ng DBT L-1 and 9.0 +/- 7.0 ng TBT L-1. Among 41 stations situated on coastal lines, a sufficient number of Caprella organisms for chemical analysis could be collected from only 16 stations. The butyltin concentrations in seawater and Caprella samples from Uwa Sea and Uranouchi Bay, in which the dominant industry in both waters is aquaculture, showed significantly higher than or no significant differences from those samples from the western part of Seto Inland Sea, a major heavy-industry area in Japan. As the TBT concentration in seawater increased, the number of Caprella organisms collected decreased. The mean TBT concentration among the seawater samples was above the estimated lowest observable effect concentration (LOEC) that reduces the survival rate of Caprella dandevskii. Thus, the present study indicates that TBT is still a potential ecological hazard to the survival of marine invertebrates inhabiting coasts along western Japan, even I I years after the partial ban on TBT usage was implemented. (c) 2005 Elsevier Ltd. All rights reserved.
  • T Agusa, T Kunito, G Yasunaga, H Iwata, A Subramanian, A Ismail, S Tanabe
    MARINE POLLUTION BULLETIN 51 (8-12) 896 - 911 0025-326X 2005 [Peer-reviewed]
     Scientific journal 
    Concentrations of trace elements (V, Cr, Mn, Co, Cu, Zn, Ga, Se, Rb, Sr, Mo, Ag, Cd, Sn, Sb, Cs, Ba, Hg, Tl, Pb and Bi) were determined in muscle and liver of 12 species of marine fish collected from coastal areas in Malaysia. Levels of V, Cr, Mn, Co, Cu, Zn, Ga, Sr, Mo, Ag, Cd, Sri, Ba and Pb in liver were higher than those in muscle, whereas Rb and Cs concentrations showed the opposite trend. Positive correlations between concentrations in liver and muscle were observed for all the trace elements except Cu and Sn. Copper, Zn, Se, Ag, Cd, Cs and Hg concentrations in bigeye scads from the east coast of the Peninsular Malaysia were higher than those from the west, whereas V showed the opposite trend. The high concentration of V in the west coast might indicate oil contamination in the Strait of Malacca. To evaluate the health risk to Malaysian population through consumption of fish, intake rates of trace elements were estimated on the basis of the concentrations of trace elements in muscle of fish and daily fish consumption. Some specimens of the marine fish had Hg levels higher than the guideline value by US Environmental Protection Agency (EPA), indicating that consumption of these fish at the present rate may be hazardous to Malaysian people. To our knowledge, this is the first study on multielemental accumulation in marine fish from the Malaysian coast. (c) 2005 Elsevier Ltd. All rights reserved.
  • T Ikemoto, T Kunito, S Tanabe, M Tsurumi, F Sato, N Oka
    MARINE POLLUTION BULLETIN 51 (8-12) 889 - 895 0025-326X 2005 [Peer-reviewed]
     Scientific journal 
    Concentrations of 18 trace elements (V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Hg, Tl and Ph) were determined in abandoned eggs of short-tailed albatrosses and abandoned eggs and blood of black-footed albatrosses from Torishima Island, Japan in 2002. Mercury concentration was highest among the toxic elements in egg content of both the two species. In some egg contents of black-footed albatrosses, Hg concentrations were higher than the threshold level that may cause decreased hatchability and aberrant nesting behavior in some avian species. Concentrations of Cd in egg content and Ba in egg content and shell increased with an increase in egg breadth/length ratio, whereas Hg in egg content showed an opposite trend in black-footed albatrosses. Since egg breadth/length ratio is known to increase with the age of mother bird, this result may imply that concentrations of these elements in eggs vary with age of mother bird. In blood of black-footed albatross chicks, concentration of Hg was highest among the toxic elements and the Hg concentration showed an increase in the later growth stages. In contrast, concentration of Sr in blood decreased with growth stage. Since the behaviour of Sr is similar to that of Ca in animals, it is conceivable that Sr was used along with Ca for the formation of bone. (c) 2005 Elsevier Ltd. All rights reserved.
  • Y Anan, T Kunito, S Tanabe, Mitrofanov, I, DG Aubrey
    MARINE POLLUTION BULLETIN 51 (8-12) 882 - 888 0025-326X 2005 [Peer-reviewed]
     Scientific journal 
    Concentrations of 13 trace elements (V, Mn, Cr, Co, Cu, Zn, Se, Mo, Ag, Cd, Hg, Tl and Pb) were determined in muscle of bony fishes collected from coastal areas of the Caspian Sea (Kazakhstan, Azerbaijan, Turkmenistan and Iran). In all the fishes, Zn concentration was highest, followed by Cu, Se, Mn and Co, while levels of toxic elements (Ag, Cd, Cd, Tl and Pb) were relatively low. Concentrations of several elements were significantly varied between the species in each sampling area. For most of the trace elements examined, the concentrations decreased significantly with body weight of fishes. In contrast, a positive correlation with body weight was found for Co, Se and Ph concentrations in one fish species, and Hg in 2 fish species. Geographical difference in the concentrations of trace elements was examined using the Caspian roach collected from five stations of Iranian coastal waters. The concentrations of Co, Mo, Ag, Cd and Tl were higher in fishes from western stations than those from eastern stations, whereas the opposite trend was observed for Hg, indicating that local sources of trace metal pollution may be present in the Iranian coastal areas of the Caspian Sea. Levels of trace elements in Caspian fishes were relatively low in comparison to those of other regions, but Zn and Hg levels in some specimens exceeded the guideline values for food. (c) 2005 Elsevier Ltd. All rights reserved.
  • R Kubota, T Kunito, J Fujihara, S Tanabe, J Yang, N Miyazaki
    MARINE POLLUTION BULLETIN 51 (8-12) 845 - 849 0025-326X 2005 [Peer-reviewed]
     Scientific journal 
    Concentrations of total arsenic and individual arsenic compounds were determined in liver, muscle, kidney and blubber of mother and fetus of Dall's porpoises collected from off Sanriku, Japan, in the year 2000 to characterize the placental transfer of arsenic to fetus in cetaceans. Arsenic was detected in all the tissues of Dall's porpoises. Total arsenic concentrations in liver, kidney, muscle and blubber were 0.76, 0.69, 0.35 and 0.55 mu g/g wet wt, respectively, for mother and 0.28, 0.23, 0.26 and 0.07 mu g/g wet wt, respectively, for fetus. In all the tissues, concentrations of total arsenic in mother Dall's porpoise were higher than in fetus. Arsenic speciation revealed that arsenobetaine was the major arsenic compound in liver, kidney and muscle of both mother and fetus. The percentage of arsenobetaine to total arsenic ranged from 76.0 to 91.0% in the tissues. Dimethylarsinic acid, arsenocholine, methylarsonic acid and an unidentified arsenic compound were also detected in tissues of both mother and fetus as minor constituents, whereas tetramethylarsonium ion was not detected in tissues of the fetus. These results suggest that arsenobetaine, dimethylarsinic acid, arsenocholine and methylarsonic acid are transferable from mother to fetus in Dall's porpoises. To our knowledge, this is the first report on placental transfer of arsenic compounds to fetus in marine mammals. (c) 2005 Elsevier Ltd. All rights reserved.
  • S Niimi, MX Watanabe, EY Kim, H Iwata, G Yasunaga, Y Fujise, S Tanabe
    MARINE POLLUTION BULLETIN 51 (8-12) 784 - 793 0025-326X 2005 [Peer-reviewed]
     Scientific journal 
    This study presents full-length cDNA sequences of CYP1A1 and 1A2, in common minke whale (Balaenoptera acutorostrata) from the North Pacific. Both CYP1A1 and CYP1A2 cDNAs had an open reading frame of 516 amino acid residues, and predicted molecular masses were 58.3 kDa and 58.1 kDa, respectively. The deduced full-length amino acid sequence of CYP1A1 revealed higher identities with those of sheep (86%) and pig (87%), and that of CYP1A2 was most closely related to human (82%) and monkey CYP1A2 (82%) among species from which CYP1A2 has been isolated so far. Differences in certain conserved and functional amino acid residues of CYP1A1 and 1A2 between common minke whale and other mammalian species indicate the possibility of their specific metabolic function. Concentrations of organochlorine compounds (OCs) including PCBs and DDTs analyzed in common minke whale liver showed no significant correlation with hepatic mRNA expression levels of CYP1A1 and CYP1A2, indicating no induction of these enzymes by such OCs. (c) 2005 Elsevier Ltd. All rights reserved.
  • DH Nam, Y Anan, T Ikemoto, EY Kim, S Tanabe
    MARINE POLLUTION BULLETIN 51 (8-12) 750 - 756 0025-326X 2005 [Peer-reviewed]
     Scientific journal 
    This study investigated the subcellular distribution of Cu, Zn, Cd and Ag in liver of mallard (Anas platyrhynchos), spot-billed duck (A. poecilorhyncha) and great cormorant (Phalacrocorax carbo) to better understand metal fractionation and dynamics in avian liver. Most of the total Cu, Zn, Cd and Ag were present in hepatocytosol, and their concentrations increased with total hepatic levels in all the three avian species. Copper, Zn and Cd in hepatocytosol were present mostly in metallothionein fractions (MTs), and Cu and Cd contents in this fraction were positively correlated with hepatocytosol levels in all the species. Silver was observed mostly in both high-molecular weight and NIT fractions in hepatocytosol in mallard and great cormorant, whereas it was present in both low-molecular weight and NIT fractions in spot-billed duck, suggesting that distribution of Ag in the hepatocytosol was species-specific. The elution profile of metals in MT fractions revealed six metallic peaks in mallard and spot-billed duck, and three peaks in great cormorant, implying the presence of multiple NIT isoforms in the liver of these avian species. The present study demonstrated that MTs are closely associated with metal regulation, especially Cu and Cd, in these three aquatic birds. (c) 2005 Published by Elsevier Ltd.
  • K Ramu, N Kajiwara, S Tanabe, PKS Lam, TA Jefferson
    MARINE POLLUTION BULLETIN 51 (8-12) 669 - 676 0025-326X 2005 [Peer-reviewed]
     Scientific journal 
    Polybrominated diphenyl ethers (PBDEs) and organochlorine compounds (OCs) were determined in the blubber, liver and kidney of Indo-Pacific humpback dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides) stranded in Hong Kong coastal waters during 1995-2001. Among the organohalogen compounds analyzed, DDTs were the most dominant contaminants with concentrations ranging from 9.9 to 470 mu g/g lipid wt. PBDEs in Hong Kong cetaceans, which are reported for the first time, were detected in all the samples with values ranging from 0.23 to 6.0 mu g/g lipid wt., with a predominance of BDE-47. Results from this study suggest PBDEs should be classified as priority pollutants in Asia. Higher concentrations were found in humpback dolphins than in finless porpoises, and this was attributed mainly to differences in habitat. Elevated residues of PCBs and DDTs in some cetaceans suggest these species may be at risk. (c) 2005 Elsevier Ltd. All rights reserved.
  • 今西克也, 川上 学, 島田あずさ, 木村義孝, 近石一弘, 村上雅志, 梶原夏子, 山田 格, 田辺信介
    環境化学 15 (2) 429 - 443 2005 [Peer-reviewed]
  • 上田浩三, 岩本智史, 梅村省三, 長屋喜一, 岩田久人, 田辺信介
    環境化学 15 (2) 311 - 320 2005 [Peer-reviewed]
  • T Arai, T Ikemoto, A Hokura, Y Terada, T Kunito, S Tanabe, Nakai, I
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 38 (24) 6468 - 6474 0013-936X 2004/12 [Peer-reviewed]
     Scientific journal 
    Marine mammals and seabirds tend to exhibit high accumulations of mercury, cadmium, and selenium in their livers and kidneys. In this study, chemical forms of mercury, cadmium, and selenium accumulated in the livers and kidneys of northern fur seal (Callorhinus ursinus), Bisso's dolphin (Grampusgriseus),and black-footed albatross (Diomedea nigripes) were studied by extended X-ray absorption fine structure (EXAFS) spectroscopy to reveal the detoxification mechanisms of these metals. It was found that mercury and selenium exist in the form of HgSe in the liver of northern fur seal. Mercury levels were found to be higher than those of Se, based on their molar ratio, in black-footed albatross. XAFS analysis disclosed an existence of chalcogenide containing both Hg-Se and the Hg-S bonds, suggesting the existence of a solid solution Hg(Se, S) as granules in black-footed albatross. In contrast, Cd concentrations in the kidney were higher than those in the liver for northern fur seal, black-footed albatross, and Risso's dolphin. It was found that Cd was bound to sulfur, which was probably derived from the metallothionein, The Cd-O bond was observed in the tissues of northern fur seal.
  • T Agusa, T Kunito, S Tanabe, M Pourkazemi, DG Aubrey
    MARINE POLLUTION BULLETIN 49 (9-10) 789 - 800 0025-326X 2004/11 [Peer-reviewed]
     Scientific journal 
    Concentrations of 21 trace elements were determined in muscle of beluga (Huso huso), Persian sturgeon (Acipenser persicus), Russian sturgeon (Acipenser gueldenstaedtii), ship sturgeon (Acipenser nudiventris) and stellate sturgeon (Acipenser stellatus) collected from coastal regions of Azerbaijan, Iran, Kazakhstan and Turkmenistan, surrounding the Caspian Sea during 2000-2001. Concentrations of Mn, Co, Cu, Mo, Sn, Hg, Ph and Bi in the muscle were apparently different among the five species of sturgeons. Especially, beluga showed the highest concentrations of Hg, Pb and Mn in all the five species. In addition, more than half of the individuals of beluga exceeded the guideline level (0.3 mug/g wet wt.) of Hg for food in UK. However, V, Cr, Zn, Ga, Rb, Sr and Ba concentrations were similar among five sturgeons. Growth-dependent increase in Hg in beluga, Cu in Persian sturgeon, and Zn in Russian sturgeon were observed, whereas V, Mn, Co, Cu, Ga, Sr, Mo, Sn, Hg and Bi concentrations in Persian sturgeon, Ph in ship sturgeon, and Cr, Mn, and Rb in stellate sturgeon were negatively correlated with body length. All species of sturgeon in Azerbaijan showed the highest concentration of Sr and the lowest concentration of Rb, while the five sturgeons from Iran showed opposite trends. Concentration of V, which is present in oil, in sturgeons in the Caspian Sea was considerably lower than that of fish from Kuwait, but was comparable to that of Cambodia and the Gulf and Gulf of Oman. To our knowledge, this study provides the first extensive data on multielemental accumulation in sturgeons of the Caspian Sea. (C) 2004 Elsevier Ltd. All rights reserved.
  • Takeuchi, I, S Takahashi, S Tanabe
    JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM 84 (5) 911 - 918 0025-3154 2004/10 [Peer-reviewed]
     Scientific journal 
    Caprella spp. (Crustacea: Amphipoda) inhabiting the Satgassum algal community in Otsuchi Bay near unpopulated areas of northern Japan, were collected froth 1994 to 2001 and subjected to analysis of butyltin (BT) concentrations. The period from 1994 to 2001 corresponds to four to 11 years after legislation limiting the use of tributyltin (TBT) on small boats and aquaculture facilities was passed in Japan. Butyltin compounds including TBT, dibutyltin (DBT) and monobutyltin (MBT) were detected in all samples of Capzella spp., although the three BTs were not detected in seawater samples collected from the same area between 1997 and 1999. The concentration of total BTs (BTs=MBT+DBT+TBI') in Caprella spp. significantly decreased froth 84 ng BTs/g wet wt in 1994 to 7.4 ng/g wet wt in 2001. The concentrations of BTs in Caprella spp., which have a high bioconcentration factor for TBh are thought to reflect the average concentrations of BTs in the surrounding seawater in the previous few months. The half-life of BTs and TB 1, in Capzella spp. was 2.38 years and 2.07 years, respectively, which are less than half of that of TBT in seawater based on the national survey of The Ministry of the Environment, Japan. Illegal usage of TBT near the studied area may have decreased due to monitoring of BTs.
  • T Ikemoto, T Kunito, H Tanaka, N Baba, N Miyazaki, S Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 47 (3) 402 - 413 0090-4341 2004/10 [Peer-reviewed]
     Scientific journal 
    Subcellular distribution of mercury, selenium, silver, copper, zinc, and cadmium was determined in the liver of northern fur seals (Callorhinus ursinus), black-footed albatrosses (Diomedea nigripes), and Dall's porpoises (Phocoenoides dalli). Mercury, selenium, and silver were preferentially accumulated in nuclear, lysosomal, and mitochondrial fraction with an increase in their hepatic concentrations, whereas copper, zinc, and cadmium were accumulated mainly in cytosol with an increase in the hepatic concentrations for all three species. To gain insight into the existing state of the metals, they were extracted with four extractants-sodium dodecylsulfate (SDS); 2-mercaptoethanol; 2-mercaptoethanol + guanidinium thiocyanate; and copper sulfate (CuSO4)-at several concentrations from nuclear, lysosomal, and mitochondrial fraction in liver from a specimen of northern fur seal. Extraction efficiencies of the metals for 2-mercaptoethanol + guanidinium thiocyanate and CuSO4 were much higher than those for SDS and 2-mercaptoethanol. Also, for all individuals of the three species, metals were extracted by the three extractants-2% SDS; 0.25 mol/L 2-mercaptoethanol + 5 mol/L guanidinium thiocyanate; and 0.1 mol/L CuSO4-from nuclear, lysosomal, and mitochondrial fraction of liver. In the northern fur seals with higher concentration of mercury, the molar ratio of selenium to mercury approached unity in the nonextractable fraction of 0.25 mol/L 2-mercaptoethanol + 5 mol/L guanidinium thiocyanate, suggesting the possible formation of mercuric selenide (HgSe) with increasing hepatic concentration. Because the nonextractable content of mercury and its distribution were larger for black-footed albatross than those for the other two species, it was suggested that the black-footed albatross has a stronger ability to form a stable compound(s) of mercury in the liver. It is notable that the existing state of silver was similar to that of mercury as judged by their subcellular distribution and the extraction tests, suggesting that silver also interacted with selenium in the liver of marine animals used in this study.
  • T Kunito, S Nakamura, T Ikemoto, Y Anan, R Kubota, S Tanabe, FCW Rosas, G Fillmann, JW Readman
    MARINE POLLUTION BULLETIN 49 (7-8) 574 - 587 0025-326X 2004/10 [Peer-reviewed]
     Scientific journal 
    Concentrations of trace elements (V, Cr, Mn, Fe, Co, Cu, Zn, Ga, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, T-Hg, Org-Hg, Tl and Pb) were determined in liver samples of estuarine dolphin (Sotalia guianensis; n = 20), Franciscana dolphin (Pontoporia blainvillei; n = 23), Atlantic spotted dolphin (Stenella frontalis; n = 2), common dolphin (Delphinus capensis; n = 1) and striped dolphin (Stenella coeruleoalba; n = 1) incidentally caught along the coast of Sao Paulo State and Parana State, Brazil, from 1997 to 1999. The hepatic concentrations of trace elements in the Brazilian cetaceans were comparable to the data available in literature on marine mammals from Northern Hemisphere. Concentrations of V, Se, Mo, Cd, T-Hg and Org-Hg increased with increasing age in liver of both estuarine and Franciscana dolphins. Very high concentrations of Cu (range, 262-1970 mug/g dry wt.) and Zn (range, 242-369 mug/g dry wt.) were observed in liver of sucklings of estuarine dolphin. Hepatic concentrations of V, Se, T-Hg, Org-Hg and Pb were significantly higher in estuarine dolphin, whereas Franciscana dolphin showed higher concentrations of Mn, Co, As and Rb. Ratio of Org-Hg to T-Hg in liver was significantly higher in Franciscana dolphin than estuarine dolphin, suggesting that demethylation ability of methyl Hg might be lower in liver of Franciscana than estuarine dolphins. High hepatic concentrations of Ag were found in some specimens of Franciscana dolphin (maximum, 20 mug/g dry wt.), and 17% of Franciscana showed higher concentrations of Ag than Hg. These samples with high Ag concentration also exhibited elevated hepatic Se concentration, implying that Ag might be detoxified by Se in the liver. Higher correlation coefficient between (Hg + 0.5 Ag) and Se than between Hg and Se and the large distribution of Ag in non-soluble fraction in nuclear and mitochondrial fraction of the liver also suggests that Ag might be detoxified by Se via formation of Ag2Se in the liver of Franciscana dolphin. (C) 2004 Elsevier Ltd. All rights reserved.
  • T Kunisue, M Watanabe, H Iwata, A Subramanian, Monirith, I, TB Minh, R Baburajendran, TS Tana, PH Viet, M Prudente, S Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 47 (3) 414 - 426 0090-4341 2004/10 [Peer-reviewed]
     Scientific journal 
    In this study, concentrations of dioxins and related compounds (DRCs)-such as polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls-were found in human breast milk from women living near dumping sites of municipal waste and reference sites in India, Cambodia, Vietnam, and the Philippines during 1999 to 2000. DRCs were detected in all human breast milk samples analyzed, demonstrating that residents in these Asian developing countries have been exposed to these contaminants. In India, the concentrations of DRCs in human breast milk from women living near the investigated dumping site were notably higher than those from women living near reference sites and from women in other Asian developing countries. Toxic equivalent quantity (TEQ) levels of DRCs were comparable with or higher than those reported in the general populations of developed countries since 1990. In contrast, levels of these contaminants in human breast milk in women from Cambodia and Vietnam were not significantly different between milk from women living near the dumping and reference sites. These results indicate that significant pollution sources for DRCs are present in Indian dumping sites and that residents there have been exposed to relatively higher levels of these contaminants. TEQ levels in human breast milk from the dumping site in India tended to decrease with an increase in the number of previous deliveries by mothers, whereas no significant relationship was observed in Cambodia, Vietnam, or the Philippines. This suggests that mothers who have been exposed to relatively high levels of DRCs transfer greater amounts of these contaminants to the first infant than later ones through breast-feeding, which in turn implies that the first children of these mothers might be at higher risk from DRCs. When the residue levels of DRCs in bovine milk collected from the Indian dumping site and reference sites were examined, TEQ levels in bovine milk from the dumping suggests that bovine milk is a potential source of DRCs for residents living near the dumping site in India. To our knowledge, this is the first comprehensive study on exposure to DRCs of residents living in proximity to open dumping sites of municipal waste in Asian developing countries.
  • K Kannan, N Kajiwara, BJ Le Boeuf, S Tanabe
    ENVIRONMENTAL POLLUTION 131 (3) 425 - 434 0269-7491 2004/10 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated biphenyls (PCBs), DDTs, chlordanes, HCHs, hexachlorobenzene (HCB), dieldrin, heptachlor epoxide, tris(4-chlorophenyl)methane (TCPMe), and tris(4-chlorophenyl)methanol (TCPMOH) were measured in the blubber of California sea lions (Zalophus californianus) collected in 2000. DDTs were the most predominant contaminants, followed by PCBs, chlordanes, TCPMe, HCHs, TCPMOH, dieldrin, and heptachlor epoxide. Concentrations of PCBs and DDTs varied from a few mug/g to several hundreds of mug/g on a lipid weight basis. Concentrations of DDTs have declined by an order of magnitude over the last three decades in California sea lions; nevertheless, the measured concentrations of PCBs and DDTs in California sea lions are still some of the highest values reported for marine mammals in recent years. Concentrations of organochlorines were highly correlated with one another. Concentrations of PCBs and DDTs in the blubber of gray whale, humpback whale, northern elephant seal, and harbor seal, and in the adipose fat of sea otter, were lower than the levels found in California sea lions, and were in the range of a few to several mug/g on a lipid weight basis. (C) 2004 Elsevier Ltd. All rights reserved.
  • T Kunisue, M Someya, F Kayama, Y Jin, S Tanabe
    ENVIRONMENTAL POLLUTION 131 (3) 381 - 392 0269-7491 2004/10 [Peer-reviewed]
     Scientific journal 
    The present study determined the concentrations of organochlorines (OCs) such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB) and tris(4-chlorophenyl)methane (TCPMe) in human breast milk collected from primiparae in Dalian and Shenyang, northeastern China during 2002. In addition, dioxins and related compounds in pooled samples of human breast milk from Dalian and Shenyang were also analyzed. OCs were detected in all the human breast milk samples analyzed in this study. The predominant contaminants in human breast milk were HCHs, DDTs and HCB, and the levels were relatively higher than those in other countries. On the other hand, concentrations of dioxins and related compounds, PCBs, and CHLs were relatively low. Concentrations of OCs in human breast milk from Dalian, which is located along the coast of Bo Hai Strait, were significantly higher than those from Shenyang, implying that the residents in Dalian might be mainly exposed to these contaminants from seafood. When the relationship between concentrations of OCs in human breast milk and age of primiparae was examined, no significant correlation was observed. This might be caused by the limited sample numbers and narrow range of mother's age and/or recent ban of DDT and HCH production and use. Significant correlation between concentrations of TCPMe and DDTs in human breast milk suggested that technical DDT might be a source of TCPMe in the Chinese population. When daily intakes of DDTs and HCHs to infants through human breast milk were estimated, human breast milk from Dalian showed significantly higher contribution than Shenyang, implying that infants in Dalian might be at higher risk by these contaminants. (C) 2004 Elsevier Ltd. All rights reserved.
  • T Ikemoto, T Kunito, Y Anan, H Tanaka, N Baba, N Miyazaki, S Tanabe
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 23 (8) 2008 - 2016 0730-7268 2004/08 [Peer-reviewed]
     Scientific journal 
    Distribution of Cu, Zn, Cd, Ag, Hg, and Se were determined in hepatocytosol of northern fur seals (Callorhinus ursinus), black-footed albatrosses (Diomedea nigripes), and Dall's porpoises (Phocoenoides dalli). Copper, Zn, and Cd were accumulated preferentially in metallothionein (MT) fraction and their contents in MT fraction increased with the amounts in the hepatocytosol. Silver was bound to both high-molecular-weight substances (HMWS) and MT in the hepatocytosol for all three species, whereas the distribution of Ag in the cytosol was different among the three species. In northern fur seals, Ag mainly was bound to MT, whereas it mainly was associated with HMWS in Dall's porpoises. In contrast, Ag was distributed almost equally in both HMWS and MT for black-footed albatrosses. Mercury content in HMWS and Se content in HMWS and low-molecular-weight substances (LMWS) increased with their contents in hepatocytosol for all the three species. A significant positive correlation was found between Se and Hg contents in high-molecular weight (HMW) fraction in cytosol. The molar ratio of Hg and Se was close to unity in HMW fraction of the specimens with high Hg concentration in cytosol, implying that the Hg-Se complex was bound to the HMWS. Analysis of metals in the hepatocytosol by high-performance liquid chromatography/inductively coupled plasma-mass spectrometry (HPLC/ICP-MS) suggests that multiple isoforms of MT are present in hepatocytosol of the three species and that the metal profiles in hepatocytosols are different among the species. To our knowledge, this is the first report on the. association of Ag with HMWS and NIT in hepatocytosol of marine mammals and seabirds. Also, distribution and interaction of Hg and Se were investigated for the first time in hepatocytosol of the higher trophic marine animals.
  • EY Kim, H Iwata, Y Fujise, S Tanabe
    MARINE ENVIRONMENTAL RESEARCH 58 (2-5) 495 - 498 0141-1136 2004/08 [Peer-reviewed]
     Scientific journal 
    The contaminant-induced cytochrome P450 (CYP) members in minke whale (Balaenoptera acutorostrata) can be potential biomarkers of the contaminant exposure and toxic effects. In this study, we constructed a cDNA library from the liver of minke whale from the North Pacific, and further screened a total of 6930 clones randomly selected in the library for the isolation of cDNA clones encoding novel members of CYP superfamily. The screening revealed the isolation of six novel CYP cDNA clones that are classified into CYP1A, CYP2C, CYP2E, CYP3A, CYP4, and CYP4A subfamilies. The BLAST homology search using the partial cDNA fragments of four CYP subfamilies (CYP1A, CYP2C, CYP2E and CYP4A) demonstrated that the minke whale CYPs were most closely related to pig CYPs (81-91%). Identification of multiple CYP genes in marine mammal species such as minke whale will provide new insights into the metabolic or toxicological functions of individual CYP members. (C) 2004 Elsevier Ltd. All rights reserved.
  • T Yasui, EY Kim, H Iwata, S Tanabe
    MARINE ENVIRONMENTAL RESEARCH 58 (2-5) 113 - 118 0141-1136 2004/08 [Peer-reviewed]
     Scientific journal 
    The toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and its related planar halogenated aromatic hydrocarbons (PHAHs) are mediated by the aryl hydrocarbon receptor (AHR). To investigate the potential sensitivity to PHAHs and the evolutional diversity of AHR in aquatic birds, AHR cDNAs were initially cloned and sequenced from the livers of a black-footed albatross (Diomedea nigripes) and a common cormorant (Phalacrocorax carho). In this study, we report the identification of two distinct AHR paralog genes in these species. The two full-length AHR cDNAs from albatross were highly divergent (33% overall amino acid identity, and 60% identity in the N-terminal half). Phylogenetic analysis showed that one of them belongs to the AHR1 clade and the other one to the AHR2 clade, which has been identified only from fishes, but not yet from mammals and birds. Albatross AHR1 encoded a 861-residue protein with a predicted molecular mass of 96.7 kDa, and in the case of albatross AHR2, 925 amino acids and 100.7 kDa. From cormorant liver, the full-length AHR1 cDNA and the partial AHR2 cDNA were cloned. This result strongly suggests that bird species also possess two distinct AHR genes (AHR1 and AHR2). To our knowledge, this is the first report on the presence of an AHR2-like isoform in bird species as well as in fish. (C) 2004 Elsevier Ltd. All rights reserved.
  • H Sakai, H Iwata, EY Kim, S Tanabe, N Baba
    MARINE ENVIRONMENTAL RESEARCH 58 (2-5) 107 - 111 0141-1136 2004/08 [Peer-reviewed]
     Scientific journal 
    Constitutive androstane receptor (CAR) plays a key role in the transcriptional regulation of CYP2B, 2C and 3A genes in response to phenobarbital, ortho-chlorine substituted polychlorinated biphenyls (PCBs) and sex steroids in rodents and human. However, studies addressing CAR are limited to certain laboratory animals and cell lines, and there is little information on the presence of CAR and its physiological and contaminant-related functions in wildlife. While aquatic mammals including seal species are at the top of food chain and highly contaminated by xenochemicals such as PCBs, induction of CYP2/3 subfamilies by such chemical exposure and their regulatory mechanisms have not yet been established in these animals. To investigate mechanisms of CAR-CYP's signaling pathways in aquatic mammals, we initially attempted to isolate CAR cDNA in the liver of northern fur seals (Callorhinus ursinus) from off-Sanriku, Japan. The full-length CAR cDNA had an open reading frame of 1047 bp that encodes a protein containing 348 amino acids. Comparison of the amino acid sequence of CAR from the fur seal with those from other mammalian species showed high identities with CARs from human (83%), monkey (82%), rat (73%) and mouse (73%), revealing a conservation of CAR among the mammalian species. Phylogenetic analysis demonstrated that the fur seal CAR was classified into CAR clade and not into PXR/BXR or VDR clade, suggesting the CARs would be conserved among, divergent mammals including aquatic species. With our concomitant paper, where CAR cDNA isolation from the liver of Baikal seal is reported (Iwata et al., in preparation), to our knowledge, this is the first study on the identification of CAR cDNA from wildlife species. (C) 2004 Elsevier Ltd. All rights reserved.
  • A Sudaryanto, S Takahashi, H Iwata, S Tanabe, A Ismail
    ENVIRONMENTAL POLLUTION 130 (3) 347 - 358 0269-7491 2004/08 [Peer-reviewed]
     Scientific journal 
    Concentration of butyltin compounds (BTs), including tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) and total tin (SigmaSn) were determined in green mussel (Perna viridis), 10 species Of Muscle fish and sediment from coastal waters of Malaysia. BTs were detected in all these samples ranging from 3.6 to 900 ng/g wet wt., 3.6 to 210 ng/g wet wt., and 18 to 1400 ng/g dry wt. for mussels, fish and sediments, respectively. The concentrations of BTs in several locations of this study were comparable with the reported values from some developed countries and highest among Asian developing nations. Considerable concentration of BTs in several locations might have ecotoxicological consequences and may cause concern to human health. The parent compound TBT was found to be highest than those of its degradation compounds, DBT and MBT, suggesting recent input of TBT to the Malaysian marine environment. Significant positive correlation (Spearman rank correlation: r(2) = 0.82, P < 0.0001) was found between BTs and SigmaSn, implying considerable anthropogenic input of butyltin compounds to total tin contamination levels. Enormous boating activities may be a major source of BTs in this country, although aquaculture activities may not be ignored. (C) 2004 Elsevier Ltd. All rights reserved.
  • A Kubota, H Iwata, S Tanabe, K Yoneda, S Tobata
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 38 (14) 3853 - 3859 0013-936X 2004/07 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) were determined in the liver and pectoral muscle of common cormorants (Phalacrocorax carbo) collected from Lake Biwa, Japan. To clarify the toxicokinetic behaviors and potential toxicities of these chemicals, the present study addresses life-stage- and tissue-specific accumulation of the congeners. Total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) were in the range of 360 to 50 000 pg/g lipid weight in the liver and 310 to 12 000 pg/g lipid weight in the pectoral muscle. Among congeners, for which toxic equivalency factors were assigned, PCB126, 2,3,4,7,8-P5CDF, and 1,2,33,8-P5CDD made a greater contribution to total TEQs in the liver. Hepatic concentrations of T-4- to H6CON, P-5- and H(6)CDFs, and Co-PCBs (except PCB77) significantly increased with growth of cormorants, leading to life-stage-related compositional changes. The concentration ratios of liver to pectoral muscle revealed preferential accumulation of higher chlorinated congeners in hepatic tissue. For most congeners, concentration ratios significantly increased with an increase in hepatic total TEQs, suggesting their con centration-dependent hepatic sequestration. These results imply the presence of hepatic binding protein(s) such as cytochrome P450, inducible by these chemicals, which may function as a binding species different from aryl hydrocarbon receptor. On the basis of these results, we conclude that the toxicokinetic behavior of each congener is life-stage-, tissue-, and concentration-dependent. TEN in wildlife populations exposed to multiple congeners with varying concentrations should be used with caution for risk assessment, even within a species.
  • N Kajiwara, D Ueno, A Takahashi, N Baba, S Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 38 (14) 3804 - 3809 0013-936X 2004/07 [Peer-reviewed]
     Scientific journal 
    The present study clearly indicated possible prolonged and chronic marine pollution by polybrominated diphenyl ethers (PBDEs) unless the international regulatory measures are reinforced substantially. Fat tissues of female northern fur seals (Callorhinus ursinus), collected at 10 time periods between 1972 and 1998 from the Pacific coast of northern Japan,were analyzed for PBDEs and organochlorine compounds (M). PCBs and DDTs were the predominant contaminants in the fur seal samples. PBDEs were detected in all the samples analyzed, the values ranging from 0.33 to 100 ng/g lipid wt. with predominance of BDE-47. The lowest PBDE levels were in the fur seals collected in 1972, with the peak concentration around 1991-1994 and then decreased to about 50% in 1997-1998. Compositions of higher brominated congeners increased since 1972, while some lower brominated congeners decreased, implying a change in the pattern of use, particularly the increased use of highly brominated diphenyl ethers during 1972-1998. In the meantime, PCB compositions in fur seals showed no temporal variation, suggesting a continuous input of PCBs into the marine environment in significant quantities. As peak concentrations of PBDEs occurred later than OCs, it is essential to follow up the patterns of PBDEs pollution that may be of great concern in the future. To our knowledge, this is the first report on the contamination by PBDEs in marine mammals from the Asia-Pacific waters.
  • H Iwata, M Watanabe, Y Okajima, S Tanabe, M Amano, N Miyazaki, EA Petrov
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 38 (13) 3505 - 3513 0013-936X 2004/07 [Peer-reviewed]
     Scientific journal 
    To assess the toxicokinetic behavior and potential toxicity of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (PCBs) in Baikal seals, congener-specific levels and tissue distribution were evaluated in the liver and blubber, and the effects of biological factors including sex and growth were assessed. Total 2,3,7,8-TCDD toxic equivalents (TEQs) were in the range of 210-920 pgTEQ/g fat wt (180-800 pgTEQ/g wet wt) in the blubber and 2907800 pgTEQ/g fat wt (10-570 pgTEQ/wet wt) in the liver. Non-ortho coplanar PCB126 was the most TEQ-contributed congener accounting for 37-59% of the total THIS in the liver. From the unique congener profiles, weak metabolic properties of Baikal seals for 2,3,7,8-TCDF and 1,2,3,7,8-P-5-CDF are suggested. Concentrations of most congeners linearly increased with age in male seals, whereas in adult females the levels revealed an age-related decline. The increasing and declining rates were congener-specific. Maternal transfer rates of 5 representative congeners from adult female to pup through lactation, which was estimated from male-female differences in the body burden, was 1.1 ngTEQ/kg/day for the first pup and decreased with every lactational epoch. The liver-blubber distribution of 1,2,3,4,7,8-H6CDD, 1,2,3,6,7,8-H6CDD, PCB81, PCB126, and PCB169 was dependent on the hepatic total TEQ, indicating hepatic sequestration by induced cytochrome P450 (CYP). These results indicate that congener profile in Baikal seals is governed by complex factors including sex, tissue concentration, binding to CYP, and rates of absorption and meta bolism/excretion.
  • J Fujihara, T Kunito, R Kubota, H Tanaka, S Tanabe
    MARINE POLLUTION BULLETIN 48 (11-12) 1153 - 1160 0025-326X 2004/06 [Peer-reviewed]
     Scientific journal
  • J Yang, T Kunito, Y Anan, S Tanabe, N Miyazaki
    MARINE POLLUTION BULLETIN 48 (11-12) 1122 - 1129 0025-326X 2004/06 [Peer-reviewed]
     Scientific journal 
    Total and subcellular hepatic Zn, Cu, Se, Mn, V, Hg, Cd, and Ag were determined in a mother-fetus pair of Dall's porpoises (Phocoenoides dalli). Except for higher fetal Cu concentration, all maternal elements were higher. Elements existed mostly in the cytosol of both animals except in the case of maternal Ag in the microsome and fetal Cu and Ag in the nuclei and mitochondria. In the maternal cytosol, Zn, Mn, Hg, and Ag were present in the high-molecular-weight substances (HMW); Se and V were present in the low-molecular-weight substances (LMW); Cu and Cd were mostly sequestered by metallothionein (MT). In the fetal cytosol, Zn, Se, Mn, Hg, Cd, and Ag were present in the HMW and V in the LMW, while Cu and Ag were mostly associated with MT. MT isoforms were characterized using the HPLC/ICP-MS. Two and four obvious peaks appeared in the maternal and fetal MT fractions, respectively. The highest elemental ion intensities were at a retention time of 7.8 min for the mother, and for the fetus the peak elemental ion intensities occurred at a retention time of 4.3 min, suggesting that different MT isoforms may be involved in elemental accumulation in maternal and fetal hepatocytosols. (C) 2003 Elsevier Ltd. All rights reserved.
  • NH Minh, M Someya, TB Minh, T Kunisue, H Iwata, M Watanabe, S Tanabe, PH Viet, BC Tuyen
    ENVIRONMENTAL POLLUTION 129 (3) 431 - 441 0269-7491 2004/06 [Peer-reviewed]
     Scientific journal 
    Despite the ban on persistent organochlorines (OCs) in most of the developed nations, their usage continued until recently in many Asian developing countries including Vietnam, for agricultural purposes and vector-borne disease eradication programs. In this study. we collected human breast milk samples from the two big cities in Vietnam: Hanoi (n = 42) and Hochiminh (n = 44) and determined the concentrations of persistent OCs such as PCBs, DDT and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB). chlordane compounds (CHLs) and tris-4-chlorophenyl-methane (TCPMe). The contamination pattern of OCs was in the order of DDTs > PCBs > HCHs > CHLsapproximate toHCBapproximate toTCPMe. Compilation of available data indicated that DDT residue levels in human breast milk from Vietnam were among the highest values reported for Asian developing countries as well as developed nations. This result suggests recent usage of DDTs in both north and south Vietnam. Interestingly, in both cities, the p,p'-DDT portion was higher in multiparas than those in primiparas. Considering the fact that the interval between the first and the second child of a mother in Vietnam is usually short, this result probably indicates continuous intake of DDTs in the population. Analysis of infant exposure to DDTs via breast milk suggested that the daily intake rates for number of individuals are close to or above the threshold for adverse effects which may raise concern on children health. (C) 2004 Elsevier Ltd. All rights reserved.
  • Takeuchi, I, S Takahashi, S Tanabe, N Miyazaki
    MARINE ENVIRONMENTAL RESEARCH 57 (5) 397 - 414 0141-1136 2004/06 [Peer-reviewed]
     Scientific journal 
    The concentrations of butyltins along the Japanese coastline were investigated from 1997 to 1999, 7 to 9 years after implemantion of legislation limiting the use of tributyltin (TBT) in Japan. Seawater was sampled at 0.5 m depth, and Caprella spp. were collected from Sargassum spp. and aquaculture facilities from 18 areas within four broad areas along the coastline of Japan, i.e., the Pacific coast of northern Japan, the coast along the Sea of Japan, Tokyo Bay and adjacent areas, and western Japan. Butyltins (MBT, DBT and TBT) were detected in 32 of the 63 seawater samples with average concentrations of 4.6 ng MBT/l, 4.5 ng DBT/l and 6.8 ng TBT/l, respectively. Butyltin concentrations in seawater from western Japan indicate "hot spots" even in unpopulated areas. Butyltins (MBT, DBT and TBT) were detected in all samples of Caprella spp., varying from 2.3 ng BTs/g wet wt in C. penantis R-type from Tobishima Island in the Sea of Japan to 464 ng BTs Ig wet wt in C. decipiens Mayer from Amakusa, western Kyushu. The BT concentrations in Caprella spp. form western Japan were significantly higher than those from other areas, including Tokyo Bay and adjacent areas, where large scale industry and international ports are located. These results indicate that butyltin contamination still remains even in unpopulated areas after the regulation on TBT usage, and that the regulation govering TBT usage since 1990 has not been effective enough to concede recovery of shallow water ecosystems around Japan. (C) 2004 Elsevier LTD. All rights reserved.
  • KS Guruge, S Tanabe
    MARINE POLLUTION BULLETIN 48 (9-10) 1004 - 1008 0025-326X 2004/05 [Peer-reviewed]
     Scientific journal
  • D Ueno, N Kajiwara, H Tanaka, A Subramanian, G Fillmann, PKS Lam, GJ Zheng, M Muchitar, H Razak, M Prudente, KH Chung, S Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 38 (8) 2312 - 2316 0013-936X 2004/04 [Peer-reviewed]
     Scientific journal 
    To elucidate the global distribution of polybrominated diphenyl ethers (PBDEs), these chemicals were determined in the muscle of skipjack tuna (Katsulwonus pelamis) collected from offshore waters of various regions in the world (Japan, Taiwan, Philippines, Indonesia, Seychelles, and Brazil, and the Japan Sea, East China Sea, South China Sea, Indian Ocean, and North Pacific Ocean). PBDEs were detected in almost all the skipjack tuna collected from the locations surveyed (from <0.1 to 53 ng/g of lipid), indicating widespread contamination by these compounds in the marine environment. Residue levels of PBDEs in these samples from the northern hemisphere seem to be higher than those from the southern hemisphere, which is plausibly due to larger usage of these compounds in the northern hemisphere. Higher concentrations of PBDEs were detected in the samples from waters around the East China Sea (up to 53 ng/g of lipid). Developing countries around the East China Sea are supposedly the "hot spots" releasing these chemicals into the marine environment. With regard to the composition of PBDE congeners, the percentage contribution by lower brominated congeners (BDE15, -28, and -47) showed an increasing trend with increasing latitude. On the other hand, higher brominated congeners (BDE153, -154, and -183) showed a reverse trend. These patterns suggest that lower brominated congeners of PBDEs (di-, tri-, and tetra-BDEs) were preferentially transported from pollution sources to northern colder regions through the atmosphere. PBDEs may have a high potency to cause global pollution like PCBs.
  • O Tsydenova, TB Minh, N Kajiwara, Batoev, V, S Tanabe
    MARINE POLLUTION BULLETIN 48 (7-8) 749 - 758 0025-326X 2004/04 [Peer-reviewed]
     Scientific journal 
    Blubber samples of Baikal seals pups (Phoca sibirica) collected in 2001 and 2002 were analyzed for persistent organochlorines (OCs) such as PCBs (polychlorinated biphenyls), DDTs (dichlorodiphenyltrichloroethane and its metabolites), HCHs (hexachlorocyclohexane isomers), CHLs (chlordane related compounds), TCPMe [tris(4-chlorophenyl)methane] and TCPMOH [tris(4-chlorophenyl)methanol]. The distribution pattern of OCs was in the following order: DDTs > PCBs > CHLs > HCHs > TCPMOH > TCPMe. Organochlorine concentrations and composition patterns in eight pup blubber samples (2002) analyzed in the present study were compared with the corresponding levels in juvenile Baikal seals from 1992 survey, and it was found that residue levels of OC compounds have declined during the 10 year period. In particular, concentrations of PCBs, HCHs and CHLs in seals collected in 2002 were approximately two times lower, while DDTs levels were three times lower than the corresponding levels in 1992. Furthermore, higher ratios of beta-HCH/HCHs and p, p'-DDE/DDTs were found in 2002 samples. While comparing the OC levels with those in other seal pups it appeared that all the OC concentrations were lower than the levels in seals from coastal California known as one of the most polluted areas. PCB and DDT concentrations in the present specimens were higher than that in Arctic seal pups. The proportions of tri-, tetra-, penta- and hexachlorobiphenyls in pups captured in 2002 were higher than those in 1992. TEQ concentrations of non- and mono-ortho coplanar PCBs in Baikal seals collected in 2002 were higher than those in seals collected from some locations in the world, where human and industrial activities are extensive, suggesting potential for toxic implications of coplanar PCBs in Baikal seals. (C) 2003 Elsevier Ltd. All rights reserved.
  • T Kunisue, M Someya, Monirith, I, M Watanabe, TS Tana, S Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 46 (3) 405 - 412 0090-4341 2004/04 [Peer-reviewed]
     Scientific journal 
    The present study determined the concentrations of persistent organochlorines (OCs) such as DDT and its metabolites (DDTs), polychlorinated biphenyls (PCBs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), chlordane compounds (CHLs), tris(4-chlorophenyl) methane (TCPMe), and tris(4-chlorophenyl)methanol (TCPMOH) in human breast milk from Cambodia. DDTs, PCBs, HCHs, HCB, CHLs, and TCPMe were detected in almost all the human breast milk samples analyzed, and the concentrations ranged from 310 to 11,000, 6.0 to 87, <0.12 to 21, <0.12 to 8.1, <0.12 to 5.3, and 2.9 to 70 ng/g lipid wt, respectively. TCPMOH was detected in only 10 among 36 samples. Concentrations of DDTs in human breast milk from Cambodia were notably higher than those from developed countries and comparable to those from other developing countries, where usage of DDT for agricultural and public health purposes has been suspected to be continuing still, implying the recent usage of DDT in Cambodia. On the other hand, concentrations of PCBs, HCHs, HCB, and CHLs in human breast milk from Cambodia were 1-2 orders of magnitude less than those from other countries, indicating that Cambodia is one of the less contaminated countries by these OCs. Significant correlation between concentrations of TCPMe and DDTs in human breast milk suggested that exposure to DDT is the source of TCPMe in Cambodian residents. Concentrations of OCs in human breast milk tended to decrease with an increase in the number of children, implying that the first infant would be exposed to higher levels of OCs from breast milk and might be at higher risk by these contaminants, especially DDTs in Cambodia. To our knowledge, this is the first comprehensive study on the residue levels of OCs in human breast milk from Cambodia.
  • JCW Lam, S Tanabe, BSF Wong, PKS Lam
    MARINE POLLUTION BULLETIN 48 (3-4) 390 - 396 0025-326X 2004/02 [Peer-reviewed]
     Scientific journal
  • 平川周作, 岩田久人, 金 恩英, 田辺信介, 宮崎信之, Petrov,E.A
    環境毒性学会誌 7 (2) 55 - 59 2004 [Peer-reviewed]
  • Agusa, T, Kunito, T, Fujihara, J, Kubota, R, Minh, T. B, Trang, P. T. K, Subramanian, An, Iwata, H, Viet, P. H, Tanabe, S
    Biomedical Research on Trace Elements 15 (4) 339 - 341 2004 [Peer-reviewed]
  • JCW Lam, S Tanabe, SKF Chan, EKW Yuen, MHW Lam, PKS Lam
    MARINE POLLUTION BULLETIN 48 (1-2) 174 - 182 0025-326X 2004/01 [Peer-reviewed]
     Scientific journal
  • 國末達也, 染矢雅之, 渡部真文, 豊田卓枝, 黒田優子, 長山淳哉, 田辺信介
    環境科学会誌 17 (1) 37 - 47 2004 [Peer-reviewed]
  • S Tanabe, M Watanabe, TB Minh, T Kunisue, S Nakanishi, H Ono, H Tanaka
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 38 (2) 403 - 413 0013-936X 2004/01 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (coplanar PCBs) were determined in five albatross species collected from the North Pacific and Southern Oceans to assess the north-south differences in residue levels, accumulation patterns, and toxic potential. Black-footed and Laysan albatrosses from the North Pacific Ocean contained higher levels of PCDD/Fs and coplanar PCBs than albatrosses from the Southern Ocean, indicating that emission sources of these contaminants were predominant in the northern hemisphere. Residue levels in albatrosses from the remote North Pacific Ocean far from the point source of pollution were comparable to or higher than those in terrestrial and coastal birds from contaminated areas in developed nations, suggesting the specific exposure and accumulation of PCDD/Fs and coplanar PCBs in albatross. The long life span and ingestion of plastic resin pellets by albatrosses could be the plausible explanations for the elevated accumulation of persistent and lipophilic contaminants including PCDD/Fs and coplanar PCBs in these birds. Relative proportions of PCDFs and coplanar PCBs in albatross were higher than those observed in birds inhabiting terrestrial and coastal areas, suggesting that these toxic chemicals may have higher transportability by air and water than PCDDs. Congener patterns of PCDD/Fs in albatross showed less variability as compared to those in terrestrial species, indicating that contamination patterns of PCDD/Fs were similar within the open ocean environment. Contributions of PCDD/Fs to total TEQs in albatrosses from the open ocean were generally lower than those in terrestrial birds, suggesting different toxic potency of PCDD/Fs and coplanar PCBs on animals inhabiting open ocean and terrestrial environment. Whereas albatrosses from southern oceans retained lower TEQ concentrations, possible adverse effects of PCDD/Fs and coplanar PCBs to black-footed and Laysan albatrosses of the North Pacific Ocean may be suspected from TEQ levels.
  • N Kajiwara, S Matsuoka, H Iwata, S Tanabe, FCW Rosas, G Fillmann, JW Readman
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 46 (1) 124 - 134 0090-4341 2004/01 [Peer-reviewed]
     Scientific journal 
    Wide ranges of organochlorine residues were determined in the blubber of franciscana (Pontoporia blainvillei), estuarine dolphin (Sotalia guianensis), Atlantic spotted dolphin (Stenella frontalis), and long-beaked common dolphin (Delphinus capensis) incidentally caught along Brazilian coastal waters. Concentrations of DDTs and PCBs were the highest, followed by CHLs, TCPMOH, dieldrin, TCPMe, heptachlor epoxide, HCB, and HCHs. Unexpectedly, significant pollution of PCBs, DDTs, TCPMe, and TCPMOH were observed in cetaceans from Brazil, implying the occurrence of local sources in the Southern Hemisphere comparable to those in the Northern Hemisphere, probably by high industrialization in Brazil. On the other hand, CHLs, HCB, HCHs, heptachlor epoxide, and dieldrin residue levels in Brazilian dolphins were much lower than those in other species from the Northern Hemisphere. Significant correlations of TCPMe and TCPMOH were found along with PCBs and DDTs, indicating the highly bioaccumulative nature of all these compounds and/or possible similar pollution sources.
  • CN Fung, JCW Lam, GJ Zheng, DW Connell, Monirith, I, S Tanabe, BJ Richardson, PKS Lam
    ENVIRONMENTAL POLLUTION 127 (2) 203 - 216 0269-7491 2004 [Peer-reviewed]
     Scientific journal 
    Green lipped mussels. Perna viridis, and blue mussels, Mytilus edulis, were collected from seven locations along the east coast of China in September and October 2001. The mussel tissues were analyzed for metals (Ag, As, Cd, Cr, Ni, Pb, Se, Zn, Cu, Fe and Hg), and trace organic contaminants including organochlorine compounds (OCs), polycyclic aromatic hydrocarbons (PAHs; based on 24 individual PAHs). polychlorinated biphenyls (PCBs) and petroleum hydrocarbons (PHCs). Maximum concentrations of Ag, As. Cd, Cr. Ni. Pb, Se, Zn, Cu, Fe and Hg in the mussel tissues were 0.14, 26.76, 5.31, 15.72, 4.78, 2.93, 7.40, 231.0, 54.17, 1002 and 317.3 mug/g dry weight respectively. Levels of DDTs, PAHs, PCBs and PHCs in the mussel samples were 14-640, 456-3495, 1-13 ng/g and 621-2863 mug/g dry weight, respectively. Results of this study indicated that contaminant levels were, in general, higher or at least comparable to those reported in other local or regional studies. Mussel samples collected in Chongming Dao in Shanghai and Jiao Zhou Wan in Qingdao had significantly higher levels of metal and trace organic contaminants among the seven sampling stations. Examination of the contaminant profiles suggests that PHCs originated from petrogenic sources, while both petrogenic and pyrolytic sources were important for PAHs. The generally high levels of metals and organochlorine compounds are probably the result of increasingly intense industrial activities along the east coast of China. An assessment of potential risks to human health due to consumption of the mussels was undertaken for the metals, PCBs, DDTs and chlordanes, and the results indicated that all metals, except Ni, could pose a health risk to heavy seafood consumers, while Hg appears to be of concern even for low level consumers. (C) 2003 Elsevier Ltd. All rights reserved.
  • K Kannan, N Kajiwara, M Watanabe, H Nakata, NJ Thomas, M Stephenson, DA Jessup, S Tanabe
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 23 (1) 49 - 56 0730-7268 2004/01 [Peer-reviewed]
     Scientific journal 
    Concentrations of organochlorine pesticides, polychlorinated biphenyl (PCB) congeners, and butyltins were measured in sea otters and selected prey species (invertebrates) collected from the California (USA) coast. Polychlorinated biphenyls, DDTs (sum of p,p'-dichlorodiphenyldichloroethylene [p,p'-DDE], p,p'-dichlorodiphenyldichloroethane [p,p'-DDD], and p,p'-DDT), and butyltins were the major contaminants found in sea otters and their prey. Lipid-normalized concentrations of PCBs and DDT in sea otter livers were 60- and 240-fold greater than those found in the prey. Great biomagnification of PCBs and DDT in sea otters is suggested to result from their high per-capita intake of diet compared with those of other marine mammals. Profiles of PCB congeners in sea otters and prey species suggest a great capacity of sea otters to biotransform lower-chlorinated congeners. Sea otters seem to possess a greater ability than cetaceans to metabolize PCBs. The 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents of non- and mono-ortho PCBs in sea otters and certain prey species were at or above the theoretical threshold for toxic effects.
  • T Ikemoto, T Kunito, Watanabe, I, G Yasunaga, N Baba, N Miyazaki, EA Petrov, S Tanabe
    ENVIRONMENTAL POLLUTION 127 (1) 83 - 97 0269-7491 2004 [Peer-reviewed]
     Scientific journal 
    Concentrations of IS trace elements (V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Zr, Mo, Ag, Cd, Sb, Cs, Hg, Tl and Pb) were determined in liver. kidney. muscle and hair of Baikal seals, Caspian seals and northern fur seals. All the three species showed the highest concentrations of Hg. V. Mn. Se and Ag in liver, Cd, Co and Tl in kidney, and Cs in muscle among the soft tissues examined. The highest burdens of Zn. Rb and Cs were observed in muscle, Mo and Ag in liver, and Sb and Pb in hair in all the three species. Concentrations of non-essential elements, Rb, Cd, Cs and Hg, showed significant positive correlations among liver, kidney and muscle, whereas correlation coefficients for essential elements, Mn, Co, Cu, Zn and Se, between the three tissues were generally low for all the species. suggesting that homeostasis controls the concentrations of essential elements but not the non-essential elements in the tissues of these animals. Significant age-dependent increase was found in the concentrations of V, Se and Ag in liver and Hg in liver and kidney of all the three species. Hair concentrations showed significant positive correlations with Zn levels in liver and kidney and Hg in muscle for Caspian seals, Hg in liver and kidney for Baikal seals, and Pb in liver for northern fur seals. Furthermore. regression analysis using the data in the present study and in the literature showed significant positive correlations between Hg levels in hair. and liver, kidney and muscle for various species of pinnipeds. These results indicate the possibility of using hair samples for monitoring these trace elements in pinnipeds. (C) 2003 Elsevier Ltd. All rights reserved.
  • D Ueno, S Inoue, S Takahashi, K Ikeda, H Tanaka, AN Subramanian, G Fillmann, PKS Lam, J Zheng, M Muchtar, M Prudente, K Chung, S Tanabe
    ENVIRONMENTAL POLLUTION 127 (1) 1 - 12 0269-7491 2004 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (BTs) including mono- (MBT), di- (DBT), tri-butyltin (TBT) and total tin (SigmaSn), were determined in the liver of skipjack tuna (Katsuwonus pelamis) collected from Asian offshore waters (off-Japan, the Japan Sea, off-Taiwan, the East China Sea. the South China Sea, off-Philippines, off-Indonesia, the Bay of Bengal), off-Seychelles, off-Brazil and open seas (the North Pacific). BTs were detected in all the skipjack tuna collected, suggesting widespread contamination of BTs even in offshore waters and open seas on a global scale. Considering specific accumulation, Sex-, body length- differences and migration of skipjack tuna did not seem to affect BT concentrations, indicating rapid reflection of the pollution levels in seawater where and when they were collected. Skipjack tuna is a suitable bioindicator for monitoring the global distribution of BTs in offshore waters and open seas. High concentrations of BTs were observed in skipjack tuna from offshore waters around Japan, a highly developed and industrialized region (up to 400 ng/g wet weight). Moreover skipjack tuna collected from offshore waters around Asian developing countries also revealed the levels comparable to those in Japan (up to 270 ng/g wet weight) which may be due to the recent improvement in economic status in Asian developing countries. High percentages (almost 90%) of BTs in total tin (SigmaSn: sum of inorganic tin+ organic tin) were found in the liver of skipjack tuna from offshore waters around Asian developing countries. This finding suggests that the anthropogenic BTs represent the major source of Sri accumulation in skipjack tuna from these regions. (C) 2003 Elsevier Ltd. All rights reserved.
  • J Fujihara, T Kunito, R Kubota, S Tanabe
    COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY 136 (4) 287 - 296 1532-0456 2003/12 [Peer-reviewed]
     Scientific journal 
    Concentrations of total arsenic and individual arsenic compounds were determined in liver samples of pinnipeds (northern fur seal Callorhinus ursinus and ringed seal Pusa hispida), seabirds (black-footed albatross Diomedea nigripes and black-tailed gull Larus crassirostris) and sea turtles (hawksbill turtle Eretmochelys imbricata and green turtle Chelonia mydas). Among these species, the black-footed albatross contained the highest hepatic arsenic concentration (5.8+/-3.7 mug/g wet mass). Arsenobetaine was the major arsenic species found in the liver of all these higher tropic marine animals. To investigate the cause of high accumulation of arsenobetaine, subcellular distribution of arsenic and relationship between arsenobetaine and glycine betaine concentrations were examined in the livers of these animals. There was no relationship between total arsenic concentration and its subcellular distribution in liver tissues. However, a significant negative correlation was found between arsenobetaine and glycine betaine concentrations in the liver of six species examined. This result may indicate that arsenobetaine is accumulated in these marine animals as an osmolyte along with glycine betaine, which is a predominant osmolyte in marine animals because the chemical structure and properties of arsenobetaine are similar to those of glycine betaine. (C) 2003 Elsevier Inc. All rights reserved.
  • K Ebisuda, T Kunito, J Fujihara, R Kubota, Y Shibata, S Tanabe
    TALANTA 61 (6) 779 - 787 0039-9140 2003/12 [Peer-reviewed]
     Scientific journal 
    High concentrations of arsenic were observed in the blubber of ringed seals (Pusa hispida) in our previous study. To better understand the arsenic accumulation in blubber of marine mammals, arsenicals in the blubber of ringed seal were characterized using high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS). The most predominant water-soluble arsenical in the blubber was dimethylarsinic acid (DMA), in spite of the predominance of arsenobetaine in other tissues. Lipid-soluble fraction was hydrolyzed under mild (tetraethylammonium hydroxide (TEAH) hydrolysis) and strong (NaOH hydrolysis) conditions, and then an aliquot of hydrolysate was injected onto HPLC-ICPMS. Both TEAH-labile and TEAH-stable/NaOH-labile lipid-soluble fractions contained precursors of DMA. These results suggest that the blubber might be the pool of DMA and DMA-containing precursors in ringed seals. (C) 2003 Elsevier B.V. All rights reserved.
  • T Kunisue, M Watanabe, A Subramanian, AM Titenko, S Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 45 (4) 547 - 561 0090-4341 2003/11 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated biphenyls (PCBs), including non-, mono-, and di-ortho congeners, were determined in migratory and resident birds collected from India and Lake Baikal in Russia. In the 11 different species examined, total PCBs concentrations were in the range of 11-4500 ng/g (wet wt). IUPAC 105, 118, 138, 153, and 180 were the predominant congeners in almost all the birds. White-cheeked tern collected from India and common tern collected from Lake Baikal showed high PCBs concentrations of 4400 ng/g (wet wt) and 4500 ng/g (wet wt), respectively, and accumulated relatively high ratios of penta-CBs (IUPAC 118, 105, 99). Toxic equivalents (TEQs) of non- and mono-ortho PCB congeners in birds collected from India and Lake Baikal were in the range of 1.5-56 and 2.8-370 pg/g wet wt, respectively. Toxic assessment results led by calculated TEQs of the transfer to eggs from female birds revealed that TEQs in most of migratory and resident birds were comparable to the lowest observable effect level (LOAEL) of chicken which is a highly sensitive species against dioxin-like compounds. Calculated transfer TEQs to eggs of common tern collected from Lake Baikal in autumn, however, exceeded the LOAEL of CYP1A induction in bald eagle embryos and ED50 of that in pheasant embryos, suggesting that embryo toxicity by coplanar PCBs in some avian species breeding in Lake Baikal is possible.
  • Monirith, I, T Kunisue, H Iwata, S Tanabe, TS Tana
    MARINE POLLUTION BULLETIN 46 (10) 1341 - 1348 0025-326X 2003/10 [Peer-reviewed]
     Scientific journal
  • R Yoshitome, T Kunito, T Ikemoto, S Tanabe, H Zenke, M Yamauchi, N Miyazaki
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 37 (20) 4597 - 4602 0013-936X 2003/10 [Peer-reviewed]
     Scientific journal 
    Concentrations of anthropogenic radionuclides were measured in the muscle of marine mammals collected from various locations all over the world, and the global distribution of Cs-137 in marine mammals was investigated. K-40 was detected in all the specimens of marine mammals with no apparent difference between regions. An anthropogenic radionuclide, Cs-137, was detected in most of the species of marine mammals. With regard to the worldwide distribution of Cs-137, the highest concentration was noticed in the U.K. coast, followed by Lake Baikal, and decreases toward the southern sampling points. A strong positive correlation was observed between Cs-137 levels in the muscle of marine mammals and the ambient seawater. Marine mammals feeding on fishes showed a higher concentration factor (CF) for Cs-137 than those feeding on cephalopods. To our knowledge, this is the first report on the global distribution of Cs-137 and the effect of feeding habits on the CF values of Cs-137 in marine mammals.
  • D Ueno, S Takahashi, H Tanaka, AN Subramanian, G Fillmann, H Nakata, PKS Lam, J Zheng, M Muchtar, M Prudente, KH Chung, S Tanabe
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 45 (3) 378 - 389 0090-4341 2003/10 [Peer-reviewed]
     Scientific journal 
    Concentrations of organochlorines (OCs) representing persistent organic pollutants (POPS), such as polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), chlordane compounds (CHLs), hexachlorocyclohexane isomers (HCHs), and hexachlorobenzene (HCB), were determined in the liver of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters of various regions in the world (offshore waters around Japan, Taiwan, Philippines, Indonesia, Seychelles, and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Bay of Bengal, and the North Pacific Ocean). OCs were detected in livers of all of the skipjack tuna collected from the locations surveyed, supporting the thesis that there is widespread contamination of persistent OCs in the marine environment. Within a location, no significant relationship between growth-stage (body length and weight) and OC concentrations (lipid weight basis) was observed, and the OC residue levels were rather uniform among the individuals. Interestingly, the distribution of OC concentrations in skipjack tuna was similar to those in surface seawaters from which they were taken. These results suggest that OC concentrations in skipjack tuna could reflect the pollution levels in seawater from which they are collected and that this species is a suitable bioindicator for monitoring the global distribution of OCs in offshore waters and the open ocean. Concentrations of PCBs and CHLs in skipjack tuna were higher in offshore waters around Japan (up to 1100 and 250 ng/g lipid wt, respectively), suggesting the presence of sources of PCBs and CHLs in Japan. High concentrations of DDTs and HCHs were observed in samples from the Japan Sea, the East China Sea, the South China Sea, and the Bay of Bengal (up to 1300 and 22 ng/g lipid wt, respectively). This result suggests recent use of technical DDT and HCH for agricultural and/or public health purposes in Russia, China, India, and some other developing Asian countries. Relatively high concentrations of PCBs, CHLs, HCHs, and HCB were also observed in samples collected from some locations in the middle of the Pacific Ocean, indicating the expansion of OC contamination on a global scale. Considering these facts, continuous studies monitoring these compounds in offshore waters and the open seas, using skipjack tuna as a bioindicator, are needed to further understand the future trend of contamination.
  • N Kajiwara, D Ueno, Monirith, I, S Tanabe, M Pourkazemi, DG Aubrey
    MARINE POLLUTION BULLETIN 46 (6) 741 - 747 0025-326X 2003/06 [Peer-reviewed]
     Scientific journal 
    Organochlorine compounds (OCs) were determined in the five species of sturgeons collected from coastal waters of Caspian Sea in Kazakhstan, Azerbaijan, Turkmenistan and Iran during 2001 and 2002 to understand their status of contamination and accumulation features. Among OCs examined, concentrations of DDTs (DDT and its metabolites) were predominant in all the sturgeon samples with concentrations ranging from 73 to 3 1,000 ng/g on lipid weight basis, followed by PCBs, CHLs, HCHs, HCB, dieldrin, TCPMOH, and heptachlor epoxide in order. The concentrations of OCs in beluga (Huso huso) were the highest among all the five species. When comparing residue levels among same species, OC residues were highest in sturgeons from Azerbaijan and Kazakhstan and lowest in Turkmenistan. However, the concentrations of HCHs, dieldrin, and heptachlor epoxide in sturgeons showed less geographical variability. (C) 2003 Elsevier Science Ltd. All rights reserved.
  • R Kubota, T Kunito, S Tanabe
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 22 (6) 1200 - 1207 0730-7268 2003/06 [Peer-reviewed]
     Scientific journal 
    Concentrations of total arsenic and individual arsenic compounds were determined in livers of birds, cetaceans, pinnipeds, and sea turtles by using hydride generation-atomic absorption spectrometry and high-performance liquid chromatography/inductively coupled plasma-mass spectrometry. Hepatic arsenic concentrations in loggerhead turtles (11.2 +/- 3.0 wg/g dry wt) and black-footed albatrosses (12.2 +/- 10.8 mug/g dry wt) were extremely high among the species examined, and the values were comparable with those of lower trophic marine animals such as fishes, cephalopods, crustaceans, and shellfishes. In all the species, arsenobetaine was the predominant arsenic compound in the livers. Especially, for black-footed albatrosses and black-tailed gull, the mean percentage of arsenobetaine was as high as 97.1 and 87.5, respectively, of extractable arsenic. The present study is among the first on arsenic speciation in avian species. Total arsenic concentration was strongly correlated with the concentration of arsenobetaine, while no significant relationship was observed between total arsenic concentration and other arsenic compounds in these animals. Because arsenobetaine is known to be rapidly excreted into the urine in humans and experimental animals, the observed results suggest that higher trophic marine animals might have a unique metabolism of arsenobetaine and that arsenobetaine plays an important role in the accumulation of arsenic in these animals.
  • S Tanabe, S Niimi, TB Minh, N Miyazaki, EA Petrov
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 44 (4) 533 - 545 0090-4341 2003/05 [Peer-reviewed]
     Scientific journal 
    To examine temporal trends of organochlorine (OC) contamination in Lake Baikal and the Caspian Sea, concentrations of persistent OCs, such as DDT and its metabolites (DDTs), polychlorinated biphenyls (PCBs), hexachlorocyclohexane (HCHs), chlordane compounds (CHLs), tris(4-chlorophenyl)methane (TCPMe), and tris(4-chlorophenyl)methanol (TCPMOH), in the blubber of female seals were determined. Collections were made in 1992, 1993, 1995 and 1998. DDT concentrations in Baikal and Caspian seals showed a rapid decline during 1992 to 1998, while the concentrations of PCBs declined slowly. Elevated concentrations of HCHs were found in Caspian seals and there was no decline in their concentrations during 1993 to 1998, which could be due to extensive usage of HCHs around Caspian Sea in recent years. Trends of TCPMe and TCPMOH residues in Caspian seals were similar to that of DDTs. The pattern of PCB isomers in both Baikal seals and Caspian seals exhibited little temporal variations. Concentrations of non-ortho coplanar PCBs have declined at a faster rate than those of mono-ortho congeners. Compilation of available data on OC contamination in the North Pacific, Antarctic, Caspian Sea, Lake Baikal, and India suggested that the time trend of residues of contaminants during the 1990s were different among these regions. Residue levels of OC insecticides have declined slowly while PCBs remained at a steady state in the open oceans and the Antarctic. The magnitude of temporal variation in Lake Baikal seemed to be higher than that in the Caspian Sea. Residue concentrations of OCs have increased in Ganges River dolphins from 1989-92 to 1994-96, suggesting that tropical, developing countries are potential emission source of OCs.
  • NH Minh, TB Minh, M Watanabe, T Kunisue, Monirith, I, S Tanabe, S Sakai, A Subramanian, K Sasikumar, PH Viet, BC Tuyen, TS Tana, MS Prudente
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 37 (8) 1493 - 1502 0013-936X 2003/04 [Peer-reviewed]
     Scientific journal 
    Open landfill dumping areas for municipal wastes in Asian developing countries have recently received particular attention with regard to environmental pollution problems. Because of the uncontrolled burning of solid wastes, elevated contamination by various toxic chemicals including dioxins and related compounds in these dumping sites has been anticipated. In this study, concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (PCBs) were determined in soils from dumping sites in the Philippines, Cambodia, India, and Vietnam. Residue concentrations of PCDD/Fs and coplanar PCBs in dumping site soils were apparently greater than those in soils collected in agricultural or urban areas far from dumping sites, suggesting that dumping sites are potential sources of PCDD/Fs and related compounds. Observed PCDD/F concentrations in soils from dumping sites in the Philippines and Cambodia were comparable or higher than those reported for dioxin-contaminated locations in the world (e.g., near the municipal waste incinerators and open landfill dumping sites). Homologue profiles of PCDD/Fs in dumping site soils from the Philippines and, to a lesser extent, from Cambodia and India reflected patterns of samples representing typical emissions, while profiles of agricultural or urban soils were similar to those of typical environmental sinks. This result suggests recent formation of PCDD/Fs in dumping site areas and that open dumping sites are a potential source of dioxins in Asian developing countries. Uncontrolled combustions of solid wastes by waste pickers, generation of methane gas, and low-temperature burning can be major factors for the formation of dioxins in dumping sites. Elevated fluxes of PCDD/Fs to soils in dumping sites were encountered in the Philippines, Cambodia, India, and Vietnam-Hanoi, and these levels were higher than those reported for other countries. Considerable loading rates of PCDD/Fs in the dumping sites of these countries were observed, ranging from 20 to 3900 mg/yr (0.12-35 mg TEQ/yr). PCDD/F concentrations in some soil samples from the Philippines, Cambodia, India, and Vietnam-Hanoi exceeded environmental guideline values, suggesting potential health effects on humans and wildlife living near these dumping sites. The estimated intakes of dioxins via soil ingestion and dermal exposure for children were higher than those for adults, suggesting greater risk of dioxin exposure for children in dumping sites. To our knowledge, this is the first comprehensive study on PCDD/Fs contamination in open dumping sites of Asian developing countries. On the basis of the result of this study, we have addressed a new environmental issue that open dumping sites are potential sources of PCDD/Fs and related compounds, and dioxin contamination in dumping sites may become a key environmental problem in developing countries.
  • Monirith, I, D Ueno, S Takahashi, H Nakata, A Sudaryanto, A Subramanian, S Karuppiah, A Ismail, M Muchtar, JS Zheng, BJ Richardson, M Prudente, ND Hue, TS Tana, AV Tkalin, S Tanabe
    MARINE POLLUTION BULLETIN 46 (3) 281 - 300 0025-326X 2003/03 [Peer-reviewed]
     
    Contamination of persistent organochlorines (OCs) such as PCBs (polychlorinated biphenyls), DDT and its metabolites (DDTs), HCH (hexachlorocyclohexane) isomers (HCHs), chlordane compounds (CHLs), and HCB (hexachlorobenzene) were examined in mussels collected from coastal waters of Asian countries such as Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Far East Russia, Singapore, and Vietnam in 1994, 1997, 1998, 1999, and 2001 to elucidate the contamination status, distribution and possible pollution sources and to assess the risks on aquatic organisms and human. OCs were detected in all mussels collected from all the sampling sites investigated. Considerable residue levels of p,p'-DDT and alpha-HCH were found in mussels and the concentrations of DDTs and HCHs found in mussels from Asian developing countries were higher than those in developed nations suggesting present usage of DDTs and HCHs along the coastal waters of Asian developing countries. On the other hand, lower concentrations of PCBs detected in mussels from Asian developing countries than those in developed countries indicate that PCBs contamination in mussels is strongly related to industrial and activities. To our knowledge, this is a first comprehensive report on monitoring OCs pollution in the Asia-Pacific region. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • 越智久尚, 藤田慎二郎, 山内正信, 國頭 恭, 田辺信介
    環境化学 13 (3) 753 - 764 2003 [Peer-reviewed]
  • 宝来佐知子, 渡邉 泉, 久野勝治, 田辺信介, 岩水良和, 本村 健, 平岡 考
    環境化学 13 (3) 719 - 732 2003 [Peer-reviewed]
  • 越智久尚, 藤田慎二郎, 山内正信, 國頭 恭, 田辺信介
    環境化学 13 (3) 643 - 651 2003 [Peer-reviewed]
  • Hoshino, H, Fujita, S, Goto, Y, Isono, T, Ishinazaka, T, Sakurai, Y, Iwata, H, Kazusaka, A, Ishizuka, M, Tanabe, S
    Japanese Journal of Environmental Toxicology 6 (1) 1 - 10 2003 [Peer-reviewed]
  • 渡邉 泉, 寶来佐和子, 荒井雄介, 久野勝治, 林 光武, 谷地森秀二, 國頭 恭, 田辺信介
    環境科学会誌 16 (4) 317 - 328 2003 [Peer-reviewed]
  • DW Connell, CN Fung, TB Minh, S Tanabe, PKS Lam, BSF Wong, MHW Lam, LC Wong, RSS Wu, B Richardson
    WATER RESEARCH 37 (2) 459 - 467 0043-1354 2003/01 [Peer-reviewed]
     Scientific journal 
    Eggs of two Ardeid species, the Little Egret (Egretta garzetta) and the Black-crowned Night Heron (Nycticorax nycticorax), were collected from two egretries located in the New Territories of Hong Kong with one located near the internationally acclaimed wetland reserve, the Mai Po Marshes, and the other in a remote site (A Chau). The eggs were analysed for organochlorine (OC) compounds including the DDTs, PCBs, hexachlorocyclohexanes (HCHs) and the chlordanes (CHLs). All of the OCs under investigation were detected in the eggs of both species with significantly higher levels in the Little Egret (DDTs, 560-2200: PCBs, 270-1700; CHLs, 81-470ng g(-1) wet weight) than the Night Heron (DDTs, 210-1200; PCBs, 85-600; CHLs 59-75ng g(-1) wet weight). The DDTs consisted mainly of DDE with levels ranging from 85% to 95% of the total. The HCHs were at about the same levels in both species (8.4-30ng g(-1) wet weight). All of the OCs had linear concentration probability distributions on a log-normal basis which were used to evaluate exposure associated with these compounds as part of a probabilistic risk analysis. A linear dose/response relationship for the percentage reduction in the survival of young associated with DDE in eggs was developed. This probabilistic relationship was used to establish the threshold level (1000ng g(-1) wet weight) at which there was a significant level of reduction in the survival of young above zero and the variability in DDE concentrations at this effect level. Using a threshold level of 1000ng g(-1) the calculated Risk Quotient (RQ) had a 12.4% probability of RQ exceeding unity with the Night Heron, and 40.9% with the Little Egret. These results indicate that the DDTs in eggs would be expected to be associated with adverse effects on the survival of young of both species, particularly the Little Egret. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • D Ueno, S Inoue, K Ikeda, H Tanaka, H Yamada, S Tanabe
    ENVIRONMENTAL POLLUTION 125 (2) 227 - 235 0269-7491 2003 [Peer-reviewed]
     Scientific journal 
    Organochlorines (OCs) representing Persistent Organic Pollutants (POPs) such as PCBs (polychlorinated biphenyls), DDTs (DDT and its metabolites), CHLs (chlordane compounds), HCHs (hexachlorocyclohexane isomers) and HCB (hexachlorobenzene) were determined in the liver of Japanese common squid (Todarodes pacficus) collected from the waters around Japan (Japan Sea and western North Pacific Ocean). Among OCs concentrations, PCBs (upto 5600 ng/g lipid wt.) were the highest, and those of other OCs were in the order of DDT > CHLs > HCHs > HCB. Studies on growth trend and seasonal variation of OCs in this species suggest a rapid reflection of the pollution levels in seawater where and when they were collected, regardless of body-length and time of collection. These results indicate that Japanese common squid is a suitable bioindicator for monitoring OCs pollution in waters around Japan. With regard to the geographical distribution of OCs in this species collected from waters around Japan, OCs concentrations in specimens from Japan Sea were higher than those from the Pacific Ocean. This result might reflect some existing of local pollution sources of OCs around Japan Sea, and slower water exchange between Japan Sea and open ocean. (C) 2003 Elsevier Science Ltd. All rights reserved.
  • T Kunisue, M Watanabe, A Subramanian, A Sethuraman, AM Titenko, Qui, V, M Prudente, S Tanabe
    ENVIRONMENTAL POLLUTION 125 (2) 157 - 172 0269-7491 2003 [Peer-reviewed]
     Scientific journal 
    Concentrations of organochlorine contaminants including polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlo to benzene (HCB) were determined in the resident and migratory birds, which were collected from India, Japan, Philippines, Russia (Lake Baikal) and Vietnam. Accumulation patterns of organochlorine concentrations in resident birds suggested that the predominant contaminants of each country were as follows: Japan-PCBs Philippines-PCBs and CHLs, India-HCHs and DDTs, Vietnam-DDTs, and Lake Baikal-PCBs and DDTs. The migratory birds from Philippines and Vietnam retained mostly the highest concentrations of DDTs among the organochlorines analyzed, indicating the presence of stopover and breeding grounds of those birds in China and Russia. On the other hand, migratory birds from India and Lake Baikal showed different patterns of organochlorine residues, reflecting that each species has inherent migratory routes and thus has exposure to different contaminants. Species which have breeding grounds around the Red Sea and Persian Gulf showed high levels of PCBs, indicating the presence of areas heavily polluted by PCBs in the Middle East. (C) 2003 Elsevier Science Ltd. All rights reserved.
  • 越智久尚, 藤田慎二郎, 山内正信, 國頭 恭, 田辺信介
    環境化学 13 (1) 41 - 49 2003 [Peer-reviewed]
  • 渡邉 泉, 田辺信介
    環境化学 13 (1) 31 - 40 2003 [Peer-reviewed]
  • H Sakai, R Kasai, S Takahashi, S Tanabe
    NIPPON SUISAN GAKKAISHI 69 (1) 10 - 22 0021-5392 2003/01 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (MBT, DBT, TBT) were determined in surface sediments, sediment cores, cultured fishes and pearl oysters collected from Uwa Sea, Japan. TBT concentrations in surface sediments ranged from 2.8 to 930 ng/g dry wt, which were comparable to those in urban regions such as Tokyo Bay, Osaka Bay and Dokai Bay. SigmaBTs (MBT + DBT + TBT) concentrations in surface sediments from fish culture areas were significantly higher than those from pearl oyster areas. In case of sediment cores, BTs concentration was the highest in the surface layer and decreased with core depth. SigmaBTs concentrations in pearl oysters were lower than those in other species of bivalves from various coastal waters around the world, whereas SigmaBTs concentrations in cultured fish from Uwa Sea were comparable to those reported in Osaka Bay. Higher proportions of TBT in SigmaBTs residues were found in fish and pearl oysters than in sediments. Although TBT concentrations found in cultured fishes were less than the tolerable level estimated from ADI suggested by the Ministry of Health and Welfare, efforts to reduce the residue levels are needed for the conservation of ecosystems.
  • N Kajiwara, M Watanabe, S Tanabe, K Nakamatsu, M Amano, N Miyazaki
    MARINE POLLUTION BULLETIN 44 (10) 1089 - 1099 0025-326X 2002/10 [Peer-reviewed]
     Scientific journal 
    Organochlorine compounds (OCs) such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlordane related compounds, hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), tris(4-chloro-phenyl) methane (TCPMe) and tris(4-chlorophenyl) methanol were determined in the blubber of Dall's porpoises (Phocoenoides dalli) collected from Japanese coastal waters in 1998/1999. Among OCs analyzed, PCBs were the predominant contaminants with concentrations ranging from 1.5 to 39 mug/g on a wet weight basis. OCs concentrations were relatively low and less variable in mature females possibly due to the lactational excretion from their bodies, while in males the concentrations were increased with body length. Concentrations and compositions of DDTs and HCHs showed significant differences between the truei-type population off the Pacific coast of northern Japan and dalli-type from the Sea of Japan/Okhotsk. suggesting its usefulness to discriminate different populations. OCs levels detected in truei-type porpoises collected in 1998/1999 were lower than those collected in 1984, except TCPMe. On the other hand, except DDTs, the residue levels of other organochlorines in dalli-type porpoises showed no significant decrease since 1984. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • A Sudaryanto, S Takahashi, Monirith, I, A Ismail, M Muchtar, J Zheng, BJ Richardson, A Subramanian, M Prudente, ND Hue, S Tanabe
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 21 (10) 2119 - 2130 0730-7268 2002/10 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (BTs) including mono-, di-, and tributyltin and total tin (SigmaSn), were determined in green mussels (Perna viridis) from various Asian developing countries, such as Cambodia, China (Hong Kong and southern China), Malaysia, India, Indonesia, the Philippines, and Vietnam. to elucidate the contamination status, distribution, and possible sources and to assess the risks on aquatic organisms and humans. Butyltin compounds were detected in green mussels collected from all the sampling location investigated, suggesting widespread contamination of BTs along the coastal waters of Asian developing countries. Among butyltin derivatives, tributyltin (TBT) was the predominant compound, indicating its ongoing usage and recent exposures in Asian coastal waters. Higher concentrations of BTs were found in mussels collected at locations with intensive maritime activities, implying that the usage of TBT as a biocide in antifouling paints was a major source of BTs. In addition, relatively high concentrations of BTs were observed in mussels from aquaculture areas in Hong Kong and Malaysia, as it has been reported in Thailand. With the recent improvement in economic status in Asia, it is probable that an increase in TBT usage will occur in aquaculture, Although contamination levels were generally low in mussel samples from most of the Asian developing countries, some of those from polluted areas in Hong Kong, India. Malaysia, the Philippines, and Thailand revealed levels, comparable to those in developed nations. Furthermore, the concentrations of TBT in some mussels from polluted areas exceeded the threshold for toxic effects on organisms and estimated tolerable average residue levels as seafoods for human consumption, A significant correlation was observed between the concentrations of SigmaBTs and SigmaSn in mussels, and SigmaBTs were made up mostly 100% of SigmaSn in mussels taken from locations having intensive maritime/human activities. This suggests that anthropogenic BTs represent the major source of tin accumulation in mussels. To our knowledge, this is a first comprehensive report on butyltin pollution monitoring in developing countries in the Asia-Pacific region.
  • TB Minh, T Kunisue, NTH Yen, M Watanabe, S Tanabe, ND Hue, Qui, V
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 21 (10) 2108 - 2118 0730-7268 2002/10 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorines (OCs), such as polychlorinated biphenyls (PCBs). 1,1,1 trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), and chlordane compounds (CHLs), were determined in whole-body homogenates of resident and migratory birds collected from the Red River estuary, North Vietnam, during March and October 1997. Contamination pattern was in the order of DDTs > PCBs > HCHs > CHLs > HCB in both resident and migratory birds. Residue concentrations, according to the feeding habit, showed little variability, which may reflect relatively similar trophic levels of the bird species analyzed. Resident birds accumulated greater concentrations of DDTs as compared to migrants. In contrast, HCH residues were greater in migratory species. Higher proportion, of p,p'-DDT to total DDT concentrations were found in many species of residents and migrants, indicating recent exposure to technical DDT in northern Vietnam. Congener-specific PCB analysis showed the predominance of penta- and hevachlorobiphenyls in all the species analyzed. Estimation of hepatic microsomal enzyme activities suggested higher metabolic capacity for PCB congeners in shore birds from Vietnam as compared to higher-trophic predator birds and marine mammals. Comparison of OC residues in avian species in Asia-Pacific revealed that DDT residues in resident birds in North Vietnam are among the highest values reported for the countries surveyed, suggesting recent usage of DDT in Vietnam. Available data for birds, fish, and bivalves from the recent Asia-Pacific Mussel Watch Program suggested that Vietnam might be a potential source of DDT contamination in Asian developing countries. To our knowledge, this is the first study of the OC accumulation in avian species from Vietnam.
  • A Kubota, M Someya, M Watanabe, S Tanabe
    NIPPON SUISAN GAKKAISHI 68 (5) 695 - 700 0021-5392 2002/09 [Peer-reviewed]
     Scientific journal 
    The present study determined concentrations of polychlorinated biphenyls (PCBs) including coplanar congeners, polychlorinated dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs) in coastal sediments from Uwa Sea, western coast of Shikoku, Japan, in order to clarify the contamination status and historical trend of these chemicals. Concentrations of PCBs and PCDDs/DFs in surface sediments of Uwa Sea were cleary lower than those in other coastal areas of Japan. PCB concentrations in sediment cores showed a decreasing trend toward the upper layers. Concentrations of PCDDs/DFs in surface sediments in this study were lower than those in 1968. These results suggest that Uwa Sea is a suitable area for fish aquaculture.
  • EY Kim, ME Hahn, H Iwata, S Tanabe, N Miyazaki
    MARINE ENVIRONMENTAL RESEARCH 54 (3-5) 285 - 289 0141-1136 2002/09 [Peer-reviewed]
     Scientific journal 
    Species differences in sensitivity to related planar halogenated aromatic hydrocarbons (PHAH) add significant uncertainty in assessing the ecological risk to aquatic mammals. To investigate mechanisms of PHAH sensitivity in aquatic mammals, we cloned and sequenced the cDNA of Baikal seal aryl hydrocarbon receptor (AHR), an intracellular protein that initiates PHAH-mediated effects. The Baikal seal AHR cDNA has an open reading frame of 843 amino acid residues with a predicted molecular mass of 94.6 kDa. Comparison of AHR amino acid sequences indicated a high degree of sequence conservation (98%) between Baikal and harbor seals. The high conservation of AHRs between Baikal and harbor seals indicates that these seals express AHR proteins closely related structurally. In our previous report (Kim & Hahn, 2002), the dioxin-binding affinity of the harbor seal AHR was at least as high as that of the AHR from a dioxin-sensitive strain of mice, suggesting that this seal species may be sensitive to PHAH effects. This implies that Baikal seal may also be sensitive to dioxin effects. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • R Kubota, T Kunito, S Tanabe, H Ogi, Y Shibata
    APPLIED ORGANOMETALLIC CHEMISTRY 16 (8) 463 - 468 0268-2605 2002/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of total arsenic and individual arsenic compounds were determined in several tissues and eggs of the black-tailed gull (Larus crassirostris) to characterize accumulation and maternal transfer to eggs. A relatively high concentration of arsenic was observed in the liver, kidney, pancreas, muscle and gonad. The transfer rate of arsenic to eggs of the black-tailed gull was about 10%. Chemical speciation analysis revealed that arsenobetaine was the major arsenic compound in all the tissues. Dimethylarsinic acid, methylarsonic acid, arsenocholine, and an unidentified arsenic compound were also detected as minor constituents. Like maternal tissues, egg also contained arsenobetaine as the major arsenic compound and dimethylarsinic acid as a minor compound. These results suggest that arsenobetaine and dimethylarsinic acid can transfer from the mother bird to the eggs. To our knowledge, this is the first report on the maternal transfer of arsenic species to eggs of seabirds. Copyright (C) 2002 John Wiley Sons, Ltd.
  • K Ebisuda, T Kunito, R Kubota, S Tanabe
    APPLIED ORGANOMETALLIC CHEMISTRY 16 (8) 451 - 457 0268-2605 2002/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of total arsenic and arsenic compounds were determined in tissues of ringed seals (Phoca hispida) using hydride generation-atomic absorption spectrometry and high-performance liquid chromatography-inductively coupled plasma mass spectrometry. Arsenic was accumulated at high concentrations in the blubber as lipid-soluble arsenic compounds (arsenolipids). Arsenobetaine (AB) was the most predominant arsenical in the liver, kidney, muscle and gonad, accounting for about 70% of total arsenic in these tissues. Significant positive correlations were observed for AB concentrations among liver, kidney, muscle and gonad, suggesting that the distribution of AB among these tissues was at equilibrium. Concentrations of AB in the tissues were elevated up to 1-3 years of age, and then fell to a lower level. In contrast, dimethylarsinic acid concentration was significantly increased with age in the liver and kidney. Arsenocholine was also detected in the liver, kidney and gonad, but was not detected in the muscle. Among the arsenic compounds, only AB showed a considerable decrease of the concentration in the gastrointestinal contents with their passing through the gastrointestinal tract, which might indicate that the absorption rate of AB was higher than the absorption rates of other arsenic compounds in ringed seals. To our knowledge, this is the first report of arsenic speciation in several tissues and gastrointestinal contents in marine mammals. Copyright (C) 2002 John Wiley Sons, Ltd.
  • Watanabe, I, T Kunito, S Tanabe, M Amano, Y Koyama, N Miyazaki, EA Petrov, R Tatsukawa
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 43 (1) 109 - 120 0090-4341 2002/07 [Peer-reviewed]
     Scientific journal 
    Concentrations of heavy metals (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Co, and Hg) were determined in the muscle, liver, and kidney of 42 Caspian seals and fishes collected from the Caspian Sea in 1993. Higher Mn and lower Fe and Cu concentrations were found in the liver in comparison with other marine pinnipeds. Lower Cu concentrations in the Ever appear to be a common feature in small seals belonging to subgenus Pusa, which include ringed, Baikal, and Caspian seals. However, low Fe and high Mn in livers were specific to Caspian seal. Concentrations of toxic metals such as Hg and Cd were relatively low. Pinniped species can be divided into two groups, based on accumulations of Cd or Hg in the liver, Interestingly, it was found that Cd-accumulating groups feed on invertebrates, whereas the preferred diet of Hg accumulators is fish. Caspian seals seemed to belong to the Hg-accumulating group. Cd and Hg concentrations in the liver and kidney of young animals increased with age. Mercury concentrations in adult animals increased with age continuously, whereas Cd concentrations in adult animals decreased. This trend might be due to preferential feeding habits and shift in ratio of Hg and Cd in the diet (i.e., invertebrates to fish).
  • T Arai, T Ikemoto, T Kunito, S Tanabe, N Miyazaki
    JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM 82 (2) 303 - 305 0025-3154 2002/04 [Peer-reviewed]
     Scientific journal 
    dElemental composition and ontogenic change patterns of Sr and Ca were examined in conger eel, Conger myriaster, otoliths. Accumulations of the major elements of seawater, K, Mg, and Na, into otoliths were smaller than the accumulations of 19 other minor elements whose concentration, were determined. Strontium content and Sr:Ca ratios in the otolith fluctuated during the life history transect at 100 to 200 mum from the core of the otolith, indicating a period of metamorphosis. Changes in Sr content and Sr:Ca ratios may be associated with internal physiological factor such as metamorphosis in the early developmental stage in the conger eel.
  • Y Anan, T Kunito, T Ikemoto, R Kubota, Watanabe, I, S Tanabe, N Miyazaki, EA Petrov
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 42 (3) 354 - 362 0090-4341 2002/04 [Peer-reviewed]
     Scientific journal 
    Concentrations of V. MD, Fe. Cr. Co, Cu, Zn, As, Se, Mo, Ag, Cd, Tl, Hg, Pb, and organic mercury (Org-Hg) were determined in liver. kidney. and muscle of healthy Caspian seals (Phoca caspica) collected in 1998. These concentrations were compared with those of seals infected with canine distemper virus (CDV) found stranded along the coastal areas in 2000. Concentrations of toxic elements (As, Ag, Cd, Tl, Hg, Pb. and Org-Hg) in Caspian seals stranded in 2000 were comparable or lower than those of samples collected in 1998 and in other pinnipeds, Thus it may be inferred that these elements were not the causative agents in the deaths of the seals. In contrast. concentrations of Zn and Fe were much higher in diseased Caspian seals than those in other pinnipeds. Zinc concentrations in all tissues of Caspian seals also increased during 1993-2000. Furthermore, negative correlations were found between blubber thickness and hepatic and renal Zn concentrations. These results imply the disturbance in homeostatic control and nutritional status of essential elements in Caspian seals stranded in 2000.
  • T Kunisue, TB Minh, K Fukuda, M Watanabe, S Tanabe, AM Titenko
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 36 (7) 1396 - 1404 0013-936X 2002/04 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorines (OCs) such as polychlorinated biphenyls (PCBs), DDT and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), and chlordane compounds (CHLs) were determined in whole body soft tissue homogenates and in muscles of resident and migratory birds collected from Lake Baikal, Russia. The residue pattern in both resident and migratory birds was in the following order: PCBs > DDTs > HCHs > CHLs. OC concentrations in migratory birds varied, depending on the feeding habit. The maximum levels of OCs were found inpiscivores, followed by insectivores, omnivores, and herbivores. OC residue levels in Lake Baikal birds were lower than those in the Great Lakes region as well as in other lakes in Europe and Japan. Concentrations of HCHs and DDTs in most of the migratory birds collected in the spring were higher than for those collected in the autumn, indicating a notable accumulation in wintering grounds. Compilation and analysis of the available data in fish and birds from Asia suggested that the tropical and subtropical regions in south Asian countries may be a source of pollution for the wintering accumulation of migratory birds from Lake Baikal. Relatively higher compositions of alpha- and gamma-HCH in total HCHs, p,p'-DDT in total DDTs were observed in some migratory species, indicating recent exposure to HCHs and DDTs in Lake Baikal or wintering areas. PCB isomer patterns were different between residents and migrants,with the predominance of lower chlorinated congeners in migratory species, suggesting recent PCB accumulation in stopover sites during wintering. TEQ concentrations of toxic non- and mono-ortho coplanar PCBs in common terns from Lake Baikal were comparable to those reported in some species from Japan, the United States, and Europe. Relative contributions of non-ortho coplanar congeners to toxic equivalents (TEQs) were predominant, in which CB-126 accounted for the highest toxicity contribution. Estimated TEQ concentrations in the common tern from Lake Baikal exceeded the levels associated with enzyme induction in bald eagles. To our knowledge, this is the first comprehensive study showing the seasonal variations of OC accumulation in the birds from Lake Baikal.
  • KQ Sakamoto, T Kunisue, M Watanabe, Y Masuda, H Iwata, S Tanabe, F Akahori, M Ishizuka, A Kazusaka, S Fujita
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 21 (4) 842 - 847 0730-7268 2002/04 [Peer-reviewed]
     Scientific journal 
    Polychlorinated biphenyls (PCBs), including coplanar congeners, hexachlorocyclohexane isomers, chlordane-related compounds, and hexachlorobenzene, were found in the breast muscle of Steller's sea eagles (SSE) and white-tailed sea eagles (WSE) threatened species, collected in Hokkaido, Japan, during the two years from 1998 to 1999. Both PCBs and DDTs were the most notable compounds, with concentrations one to two orders of magnitude higher than the other compounds, that is, from 120 to 39,000 and from 68 to 15,000 ng/g wet weight, respectively. Non-ortho (International Union of Pure and Applied Chemistry [IUPAC] 77, 126, and 169) and mono-ortho (IUPAC 105, 118, and 156)-substituted coplanar PCB congeners amounted to 9.2 to 740 pg/g of 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents derived from the World Health Organization, Paris, France (WHO), toxic equivalent factors. The atmospheric PCBs and DDTs in eastern Siberian cities, such as Khabarovsk and Magadan, have been reported to be much higher than Hokkaido and the North Pacific. Thus, we speculated that the eagles might have been contaminated in these areas, where they spend most of the year except winter, which they spend in eastern Siberia. Adult eagles accumulated more PCBs and DDTs than younger ones. The patterns of PCB congeners were also found to change, depending on the age of the eagle examined; adult eagles showed relatively higher proportions of highly chlorinated PCBs than juvenile eagles did. This difference would be related to the efficiency of the excretion and the metabolism of each PCB congener in the eagles.
  • Chiba, I, A Sakakibara, H Iwata, M Ishizuka, S Tanabe, F Akahori, A Kazusaka, S Fujita
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 21 (4) 794 - 806 0730-7268 2002/04 [Peer-reviewed]
     Scientific journal 
    From 16 largha seats (Phoca largha) and 15 ribbon seals (Phoca fasciata) in the coastal waters of Hokkaido, Japan, blubber chlorinated hydrocarbon (CHC) levels and hepatic cytochrome P450 (CYP) catalytic activities and their immunochemically detected protein content levels were measured. Concentrations of DDTs (2,2-bis(4-chlorophenyl)-1,1-dichloroethylene,p,p'-DDE; 2,2-bis(4-chlorophenyl)-1,1-dichloroethane,p,p'-DDD; dichlorodiphenyltrichloroethane, p,p'-DDT), polychlorinated biphenyl congeners (PCBs), and chlordane compounds (oxychlordane, chlordanes, and nonachlors) in both species were in the range of 290 to 5,300, 420 to 4,000, and 130 to 1,500 ng/g lipid weight, respectively. Aryl hydrocarbon receptor (AhR) agonists, non-ortho (IUPAC 77 and 126) and mono-ortho (IUPAC 105, 118, and 156) coplanar PCB congeners, were also detected, and the 2,3,7,8-tetrachlordibenzo-p-dioxin (TCDD) toxic equivalents (TEQs) were 4.9 to 120 pg TEQ/g lipid weight. Cross-reactive proteins with polyclonal antibodies against rat CYP1A1 and CYP3A2 were notably detected in seal liver microsomes. Interestingly, a polyclonal antibody against rat CYP2B1 recognized proteins only at trace levels. In largha seals, both levels of alkoxyresorufin- (methoxy-, ethoxy-, pentoxy-, and benzyloxyresorufin) O-dealkylase (AROD) activities and proteins detected by polyclonal antibodies against rat CYP1A1 were significantly correlated with the concentrations of individual coplanar PCB congeners, total TEQs, and total PCBs. Threshold concentrations for TEQs in blubber of the largha seal to induce hepatic CYP1A protein and EROD activity were estimated to be 8.5 and 19 pg TEQ/g fat weight, respectively. In ribbon seals, similar correlations were not detected, although the TEQ levels were not significantly lower than those in largha seals. These results suggest that AROD activity and CYP1A1 protein in the liver of the largha seal could be a biomarker for the exposure to AhR agonists such as coplanar PCB congeners. This study also indicates differences in AhR-mediated responses to the CHC exposures between largha and ribbon seals.
  • T Kunito, Watanabe, I, G Yasunaga, Y Fujise, S Tanabe
    MARINE ENVIRONMENTAL RESEARCH 53 (2) 175 - 197 0141-1136 2002/03 [Peer-reviewed]
     Scientific journal 
    Concentrations of 12 trace elements (V, Cr, Mn, Cu, Zn, Se, Rb, Sr, Cd, Cs, Ba, and Hg) were determined in liver and skin tissues of minke whales from various regions within the Antarctic Ocean. Cd concentrations in livers of southern minke whale were apparently higher than those in cetaceans from other regions, while Hg concentrations were lower. There were significant positive correlations between body length and concentrations of Cd and Hg in the liver. The concentrations of all trace elements in the skin were lower than those in other cetaceans reported previously. Significant positive correlations between liver and skin were found for Cr, Mn, Cu, Zn, Rb, Cd, and Cs, implying that the concentrations of these trace elements in the skin reflect those of internal organs. Large interannual variation of the accumulation pattern of trace elements in the skin was observed for the southern minke whales from Area V. There were significant differences in the skin element concentrations among Areas III, IV, and V, especially for males. Also, discriminant analysis between geographically two different groups collected during 1995/1996 austral summer season, based on the concentrations of trace elements in the skin, allowed for a correct classification of 90% of these minke whales. These results suggest that measurement of trace elements in skin samples could provide valuable information on the status of contamination and possible geographic differences in the accumulation levels in southern minke whales. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • APX de Brito, D Ueno, S Takahashi, S Tanabe
    MARINE POLLUTION BULLETIN 44 (2) 172 - 177 0025-326X 2002/02 [Peer-reviewed]
     Scientific journal
  • 渡邉 泉, 四宮基彦, 國頭 恭, 田辺信介, 窪寺恒己
    地球化学 36 (4) 179 - 189 2002 [Peer-reviewed]
  • APX de Brito, S Takahashi, D Ueno, H Iwata, S Tanabe, T Kubodera
    MARINE POLLUTION BULLETIN 45 (1-12) 348 - 361 0025-326X 2002 [Peer-reviewed]
     Scientific journal 
    Organochlorine (OCs) and butyltin (BTs) residues were determined in deep-sea organisms collected from the western North Pacific, off-Tolioku, Japan. Among OCs, concentrations of polychlorinated biphenyls (PCBs') and DDTs (DDTs and its metabolites) were the highest in deep-sea organisms (maximum concentrations of 6700 and 13,000 ng/g lipid wt, respectively). Chlordane compounds (CHLs) were the next most abundant OCs. and hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) were the lowest. BTs were also detected at maximum concentrations of 570 ng/g wet wt. Concentrations of PCBs, CHLs and BTs in deep-sea organisms collected front the western North Pacific, off-Tohoku, were generally lower than those in deep-sea and shallow water organisms from Japanese coastal waters. On the other hand, considerable variations in the concentrations of OCs were found among deep-sea organisms analyzed. Several carnivorous fishes such as snubnosed eel. lanternshark and grenadiers accumulated some OCs such as PCBs, DDTs and CHLs at high concentrations of up to a few mug/g levels. In addition, the residue pattern of OCs and BTs in fishes showed a specific trend according to the sampling depth; higher concentrations of PCBs, DDTs and CHLs and lower concentrations of HCHs, HCB and BTs were found in fishes collected from greater depth (similar to1000 m) compared to those from shallower waters. This trend is consistent with the results of our earlier study on mesopelagic myctophid fishes. Results of this study suggest vertical transport of hydrophobic OCs such as PCBs, DDTs and CHLs and its accumulation in benthic deep-sea organisms. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • D Ueno, H Iwata, S Tanabe, K Ikeda, J Koyama, H Yamada
    MARINE POLLUTION BULLETIN 45 (1-12) 254 - 261 0025-326X 2002 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorines (OCs) such as PCBs, DDTs, chlordanes (CHLs), HCHs and HCB were determined in the liver of bluefin tuna (Thunnus thynnus) collected from Japanese coastal waters in order to elucidate accumulation profiles and to evaluate the suitability of this species as a biomonitor for pollution in the open sea ecosystem. Concentrations of PCBs, DDTs and CHLs in bluefin tuna increased significantly with body length (30-190 cm). HCHs and HCB residues were comparable among all the sampling regions, and the levels of these chemicals did not show correlation with body length. These results suggest significance of dietary uptake of PCBs, DDTs and CHLs compared to the intake via the gill. On the other hand, equilibrium partitioning with ambient water is a major determinant of the levels of HCHs and HCB in tuna. Body-Length Normalized Values (BLNV) of PCBs, DDTs and CHLs concentrations in bluefin tuna were calculated using the linear regression equation obtained from the plot of concentrations and body length. BLNV of these chemicals on a lipid wt basis, which was adjusted for 100 cm body length, were indicative of the present state water pollution by PCBs, DDTs and CHLs. These results suggest that bluefin tuna is a suitable bioindicator for monitoring OCs contamination in the open sea ecosystem. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • J Yang, T Kunito, S Tanabe, M Amano, N Miyazaki
    MARINE POLLUTION BULLETIN 45 (1-12) 230 - 236 0025-326X 2002 [Peer-reviewed]
     Scientific journal 
    Concentrations of Fe, Zn, Cu, Se, Mn, Mo, fig, Cd, Cr, Ag, Pb, Sr and V were determined in skins of Dall's porpoises (Phocoenoides dalli) of the Pacific coast truei-type population (PT population) (N = 45), and the Sea of Japan-Okhotsk dalli-type population (JD population) (N = 31) from the northern waters of Japan. Cutaneous Hg concentrations in both PT and JD populations were significantly correlated with age, indicating a possible alternative method of age estimation. A significant correlation was also noted between Hg concentrations in skin and liver, suggesting that biopsy samples of skin can provide a non-lethal surrogate for monitoring Hg contamination in this species. Trace element accumulation patterns differed strongly between PT and JD populations, when analyzed by principal component analysis, suggesting these patterns could be utilized as non-lethal tracers of population identification. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • Y Anan, T Kunito, H Sakai, S Tanabe
    MARINE POLLUTION BULLETIN 45 (1-12) 224 - 229 0025-326X 2002 [Peer-reviewed]
     Scientific journal 
    Subcellular distribution of Cu, Zn, Se, Rb, Mo, Ag, Cd and Pb was determined in the liver of green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) from Yaeyama Islands, Japan. Also, hepatic cytosol from sea turtles was applied on a Sephadex G-75 column and elution profiles of trace elements were examined. Copper, Zn, Se, Rb, Ag and Cd were largely present in cytosol in the liver of both species, indicating that cytosol was the significant site for the accumulation of these elements in sea turtles. In contrast, Mo and Pb were accumulated specifically in nuclear and mitochondrial fraction and microsomal fraction, respectively. Gel filtration analysis showed that Cu, Zn, Ag and Cd were bound to metallothionein (NIT) in the cytosol of sea turtles. To our knowledge, this is the first report on the association of trace elements with MT in sea turtles. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • R Kubota, T Kunito, S Tanabe
    MARINE POLLUTION BULLETIN 45 (1-12) 218 - 223 0025-326X 2002 [Peer-reviewed]
     Scientific journal 
    Concentrations of total arsenic and individual arsenic compounds were determined in livers of cetaceans (Dall's porpoise and short-finned pilot whale), pinnipeds (harp and ringed seals), sirenian (dugong), and sea turtles (green and loggerhead turtles) to characterize arsenic accumulation profiles in higher trophic marine animals. Hepatic arsenic concentrations in sea turtles were highest among the species examined. Chemical speciation of arsenic revealed that arsenobetaine was the major arsenic compound in almost all the species. In contrast, arsenobetaine was a minor constituent in dugong. Dimethylarsinic acid, methylarsonic acid, arsenocholine, tetramethylarsonium ion, arsenite, and an unidentified arsenic compound were also detected as minor constituents. However, the composition of arsenic compounds was different among these species. These results might reflect the differences in the metabolism of arsenic and/or the compositions of arsenic compounds in their preys. To our knowledge, this is the first report on the large variation in the composition of arsenic species in liver of marine mammals and sea turtles. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • H Nakata, A Sakakibara, M Kanoh, S Kudo, H Watanabe, N Nagai, N Miyazaki, Y Asano, S Tanabe
    ENVIRONMENTAL POLLUTION 120 (2) 245 - 253 0269-7491 2002 [Peer-reviewed]
     Scientific journal 
    The effects or exposure to butyltin compounds (BTs: tributyltin; TBT, dibutyltin; DBT and monobutyltin; MBT) and non-ortho coplanar PCBS (IUPAC 77, 126 and 169) oil marine mammals and human lymphocyte were evaluated. Peripheral blood mononuclear cells (PBMCs) isolated from Dall's porpoises (Phocoenoides dalli), bottlenose dolphins (Tursiops truncatus), a California scalion (Zalophus californianus), a larga seal (Phoca largha) and humans (Homo sapiens) were exposed at varying concentrations of BTs and coplanar PCBs. Concanavalin A (Con A)-stimulated mitogenesis found significantly suppressed (P<0.01) when the cells were exposed at 300 nM (89 ng/ml) of TBT and 330 nM of DBT (77 ng/ml), while NOT showed little cytotoxicity at treatment levels of up to 3600 nM (620 ng/ml). BTs concentrations in the liver of Dall's porpoises from Japanese coastal waters ranged between 81-450 ng/g for TBT and 200-1100 ng/g (wet m.) for DBTs, which is greater than the cytotoxic levels registered in this study. In contrast, non-ortho coplanar PCBs did not suppress cell proliferation at concentrations of up to 30 nM (10 ng/ml). The residue levels of coplanar PCBs in the blubber of Dall's porpoises were 0.12-1.3 ng/g, which were one order of lower than those levels that do cell proliferation. When cells were exposed to a mixture of TBT/DBT and coplanar PCBs, the proliferation was significantly reduced to 33 nM DBT plus 34 nM CB-77 and 33 nM DBT plus 28 nM CB-169 mixtures. respectively. The investigations relating the contaminant-induced immunosuppression in marine mammals have been focused on persistent organochlorines such as PCBs, pesticides and dioxin Compounds. However, this study suggested the possibility of BTs could also pose a serious threat to the immune functions in free-ranging marine mammals and humans. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • Taisen Iguchi, Manabu Sumi, Shinsuke Tanabe
    Congenital anomalies 42 (2) 106 - 119 0914-3505 2002 [Peer-reviewed]
     
    Monitoring of environmental chemicals in Japan has revealed that several endocrine active chemicals are in river water, sediments, and wildlife as well as in the human umbilical cord. In 2001, risk assessments of tributyltin and nonylphenol have been conducted by the Ministry of the Environment, Japan. Risk assessments of di(2-ethylhexyl)phthalate and di-isononyl phthalate have also been performed by the Ministry of Health, Labour and Welfare using a toxicological point of view in 2001. In this review, an overview of recent progress in endocrine disruptor research in Japan will be provided.
  • APX de Brito, D Ueno, S Takahashi, S Tanabe
    CHEMOSPHERE 46 (3) 401 - 411 0045-6535 2002/01 [Peer-reviewed]
     Scientific journal 
    Persistent organochlorine (OC) and toxic butyltin compounds (BTs) were determined in walleye pollock (Theragra chalcogramma) collected from Gulf of Alaska, Bering Sea and Japan Sea, during 1991 and 1992. Polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDTs) and its metabolites were the most abundant compounds ranging up to 3200 and 2500 ng/g on lipid weight, respectively, followed by chlordane compounds (CHLs), hexachlorocyclohexane isomers (HCHs) and hexachloro benzene (HCB) in the liver of walleye pollock. Concentrations of HCHs and HCB in walleye pollock from these remote areas were higher than those in fishes from the western North Pacific and Japanese coastal waters, indicating atmospheric transport of these compounds to higher latitude regions such as Bering Sea and Gulf of Alaska and/or local input around northern Japan Sea. The concentrations of other OCs were generally comparable to those in fishes from North Pacific Ocean and Japanese waters but significantly lower than in cod-like fishes from North Atlantic and European countries. Among sampling locations, walleye pollock from Japan Sea showed higher concentrations of DDTs and HCHs compared to fishes from Bering Sea and Gulf of Alaska, suggesting greater input of these compounds around Japan Sea. Slower declining trend of DDTs and CHLs and an increasing pattern of PCBs concentrations were found in walleye pollock from Bering Sea during 1982-1992. This may imply a continuous input of these compounds by long-range transport and/or long-term persistency in these cold regions. Compared to the fishes from Japan Sea, walleye pollock from Bering Sea and Gulf of Alaska showed higher proportions of alpha-HCH and p,p'-DDE in the composition of HCH isomers and DDT compounds, respectively. This suggests selective transportability of these compounds during long-range transport to higher latitude remote areas. Concentrations of tributyltin (TBT) in the muscle of walleye pollock ranged from 1.1 to 5.5 ng/g on wet weight. Concentrations of TBT in deep-sea walleye pollock from Gulf of Alaska and Bering Sea were lower than those in Japan Sea. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • M Ohji, Takeuchi, I, S Takahashi, S Tanabe, N Miyazaki
    MARINE POLLUTION BULLETIN 44 (1) 16 - 24 0025-326X 2002/01 [Peer-reviewed]
     Scientific journal 
    Tests for the acute toxicity of tributyltin (TBT) were conducted on amphipod crustaceans collected from Otsuchi Bay, Japan. Five species of caprellids and three species of gammarids, which belong to a closely related ecological niche, were used for the exposure experiments at seven test concentrations (0, 0.001, 0.01, 0.1, 1, 10 and 100 mug TBTCl/l) for 48 h at 20degreesC. The 48-h LC50 values of the caprellids were 1.2-6.6 mug TBTCl/l, and these were significantly lower than those of the gammarids (17.8-23.1 mug TBTCl/l). This suggests that caprellids are more sensitive to TBT than gammarids. Furthermore, the proportions of TBT and its derivatives, dibutyltin (DBT) and monobutyltin (MBT), were measured in the amphipods collected from Otsuchi Bay. In the caprellids, TBT was the predominant compound. accounting for 72% of the total butyltin which reflected the butyltin ratio in seawater, while in the gammarids, TBT's breakdown products (DBT and MBT) predominated, accounting for 75% of the total butyltin. This difference suggests that caprellids may have lower metabolic capacity to degrade TBT than gammarids. Therefore, the difference in sensitivity to TBT among the amphipods is thought to be related to the species-specific capacity to metabolize TBT. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • HK Hong, S Takahashi, BY Min, S Tanabe
    ENVIRONMENTAL POLLUTION 117 (3) 475 - 486 0269-7491 2002 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (BTs) including tributyltin (TBT) and its degradation products, di- (DBT) and mono-butyltin (MBT), were determined in bivalves such as blue mussels (Mytilus edulis) and arkshells (Scapharca broughtonii) collected from Korean coastal waters. BTs were detected in all the blue mussels and arkshells analyzed. The concentrations of total butyltin (SigmaBTs: MBT + DBT + TBT) in blue mussels and arkshells ranged from 49 to 2500 ng/g and 29 to 87 ng/g wet weight, respectively. Higher concentrations of BTs were found in blue mussels collected from Okpo and Kohyonsong Bays and Jangsengpo Harbor where large shipyards and harbors are located with dry-dock facilities. This suggested that maritime activities nearby the harbors play a major role as the source of BTs. Concentrations of TBT in mussels collected from Korea were one of the highest values reported, suggesting ongoing TBT contamination in Korea. Among BTs, TBT was the predominant compound both in blue mussels and arkshells collected from almost all the sampling locations, indicating the fresh input of TBT in Korean coastal waters. Smaller mussels tended to accumulate BTs at higher concentrations than larger ones, which may be due to higher filtration rate of small mussels and/or contact with surface microlayer in intertidal zones. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • N Kajiwara, S Niimi, M Watanabe, Y Ito, S Takahashi, S Tanabe, LS Khuraskin, N Miyazaki
    ENVIRONMENTAL POLLUTION 117 (3) 391 - 402 0269-7491 2002 [Peer-reviewed]
     Scientific journal 
    Polychlorinated biphenyls (PCBs), organochlorine pesticides and organotin compounds were determined in the blubber and liver of Caspian seals (Phoca caspica) found stranded on the coast of the Caspian Sea during an outbreak of canine distemper virus (CDV) in 2000. Among organochlorines analyzed, DDTs were the most dominant contaminants with concentrations ranging from 6.3 to 470 mug/g on a lipid-weight basis. Caspian seals collected in 2000 during the epizootic had higher concentrations of organochlorines than healthy individuals sampled in 1998. However, the blubber layer was generally thinner in the seals collected in 2000 than those in the previous surveys. Although compositions of organochlorine pesticides in seals suggested that the contamination status in the Caspian Sea is improving, the levels found in Caspian seals in 2000 were comparable to those in other marine mammals that have suffered from epizootics. This implies that the present status of contamination found in Caspian seals poses a risk of immunosuppression. Concentrations of butyltin compounds in livers of seals ranged from 0.49 to 17 ng/g on a wet-weight basis and octyltin compounds were below limit of detection in all the samples analyzed, suggesting less contamination by organotin compounds in the Caspian Sea. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • Y Anan, T Kunito, Watanabe, I, H Sakai, S Tanabe
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 20 (12) 2802 - 2814 0730-7268 2001/12 [Peer-reviewed]
     Scientific journal 
    Concentrations of 18 trace elements (V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Zr, Mo, Ag, Cd, Sb, Ba, Hg, TI, and Pb) were determined in the liver, kidney, and muscle of green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) from Yaeyama Islands, Okinawa, Japan. Accumulation features of trace elements in the three tissues were similar between green and hawksbill turtles. No gender differences in trace element accumulation in liver and kidney were found for most of the elements. Significant growth-dependent variations were found in concentrations of some elements in tissues of green and hawksbill turtles. Significant negative correlations (p < 0.05) were found between standard carapace length (SCL) and the concentrations of Cu, Zn, and Se in the kidney and V in muscle of green turtles and Mn in the liver, Rb and Ag in kidney, and Hg in muscle of hawksbill turtles. Concentrations of Sr, Mo, Ag, Sb, and TI in the liver, Sb in kidney, and Sb and Ba in muscle of green turtles and Se and Hg in the liver and Co. Se, and Hg in kidney of hawksbill turtles increased with an increase in SCL (p < 0.05). Green and hawksbill turtles accumulated extremely high concentrations of Cu in the liver and Cd in kidney, whereas the levels of Hg in liver were low in comparison with those of other higher-trophic-level marine animals. High accumulation of Ag in the liver of green turtles was also observed. To evaluate the trophic transfer of trace elements, concentrations of trace elements were determined in stomach contents of green and hawksbill turtles. A remarkably high trophic transfer coefficient was found for Ag and Cd in green turtles and for Cd and Hg in hawksbill turtles.
  • TB Minh, M Watanabe, S Tanabe, T Yamada, J Hata, S Watanabe
    ENVIRONMENTAL HEALTH PERSPECTIVES 109 (9) 927 - 935 0091-6765 2001/09 [Peer-reviewed]
     Scientific journal 
    We examined human adipose tissue, liver, and bile from humans in Japan to understand the contamination status, specific accumulation, and elimination of two newly identified environmental contaminants, tris(4-chlorophenyl) methane (TCPMe), tris (4-chlorophenyl) methanol (TCPMOH), and other persistent organochlorines such as polychlorinated biphenyls (PCBs), DDT and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), and chlordane compounds (CHLs). TCPMe and TCPMOH concentrations in Japanese human adipose tissue were slightly higher than those reported previously, indicating widespread exposure to these compounds in humans. Elevated residues of PCBs and DDTs are found in adipose tissue and liver. Concentrations in bile strongly correlated with concentrations in adipose fat and Ever, which may suggest an equilibration in adipose fat/bile and liver/bile and possible biliary excretion of persistent organochlorines in humans. Composition of the organochlorines accumulated further indicates a metabolic capacity in humans higher than that of marine mammals. We observed age-dependent accumulation for TCPMe, TCPMOH, and other organochlorines, but there were no significant gender differences. p,p'-DDE and TCPMe were estimated to have low biliary excretion rate. Elimination potential of persistent organochlorines may be related to their octanol-water partition coefficient. The relationship between excretion rate and octanol-water partition coefficient may be used to predict the biliary excretion potential of some other lipophilic organochlorines such as dioxins and dibenzofurans in humans. The presence of organochlorines in bile suggests that the hepatic excretory system plays a major role in the elimination of xenobiotics in humans. To our knowledge, this is the first study of accumulation and elimination of TCPMe and TCPMOH in humans.
  • KS Guruge, H Tanaka, S Tanabe
    MARINE ENVIRONMENTAL RESEARCH 52 (3) 271 - 288 0141-1136 2001/09 [Peer-reviewed]
     Scientific journal 
    Concentrations of PCBs and their toxic potential were examined in subcutaneous fat of eight albatross and one petrel species collected from the North Pacific and the Southern Oceans. Among all the species analyzed, high PCB levels were found in adult mate black-footed albatross from the North Pacific with the mean value of 92 mug/g wet weight. No significant gender difference in PCB accumulation was observed (P > 0.1). The mean PCB levels in Southern Oceanic birds were 1 or 2 orders of magnitude lower than those from the North Pacific albatrosses. A regional-specific accumulation of non-ortho coplanar congeners were observed, most birds from the Southern Ocean had higher IUPAC 169 levels while IUPAC 126 concentrations were higher in those from the North Pacific. The estimated toxic equivalents for black-footed and Laysan albatrosses from the North Pacific were in the same range of some fish-eating birds, which were highly contaminated by PCBs. The correlation between ratio of IUPAC 169/126 concentration and total PCBs concentration indicated the possibility of induction in cytochrome P450 activities in North Pacific albatrosses (P < 0.01). The calculated hazard indices indicated that black-footed and Laysan albatrosses inhabiting in the North Pacific had similar threshold levels which were known to cause toxic effects in some populations of fish-eating birds. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • D Ueno, S Takahashi, S Tanabe, K Ikeda, J Koyama, H Yamada
    NIPPON SUISAN GAKKAISHI 67 (5) 887 - 893 0021-5392 2001/09 [Peer-reviewed]
     Scientific journal 
    Live speciments of the blue mussel Mytilus galloprovincialis were collected from the southwestern coastal region of Tokyo Bay and examined for seasonal, size-dependent and spatial variations in the concentrations of organochlorine compounds (OCs) such as PCBs (polychlorinated biphenyls), DDTs (DDT and its metabolites), CHLs (chlordane and related compounds), HCHs (hexachlorocyclohexane isomers) and HCB (hexachlorobenzene), Seasonal variations in OCs concentrations (fat weight base) appeared to reflect the levels in an ambient water rather than seasonal physiological changes of mussels. Neither shell size nor vertical habitation of mussels resulted in significant differences in their concentrations (fat weight base). These results suggest that the variable factors examined did not significantly affect the availability and suitability of mussels as bioindicators for monitoring of contamination with OCs.
  • A Takeuchi, S Takahashi, S Tanabe, N Miyazaki
    MARINE ENVIRONMENTAL RESEARCH 52 (2) 97 - 113 0141-1136 2001/08 [Peer-reviewed]
     Scientific journal 
    A comparative study on the butyltin levels in various organisms showed that marked bioaccumulation occurs in certain lower trophic levels; i.e. from seawater to phytoplankton and into caprellid amphipods, Caprella spp. Caprella spp., which inhabit al.-al communities and aquaculture beds in the subtidal zone, are small crustaceans with reduced movement and a life-span of less than 3 months. These characteristics indicate that Caprella spp. may be well-suited for monitoring butyltin residue changes over small spatial and temporal scales. Two groups of organisms, mussels and neogastropods, have been mainly used for monitoring butyltin in shallow water ecosystems. These invertebrates mainly inhabit the intertidal zone where the butyltin levels vary widely depending on the immersion period and exposure to the sea surface microlayer. Monitoring using neogastropods may also over estimate exposures after restrictions on tributyltin, since neogastropods show an irreversible response to residue changes owing to their long life-spans. Thus, we propose usage of Caprella spp. to monitor temporal and spatial changes in baseline concentrations of butyltins. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • N Kajiwara, K Kannan, M Muraoka, M Watanabe, S Takahashi, F Gulland, H Olsen, AL Blankenship, PD Jones, S Tanabe, JP Giesy
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 41 (1) 90 - 99 0090-4341 2001/07 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated biphenyls (PCBs), DDTs (p,p ' -DDE, p,p ' -DDD, p,p ' -DDT), chlordanes (CHLs; cis-chlordane, cis-nonachlor, trans-nonachlor, and oxychlordane), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), tris(4-chlorophenyl)methane (TCPMe), tris(4-chlorophenyl)methanol (TCPMOH), and mono- (MBT), di-(DBT), and tri-butyltin (TBT) were determined in blubber and livers of 15 California sea lions (Zalophus californianus), 6 northern elephant seals (Mirounga augustirostris), and 10 harbor seals (Phoca vitulina) found stranded along the coasts of California, USA, during 1991-1997. Among the organochlorines analyzed, DDTs were predominant, followed in decreasing order by PCBs, CHLs, TCPMe, TCPMOH, HCHs, and HCB. The greatest concentrations of organochlorines were found in California sea lions. The highest DDT and PCB concentrations found in the blubber of California sea lions were 2,900 and 1,300 mug/g, lipid weight, respectively. Concentrations of TCPMe and TCPMOH in California sea lions were correlated significantly with DDT concentrations. Concentration ratios of various organochlorines in harbor seal livers were different from those in California sea lions and elephant seals, which suggested that the sources of exposure of harbor seals to organochlorines were different from those in the other two species. Concentrations of butyltin compounds in livers of pinniped species ranged from 2 to 99 ng/g, wet weight, which were less than those observed in cetaceans and in California sea otters.
  • Chiba, I, A Sakakibara, Y Goto, T Isono, Y Yamamoto, H Iwata, S Tanabe, K Shimazaki, F Akahori, A Kazusaka, S Fujita
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 20 (5) 1092 - 1097 0730-7268 2001/05 [Peer-reviewed]
     Scientific journal 
    Chlorinated hydrocarbon (CHC) levels in the blubber of larga seals (Phoca largha) and ribbon seals (Phoca fasciata) collected from the coastal waters of Hokkaido, Japan, were determined in order to assess the hormonal effects of CHC exposure in free-ranging pinnipeds. Plasma thyroid hormone levels, including total thyroxine (T4), free thyroxine (free T4), total triiodothyronine (T3), and free triiodothyronine (free T3), were also measured. Higher concentrations of polychlorinated biphenyl congeners (PCBs), dichlorodiphenyltrichloroethane and its metabolites, and chlordane compounds were found in the range of 380 to 2,600 ng/g, 350 to 2,600 ng/g, and 120 to 760 ng/g on a wet-weight basis, respectively. Spearman rank correlation analyses showed that in larga seals, plasma total T3 and free T3 levels negatively correlated with levels of all the CHCs analyzed, although there was no such correlation between total or free T4 levels and CHC concentrations. In ribbon seals, total T3 levels significantly decreased with an increase of di-ortho PCB (PCB 170 and 180) residues. These findings indicated that the plasma T3 deficiency could be associated with some CHC exposure in larga and ribbon seals and that the responses of plasma thyroid hormones may be useful biomarkers for CHC exposure in ribbon seals.
  • KT Lee, S Tanabe, CH Koh
    MARINE POLLUTION BULLETIN 42 (4) 273 - 279 0025-326X 2001/04 [Peer-reviewed]
     Scientific journal 
    To elucidate the characteristic distribution and contamination of polychlorinated biphenyls (PCBs) in sediments, 63 sediments and five benthic organisms from Kyeonggi Bay, Namyang Bay and Lake Shihwa, West coast of Iio;ka, mere analysed. Characterization of PCBs distribution in sediments was conducted by correlation between PCBs concentrations and environmental parameters, comparison of contamination level and composition of PCBs homologs between Kanechlor mixture (KC-mix) and sediments. The residues of PCBs in sediments were correlated with total organic carbon (TOC) and particulate organic carbon (POC) contents, not with mud contents and grain size distributions. Elevated concentrations of T-PCBs mere found in sediments from Incheon North Harbor (INH) in Kyeonggi Bay. T-PCBs concentrations were decreased with distance increase from inner site of INH, The residues of T-PCBs in sediments from Namyang Bay were either non-detectable or near to detection limit. I(le contamination ba; PCBs in sediments from Lake Shihwa was also low, The PCBs congener profiles in INH R ere similar to those of KC-mis, while those in less contaminated sites showed relatively high percentage of lower chlorinated biphenyls. Sites K18 (580 ng/g or 48 ug/g-OC dry wt) and K19 (330 ng/g or 38 ug/g-OC dry wt) within INH exceeded the sediment quality criteria (SQC) (16 mug/g-OC as a KC-mix) derived from equilibrium partitioning (EqP) approach. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • KS Guruge, S Tanabe
    MARINE POLLUTION BULLETIN 42 (3) 179 - 186 0025-326X 2001/03 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), isomers of hexachlorocyclohexane (HCHs), hexachlorobenzene (HCB), chlordane compounds (CHLs) and butyltin compounds (mono-, di- and tributyltin) were determined in biota and sediments collected from locations on the west coast of Sri Lanka, The PCB concentrations found in fish from the Kelani River mouth were higher than those from other Asian developing countries. The pattern of organochlorine accumulation was in the order of PCBs > DDTs > CHLs > HCHs > HCB, and resembled those reported for most developed countries, The accumulation pattern of butyltins in fish was in the order of TBT > DBT > MBT suggesting recent exposure to TBT sources. Total butyltin concentrations found in rabbit fish liver (11-38 mug/g wet wt), collected from the Colombo dockyard, could be the highest ever reported for fish in the world. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • R Kubota, T Kunito, S Tanabe
    ENVIRONMENTAL POLLUTION 115 (2) 303 - 312 0269-7491 2001 [Peer-reviewed]
     Scientific journal 
    Arsenic concentrations were determined in livers of 226 individuals representing 16 different marine mammal species to elucidate its accumulation with age, sex, and feeding habits. Arsenic concentrations varied widely among species and individuals, and ranged from < 0.10 to 7.68 mug g(-1) dry weight. Marine mammals feeding on cephalopods and crustaceans contained higher arsenic concentrations than those feeding on fishes. No significant gender difference in arsenic concentration was found for almost all the species. Also, no apparent trend with age (or body length) in arsenic accumulation was found for most of the species. It was noted that two seal species, Baikal seal and Caspian seal, from landlocked water environments, contained lower arsenic concentrations than the marine species. To our knowledge, this is the first comprehensive study of arsenic accumulation in a wide range of marine mammal species. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • KS Guruge, M Watanabe, H Tanaka, S Tanabe
    ENVIRONMENTAL POLLUTION 114 (3) 389 - 398 0269-7491 2001 [Peer-reviewed]
     Scientific journal 
    Current status of contamination by persistent organochlorines (OCs) such as polychlorinated biphenyles (PCBs), dichloro-diphenyl trichloroethane and its metabolites (DDTs), isomers of hexachlorocyclohexane (HCHs), hexachlorobenzene (HCB) and chlordane compounds (CHLs) were examined in 61 individuals belonging to eight albatross species collected from the North Pacific and the Southern Ocean. Generally high OC concentrations were found in albatrosses from the North Pacific than those from the Southern Oceans. Black-footed albatrosses had noticeably high PCBs and DDTs concentrations with mean values of 92 and 33 mug/g wet weight in subcutaneous fat, respectively. Among the other OCs, concentration of CHLs was higher than that of HCB in North Pacific albatrosses. HCHs accumulation was the lowest among all the OCs analyzed. Species-specific differences were observed for HCB, CHLs and DDTs in some species in the Southern Ocean. No significant difference of gender and age-related accumulation was observed in total OCs. However, PCB concentrations were higher in mature birds than those from immature ones in the Southern Ocean. Species-specific accumulation patterns of OCs in albatrosses were closely related with their feeding, migration, age and geographical ranges. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • KT Lee, S Tanabe, CH Koh
    ENVIRONMENTAL POLLUTION 114 (2) 207 - 213 0269-7491 2001 [Peer-reviewed]
     Scientific journal 
    The residues of oragnochlorine pesticides (OCPs) in 62 sediments from Kyeonggi Bay and nearby areas in the west coast of Korea were determined. The concentrations of chlordanes (CHLs) and DDTs showed a distinctive gradient of contamination between inner and outer sites of Incheon North Harbor (INH), whereas hexachlorocyclohexanes (HCHs) were uniformly distributed at most sites studied. The distribution of CHLs and DDTs was strongly correlated with total organic carbon contents in sediments while HCH residue levels were independent. Relationship between contaminant's concentration and environmental factors was analyzed by principal component analysis. Distribution patterns of T-CHLs, T-DDTs, and TOC were similar while those of T-HCHs, mud content, and grain size were similar. The notable contamination by CHLs and DDTs was found in INH where these levels were one or two orders of magnitude higher than other sites. The dominant OCPs in sediments were P-HCH among HCH compounds, trans-chlordane among CHL compounds, and pp'-DDD among DDT compounds. The higher concentrations and compositional pattern of OCPs in INH sediments indicate that INH is in the vicinity of the source. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • K Senthilkumar, K Kannan, A Subramanian, S Tanabe
    ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 8 (1) 35 - 47 0944-1344 2001 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated biphenyls (PCBs), DDT and its metabolites (DDTs), HCH isomers (HCHs), chlordane compounds (CHLs) and hexachlorobenzene (HCB) were determined in sediment, soil, whole body homogenates of resident and migratory birds and their prey items (including fish, green mussel, snail, earthworm, crabs, prawn, lizard and frogs), bird eggs and bats collected from southern India during 1995 and 1998. Accumulation pattern of organochlorines (OCs) in biota was, in general, in the order, HCHs > DDTs > PCBs > CHLs=HCB. Magnitude of OC concentrations increased in the order of sediments < green mussel < earthworm < frog < lizard < fish < bird egg < bats < birds tissues. Biomagnification features of OCs were examined in resident and migrant birds to evaluate the exposure levels of these chemicals in wintering grounds of migrant birds. Accumulation of DDTs in migratory birds during wintering in India may be of concern due to the great biomagnification potential of DDTs. Eggs of some resident species contained noticeable concentrations of OCs. Concentrations of OCs in three species of bats analyzed in this study were lower than that found in passerine birds. In addition to OCs, butyltin compounds were also detected at low concentrations in bats.
  • S Takahashi, S Tanabe, K Kawaguchi
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 34 (24) 5129 - 5136 0013-936X 2000/12 [Peer-reviewed]
     Scientific journal 
    Organochlorine (OCs) and butyltin (BTs) residues were determined in mesopelagic myctophid fishes collected from the western North Pacific to elucidate contamination status, accumulation patterns, and distribution. Among OCs, concentrations of PCBs (polychlorinated biphenyls) and DDTs (DDT and its metabolites) were the highest in myctophids (at maximum concentrations bf 370 ng/g and 280 ng/g lipid wt, respectively). CHLs (chlordane compounds) or HCHs (hexachlorocyclohexanes) were the next most abundant OCs, and HCB (hexachlorobenzene) was the lowest. The maximum concentration of total butyltin (Sigma BTs = MBT + DBT + TBT) in fish was 46 ng/g wet wt. Concentrations of PCBs, CHLs, and BTs were significantly lower in oceanic myctophids than those in fishes from Japanese coastal water, Suruga Bay. The residue pattern of OCs and BTs showed a specific trend according to diel vertical migration of myctophids. Relatively high concentrations of PCBs, DDTs, and CHLs were found in nonmigratory species living in deeper waters, whereas concentrations of HCHs, HCB, and BTs were high in migratory species, which migrate up to the upper 200 m at night for feeding. These patterns are also influenced by the vertical distributions of OCs and BTs in the subarctic and transitional waters of the western North Pacific, where intrusion of watermass from the Okhotsk Sea has been suggested. Temporal variation in the residue level and composition of OCs found in myctophids indicated a significant decrease in the input of DDTs into the marine environment while HCHs declined at a slower rate.
  • Teramitsu, I, Y Yamamoto, Chiba, I, H Iwata, S Tanabe, Y Fujise, A Kazusaka, F Akahori, S Fujita
    AQUATIC TOXICOLOGY 51 (2) 145 - 153 0166-445X 2000/12 [Peer-reviewed]
     Scientific journal 
    Marine mammals, being endangered by the chronic exposure of hydrophobic environmental contaminants as an asserting result of global pollution, are especially focused as indicators for organochlorine pollution. The use of contaminant-induced xenobiotic metabolizers, particularly P450 (CYP) 1A, in marine mammals can be effective as potential biomarkers of the contaminant exposure and/or toxic effects. In this study, we identified the first marine mammalian CYPs. Six novel CYP1A cDNA fragments were cloned from the livers of marine mammal species, minke whale (Balaenoptera acutorostrata), dall's porpoise (Phocoenoides dalli), steller sea lion (Eumetopias jubatus), largha seal (Phoca largha), and ribbon seal (Phoca fasciata) by the method of reverse transcription/polymerase chain reaction (RT/PCR); two distinct fragments were from steller sea lion and one fragment each was obtained from the other species. Five of the fragments, one from each species, were classified in the subfamily of CYP1A1, and the other fragment cloned from steller sea lion was designated CYP1A2. Degenerate PCR primers were used to amplify the fragments from liver cDNAs. The deduced amino acid sequences of these fragment CYP1As showed identities ranging from 50.0 to 94.3% with other known vertebrate CYPs in the subfamily of CYP1A, including those from fish, chicken, and terrestrial mammals. The isolated fragments were used to construct a molecular phylogeny, along with other vertebrate CYP1A cDNAs cut down in size to the corresponding region of 265 bp in which those newly determined fragments were cloned. This phylogenetic analysis by the maximum parsimony method using the PHYLIP program suggests two distinct evolutional pathways for aquatic mammalian CYP1As, compatible to a conservative taxonomy. Pinniped genes are clustered together with dog gene, forming a carnivore group, and cetaceans form another branch. Identification of CYP1A genes in marine mammals will be an introductory step to provide new insights into the metabolic or toxicological functions of CYP1As in these animals. (C) 2000 Elsevier Science B.V. All rights reserved.
  • Saeki, K, Sakakibara, H, Sakai, H, Kunito, T, Tanabe, S
    BioMetals 3 241 - 250 2000/09 [Peer-reviewed]
  • H Sakai, K Saeki, H Ichihashi, H Suganuma, S Tanabe, R Tatsukawa
    MARINE POLLUTION BULLETIN 40 (8) 701 - 709 0025-326X 2000/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of heavy metals (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Co and Hg) were determined in tissues and organs of loggerhead (Caretta caretta) and green turtles (Chelonia mydas) collected from Japanese coastal waters, in order to elucidate body distribution and to develop a non-lethal monitoring technique using the carapace, A majority of the metal burdens was present in the muscle, liver, bone and carapace of sea turtles. High Cu concentrations exceeding 10 mu g/g wet wt were observed in the liver of these two turtle species. Mean Zn concentrations in fat tissues of loggerhead and green turtles were 94.6 and 51.3 mu g/g wet wt respectively, which were about 10-fold higher than those reported in other marine animals, Concentrations of Mn, Zn and Hg in the carapace were correlated with whole body burdens, indicating that the carapace is a useful non-lethal indicator for monitoring heavy metal levels in the body of the sea turtle. (C) 2000 Elsevier Science Ltd. All rights reserved.
  • TB Minh, M Watanabe, S Tanabe, T Yamada, J Hata, S Watanabe
    ENVIRONMENTAL HEALTH PERSPECTIVES 108 (7) 599 - 603 0091-6765 2000/07 [Peer-reviewed]
     Scientific journal 
    Tris(4-chlorophenyl)methane (TCPMe) and tris(4-chlorophenyl)methanol (TCPMOH) are among the most recently identified environmental contaminants. Despite their widespread contamination in the marine environment, human exposure to these compounds remains relatively unknown. We determined the concentrations of TCPMe, TCPMOH, and other persistent organochlorines such as polychlorinated biphenyls (PCBs), DDT and its metabolites, hexachlorocyclohexane isomers, hexachlorobenzene, and chlordane compounds (CHLs) in human adipose tissue from Japan. TCPMe and TCPMOH were detected in all of the adipose samples analyzed; the concentrations ranged from 2.5-21 and 1.1-18 ng/g lipid weight, respectively. Concentrations of TCPMe and TCPMOH in humans were less than those reported in marine mammals, suggesting the possibility of metabolism and elimination of these compounds by humans. Significant correlation between TCPMe and TCPMOH with concentrations of DDT and its metabolites in human adipose tissues suggested that exposure to DDT is the source of TCPMe and TCPMOH in humans. The age- and sex-dependent accumulation of TCPMe and TCPMOH as well as other organochlorines was less pronounced. Results for other organochlorines indicated that recent contamination status of PCBs in human samples from Japan was higher than that in developing countries, whereas DDT contamination is lower. Greater concentrations of CHLs in human adipose tissue from Japan than in those from other countries suggest that continuous monitoring of CHLs in humans in Japan is necessary. To our knowledge, this is the first study on the accumulation of TCPMe and TCPMOH in human adipose tissue.
  • D Muir, F Riget, M Cleemann, J Skaare, L Kleivane, H Nakata, R Dietz, T Severinsen, S Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 34 (12) 2431 - 2438 0013-936X 2000/06 [Peer-reviewed]
     Scientific journal 
    Geographical trends in levels of Sigma PCB10 (sum of 10 major congeners), hexachlorocyclohexanes (HCH), Sigma DDT (sum of DDT-related compounds), and other persistent organochlorines (OCs) in ringed seal blubber were examined at 13 sampling locations in the Arctic over 175 deg longitude from northern Canada to the South Kara Sea (Yenisey Gulf) in Russia. Concentrations of OCs were adjusted, using analysis of covariance, for effects of the covariates, sex, age, and blubber thickness. Adjusted mean concentrations of Sigma PCB10 and Sigma DDT were significantly higher in the samples from the Yenisey Gulf in the Russian Arctic, Svalbard, and East Greenland than in west Greenland or the Canadian Arctic. Sigma PCB10 and Sigma DDT in Yenisey Gulf samples were 8x and 6x higher, respectively, than the average in levels from four Canadian locations. Sigma PCB10 and Sigma DDT means declined significantly with increasing westerly longitude (r(2) = 0.75 and 0.73, respectively). Sigma HCH levels for sites in the Canadian Arctic were significantly higher than those from west Greenland (Qeqertarsuaq), east Greenland (Ittoqqortoormiit), and Svalbard and increased significantly from east to west. The geographical trend Sigma HCH is in general agreement with observed trends of HCH in seawater where higher levels have been found in the Canadian Arctic. Higher proportions of more recalcitrant hexa- and pentachloro-PCB congeners were observed in seal blubber samples in the European/Russian Arctic. The continued use of PCBs in electrical equipment and other applications in Russia is a likely source of the more highly chlorinated congeners.
  • M Watanabe, K Kannan, A Takahashi, BG Loganathan, DK Odell, S Tanabe, JP Giesy
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 19 (6) 1566 - 1574 0730-7268 2000/06 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated biphenyl congeners (PCBs) and organochlorine pesticides were determined in the livers of bottlenose dolphins, Atlantic spotted dolphins, and pygmy sperm whales found stranded along the coastal waters of Florida, USA, during 1989 to 1994. The PCBs were the most predominant contaminants followed in order by DDTs, chlordanes, tris(4-chlorophenyl)methane (TCPMe), tris(4-chlorophenyl)methanol (TCPMOH), hexachlorobenzene, and hexachlotocyclohexane isomers. Among the cetaceans analyzed, organochlorine concentrations were greatest in bottlenose dolphins followed by Atlantic spotted dolphins and pygmy sperm whales. Hexa- and heptachlorobiphenyls were the predominant PCB congeners found in the livers of dolphins. Patterns of relative concentrations of PCB congeners varied among individual bottlenose dolphins. A few individuals contained predominant concentrations of octa- (CB-199, 196/201) and nonachlorobiphenyl (CB-206, 208) congeners, which suggested exposure to the highly chlorinated PCB formulation, Aroclor((R)) 1268, a contaminant at a coastal site in Georgia bordering northern Florida. The estimated 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) of coplanar PCBs in bottlenose dolphins were 170 to 18,000 pg/g, lipid weight (mean: 5,400 pg/g) with mono-ortho congeners 118, 105, and 156 contributing more than 80% of the TEQs. The ratios of CB-169 to CB-126 in cetacean livers were linearly related to total PCB concentrations, which suggested a strong induction of microsomal monooxygenase enzymes in the liver. The hepatic concentrations of TCPMe and TCPMOH in bottlenose dolphins and Atlantic spotted dolphins were greater than those in the blubber of marine mammals of various regions, which suggested the presence of sources for these chemicals along the Atlantic coast of Florida.
  • KS Guruge, S Tanabe, M Fukuda
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 38 (4) 509 - 521 0090-4341 2000/05 [Peer-reviewed]
     Scientific journal 
    Common cormorants collected from three colonies and their fish diet were analyzed for PCB congeners and 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) were estimated. The highest total PCBs (40 mu g/g wet weight) found in adult cormorants from Shinobazu Pond located in Central Tokyo, was sevenfold higher than that from Lake Biwa. IUPAC 153 was the most abundant congener in adults and eggs, whereas IUPAC 28 + 31 was higher in some chicks and exhibited growth-related congeneric enrichment. The estimated metabolic index (MI) for PCB congeners revealed that mono- and non-ortho coplanars had higher bioaccumulation in cormorant liver and were expected to cause toxic effects. Among non-ortho coplanars, IUPAC 126 was predominant, and total non-ortho coplanars and TEQs in cormorants were threefold higher in Shinobazu Pond than those from Lake Biwa. The non-ortho IUPAC 126 contributed a higher portion to the total TEQs followed by IUPAC 105 and IUPAC 77. The hepatic IUPAC 169/126 ratio increased significantly with TEQs, implying a potential induction of drug-metabolizing enzymes in Shinobazu Pond cormorants. Based on the available data, PCB contamination in cormorants is enough to pose sublethal effects, especially in Shinobazu Pond and Godaiba Island, Tokyo, Japan. This could be a reason for recently observed high chick and juvenile mortality in those colonies in Tokyo.
  • MP Zakaria, A Horinouchi, S Tsutsumi, H Takada, S Tanabe, A Ismail
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 34 (7) 1189 - 1196 0013-936X 2000/04 [Peer-reviewed]
     Scientific journal 
    The Straits of Malacca is one of the world's busiest supertanker routes, and tanker-derived oil spills occur frequently. In addition, domestic oil spills have been increasing due to growing industrialization of Malaysia. The determination of the exact source of the spills is critically important. This paper examines the utility of biomarker compounds, triterpanes, to identify the source of the oil spills. Middle East crude oils (MECO), South East Asian crude oils (SEACO), tar-balls, sediments, and mussels were analyzed. The most distinctive compositional features for the crude oils are that 17 alpha 21 beta(H)C(29) norhopane and C(31)-C(35) homohopanes, especially C(35) homohopanes, are depleted in SEACO. These remarkably different hopane compositions can be explained by the fact that MECO and SEACO are derived from carbonate (marine) and lacustrine/deltaic shale (nonmarine) source rocks, respectively. Two of the eight tar-balls samples collected on the coast of Peninsular Malaysia were identified to be derived from Middle East petroleum based on their biomarker signatures. The results of oleanane analyses imply that a low concentration of oleanane does not always indicate a Middle East petroleum contribution although at high concentration oleanane can be a useful biomarker for South East Asian oil sources. Application of the source-identifier to sediment and mussel samples showed the Middle East oil signature. One possible explanation is that Middle East oil is used in formulating Malaysian lubricating oils which are the source of oil found in sediment and mussel samples. This is consistent with the analytical results for the lubricating oil used in Malaysia and the street dust samples.
  • Monirith, I, H Nakata, M Watanabe, S Takahashi, S Tanabe, TS Tana
    WATER SCIENCE AND TECHNOLOGY 42 (7-8) 241 - 252 0273-1223 2000 [Peer-reviewed]
     
    Contamination by organochlorine compounds (OCs) was examined in fish and mussels collected from Cambodia and other Asian developing countries in 1997 and 1998. DDT and its metabolites were the predominantly detected compound in both fish and mussel samples. PCBs were second highest, followed by HCHs, CHLs, and HCB. Freshwater fish contained higher concentrations of DDTs than marine fish and mussels, implying that the source of DDTs originated from inland watersheds such as the Mekong River, Basac River, Tonlesap River, and Tonlesap Great Lake. Comparison of the OC residue levels in fish and mussels from Cambodia with those in other Asian and Oceanic regions suggested that Cambodia is one of the countries least contaminated by OCs. In other words, it can be concluded that among Asian and Oceanic countries Cambodia has kept a "Clean Environment".
  • TB Minh, MS Prudente, M Watanabe, S Tanabe, H Nakata, N Miyazaki, TA Jefferson, A Subramanian
    WATER SCIENCE AND TECHNOLOGY 42 (7-8) 231 - 240 0273-1223 2000 [Peer-reviewed]
     
    To elucidate the global distribution and toxicological impacts of persistent organochlorines (OCs) on cetaceans, the present study determined the concentrations of organochlorine pesticides such as DDT and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), chlordane compounds (CHLs) and PCBs including toxic coplanar congeners in the blubber of 10 species of adult male odontoceti cetaceans collected from several locations in the North Pacific Ocean and coastal waters of Japan, Hong Kong, Philippines and India during 1985-1997. Concentrations of tris(4-chlorophenyl) methane (TCPMe) and tris(4-chlorophenyl)methanol (TCPMOH), which are among the newly identified contaminants, were also determined. Residue pattern was in the order of DDTs greater than or equal to PCBs>CHLs>HCHs>HCB>TCPMOH>TCPMe. Greater DDT concentrations were found in cetaceans from the Japan Sea, coastal waters of Hong Kong and India, indicating serious marine pollution in industrialized Asian nations and current usage of DDTs in tropical regions. In general, cetaceans inhabiting cold and temperate waters contained relatively higher concentrations of PCBs, HCHs, CHLs and HCB as compared with those from tropical regions, reflecting atmospheric transport from the tropical sources to the northern sinks. Latitudinal distribution of TCPMe and TCPMOH in cetaceans from the North Pacific Ocean and Asian coastal waters was similar to that of DDTs, suggesting the less transportable nature of TCPMe and TCPMOH in the marine environment. Penta- and hexa-chlorobiphenyls ware the predominant PCB congeners, accounting for about 70% of the total PCBs. 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) of non- and mono-ortho coplanar PCBs in the blubber of cetaceans ranged from 36 (in spinner dolphin from Philippines) to 510pg/g wet wt tin humpbacked dolphin from I-long Kong). Toxic evaluation of coplanar PCBs using TEQ concept indicates an increasing impact on cetaceans from mid-latitudes. Mono-ortho congener IUPAC 118 or non-ortho congener IUPAC 126 was estimated to have the greatest toxicity contribution. The estimated TEQ concentrations in the blubber of some cetacean species exceeded the level associated with immunosuppresion in harbour seals.
  • S Takahashi, LTH Le, H Saeki, N Nakatani, S Tanabe, N Miyazaki, Y Fujise
    WATER SCIENCE AND TECHNOLOGY 42 (7-8) 97 - 108 0273-1223 2000 [Peer-reviewed]
     
    Concentrations of butyltin compounds (BTs), including tributyltin (TBT) and its metabolites, di-(DBT) and monobutyltin (MBT), and total tin (n=organic +inorganic tin) were determined in various tissues and organs of marine mammals collected from Japanese coastal waters. Some marine mammal species from Hong Kong, India, Philippines, Black Sea and North Pacific Ocean were analyzed for comparison. Among the organs and tissues analyzed. concentrations of Sigma BTs (TBT+DBT+MBT) and Sigma Sn were the highest in the liver. Concentrations of Sigma BTs and Sigma Sn in most coastal species were higher than those in offshore species, indicating a greater input of tin compounds in coastal waters. Lower hepatic concentrations of Sigma BTs and ratio of Sigma BTs to Sigma Sn observed in pinnipeds may be attributed to higher metabolic capacity to degrade BTs and to their excretion through hair shedding. Age trends in accumulation of both Sigma BTs and Sigma Sn showed increasing concentrations in immature growth stage and stable levels in mature animals. A significant correlation was observed between the hepatic concentrations of Sigma BTs and Sigma Sn in marine mammals. These findings suggest a significant input and/or bioaccumulation of anthropogenic tin. A significant correlation was found between concentrations of Sigma BTs (as wen as Sigma Sn) in hair and liver of pinnipeds, suggesting that hair can be used as an indicator for monitoring butyltin contamination in the body of pinnipeds under non-killing condition.
  • A Sudaryanto, S Takahashi, S Tanabe, M Muchtar, H Razak
    WATER SCIENCE AND TECHNOLOGY 42 (7-8) 71 - 79 0273-1223 2000 [Peer-reviewed]
     
    The green mussel (Perna viridis) samples were collected from Indonesian coastal waters and some other Asian countries in the period of 1997-1998 to elucidate the present status of marine pollution by butyltin compounds (BTs) including mono- (MBT), di- (DBT), and tributyltin (TBT). BTs were detected in all the mussel samples from Indonesian coastal waters in the range of 3.7 to 64 ng/g wet wt as total butyltins (Sigma BTs = MBT+DBT+TBT). The highest concentrations were found in green mussels from Jakarta Bay and Surabaya coastal waters. Relatively higher concentrations of BTs were detected in the mussels from adjacent areas of high maritime activities such as marina, harbour and fishing port. This suggests pollution of BTs arising from TBT usage in antifouling paints. BTs were also detected in mussels from aquaculture areas, implying TBT usage for fisheries activity. The composition of butyltin derivatives in green mussels from Indonesian coastal waters were in the order of TBT>MBT>DBT, suggesting fresh input of TBT in the marine environment. The contamination levels of BTs in green mussels from Indonesia were comparable or lower than those from other Asian developing countries. The elevated concentrations of BTs ware found in mussels from some areas of Thailand, Philippines, India and Malaysia where residue levels of BTs were comparable to those in developed nations.
  • S Tanabe, MS Prudente, S Kan-atireklap, A Subramanian
    OCEAN & COASTAL MANAGEMENT 43 (8-9) 819 - 839 0964-5691 2000 [Peer-reviewed]
     Scientific journal 
    Contamination by butyltin (BTs) and organochlorine compounds (OCs) in green mussels collected along the coastal areas of Thailand, Philippines and India during the period of 1994-1997 was examined. The BT residues in green mussel were widely detected, suggesting a widespread contamination along the coastal waters of Asian developing countries. Relatively high concentrations of BTs in green mussel were found in high boating activity and coastal aquaculture areas, implying the usage of TBT as a biocide in antifouling paints used on boat hulls and marine aquaculture facilities. The composition of BT derivatives in mussel was in the order of TBT > DBT > MET, suggesting also the presence of significant butyltin source in Asian coast. BT residues pattern in green mussels from Thailand revealed higher levels in aquaculture than in boating activity sites. This result may indicate that the developing countries showing high economic growth rate (like Thailand) tend to increase the usage of TBT for aquaculture activities. BT contamination levels in Asian developing countries were lower than those in developed nations. However, considering the fact that the unregulated usage of organotins in Asian developing countries and the increasing demand for antifouling paints in Asia-Pacific regions, BTs contamination in aquatic environment may be serious in future. Concentrations of OCs detected in green mussels were lower than BTs. Considerable residues of p. p'-DDT found in mussel indicated the current usage of DDTs in Asian regions. HCHs and DDTs contamination in India is apparently higher than in other Asian developing countries. The present study clearly indicates that the aquatic environment in Asia-Pacific regions is still being contaminated by some OCs. To our knowledge, this is a first report on the detection of butyltin compounds in green mussels (Perna viridis) from Thailand, Philippines and India. (C) 2000 Elsevier Science Ltd. All rights reserved.
  • T. B. Minh, H. Nakata, M. Watanabe, S. Tanabe, N. Miyazaki, T. A. Jefferson, M. Prudente, A. Subramanian
    Archives of Environmental Contamination and Toxicology 39 (3) 398 - 410 0090-4341 2000 [Peer-reviewed]
     Scientific journal 
    To elucidate the global distribution and toxicological impacts of polychlorinated biphenyls (PCBs) on cetaceans, the present study determined the concentrations of individual PCB congeners, including toxic non-ortho (IU-PAC Nos. 77, 126, 169) and mono-ortho (IUPAC Nos. 105, 118, 156) coplanar congeners, in the blubber of 10 species of adult male odontocetes collected from several locations in the North Pacific Ocean and along coastal waters of Japan, Hong Kong, the Philippines, and India during 1985-1997. Total PCB concentrations in cetaceans from temperate and cold waters were higher than those in cetaceans from tropical regions. Residue levels were found to be the highest in Fraser's dolphins collected off Kii Peninsula, Japan, and hump-backed dolphins from Hong Kong, reflecting serious marine pollution by PCBs in industrialized Asian countries. Penta- and hexa-chlorobiphenyls were the predominant PCB congeners, accounting for about 70% of the total PCBs. 2,3,7,8-Tetrachlorodibenzo-p-dioxin equivalents (TEQs) of non- and mono-ortho coplanar PCBs in the blubber of cetaceans ranged from 36 (in spinner dolphins from the Philippines) to 510 pg/g wet weight (in hump-backed dolphins from Hong Kong). Toxic evaluation of coplanar PCBs using the TEQ concept indicates an greater impact on cetaceans from mid-latitudes. Toxicity contribution of mono-ortho congener IUPAC 118 was prominent in species from high latitude oceans, such as the Bering Sea and the North Pacific, whereas non-ortho congener IUPAC 126 accounted for the highest contribution in cetaceans from lower latitude regions, such as the Philippines and India. The estimated TEQ concentrations in the blubber of some cetacean species, such as northern right whale dolphin and Pacific white-sided dolphin from the northern North Pacific, Dall's porpoise from the Japan Sea, striped dolphin off Sanriku and Fraser's dolphin off Kii Peninsula, Japan, hump-backed dolphin and finless porpoise from Hong Kong, exceeded the levels associated with immunosuppression in harbour seals.
  • H. Sakai, K. Saeki, H. Ichihashi, N. Kamezaki, S. Tanabe, R. Tatsukawa
    Archives of Environmental Contamination and Toxicology 39 (3) 378 - 385 0090-4341 2000 [Peer-reviewed]
     Scientific journal 
    Concentrations of nine heavy metals (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Co, and Hg) were determined in liver, kidney, and muscle of 50 green turtles (Chelonia mydas) collected from Yaeyama Islands, Okinawa, Japan, to elucidate growth-related changes in heavy metal accumulation during different growth stage. Considerably high Cu concentrations were found in the liver of smaller turtles. Mean hepatic concentration of Cu was 50.2 μg/g wet weight which varied widely (4.27-113 μg/g wet weight). Cadmium concentrations decreased with increasing the carapace length. The juvenile green turtles in the pelagic ocean are likely feed on zooplankton, while adult coastal inhabiting green turtles mainly feed on sea grasses and sea-weeds. Concentrations of Cd in sea plants are lower than those in zooplankton. The specific accumulation of Cd found in the green turtle seems to be attributable to their feeding habit, which is a shift from carnivore to herbivore at different growth stages.
  • G. Yasunaga, I. Watanabe, M. S. Prudente, A. Subramanian, V. Qui, S. Tanabe
    Toxicological and Environmental Chemistry 77 (1-2) 75 - 92 0277-2248 2000 [Peer-reviewed]
     Scientific journal 
    Concentrations of V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Hg, Tl, and Pb were determined in the liver of 9 species of waders including migratory and resident collected from north Vietnam, south India, and the Philippines. Renal Cd concentrations were also determined. Most elements showed no significant differences between genders and among localities. Concentrations of almost all the elements in birds, except for Cr and Se in the kentish plover from Vietnam, were found to be decreased or less varied during the wintering season. Toxic element levels in waders were dependent on the migration distance. Pb levels in dunlins from Vietnam and Cd levels in pintail snipe from Philippines seemed to be in toxicologically critical on their health condition.
  • TB Minh, M Watanabe, S Tanabe, N Miyazaki, TA Jefferson, MS Prudente, A Subramanian, S Karuppiah
    ENVIRONMENTAL POLLUTION 110 (3) 459 - 468 0269-7491 2000 [Peer-reviewed]
     Scientific journal 
    For understanding global distribution, transport and behavior of tris(4-chlorophenyl)methane (TCPMe) and tris(4-chlorophenyl)methanol (TCPMOH), the two newly identified microcontaminants, the present study determined their concentrations and other persistent organochlorines (OCs) in the blubber of nine species of adult male cetaceans collected from various locations in the North Pacific Ocean and coastal waters of some Asian countries, during 1985-97. Concentrations of TCPMe and TCPMOH were found to be highest in northern right whale dolphins, which may be attributable to wide distribution of this species, including some heavily polluted areas such as coastal California. Elevated residue levels of TCPMe and TCPMOH were observed in both off-shore and coastal species, suggesting widespread contamination of these compounds in the marine environment, Higher contamination of TCPMe and TCPMOH was found in cetaceans from temperate and cold waters than those from tropical regions. The latitudinal distribution of TCPMe and TCPMOH in cetaceans from the North Pacific and Asian coastal waters was similar to that of DDTs, suggesting less transportable nature of TCPMe and TCPMOH in the marine environment. Data on the occurrence of TCPMe and TCPMOH further indicated high bioaccumulation potential of these compounds, which was comparable to DDTs. Relative concentrations of TCPMe/TCPMOH in cetaceans were apparently higher than those observed in seals, suggestive of lower metabolic capacity for these compounds in cetaceans than in pinnipeds, which is similar to classic contaminants like polychlorinated biphenyls and DDTs. (C) 2000 Elsevier Science Ltd. All rights reserved.
  • 高橋 厚・Le, L. T. H, 田辺信介
    環境科学会誌 13 (3) 397 - 404 2000 [Peer-reviewed]
  • K Saeki, Y Okabe, EY Kim, S Tanabe, M Fukuda, R Tatsukawa
    ENVIRONMENTAL POLLUTION 108 (2) 249 - 255 0269-7491 2000 [Peer-reviewed]
     Scientific journal 
    Mercury (Hg) and cadmium (Cd) in common cormorants (Phalacrocorox carbo) collected in Lake Biwa, Japan and Tokyo, Japan, were investigated to elucidate the biological behaviors of these elements, and to assess exposure to these pollutants of wild, fish-eating birds. Hg and Cd concentrations were highest in the liver and kidneys, respectively. The lowest levels of both elements were observed in chicks. Hg concentrations in all tissues except brain increased significantly with growth from chicks to juveniles (p < 0.05, U-test). Cd concentrations in the kidneys and liver also increased significantly during growth from juvenile to adult (p < 0.005, U-test). When comparing hepatic Hg and Cd in adult birds between 10 samples from Lake Biwa and nine samples from Tokyo, the Cd concentrations in the Lake Biwa samples (1.4 +/- 0.37 mu g/g dry wt) (mean +/- SD) were significantly higher than those from Tokyo (0.32 +/- 0.16 mu g/g dry wt) (p < 0.005, U-test), while no statistically significant difference was found in the Kg concentrations. Possible causes of these differences were discussed in relation to their prey. (C) 2000 Elsevier Science Ltd. All rights reserved.
  • 安永玄太, 田辺信介, 金 恩英, 岩田久人, 須藤明子, 増田 泰, 藤田正一, 神 和夫
    環境科学会誌 13 (1) 51 - 59 2000 [Peer-reviewed]
  • M Watanabe, S Tanabe, R Tatsukawa, M Amano, N Miyazaki, EA Petrov, SL Khuraskin
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 37 (3) 396 - 407 0090-4341 1999/10 [Peer-reviewed]
     Scientific journal 
    Persistent organochlorines, such as polychlorinated biphenyls (PCBs) including coplanar congeners, DDTs, HCHs, chlordanes (CHLs), and HCB, were determined in the blubber of Caspian seals (Phoca caspica) and their fish diet (Rutilus sp.) collected in 1993 from the northern Caspian Sea, Russia. Notable concentrations of DDTs and HCHs were found at mean values of 19 and 1.3 mu g/g on wet-weight basis in adult male seals, respectively. PCB pollution in Caspian seals was not so considerable compared with those of seals that suffered mass mortality. Less gender difference of organochlorine residue levels in adult animals implies less excretion of organochlorines from the body of adult females through lactation and gestation, probably due to the higher rate of pregnancy failure. Immature seals had a wide range of organochlorine concentrations, which decreased as body length increased, suggesting dilution. Caspian seals can be considered to have higher degradation capacity for coplanar PCBs. Mean TEQs (2,3,7,8-TCDD toxic equivalents) for non-, mono- and di-ortho coplanar PCBs was 51 pg/g on wet-weight basis, which was lower than those in seals that have suffered mass mortality, but comparable to those found in Arctic seals.
  • Monirith, I, H Nakata, S Tanabe, TS Tana
    MARINE POLLUTION BULLETIN 38 (7) 604 - 612 0025-326X 1999/07 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorines (OCs) such as PCBs (polychlorinated biphenyls), DDT compounds (DDTs), HCH (hexachlorocyclohexanes) isomers (HCHs), chlordane compounds (CHLs) and HCB (hexachlorobenzene) were determined in 27 species of marine and freshwater fish collected from Cambodia. DDT and its derivatives mere the predominantly detected compounds in both marine and freshwater fish. PCBs were the second highest followed by HCHs, CHLs and HCB. Freshwater fish contained higher concentrations of DDTs than those of marine fish, implying that the sources of DDTs originate from inland watersheds such as the Mekong River, Basac River, Tonlesap River and Tonlesap Great Lake. Comparison of the OCs residue levels in Cambodian fish with those in other Asian and Oceanic regions suggested that Cambodia is one of the less-contaminated countries by OCs. In other words, it can be concluded that Cambodia has kept "Clean Environment" among Asian and Oceanic countries. (C) 1999 Elsevier Science Ltd. All rights reserved.
  • S Takahashi, S Tanabe, Takeuchi, I, N Miyazaki
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 37 (1) 50 - 61 0090-4341 1999/07 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (BTs), including tributyltin (TBT) and its breakdown products, di- (DBT) and monobutyltin (MBT), were determined in sea water, sediment, and biota at various trophic levels in the food chain collected from Otsuchi Bay, Japan, for understanding distribution and bioaccumulation of BTs in natural marine ecosystems. BT residues were detected in all the compartments analyzed, although their concentrations appeared to be less than those in polluted areas. Concentrations of BTs in sea water were higher in locations near Otsuchi Port, indicating that maritime activities in the harbor has been a major source of BTs in this bay. A specific peak in BT residue levels was found in sediment cores at an estimated depth that dated to be from the 1980s. Lack of significant variation in the composition of BTs at different depths of cores suggests slow degradation rate of these compounds in sediments. BTs were accumulated in plankton and other organisms up to similar to 70,000 times higher than in sea water. However, no considerable biomagnification was observed for BTs through the food chain. Relatively high concentrations were found in caprellids and smaller fish, such as gunnels. These organisms accumulated TBT as the predominant compound among BT derivatives and showed higher bioconcentration factors for TBT than in other species reported so far. Our results suggest that certain organisms in the food chain may have a less capacity to degrade TBT, and therefore may accumulate BTs at elevated levels.
  • K Senthilkumar, K Kannan, RK Sinha, S Tanabe, JP Giesy
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 18 (7) 1511 - 1520 0730-7268 1999/07 [Peer-reviewed]
     Scientific journal 
    Isomer-specific concentrations of polychlorinated biphenyls (PCBs) including non-, mono-, and di-ortho-substituted congeners, DDT and its metabolites, hexachlorocyclohexane (HCH) isomers, chlordane compounds, and hexachlorobenzene (HCB) were determined in river dolphin blubber and prey fishes collected during 1993 through 1996 from the River Ganges in India. Concentrations of organochlorines were also measured in the milk and liver of dolphins, benthic invertebrates, and sediments. The DDTs and PCBs were the predominant compounds found in dolphin tissues and fish that comprise the diet of dolphins. Concentrations of DDTs and PCBs in the blubber of dolphins were in the range of 30 to 120 and 15 to 25 mu g/g, lipid weight, respectively. Penta- and hexachlorobiphenyls collectively accounted for 68 to 80% of the total PCB concentrations in river dolphins. Hexachlorobiphenyl congener 138 (2,2',3,4,4',5'-) was the most abundant in dolphin blubber and prey fishes. The isomer/congener pattern of PCBs and organochlorine pesticides suggested that there is less metabolism due to cytochrome P450 enzymes in Ganges river dolphins than in marine or terrestrial mammals. The mean 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) estimated in river dolphin blubber was greater than those that can cause adverse effects in mink. Comparison of organochlorine concentrations in river dolphins with those of the values reported for samples analyzed during 1988 through 1992 suggested that the contamination by these compounds has increased in the River Ganges.
  • LTH Le, S Takahashi, K Saeki, N Nakatani, S Tanabe, N Miyazaki, Y Fujise
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 33 (11) 1781 - 1786 0013-936X 1999/06 [Peer-reviewed]
     Scientific journal 
    There have been few reports on quantitative discussion of organic tin compounds based on total tin in environmental media and biota. The present study determined concentrations of total tin (Sigma Sn = organic + inorganic) and butyltin compounds (Sigma BTs = MBT + DBT + TBT) in the livers of cetaceans collected from Japanese coastal waters in order to estimate the ratio of Sigma BTs:Sigma Sn and to elucidate the role of anthropogenic butyltins in the view of total tin accumulation in these higher trophic organisms. Additionally, some cetacean species from open seas and oceans were also subjected to analyses for comparison purposes. Higher concentrations of Sigma Sn and Sigma BTs were found in coastal species than in offshore species, indicating greater input of tin compounds in coastal waters surrounding Japan. Sigma Sn concentrations increased with an increase in Sigma BTs residues in all species analyzed (r = 0.95, p < 0.001). Furthermore, Sigma BTs made up considerably higher percentages of the hepatic Sigma Sn in coastal species, with up to 74% in finless porpoise (Neophocaena phocaenoides) and 90% in bottlenose dolphin (Tursiops troncatus). These findings suggest that hepatic tin in coastal cetaceans predominantly exists in organic form such as butyltin compounds, implying that tin residues in marine mammals reflect mostly the input from anthropogenic sources. Despite some similar features expected between the residues of tin and mercury, anthropogenic exposure to tin compounds seems to be more apparent than exposure to mercury, which generally originates from natural exposure.
  • M Prudente, H Ichihashi, S Kan-Atireklap, Watanabe, I, S Tanabe
    FISHERIES SCIENCE 65 (3) 441 - 447 0919-9268 1999/04 [Peer-reviewed]
     Scientific journal 
    Contamination by butyltins (BTs), organochlorine compounds (OCs) and heavy metals was examined in green mussels collected along the coastal areas of the Philippines in 1994 and 1997. Significant BTs concentrations revealed widespread contamination along nearshore marine waters. Relatively high BTs concentrations were observed in samples collected from areas with high boating activities, suggestive that the source of TBT (tributyltin) is coming from antifouling paints. While TBT levels were found to be low in green mussels collected from aquaculture areas, implying minimal usage of BTs for aquaculture activities. The composition of BT derivatives in mussel was in the order of TBT > DBT > MET, reflective of continuous input of TBT in the coastal waters. Considering the unregulated use of organotins in the country, BTs contamination in the aquatic environment of the Philippines may increase in the future. Concentrations of OCs in green mussels were less than BTs. Among OCs, PCBs concentrations were found to be relatively high particularly in mussels from Manila Bay. Moreover, metal concentrations found suggest that the anthropogenic loading of Hg, Pb and Cd to the coasts is relatively low, suggestive that the green mussels from these coastal waters are not adversely affected by these metal toxicants and pose no risk for human health. To our knowledge, this is the first comprehensive report on the concentrations of butyltins, organochlorine compounds and heavy metals in soft tissues of green mussels in the Philippines.
  • EY Kim, R Goto, H Iwata, Y Masuda, S Tanabe, S Fujita
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 18 (3) 448 - 451 0730-7268 1999/03 [Peer-reviewed]
     Scientific journal 
    Concentrations of lead, mercury, and cadmium in the liver, kidney, and muscle of four Steller's sea eagles (Haliaeetus pelagicus) and one white-tailed sea eagle (Haliaeetus albicilla) that were found dead or debilitated and subsequently died in Hokkaido, Japan, from 1986 to 1997 were determined. High lead concentrations (>70 mu g/g dry weight) were detected in the liver of two Steller's sea eagles and the white-tailed sea eagle. Lead shot was also found in the intestine and gizzard of one Steller's sea eagle and the white-tailed sea eagle, respectively. Mercury and cadmium concentrations in the tissues of these raptors were low, implying that the toxicities of these elements were negligible. These results indicate that eagles in Hokkaido are suffering from secondary poisoning through ingestion of lead shot embedded in the tissue of their prey.
  • M Watanabe, S Tanabe, N Miyazaki, EA Petrov, WM Jarman
    MARINE POLLUTION BULLETIN 39 (1-12) 393 - 398 0025-326X 1999/01 [Peer-reviewed]
     Scientific journal 
    Pour seal species (Phoca caspica, Phoca sibirica, Phoca hispida and Phoca largha) and one whale (Orcinus orca) from Russia and Japan were examined to determine the body distribution, bioaccumulation and contamination status of tr is(4-chlorophenyl) methane (TCPMe) and tris(4-chlorophenyl) methanol (TCPMOH), Lipid normalized concentrations of TCPMe and TCPMOH were comparable in various organs and tissues, implying that their body distribution is followed to the lipid-dependent accumulation, similar to that for other organochlorines, The highest body burden of these compounds was found in the blubber. Bioaccumulation potential of TCPMe and TCPMOH was high and comparable to PCBs and DDTs, Relatively higher concentrations of TCPMe and TCPMOH were observed in Caspian seal than in other seal species examined. TCPMOH concentration in killer whale was the highest of the marine mammals examined. Another peak detected had similar mass spectrum to TCPMOH, however, at a different retention time, suggesting the presence of an isomer of TCPMOH, (C) 1999 Elsevier Science Ltd. All rights reserved.
  • TB Minh, M Watanabe, H Nakata, S Tanabe, TA Jefferson
    MARINE POLLUTION BULLETIN 39 (1-12) 383 - 392 0025-326X 1999/01 [Peer-reviewed]
     Scientific journal 
    Blubber samples of 2 cetacean species, the Indo-Pacific hump-backed dolphin (Sousa chinensis) (n = 11) and finless porpoise (Neophocaena phocaenoides) (n = 9), collected from Hong Kong coastal waters were analysed for persistent organochlorines. Mean concentration in the blubber of DDTs was ranked first (46 mu g/g wet wt.), followed by PCBs (24 mu g/g wet wt.), HCHs (0.76 mu g/g wet wt.), chlordane compounds (0.38 mu g/g wet wt.) and HCB (0.07 mu g/g wet wt.). The present cetacean species may potentially be faced with high risk due to the elevated level of DDTs and PCBs, Relatively high concentrations of PCBs and DDTs can be attributed to the continuous environmental input of these compounds in the Far East region including Hong Kong, Highly chlorinated PCBs such as IUPAC Nos. 138, 153, 180 were the prominent congeners, accounting for 39% of the total PCBs, Mean concentrations of 6 non- and mono-ol tho coplanar congeners were 2.1 and 2.8 mu g/g wet wt. in the hump-backed dolphin and finless porpoise, respectively. Among highly toxic coplanar PCBs, mono-ortho congener IUPAC No. 118 and non-ortho congener IUPAC No. 126 were estimated to have the greatest toxicity contribution. Tris(4-chlorophenyl) methane (TCPMe) and tr is(4-chlorophenyl) methanol (TCPMeOH), which have been the most recently identified microcontaminants, were also detected with the highest concentration of 290 and 300 ng/g (wet wt, basis), respectively, The concentrations of TCPMe relative to TCPMeOH in cetaceans from Hong Kong coastal waters were significantly higher than those found in various seals collected from other parts of the world, suggesting the different metabolic system of these two compounds between seals and cetaceans, Correlations between the concentrations of tr is-chlorophenyl compounds with other persistent organochlorines such as HCHs, CHLs, DDTs and PCBs were significant, suggesting their accumulation nature similar to these organochlorines. (C) 1999 Elsevier Science Ltd. All rights reserved.
  • Kurunthachalam Senthilkumar, Mafumi Watanabe, Kurunthachalam Kannan, Annamalai Subramanian, Shinsuke Tanabe
    Toxicological and Environmental Chemistry 71 (1-2) 221 - 239 0277-2248 1999 [Peer-reviewed]
     Scientific journal 
    Isomer-specific concentrations of polychlorinated biphenyls (PCBs) including highly toxic non-, mono- and di-ortho coplanar congeners were determined in resident, migratory birds and bat collected from south India. Among 11 different species, total PCB concentrations were in the range of 80-2000 ng/g (wet wt) in birds and 190-330 ng/g (wet wt) in bat. IUPAC 105, 118, 126, 138, 153 and 180 were the predominant congeners in birds and bat. Concentrations of three nonortho coplanar PCBs such as 3,3', 4,4'-T4CB, 3,3', 4,4', 5-P5CB, and 3,3', 4,4', 5,5'-H6CB were 2-3 orders of magnitude less than those of total PCBs. Toxic equivalencies (TEQs) were estimated based on Toxic Equivalent Factors (TEFs) proposed by Ahlborg et al. (Chemosphere, 28, 10491067, 1994). TEQs of non- and mono-ortho PCB congeners in various birds were in the range of 10-50 pg/g (wet wt), in which Short-billed Mongolian Plover contained the lowest and White-cheeked Tern had the highest. In most of the species, non-ortho congeners contributed greater TEQs. Toxic assessment results revealed that the TEQs in resident birds, bat and wintering migrant birds collected from India were belonging to the LOEL and NOEL levels.
  • 佐伯和利, 江崎恭志, 田辺信介, 鹿島勇治, 土井睦雄
    環境科学会誌 12 (3) 345 - 350 1999 [Peer-reviewed]
  • 上野大介, 高橋 真, 田辺信介, 池田久美子, 小山次朗
    環境化学 9 (2) 369 - 378 1999 [Peer-reviewed]
  • S Takahashi, H Mukai, S Tanabe, K Sakayama, T Miyazaki, H Masuno
    ENVIRONMENTAL POLLUTION 106 (2) 213 - 218 0269-7491 1999 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (BTs) including mono-(MBT), di-(DBT) and tributyltin (TBT) were determined in livers of humans and wild terrestrial mammals, such as raccoon dogs (Nyctereutes procyonoids) and monkeys (Macaca fuscata) from Japan. In addition, 22 samples of plastic products were analyzed. BT residues were detected in all the liver samples of humans and raccoon dogs, with concentrations of < 360 ng/g wet wt, whereas concentrations in the liver of monkeys were either less than the detection limit or were only in trace levels. Elevated concentrations of BTs, particularly DBT (< 140,000 ng/g) and MBT (< 130,000 ng/g), were found in some plastic products, such as baking parchments made from siliconized paper and gloves made up from polyurethane. The results of a cooking test using the above baking parchment indicated the transfer of BTs to foodstuffs. These observations suggest expansion of BT contamination among terrestrial mammals. BT pollution from industrial appliances, such as plastic stabilizers and catalysts other than those of marine origin as antifouling agents, are suggested as alternative sources of exposure. (C) 1999 Elsevier Science Ltd. All rights reserved.
  • GB Kim, KA Maruya, RF Lee, JH Lee, CH Koh, S Tanabe
    MARINE POLLUTION BULLETIN 38 (1) 7 - 15 0025-326X 1999/01 [Peer-reviewed]
     Scientific journal 
    Sixty-six sediment samples were collected from Kyeonggi Bay, Korea, in December 1995 and analysed for a suite of 2-6 ring polycyclic aromatic hydrocarbons (PAHs). Sediments were collected in the Han River estuary, Incheon Harbour, from nearshore locations adjacent to large industrial complexes south of Incheon, and along transects toward the open sea. Concentrations of PAHs (9.1-1400 ng g(-1) dry wt with an average of 120 ng g(-1)) were positively correlated with organic carbon (OC) content and negatively correlated with mean sediment grain size. The highest PAH concentrations were in samples from inner Incheon Harbour basins; these levels decreased within a short distance from these heavily industrialised waterways. The sources of PAHs were determined to be primarily combustion in nature based on the distribution of alkylated homologs to parent compounds. Overall, sediment PAHs in Kyeonggi Bay were lower than those in the United States and Europe. The potential For biological effects due to PAHs alone is expected to be low based on comparisons of individual and Sigma PAH concentrations with effects-based and equilibrium partitioning-based sediment quality guidelines/criteria. (C) 1999 Elsevier Science Ltd. All rights reserved.
  • Kurunthachalam Senthilkumar, Shinsuke Tanabe, Kurunthachalam Kannan, Annamalai Subramanian
    Toxicological and Environmental Chemistry 68 (1-2) 91 - 104 0277-2248 1999 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (BTs) such as mono- (MBT), di- (DBT) and tributyltin (TBT) were determined in soft tissue homogenates and feathers of resident and migratory birds collected from South India. Concentrations of ΣBTs (sum of TBT + DBT + MBT) in soft tissue body homogenates were comparable between residents (< 8.0 - < 27 ng/g) and migrants (< 8.0-28 ng/g). On the other hand, concentrations in feathers were much greater than in soft tissue body homogenates and were also comparable between residents (14-190ng/g) and migrants (< 9.9 - 300 ng/g). The total BT burden in consolidated feathers was about 36%. The sex differences in concentrations and burdens of BTs were less pronounced in birds. Among BT compounds examined, MBT occupied a major proportion, followed by DBT and TBT in most resident and migratory birds. Comparison of BT concentrations with birds from other parts of the world revealed that the Indian birds were less contaminated. To our knowledge, this is a first report on the detection of BTs in birds collected from developing countries.
  • EY Kim, R Goto, S Tanabe, H Tanaka, R Tatsukawa
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 35 (4) 638 - 645 0090-4341 1998/11 [Peer-reviewed]
     Scientific journal 
    The concentrations of 14 trace elements (Li, V, Mn, Co, Cu, Zn, Se, Rb, Sr, Ag, Cd, Cs, Pb, and Hg) were determined in tissues and organs of three species and in the liver of 11 species of seabirds. Comparatively high concentrations of Li, Co, Sr, and V were found in the femur. Cd, Se, Cu, and Mn concentrations were relatively higher in the kidney than in other tissues and organs. Rb, Cs, and Pb concentrations were rather uniform among tissues. Concentrations of essential elements such as Mn, Cu, and Co were comparable among seabird species, except high Cu concentrations in northern giant petrel. Among nonessential elements, concentrations of Cd and Hg were variable according to seabird species. Pb levels were low in all the species. High Se levels (100 mu g/g dry weight) were found in the Liver of black-footed albatross and grey petrel. There were significant positive correlations between Se and Cd concentrations in three species and between Se and Hg in black-footed albatross, suggesting that Se has an antagonistic action on the toxic effects of Cd and Hg. Concentrations of Li, V, Ag, and Cs were usually low (less than 1 mu g/g dry weight).
  • Watanabe, I, S Tanabe, M Amano, N Miyazaki, EA Petrov, R Tatsukawa
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 35 (3) 518 - 526 0090-4341 1998/10 [Peer-reviewed]
     Scientific journal 
    Concentrations of Fe, Mn, Zn, Cu, Cd, and Hg were determined in the liver, kidney, and muscle of 60 Baikal seals collected from Lake Baikal in 1992 to investigate age-dependent accumulation. Among essential elements, Fe concentrations in the muscle, liver, and kidney increased with age, suggesting development of diving ability. The concentrations of Mn, Zn, and Cu decreased with age, especially at immature stages. Toxic elements such as Hg and Cd decreased in adult males and thus the male-female difference was clearly observed in their concentrations, which differed from patterns usually found in marine mammals. Such accumulation patterns were due to difference in the feeding rates between males and females under low exposure to Hg and Cd. In addition, a greater excretion of Hg than that of Cd through molting and parturition was estimated.
  • K Senthilkumar, K Kannan, S Tanabe, M Prudente
    FRESENIUS ENVIRONMENTAL BULLETIN 7 (9-10) 561 - 571 1018-4619 1998/09 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (BTs), such as mono- (MBT), di- (DBT) and tributyltin (TBT), were determined in different body tissues and feathers of migratory (Long-billed Mongolian Plover, MP) and resident (Chinese-little Bittern, CLB) birds collected from Philippines. Concentrations of BTs in soft tissues were 6.1 - 23 ng/g (wet wt) in MP and 6.3 -3 2 ng/g in CLB. Butyltin concentration was high in mixed tissue, muscle and bones. Highest concentrations of BTs were found in feathers (12 - 290 ng/g). Noticeably, tail feathers recorded elevated concentrations with a range of 73 - 360, 29 - 56 and 37 - 67 ng/g; for MET, DBT and TBT, respectively. Composition of MBT was found higher followed by DBT and TBT in all the tissues and feathers. Comparision of BT composition in birds from several countries suggested that the birds from Philippines had greater concentrations than those from India, but less than those from developed nations.
  • H Nakata, S Tanabe, R Tatsukawa, Y Koyama, N Miyazaki, S Belikov, A Boltunov
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 17 (9) 1745 - 1755 0730-7268 1998/09 [Peer-reviewed]
     Scientific journal 
    Ringed seals collected from the Kara Sea in the Russian Arctic during 1995 were analyzed for persistent organochlorines (OCs) such as DDTs, polychlorinated biphenyls (PCBs), chlordane compounds (CHLs), hexachlorocyclohexanes (HCHs), and hexachlorobenzene to understand the present status of contamination. Noticeably higher levels of DDTs and PCBs were detected in ringed seals from the Russian Arctic when the values compared with same species from the Canadian Arctic and the Norwegian Arctic. This suggests the presence of significant local sources of DDTs end PCBs in Russia or nearby areas. Concentrations of CHLs and HCHs in ringed seals were comparable with those in this species elsewhere in circumpolar regions, probably as a consequence of uniform distribution of CHLs and HCHs due to the atmospheric transport of these compounds to the Arctic region. Larga seals collected from the Sea of Okhotsk were also analyzed for OCs to compare residue levels and accumulation patterns with those in ringed seals. In larga seals, the prominent residues were DDTs end PCBs, with levels comparable or slightly lower than those in ringed seals. Lactational transfer of PCBs, DDTs, and CHLs was evident in ringed seals based on increasing concentrations with age in males but not in females. The transfer rates were estimated to be 38% for DDTs, 25% for PCBs, and 30% for CHLs of the whole body burden in the mature female. Comparison of the PCB congener pattern accumulated in seals suggested that ringed seals have an greater capacity to degrade toxic non-ortho (IUPAC 126) and mono-ortho (IUPAC 105 and 118) coplanar congeners than did Baikal seals, but a lower capacity than found in larga seals.
  • H Iwata, S Tanabe, T Iida, N Baba, JP Ludwig, R Tatsukawa
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 32 (15) 2244 - 2249 0013-936X 1998/08 [Peer-reviewed]
     Scientific journal 
    Tissues of northern fur seals (Callorhinus ursinus) from the Pacific coast of Japan and double-crested cormorants (Phalacrocorax auritus) from the Great Lakes were analyzed in order to explore the enantioselective accumulation of alpha-hexachlorocyclohexane (HCH). The effects of biological and ecological factors such as species, tissue, sex, age, feeding habit, and habitat, which may be attributable to the differences in accumulation between enantiomers, were also investigated. The enantiomeric ratios (ERs) of (+)-/(-)-alpha-HCH in fat tissue of female fur seals, composed of different age groups, collected in 1986 (1.58 +/- 0.25) exhibited greater values than those in abiotic and lower trophic levels previously reported. No age trend of ERs was found in female northern fur seals. There appeared to be a temporal transition of ERs in adult female northern fur seals collected in 1971-1988. Regression analysis showed a significant relationship between ERs and feeding habits (p = 0.003). Analysis of breast muscle of double-crested cormorants exhibited no sex difference in ERs. ERs (1.26 +/- 0.13) in cormorants from Lake Michigan were significantly higher than those (1.01 +/- 0.18) from Lake Superior (p = 0.002), suggesting the effects of factors such as feeding habit and habitat. Enantiomeric accumulation in the body of double-crested cormorants was tissue-specific. No age trend of ERs was seen in breast muscle of cormorants. The result implies that sexual maturity, aging and breeding activities are less effective for changing ERs. The ERs in higher trophic animals could be influenced by species-specific metabolism and transport process in the body as biological factors and by feeding habit and habitat as ecological factors.
  • S Takahashi, JS Lee, S Tanabe, T Kubodera
    SCIENCE OF THE TOTAL ENVIRONMENT 214 (1-3) 49 - 64 0048-9697 1998/06 [Peer-reviewed]
     Scientific journal 
    Organochlorine (OC) and butyltin (BT) residues were detected in deep-sea and shallow water organisms collected from Suruga Bay, Japan. Among OCs, residue levels of polychlorinated biphenyls (PCBs) were highest in deep-sea organisms with up to 2800 ng/g lipid wt. Total butyltin (CBT) concentrations in deep-sea organisms were found to be 980 ng/g wet wt. at maximum levels. Residue levels of OCs in both deep-sea and shallow water organisms from Suruga Bay were lower than those in industrialized areas like Tokyo Bay, whereas residue levels of BTs were comparable or higher. These facts clearly indicate the expansion of BT pollution in deep-sea ecosystems. The deep-sea organisms showed no consistent trend between OC concentrations and prey-predator relationships, while the accumulative pattern of BTs appeared to be influenced by food-chain magnification and feeding habits of the organisms. OC compositions in deep-sea organisms showed a higher ratio of p,p'-DDE, trans-nonachlor and beta-HCH among their related compounds and isomers. Whereas TBT (tributyltin) as a parent compound of BT was predominant in deep-sea organisms, suggesting a fresh input of TBT into the deep-sea environment. (C) 1998 Elsevier Science B.V.
  • H Hoshi, N Minamoto, H Iwata, K Shiraki, R Tatsukawa, S Tanabe, S Fujita, K Hirai, T Kinjo
    CHEMOSPHERE 36 (15) 3211 - 3221 0045-6535 1998/06 [Peer-reviewed]
     Scientific journal 
    In order to understand the residue levels of organochlorine compounds (OCs) and their accumulation patterns in wildlife inhabiting Chubu region, Japan, the concentrations of polychlorinated biphenyls (PCBs), hexachlorocyclohexane isomers (HCHs), DDT compounds (DDTs) and hexachlorobenzene (HCB) were measured in 8 species of terrestrial mammals and 10 species of birds. In view of feeding habits, the contamination levels of OCs were found to be higher in omnivorous mammals than in herbivorous ones, and in fish-eating ones and raptores than in omnivorous birds. In fox and dog, PCB 180 (2, 2', 3, 4, 4', 5, 5'-heptachlorobiphenyl) was the most dominant PCB congener, while in the other species PCB-153 (2, 2', 3, 4', 5, 5'-hexachlorobiphenyl) was the most persistent. The ratios of lower chlorinated PCB congeners (tri- to tetra-) to total PCBs were larger in fish-eating birds than in the other birds. The results indicate that the compositions of PCB congeners would reflect the differences of feeding habits and xenobiotic metabolizing systems among each species. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • K Kannan, H Nakata, R Stafford, GR Masson, S Tanabe, JP Giesy
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 32 (9) 1214 - 1221 0013-936X 1998/05 [Peer-reviewed]
     Scientific journal 
    Aroclor 1268, a highly chlorinated technical PCB mixture composed of primarily hexa-through decachlorobiphenyls, was used to lubricate high voltage process equipment at a chlor-alkali facility in coastal southeastern Georgia. Disposal of process wastes has resulted in extensive contamination of environmental media at the nearby intertidal marsh. In this study, congener distribution, bioaccumulation properties, and toxic potential of superhydrophobic PCBs were examined in blue crab, fish,terrapin, and birds collected at this site. Lipid-normalized mean concentrations of total PCBs in blue crab, striped mullet, yellowtail, sea trout, diamondback terrapin, red-winged blackbird, boat-tailed grackle, mottled duck, and clapper rail were 197, 283, 203, 56, 14, 385, 76, 135, and 10 mu g/g, respectively. Hepta-, octa-, and nonachlorobiphenyls collectively accounted for 85-93% of the total PCB concentrations. The PCB congener profile in biota resembled that of Aroclor 1268, although the relative proportions of nona- and decachlorobiphenyls were less. Bioaccumulation of superhydrophobic congeners in biota, including terrapins and birds, was less than would be predicted from K-ow, which supports the hypothesis that these compounds have restricted membrane permeability. Superhydrophobic PCB congeners were less efficiently transferred in the food web. The concentrations of non-ortho coplanar congeners in blue crab were 7-8 orders of magnitude less than the total PCB concentrations. Despite notable concentrations of total PCBs, the 2,3,7,8-TCDD toxic equivalents (TEQs) estimated for non-and mono-ortho-PCBs in biota were minimal. The toxic effects of higher chlorinated PCBs, including di-ortho-substituted PCBs, need further investigation.
  • K Kannan, KS Guruge, NJ Thomas, S Tanabe, JP Giesy
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 32 (9) 1169 - 1175 0013-936X 1998/05 [Peer-reviewed]
     Scientific journal 
    Tributyltin (TBT) and its degradation products, mono-(MBT) and dibutyltin(DBT), were determined in river, kidney, and brain tissues of adult southern sea otters (Enhydra lutris nereis) found dead along the coast of California during 1992-1996. Hepatic concentrations of butyltin compounds (BTs = MBT + DBT + TBT) ranged from 40 to 9200 ng/g wet wt,which Varied depending on the sampling location and gender. Concentrations of BTs in sea otters were comparable to those reported in stranded bottlenose dolphins from the U.S. Atlantic Coast during 1989-1994. Greater accumulation of butyltins in sea otters was explained by their bottom-feeding habit and the diet that consists exclusively of invertebrates such as mollusks and gastropods. Livers of female sea otters contained approximately 2-fold greater concentrations of BTs than did those of males. The composition of butyltin compounds in sea otter tissues was predominated by TBT in most cases and suggestive of recent exposure. large harbors such as Monterey Harbor that handle ships legally painted with TBT-containing antifouling paints continued to experience ecotoxicologically significant butyltin contamination. Sea otters,which were affected by infectious diseases, contained greater concentrations of BTs in their tissues than those that died from trauma and other unknown causes.
  • S Tanabe, K Senthilkumar, K Kannan, AN Subramanian
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 34 (4) 387 - 397 0090-4341 1998/05 [Peer-reviewed]
     Scientific journal 
    Persistent organochlorines such as DDT and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were determined in whole-body homogenates of resident and migratory birds collected from South India. Organochlorine contamination pattern in birds varied depending on their migratory behaviour. Resident birds contained relatively greater concentrations of HCHs (14-8,800 ng/g wet wt) than DDTs and PCBs concentrations. In contrast, migrants exhibited elevated concentrations of PCBs (20-4,400 ng/g wet wt). The sex differences in concentrations and burdens of organochlorines in birds were pronounced, with females containing lower levels than males. Inland piscivores and scavengers accumulated greater concentrations of HCHs and DDTs while coastal piscivores contained comparable or greater amounts of PCBs. Global comparison of organochlorine concentrations indicated that resident birds in India had the highest residues of HCHs and moderate to high residues of DDTs. It is, therefore, proposed that migratory birds wintering in India acquire considerable amounts of HCHs and DDTs. Estimates of hazards associated with organochlorine levels in resident and migratory birds in India suggested that Pond Heron, Little Ringed Plover, and Terek Sandpiper may be at risk from exposure to DDTs.
  • K Saeki, N Nakatani, TH Le Le, S Tanabe
    BUNSEKI KAGAKU 47 (2) 135 - 139 0525-1931 1998/02 [Peer-reviewed]
     Scientific journal 
    The determination of the total tin in biological materials was studied using a calibration method involving ICP-MS. Prior to an ICP-MS determination, samples were subjected to microwave-digestion with HNO3. The detected intensities for all tin isotopes increased along with an increase in the HCl concentration, while the intensities did not vary with the HNO3 concentration. The addition of HNO3 acted to control the interference by 0.02 M of HCl. The total tin concentrations in biological reference materials (NIES No.11, No.6, and No. 5) were examined by the present method, and agreed well with the reported reference values. In the case of preparing 100 mg of dry samples, and obtaining a final extract volume of 10 mi, the detection limit was 10 ng Sn/g-d.w. in the present study. Considering all of these results, it can be concluded that the present method is applicable with high accuracy and sensitivity for determining the total tin in biological samples.
  • S. Kan-Atireklap, N. T.H. Yen, S. Tanabe, A. N. Subramanian
    Toxicological and Environmental Chemistry 67 (3-4) 409 - 424 0277-2248 1998 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds (BTs) and organochlorine residues (OCs) were determined in green mussel (Perna viridis L.) collected along the coastal waters of India in 1994 and 1995 to elucidate their contamination levels and distribution. BTs were detected in all of the mussel samples, ranging from 2 to 378 ng/g wet wt, which indicated that BTs are widely distributed, with elevated concentrations in intense boating areas. BTs concentrations in green mussels were lower than those reported for developed nations as well as developing countries such as Thailand. Concentrations of OCs were much lower than those of BTs. Among OCs examined, DDTs were found to be greatest, followed by HCHs, PCBs, CHLs and HCB. Considering the fact that the usage of tributyltin (TBT), DDTs and HCHs are not controlled in India, their contamination in the aquatic environment may increase unless regulatory measures are imposed. To our knowledge, this is a first report on the detection of BTs in Indian mussels.
  • Butyltins in surface sediments of Kyeonggi Bay, Koria.
    Kim, G. B, Tanabe, S, Koh, C. H
    Journal of the Korean Society of Oceanography 33 (3) 64 - 70 1998 [Peer-reviewed]
  • H Nakata, K Kannan, L Jing, N Thomas, S Tanabe, JP Giesy
    ENVIRONMENTAL POLLUTION 103 (1) 45 - 53 0269-7491 1998 [Peer-reviewed]
     Scientific journal 
    Concentrations of PCBs, DDTs (p,p'-DDE, p,p'-DDD and p,p'-DDT), HCHs (alpha-, beta-, gamma-isomers), chlordanes (trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor and oxychlordiane) and HCB (hexachlorobenzene were measured in liver, kidney and brain tissues of adult southern sea otters (Enhydra lutris nereis) found stranded along coastal California, USA, during 1992-96. The contamination pattern of organochlorines in sea otters from several locations was in the order of DDTs > PCBs > > CHLs > HCHs > > HCB, whereas those from Monterey Harbor contained greater concentrations of PCBs than of DDTs. Hepatic concentrations of PCBs and DDTs were in the ranges of 58-8700 and 280-5900 ng/g, wet weight, respectively, which varied depending on the geographic location. Sea otters collected from Monterey Harbor contained the greatest concentrations of PCBs and DDTs. In general, accumulation of DDTs CHLs and PCBs was greater in kidney than in liver, whereas that of HCHs was similar in both the tissues. The gender difference in organochlorine concentrations was less than those reported in cetaceans. The composition of DDTs, HCHs and CHLs compounds in sea otter tissues indicated no recent inputs of these compounds in coastal California. Sea otters that died from infectious diseases, neoplasia and emaciation contained higher concentrations of DDTs than those that died from trauma. (C) 1998 Elsevier Science Lid. All rights reserved.
  • GB Kim, H Nakata, S Tanabe
    ENVIRONMENTAL POLLUTION 99 (2) 255 - 261 0269-7491 1998 [Peer-reviewed]
     Scientific journal 
    The present study attempted to examine the in-vitro inhibition of hepatic microsomal P450 content and activity by butyltins in marine mammals and discussed on their possible effects in animals in the wild. Decreases in P450 content and the activities of ethoxyresorufin O-deethylase (EROD, catalyzed by CYP1A subfamily) and penthoxyresorufin O-depentylase (PROD, catalyzed by CYP2B subfamily) by tributyltin (TBT) were observed in in-vitro experiments using hepatic microsomes of a pinniped and a cetacean. Among P450 family, EROD activity is more sensitive to TBT than P450 content and PROD activity, indicating a specific mode of action of TBT on different P450 forms. On the other hand, dibutyltin and monobutyltin have no inhibitory effect on EROD activity at concentrations less than 0.5 mM, indicating that the inhibition of enzyme activity in hepatic microsome of marine mammal is mainly by TBT. TBT concentrations that affect P450 contents and activities are above 10 times higher than the values found in the liver of various marine mammals. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • Watanabe, I, Y Yamamoto, K Honda, Y Fujise, H Kato, S Tanabe, R Tatsukawa
    NIPPON SUISAN GAKKAISHI 64 (1) 105 - 109 0021-5392 1998/01 [Peer-reviewed]
     Scientific journal 
    Mercury concentrations were determined in the liver of Antarctic minke whale (Balaenoptera acutorostrata) collected during 1980-82 and 1984-86, and compared in view of age-dependent accumulation. No significant sexual and geographical variations were observed, while higher mercury concentrations were found in the Liver of Antarctic minke whales caught in the 1984-86 season rather than in 1980-82 by commercial whaling. Mercury concentration elevated with age until maturity and then revealed a steady state or slightly declined. However, the age showing maximum level of mercury was found to be older in 1984-86 than in 1980-82. This observation might be attributable to temporal changes in feeding amounts, resulting from disturbance of the Antarctic ecosystem such as uncontrolled management of whale resources in the past.
  • S Tanabe, M Prudente, T Mizuno, J Hasegawa, H Iwata, N Miyazaki
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 32 (2) 193 - 198 0013-936X 1998/01 [Peer-reviewed]
     Scientific journal 
    Hepatic butyltin concentrations were determined in 63 cetaceans belonging to 14 species and four pinnipeds belonging to two species collected from North Pacific and Asian coastal waters. Butyltin compounds (BTs) including tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MET) were detected in almost all the liver samples suggestive of its worldwide distribution. The elevated residues detected in coastal species and low concentrations found in off-shore species indicate a high degree of butyltin contamination in coastal waters than in the open sea. Mammals inhabiting waters of developed nations were found to contain higher BT concentrations compared with those collected from the waters proximal to developing countries. These observations strongly suggest serious BT contamination in the waters of developed countries than in developing nations at present. Among the samples collected off Japanese coastal waters, lower BT concentrations were found in pinnipeds compared with the cetaceans, suggestive of a possible difference in degradation capacities and excretory moulting between these two groups of animals. The estimated concentration ratio of BT in the liver of killer whale fetus to its pregnant mother was relatively low (0.015), indicative that transplacental transfer of BTs from the mother to her fetus is a deal less. Among the BT breakdown products, DBT was predominant in most of the liver samples analyzed, followed by TBT and MBT.
  • M Prudente, S Tanabe, M Watanbe, A Subramnian, N Miyazki, P Suarez, R Tatsukawa
    MARINE ENVIRONMENTAL RESEARCH 44 (4) 415 - 427 0141-1136 1997/12 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorines were determined in the blubber and melon of 11 species of adult male odontocetis collected front the North Pacific, Indian Ocean and nearby seas. Mean concentrations of DDs (33 mu g/g wet wt) were the highest followed by PCBs (32 mu g/g wet wt), chlordane compounds (CHLs: 3.7 mu g/g wet wt), HCHs (1.1 mu g/g wet wt), and HCB (0.32 mu g/g wet wt). Odontoceti species inhabiting temperate waters revealed maximum residual concentrations of these contaminants, and the elevated DDT and PCB residues detected seem to suggest that some of the present species might potentially, be at high risk. Relatively high DDT concentrations were found in tropical water species, which could be attributed to the current usage of DDT in the tropics and the less movable nature of this compound via long-range atmospheric transport. The HCH levels in animals inhabiting cold and temperate waters were higher than those inhabiting tropical waters, a result that was perhaps reflective of atmospheric transport from the tropical source to the northern sinks. A similar pattern was also observed in PCBs, CHLs and HCB, probably indicating the ongoing discharge of these compounds from mid-latitudes as well as those originating in tropical regions. (C) 1997 Elsevier Science Ltd.
  • S Kan-Atireklap, S Tanabe, J Sanguansin
    MARINE POLLUTION BULLETIN 34 (11) 894 - 899 0025-326X 1997/11 [Peer-reviewed]
     Scientific journal 
    Butylin compounds (BTs) including tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) were analysed in sediments collected from coastal areas of Thailand in 1995, Contamination by BTs have been widespread along the coastal areas with concentrations of MBT, DBT and TEST in surface sediments ranging from 7 to 410, 2 to 1900 and 4 to 4500 ng g(-1) (dry weight basis), respectively High TBT concentrations were associated with large commercial or far seas vessels areas, while the levels at high fishing boat and coastal mariculture areas were lower, Large commercial ship and fishing boat hulls might be significant sources of BT contamination in Thailand coastal waters, Degradation of TBT in sediments might he higher in tropics than in sub-tropical a;one, To our knowledge, this is a first report on the detection of BTs in sediments from Thailand, (C) 1997 Elsevier Science Ltd.
  • S Tanabe, B Madhusree, AA Ozturk, R Tatsukawa, N Miyazaki, E Ozdamar, O Aral, O Samsun, B Ozturk
    MARINE POLLUTION BULLETIN 34 (9) 712 - 720 0025-326X 1997/09 [Peer-reviewed]
     Scientific journal 
    The highly toxic coplanar PCBs and other isomers were determined in harbour porpoises and fish (porpoise diet) collected from the Turkish coastal water of the Black Sea, during 1993, The concentrations of total PCBs were found in the range of 5.0-34 mu g g(-1) wet wt in the blubber of porpoises, Highly chlorinated members such as IUPAC Nos 138, 153 and 180 were the dominant congeners, consisting of 41% of the total PCB concentrations, The mean total 2,3,7,8-TCDD toxic equivalents (TEQs) of 13 coplanar PCBs including non-, mono- and di-ortho congeners were 1400 pg g(-1) wet wt in the blubber of males and 300 pg g(-1) wet wt in females, The IUPAC No, 118 was the most contributing congener occupying about 60% of the total TEQs, The most toxic non-ortho chlorine substituted coplanar PCBs such as IUPAC No, 77, 126 and 169 were minor contributors and accounted for 7.8, 4.2 and 0.7%, respectively, of the total TEQs, The activities of PB and MC-type enzymes were found to be low in Black Sea harbour porpoises, suggesting long term accumulation and possible toxic effects of PCBs in this species. (C) 1997 Elsevier Science Ltd.
  • M Prudente, EY Kim, S Tanabe, R Tatsukawa
    MARINE POLLUTION BULLETIN 34 (8) 671 - 674 0025-326X 1997/08 [Peer-reviewed]
     Scientific journal
  • KS Guruge, H Iwata, H Tanaka, S Tanabe
    MARINE ENVIRONMENTAL RESEARCH 44 (2) 191 - 199 0141-1136 1997/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of butyltin compounds were determined in the kidney and liver of various seabirds collected from Japan, Korea, the North Pacific Ocean and the southern Indian Ocean. These compounds were detected in most of the samples, which indicated widespread contamination in higher trophic aquatic animals even in remote areas. The highest mean residue concentrations of butyltins in the kidney (300 ng/g wet wt) and liver (280 ng/g wet wt) were in common cormorants from Lake Biwa, Japan. Laysan albatross from the North Pacific Ocean accumulated higher butyltin residues in the liver (43 ng/g wet wt) among open-ocean birds. Even though the number of samples analysed was small, it can be suggested that birds inhabiting inland to coastal areas had higher exposure to butyltins than those in the ocean. To our knowledge, this is the first study reporting on butyltin pollution in seabirds in global terms. (C) 1997 Elsevier Science Ltd.
  • GB Kim, JW Anderson, K Bothner, JH Lee, CH Koh, S Tanabe
    BIOMARKERS 2 (3) 181 - 188 1354-750X 1997/05 [Peer-reviewed]
     Scientific journal 
    Sixty-seven sediment samples were collected from Kyeonggi Bay, Korea, including the mouth of Han River Incheon Harbor, the Namdong industrial complex, and the open sea. Collections were conducted in December, 1995 and samples were maintained frozen (-20 degrees C) until analysis. Dichloromethane extracts were analysed for their content of CYP1A1-inducing compounds with a P450RGS (reporter gene system) assay, and for polycyclic aromatic hydrocarbons (PAHs). Sediment samples were also analysed for organic carbon (OC) content and grain size, to aid in evaluating the relationship between contamination and physical nature of the sediments. The responses of the P450RGS assay to the sediment extracts were expressed as mu g of benzo[a]pyrene toxic equivalents per g dry weight (mu g g(-1) BaPTEQ), and these values correlated well (r(2)=0.624) with total PAHs. BaPTEQ values were also highly correlated with the OC content of the sediments. The determination of P450RGS BaPTEQ is a useful tool, because it is both a rapid and inexpensive means of assessing the potential toxicity of organic compounds in environmental sediment samples. These values represent an estimate of the levels of compounds in the sediment that are potentially available to organisms through chronic exposure to pore water or ingestion of benthic species, We believe BaPTEQ values are more useful than tables of specific PAH concentrations, if the purpose of the investigation is to either obtain a rapid screening of an area or to develop some form of ecological or human health risk assessment.
  • S Tanabe, B Madhusree, AA Ozturk, R Tatsukawa, N Miyazaki, E Ozdamar, O Aral, O Samsun, B Ozturk
    MARINE POLLUTION BULLETIN 34 (5) 338 - 347 0025-326X 1997/05 [Peer-reviewed]
     Scientific journal 
    A wide range of organochlorine residues were determined in the blubber of harbour porpoises from the Black Sea, Concentrations of DDTs (8.3-180 mu g g(-1) wet weight) were the highest followed by PCBs (1.6-39 mu g g(-1)), HCHs (1.5-17 mu g g(-1)), CHLs (0.11-2.4, mu g g(-1)) and HCB (0,057-0,61 mu g g(-1)). The composition of DDT and its metabolites was in the order of p,p'-DDE (46%), g,p'-DDD (34%), g,p'-DDT (46%) and o,p'-DDT (4%), A similar pattern was also observed in fish from the Black Sea. Relatively higher concentrations of g,p'-DDD in these animals suggested the reductive condition of the Black Sea resulting from organic waste pollution, The residue levels of organochlorines were lower in older female porpoises possibly due to lactational transfer of these contaminants to their calves, while in males the organochlorine concentrations were positively correlated with age, When compared with other cetaceans, the organochlorine residues in harbour porpoises showed a perceptible male-female difference. Pt is noteworthy that the contamination by DDTs and HCHs in the Black Sea harbour porpoises were elevated amongst a worldwide comparison of organochlorine residues in the same species. (C) 1997 Elsevier Science Ltd.
  • K Kannan, KA Maruya, S Tanabe
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 31 (5) 1483 - 1488 0013-936X 1997/05 [Peer-reviewed]
     Scientific journal 
    The use of Aroclor 1268 at a former chlor-alkali plant in coastal Georgia (United States) has resulted in extensive contamination of soils on-site and also of sediments in the adjacent brackish marsh. The concentrations of total polychlorinated biphenyls (PCBs) in soil and marsh sediments ranged between 9.6 and 567 mu g/g dry wt. A nearly 100-fold decline in total PCBs with distance away from the site suggests a high attenuation of PCBs by the marsh environment. Isomer-specific analysis of PCBs in Aroclor 1268 and in soils and sediments from the site revealed that a comparable proportion of octa- and nonachlorobiphenyl congeners, characteristic of the source, were present. The distribution of PCBs in marsh sediments was similar to that in Aroclor 1268, which suggests a high degree of stability of this PCB formulation in this environment. The estimated 2,3,7,8-TCDD equivalents of coplanar PCBs in soil and sediments were between 1.6 and 28.6 ng/g dry wt and also declined by 2 orders of magnitude along the contamination gradient; the non-ortho congener, IUPAC No. 126, contributed greater than 50% of the toxic equivalents in these samples.
  • JS Lee, S Tanabe, N Takemoto, T Kubodera
    MARINE POLLUTION BULLETIN 34 (4) 250 - 258 0025-326X 1997/04 [Peer-reviewed]
     Scientific journal 
    Residue levels of persistent organochlorines in deep-sea organisms collected from Suruga Bay, Japan, were determined, PCBs (polychlorinated biphenyls) were the predominant group of organochlorines ranging in concentrations from 380 to 2800 ng g(-1) on a lipid weight basis, DDTs (DDT and its metabolises) were the next most abundant organochlorine compounds followed by CHLs (chlordane compounds), HCHs (hexachlorocyclohexanes) and HCB (hexachlorobenzene). In comparison with coastal shallow water organisms, higher concentrations of HCHs were found in deep-sea organisms, while no significant difference was noted for other organochlorines, Organochlorine residue levels in Suruga Bay were comparatively lower than those in other deep-sea organisms reported elsewhere, The deep-sea organisms showed no consistent trend between organochlorine concentrations and food chain relationships, Lipid-dependent accumulation of organochlorines by equilibrium partitioning may be attributable to this residue pattern, Among DDT compounds, p,p'-DDE was the highest in most deep-sea organisms, Trans-nonachlor and B-HCH were the major constituents of CHLs and HCHs, respectively, in these organisms. (C) 1997 Elsevier Science Ltd.
  • H Iwata, S Tanabe, T Mizuno, R Tatsukawa
    APPLIED ORGANOMETALLIC CHEMISTRY 11 (4) 257 - 264 0268-2605 1997/04 [Peer-reviewed]
     Scientific journal 
    Although organotins are notorious man-made organometallic species introduced into the aquatic environment, no investigation had been concerned with contamination of higher trophic animals such as marine mammals until the last few years, Our recent work demonstrated the detection of butyltin compounds (BTCs), including mono- (MET), di-(DBT), and tri-butyltin (TBT) in marine mammals, This paper reviews ETC contamination in higher trophic animals, based on our recent publications, Analysis for BTCs showed significant accumulation in tissues and organs of three finless porpoises (Neophocaena phocaenoides) collected from Japanese coastal waters, More than 10 mu g of butyltin ions per gram on a wet weight basis were detected in the liver of a porpoise collected in the semi-closed sea, Distribution of BTCs in the tissues and organs of the porpoises showed a similar pattern to several other marine mammal species: higher concentrations in liver and kidney, and lower in muscle and blubber, In addition, tissues and organs from two water birds and one sea turtle species were also analyzed for BTCs, and their concentrations and compositions were compared among the species, The results showed that the distribution of these contaminants extends widely, not only to marine mammals but also to other higher trophic species, On the other hand, the composition of the BTCs exhibited a specific profile in each species, The ratios of hepatic concentrations of DBT or MBT to TBT for marine mammals were relatively lower than those of water birds and the sea turtle, indicating that metabolism and excretion of TBT may be less efficient in the mammalian species. (C) 1997 by John Wiley & Sons, Ltd.
  • KS Guruge, S Tanabe, M Fukuda, S Yamagishi, R Tatsukawa
    MARINE POLLUTION BULLETIN 34 (3) 186 - 193 0025-326X 1997/03 [Peer-reviewed]
     Scientific journal 
    Concentrations of organochlorines such as PCBs, DDTs, chlordanes (CHLs), HCHs and HCB were determined in the Liver of common cormorants from two different colonies to understand the current status of contamination and geographical differences, The birds from Shinobazu pond, central Tokyo, exhibited significantly higher OC levels than those in the Lake Biwa, Residue level of PCBs was the highest followed by the DDTs regardless of the locations and growth stages, CHLs and HCB were also higher in the Shinobazu pond adults and juveniles, whereas HCHs were comparable with the Lake Biwa, The OC levels, excluding PCBs, were relatively higher in regurgitated fish in Lake Biwa than Tokyo Bay fish, The inverse relation of bioaccumulation between fish and birds emphasized that cormorants from both colonies, at least, would have seasonal and preferential feeding habits in a widely extended area, The calculated biomagnification values showed that DDTs and CHLs had lowest and highest metabolic capacities, respectively, This study also made evident that present OC contamination levels in common cormorants may not pose a serious threat to their reproduction, However, contaminant related risk in cormorants, if any, could be higher in Shinobazu pond than that in Lake Biwa, (C) 1997 Elsevier Science Ltd.
  • S Aono, S Tanabe, Y Fujise, H Kato, R Tatsukawa
    ENVIRONMENTAL POLLUTION 98 (1) 81 - 89 0269-7491 1997 [Peer-reviewed]
     Scientific journal 
    Persistent organochlorines such as polychlorinated biphenyls (PCBs), DDTs, chlordane compounds (CHLs), hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) were determined in the blubber of minke whale and ifs diet collected from the Antarctic and the North Pacific Oceans. Residue levels of these compounds (except HCB) in minke whale from the Antarctic were apparently lower than those from the North Pacific. This is due to the lower levels of these pollutants in the southern hemisphere than in the northern hemisphere and the specific feeding habit of the minke whale from the Antarctic which feeds on lower trophic organisms, primarily euphausiids. The north-south difference for HCB residue levels was small, reflecting its dispersible nature through long-range atmospheric transport. Compositions of DDT and CHL compounds in minke whale from the Antarctic were similar to those from the North Pacific, However, the composition of HCH isomers was different between the Antarctic and the North Pacific as was observed in their diet, suggesting a larger or on-going usage of lindane in the southern hemisphere countries. In minke whale from the Antarctic, the elevated level of PCBs residues was noted during a period of 1984 to 1993, implying a continuous discharge of PCBs in the southern hemisphere. A similar discharge was also suggested in the North Pacific, while a decreasing contamination by DDTs was apparent. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • Takahashi, S, Tanabe, S, Kubodera, T
    Environmental Toxicology and Chemistry 31 (11) 3103 - 3109 1997 [Peer-reviewed]
  • Bathini Madhusree, Shinsuke Tanabe, Ayaka Amaha Öztürk, Ryo Tatsukawa, Nobuyuki Miyazaki, Emin Özdamar, Orhan Aral, Osman Samsun, Bayram Öztürk
    Fresenius' Journal of Analytical Chemistry 359 (3) 244 - 248 0937-0633 1997 [Peer-reviewed]
     Scientific journal 
    Concentrations of butyltin compounds (BTs) were determined in harbour porpoise (Phocoena phocoena) collected from the Turkish coastal waters of the Black Sea. Total butyltin compounds (Σ BTs) in the liver were in the range of 89-219 ng/g on a wet weight basis. The dibutyltin (DBT) residues were higher than those of tributyltin (TBT), suggesting the degradation of TBT to DBT in the liver and the metabolic capacity comparable to other marine mammals. Any sex difference and age-dependent accumulation of BTs residues were not found in harbour porpoises, but residue levels increased until maturity and then remained constant. When compared with other marine mammals, the present results indicate that the Black Sea is also contaminated with butyltin compounds, but to a lesser degree than coastal waters of developed nations. The biomagnification factor in harbour porpoises was 0.8, which was comparable with pinnipeds and lower than cetaceans. © Springer-Verlag 1997.
  • S Kanatireklap, S Tanabe, J Sanguansin, MS Tabucanon, M Hungspreugs
    ENVIRONMENTAL POLLUTION 97 (1-2) 79 - 89 0269-7491 1997 [Peer-reviewed]
     Scientific journal 
    In order to elucidate marine pollution by butyltins and organochlorine residues in coastal waters of Thailand, green mussels (Perna viridis) were collected in 1994 and 1995 and analyzed. Butyltin compounds, such as tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MET), were detected in most mussel samples, ranging from 4 to 800 ng g(-1) wet wt (as total). The composition of butyltin derivatives in green mussel was in the order of TBT > DBT > MBT. The results indicated that butyltin contamination was widespread, particularly in high boating areas and in coastal aquaculture facilities. Concentrations of organochlorine residues were much lower than of butyltin compounds. Among organochlorine residues examined, dichlorodiphenyltrichloroethane compounds (DDTs) were found to be the highest, followed by polychlorinated biphenyls (PCBs) > chlordane compounds (CHLs) > hexachlorocyclohexanes (HCHs) > hexachlorobenzene (HCB). To our knowledge, this is a first report on the detection of butyltin residues in Thailand coastal waters. (C) 1997 Elsevier Science Ltd.
  • KS Guruge, S Tanabe
    ENVIRONMENTAL POLLUTION 96 (3) 425 - 433 0269-7491 1997 [Peer-reviewed]
     Scientific journal 
    Isomer-specific accumulation of poly,chlorinated biphenyls (PCBs) including di-, mono-and non-ortho congeners and hepatic P-450 activities were determined in adult common cormorants from Lake Biwa, Japan. The mean total PCB levels in male and female birds were 7.2 +/- 6.1 and 2.1 +/- 0.74 mu g g(-1) wet wt, respectively, in the liver. The highly biomagnified congeners were IUPAC 126, 153, 169, 180 and 194, whereas a higher degree of biotransformation could be observed in both meta-para chlorine unsubstituted congeners in the cormorant liver. The estimated metabolic index also shotted that common cormorants had higher PB-type enzyme activities than some avian and marine mammals but poor MC-type enzyme activities. The concentrations of non-ortho coplanar congeners were in the order of IUPAC 126>IUPAC 169>IUPAC 77 with mean values 6.1 +/- 5.9, 1.3 +/- 1.4 and 0.43 +/- 0.26 ng g(-1) wet wt, respectively. The calculated mean 2,3,7,8-TCDD toxic equivalent (TEQ) concentration in cormorants was 1.8 +/- 1.7 ng g(-1) wet wt and Mas dominated by IUPAC 118, followed by IUPAC 126. A significant increase of ethoxyresorufin-O-deethylase (EROD) and pentoxyresorufin-O-deethylase (PROD) activities Mas observed with estimated TEQ of PCBs in the cormorants, suggesting that the current contamination level is sufficient for altering their biochemical responses. (C) 1997 Elsevier Science Ltd.
  • Deog Bae Lee, Maricar S. Prudente, Shinsuke Tanabe, Ryo Tatsukawa
    Toxicological and Environmental Chemistry 60 (1-4) 171 - 181 0277-2248 1997 [Peer-reviewed]
     Scientific journal
  • H Nakata, S Tanabe, R Tatsukawa, M Amano, N Miyazaki, EA Petrov
    ENVIRONMENTAL POLLUTION 95 (1) 57 - 65 0269-7491 1997 [Peer-reviewed]
     Scientific journal 
    Isomer specific concentrations of individual polychlorinated biphenyls (PCBs) including toxic non-ortho (IUPAC 77, 126, 169), mono-ortho (105, 118, 156) and di-ortho (137, 138, 153, 180) coplanar congeners were determined in the blubber of 40 Baikal seals (Phoca sibirica) and as their fish diet collected fr om Lake Baikal, Siberia. Residue levels of total PCBs in Baikal seals were noticeably high and comparable to those reported for seals from the North Sea, suggesting the recent usage of this compound in the watershed of Lake Baikal, Non-, mono-, and di-ortho coplanar congeners were also detected in Baikal seals and fish. An approach to estimate bioaccumulation profiles of PCB congeners revealed that the non-ortho PCBs, IUPAC 77, 126 and 169 seemed to be less persistent than other congeners, Furthermore, selective biotransformation of PCB congeners having either meta-para vicinal H atoms or both adjacent chlorinated meta-para and ortho-meta positions has been suggested. Comparison of 2,3,7,8-TCDD toxic equivalents (TEQ) of non-, mono- and di-ortho coplanar congeners in Baikal seals with those for other marine mammals suggested higher enrichment of mono-ortho congeners, particularly IUPAC 105 and 118, which contr ibuted significantly to the total TEQs in Baikal seals. Results imply that the TCDD-like toxicity is relatively serious in Baikal seals, because of the enrichment of these toxic PCB congeners in tissues. (C) 1997 Elsevier Science Ltd.
  • K. S. Guruge, S. Tanabe, M. Fukuda, S. Yamagishi, R. Tatsukawa
    Toxicological and Environmental Chemistry 58 (1-4) 197 - 208 0277-2248 1997 [Peer-reviewed]
     Scientific journal 
    The concentrations of butyltin compounds were determined in the kidney, liver and ventral feathers of common cormorants from two different population groups in Lake Biwa and Sinobazu pond, Japan. The Lake Biwa cormorants exhibited relatively higher contamination levels in the kidney than those in the Sinobazu pond. The ventral feathers of adult and juvenile cormorants from the Sinobazu pond showed elevated concentrations while in chicks liver accumulated the increased levels. Monobutyltin accumulated preferentially in feathers suggesting a specific binding capacity or higher metabolic rate during the physiologically active periods such as moulting and breeding. Total butyltin levels in the kidney were significantly correlated (r = 0.761, p < 0.0005) with those in liver. The accumulation of butyltin compounds (BTs) in ventral feathers showed a significant positive correlation with those in the internal tissues (kidney + liver) (r = 0.700, p < 0.001) of adult birds. This suggested that the body feathers can be used as an indicator to determine BTs in wild birds.
  • K. Kannan, K. Senthilkumar, B. G. Loganathan, S. Takahashi, D. K. Odell, S. Tanabe
    Environmental Science and Technology 31 (1) 296 - 301 0013-936X 1997/01 [Peer-reviewed]
     Scientific journal 
    Butyltin compounds, including mono- (MBT), di- (DBT), and tributyltin (TBT), were determined in the liver, kidney, and muscle of bottlenose dolphins (Tursiops truncatus) found stranded along the southeast U.S. Atlantic and Gulf coasts during 1989-1994. Total butyltin (BTs: MBT + DBT + TBT) concentrations in dolphin liver ranged between 110 and 11 340 ng/g (wet wt) with a mean value of 1400 ng/g. Butyltin concentrations in bottlenose dolphins were higher than those reported from other locations. The liver of a adult male dolphin collected in 1989 had the highest BT concentration (11 340 ng/g wet wt) reported. The concentrations of butyltins increased during the early life stages until maturity, for both sexes, and then tended to remain constant. Analysis of fish muscle collected from the Gulf of Mexico indicated the existence of recent inputs of TBT. The biomagnification factor of BTs in dolphins, on average, was 1.0 with the highest value of 6.8. In addition to polychlorinated biphenyls (PCBs), the presence of noticeable concentrations of TBT and DBT, which are potential immunosuppressing agents, might have also contributed to bottlenose dolphin mortality events in the U.S. Atlantic and Gulf coasts.
  • GB Kim, S Tanabe, R Tatsukawa, TR Loughlin, K Shimazaki
    ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 15 (11) 2043 - 2048 0730-7268 1996/11 [Peer-reviewed]
     Scientific journal 
    The present study was conducted to examine sex difference, age, and temporal trends of butyltin accumulation and its biomagnification in Steller sea lion (Eumetopias jubatus) collected from Alaska, USA, during 1976-1985 and from Hokkaido, Japan, during 1994-1995. Average concentration of total butyltin compounds (Sigma BTs) in the liver of Steller sea lion from Alaska (19 ng/g wet weight) was much lower than those from western and eastern Hokkaido, Japan (150 and 220 ng/g), respectively. This result suggests that Japanese coastal waters are contaminated with BTs in comparison with those of Alaska. In most samples, dibutyltin (DBT) residues were retained at higher levels than tributyltin (TBT), suggesting the degradation of TBT to DBT in the liver. Sex difference and age-dependent accumulation of BTs residues were not found in Steller sea lion. Similarly, no prominent temporal trend in BT concentrations was observed between 1976 and 1985. Nevertheless, the annual consumption of organotin compound was doubled in the United States during the same period. These results suggest that the butyltin compounds are degraded faster than the intake from diet in Steller sea lion. The biomagnification factor of BTs in Steller sea lion was low (0.15-4.6; mean, 0.6), indicating that this animal is unlikely to magnify BTs due to rapid degradation and excretion.
  • KS Guruge, S Tanabe, H Iwata, R Taksukawa, S Yamagishi
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 31 (2) 210 - 217 0090-4341 1996/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of butyltin compounds (BTs) were determined in various body tissues of common cormorants (Phalacrocorax carbo) collected from the Lake Biwa, Japan. Elevated concentrations of butyltins were detected in the feathers of cormorants. Among other organs and tissues, butyltin levels were also higher in the kidney (290 +/- 150 ng/g) and liver (270 +/- 260 ng/g), ranging from 115 to 544 ng/g and 142 to 1007 ng/g (wet wt basis), respectively. The accumulation of BTs in cormorant bodies was in the order of MBT > DBT > TBT and their organ specific burdens were in the order of muscle greater than or equal to feathers > skin > liver > rest of the tissues and organs. The higher levels of BTs residues in feather suggested the excretion of about one fourth of their body burden during a complete molting cycle, which has been a natural detoxification mechanism in these birds. Based on the whole body concentrations of BTs in cormorants (42-160 ng/g wet wt) and fish (10-55 ng/g wet wt) biomagnification factors were assessed to be in the range of 1.1-4.1. To our knowledge, this is the first fundamental study to substantially indicate the contamination and kinetics of BTs in wild birds.
  • GB Kim, S Tanabe, R Iwakiri, R Tatsukawa, M Amano, N Miyazaki, H Tanaka
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 30 (8) 2620 - 2625 0013-936X 1996/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of butyltins (BTs) in the liver and organochlorine compounds (OCs) in the blubber of Risso's dolphins collected off Taiji, Japan, in 1991 were determined. Mean and range concentrations (wet weight basis) of these compounds were 3.6 mu g/g (0.55-6.0 mu g/g) for BTs, 25 mu g/g (1.7-120 mu g/g) for PCBs, 17 mu g/g (0.45-77 mu g/g) for DDTs, 4.0 mu g/g (0.19-16 mu g/g) for CHLs, and 0.16 mu g/g (0.008-0.74 mu g/g) for HCHs. OCs concentrations increased with age in males in contrast to that in females, which showed a decreasing trend after maturity. On the other hand, no difference was observed in BT concentrations between male and female, which showed increasing levels until maturity (8-10 years) and then remained constant. It is suggested that, unlike OCs, BTs were less transferable to young ones in reproductive processes. Risso's dolphins showed higher biomagnification factor (about 6) than Steller sea lion (0.6), implying a slower excretion rate of BTs in cetaceans than in pinnipeds due to the lower degradation capacity of xenobiotics and the lack of physiological processes such as shedding of hair in cetaceans.
  • GB Kim, JS Lee, S Tanabe, H Iwata, R Tatsukawa, K Shimazaki
    MARINE POLLUTION BULLETIN 32 (7) 558 - 563 0025-326X 1996/07 [Peer-reviewed]
     Scientific journal 
    The present study was conducted to elucidate the specific distribution of butyltin (BT) compounds in various tissues and organs of Steller sea ions collected from coastal waters of Hokkaido, Japan. BT concentrations were an order of magnitude higher in the liver than in other tissues and organs except hair, whereas organochlorine (OC) compounds accumulated at two to three orders of magnitude higher in blubber than in other tissues. No relationship was observed between BT concentrations and the lipid content in tissues, while the levels of OCs were positively associated with the lipid content. The levels of BTs in hair (1500 ng g(-1) on a wet weight basis) were the highest of all the tissues analysed. Results also suggested that 25% of the total BT burden in the body was eliminated through shedding. Selective accumulation of BTs in liver and hair is attributed to its protein-binding capacity rather than lipophilicity. The discovery of high concentrations of BTs in hair implies their excretion by shedding in piliferous animals. Copyright (C) 1996 Elsevier Science Ltd
  • JS Lee, S Tanabe, H Umino, R Tatsukawa, TR Loughlin, DC Calkins
    MARINE POLLUTION BULLETIN 32 (7) 535 - 544 0025-326X 1996/07 [Peer-reviewed]
     Scientific journal 
    Organochlorine pesticides and polychlorinated biphenyls (PCBs) were determined in the blubber and liver of Steller sea lion collected from the bulk of Alaska and the Russian :Bering Sea, PCBs were the predominant organochlorines in the blubber, ranging in concentration from 5.7 to 41 mu g g(-1) (lipid weight) in males and from 0.57 to 16 mu g g(-1) in females. Concentrations of DDTs (DDT and its metabolites) in the blubber ranged from 2.8 to 17 mu g g(-1) in males and from 0.19 to 6.5 mu g g(-1) in females, The levels of chlordane compounds (CHLs) and hexachlorocyclohexanes (HCHs) were one to three orders of magnitude lower than those of PCBs and DDTs. The residue levels of PCBs, DDTs and CHLs in males increased with age, whereas in females they decreased sharply after maturity, suggesting the transfer of organochlorines in large quantities during lactation. Transfer rate of organochlorines through lactation was estimated to be 80% for PCBs and 79% for DDTs of the total body of adult female. Concentrations of organochlorines in the liver of the Steller sea lion from Alaska, on a lipid weight basis, were similar to those in the Blubber, In addition, liver showed age-dependent accumulation of PCBs, DDTs and CHLs, similar to that in the Blubber. The concentrations of all the organochlorines detected in the liver were clearly correlated with those in the blubber, indicating the lipophilic nature of organochlorines in accumulation and movement in the animal body, Residue levels of PCBs and DDTs in the liver of male Steller sea lions from the Bering Sea were significantly lower than those from Alaska, suggesting that Bering Sea animals have different foraging areas from the animals of the bulk of Alaska. Copyright (C) 1996 Elsevier Science Ltd
  • K Kannan, S Corsolini, S Focardi, S Tanabe, R Tatsukawa
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 31 (1) 19 - 23 0090-4341 1996/07 [Peer-reviewed]
     Scientific journal 
    Tributyltin (TBT) and its breakdown products, mono- (MBT) and dibutyltin (DBT) were determined in bottlenose dolphin (Tursiops truncatus), bluefin tuna (Thunnus thynnus thynnus) and blue shark (Prionace glauca) collected from the Italian coast of the Mediterranean Sea in 1992-1993. Concentrations of total butyltin (BTs) in the liver of dolphin (1,200-2,200 ng/g wet wt) were an order of magnitude higher than in the blubber (48-320 ng/g wet wt). TBT was the predominant butyltin species in the blubber while DBT accounted for an higher proportion in the liver of dolphins. Butyltin concentrations in bluefin tuna were lower than those in dolphins, with TBT highest in the muscle and DBT in the liver. Concentrations of BTs in blue sharks were lower than those in dolphin and tuna, with kidney having the highest concentrations. TBT was the predominant form of butyltin derivatives in all the tissues of shark. Accumulation of butyltin compounds in liver/kidney seems to be associated with the presence of proteins such as glutathione.
  • EY Kim, K Saeki, S Tanabe, H Tanaka, R Tatsukawa
    ENVIRONMENTAL POLLUTION 94 (3) 261 - 265 0269-7491 1996 [Peer-reviewed]
     Scientific journal 
    Total mercury (T-Hg), methyl mercury (MeHg) and selenium (Se) concentrations were determined to elucidate the relationship between Hg and Se levels in the liver of 10 seabird species. Highest concentrations of T-Hg (mean 267 mu g/g dry wt), MeHg (mean 25.5 mu g/g dry wt) and Se (mean 113 mu g/g dry wt) were in the liver of black-footed albatross (Diomedea nigripes). An equivalent molar ratio of 1:1 between T-Hg and Se was found in the liver of individuals which contain over 100 mu g Hg/g. However, such a relationship was unclear in other individuals which had relatively low Hg levels. This suggests that Se plays a sole in Hg detoxification for those individuals with high Hg. In seabird tissues, Hg and Se levels should be a most important factor determining the relationship between Hg and Se, and fluctuation of Hg burden through molting and the species-specific demethylation capacity would also influence their relationships. (C) 1997 Elsevier Science Ltd.
  • Watanabe, I, H Ichihashi, S Tanabe, M Amano, N Miyazaki, EA Petrov, R Tatsukawa
    ENVIRONMENTAL POLLUTION 94 (2) 169 - 179 0269-7491 1996 [Peer-reviewed]
     Scientific journal 
    Trace element concentrations (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Co and Hg) were determined in 60 Baikal seals and in fishes collected from Lake Baikal in 1992. Low levels of Hg and Cd were found in Baikal seals in comparison with those of marine mammals and it was due to their low concentrations in dietary fish. These results suggest that pollution by Hg and Cd was low in Lake Baikal and these toxic elements were unlikely to be the causative factors for mass mortality of Baikal seal in 1987-1988. Significant correlation of Hg concentration between hair and internal tissues suggested the use of hair for Hg monitoring in pinnipeds. Among essential elements, higher Fe and lower Cu levels were specifically found in the liver of Baikal seal, The noticeable accumulation of essential elements might be related to the unique and specific environment of Lake Baikal. (C) 1997 Elsevier Science Ltd.
  • EY Kim, H Ichihashi, K Saeki, G Atrashkevich, S Tanabe, R Tatsukawa
    ENVIRONMENTAL POLLUTION 92 (3) 247 - 252 0269-7491 1996 [Peer-reviewed]
     Scientific journal 
    Concentrations of four essential elements (Fe, Mn, Zn, and Cu) and two toxic metals (Cd and Hg) were determined in selected tissues of 11 seabird species collected in Chaun, northeast Siberia. In oldsquaw, arctic tern and herring gull, zinc concentrations were correlated with Cd concentrations. Cadmium concentrations in all the species were highest in kidney and Hg in liver. Cd levels in the liver and kidney of herring gulls were higher than those observed from other breeding areas. Similarly, Hg concentrations were also high in the liver of herring gull. High concentrations of Cd and Hg found in some birds from Chaun might have arisen from exposure on migration. Copyright (C) 1996 Elsevier Science Ltd
  • S Tanabe, P Kumaran, H Iwata, R Tatsukawa, N Miyazaki
    MARINE POLLUTION BULLETIN 32 (1) 27 - 31 0025-326X 1996/01 [Peer-reviewed]
     Scientific journal 
    The enantiomeric ratio of alpha-hexachlorocyclohexane (alpha-HCH) in blubber of 10 species of adult male small cetaceans has been determined by means of capillary gas chromatography using beta-cyclodextrin as a chiral stationary phase. The enantiomeric ratio of (+)-alpha-HCH/(-)-alpha-HCH ranged from 1.6 to 2.8, showing diverse values. Moreover, even in the same species, the ratios varied between animals collected from different localities. Dall's porpoise (Phocoenoides dalli) collected from the Bering Sea had enantiomeric ratios of 2.0-2.1 and others, from the North Pacific and Japan Sea, exhibited ratios ranging from 1.6-1.9. The ratios of beta-HCH concentration to total HCH concentration (beta-HCH/Sigma HCH) was linearly related to the enantiomeric ratios of alpha-HCH (r=-0.46, p<0.005). This may indicate that the metabolic capacity to degrade HCH isomers among cetaceans can be evaluated in terms of degradation of the (+)-alpha-HCH enantiomer. Present enantiomeric ratios were compared with earlier observations on various environmental samples and unbalanced degradation of (+)- and(-)-alpha-HCH enantiomers was suggested in small cetaceans.
  • H IWATA, S TANABE, T MIZUNO, R TATSUKAWA
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 29 (12) 2959 - 2962 0013-936X 1995/12 [Peer-reviewed]
     Scientific journal 
    Organotins are one of the most toxic chemicals in the aquatic environment. While contamination and toxic effects of organotin compounds in lower trophic aquatic organisms have been well-documented, no investigation has focused so far on higher aquatic organisms like marine mammals. We attempted to analyze butyltin compounds (BTCs), including mono-(MBTs), di- (DBTs), and tributyltin compounds (TBTs), in various tissues and organs of finless porpoise (Neophocaena phocaenoides) collected from Japanese coastal waters and detected these compounds in all the animals. The highest residue levels were found in the liver of a porpoise collected in the inland sea, recording more than 10 ppm BTCs on a wet weight basis. The composition of BTCs was different according to the tissues and organs with higher proportions of DBTs noticed in the liver and blood. Estimation of ETC burdens in tissues and organs indicated that muscle, liver, and blubber retained predominant portion of TBTs, DBTs, and MBTs. The occurrence of higher rates of TBTs on the whole implied the lower metabolic potential of porpoises to BTCs.
  • H NAKATA, S TANABE, R TATSUKAWA, M AMANO, N MIYAZAKI, EA PETROV
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 29 (11) 2877 - 2885 0013-936X 1995/11 [Peer-reviewed]
     Scientific journal 
    Organochlorine compounds (OCs) such as DDTs (DDT and its metabolites), PCBs (polychlorinated biphenyls), CHLs (chlordane compounds), and HCHs (hexachlorocyclohexanes) were determined in the blubber of Baikal seal (Phoca sibirica) and their fish diet collected from Lake Baikal in 1992. Residue levels of DDTs and PCBs were in the ranges of 4.9-160 mu g/g and 3.5-64 mu g/g on a lipid weight basis, respectively. The concentrations of CHLs and HCHs were approximately 1 or 3 orders of magnitude lower than those of DDTs and PCBs. Comparison of OC residue levels with those reported for other pinnipeds suggests that Baikal seal is highly contaminated species vulnerable to OC toxicity. A positive age-dependent accumulation of DDTs, PCBs, and CHLs was found in males, while a steady state observed in females suggested the transfer of these chemicals from mother to pup through gestation and lactation. On the basis of contaminant burdens in adult seals, it was estimated that an adult female Baikal seal transfers about 20% of its total DDTs and 14% of its total PCBs to the pup during a reproductive process. Based on the data from isomer-specific analysis of PCBs, it can be suggested that Baikal seals have a higher or comparable capacity to metabolize toxic contaminants than marine mammals, but it is apparently lower than terrestrial mammals, which seems to be a causative factor for the higher accumulation of OC residues in this species.
  • K KANNAN, S TANABE, R TATSUKAWA
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 29 (10) 2673 - 2683 0013-936X 1995/10 [Peer-reviewed]
     Scientific journal 
    Concentrations of persistent organochlorine residues were determined in fish collected from several locations in eastern and southern Asia and Oceania to identify the accumulation features of such residues in tropical aquatic organisms and to elucidate their distribution in tropical developing countries. DDT and its derivatives (DDTs) were the predominantly identified compounds in most locations. In general, the concentrations of organochlorines in tropical fish were lower than those in fish of the temperate regions. Residue levels in fish showed little spatial variability, as reported for tropical sediments. This is different from the patterns observed for air and water in which higher concentrations occur in tropical latitudes compared to mid-latitudes. Compilation of limited available data on the organochlorine residue levels in fish in tropical Asian countries seemed to indicate little temporal variability due to the low levels of accumulation in aquatic organisms, despite the continuous use of these compounds. A short residence time of semivolatile organochlorines in the tropical aquatic environment results in lower levels of accumulation of residues in fish. Examination of walleye pollock (Theragra chalcogramma) collected from the Bering Sea indicated that organochlorine residue levels are declining in temperate water bodies near the Arctic Ocean in recent years.
  • K KANNAN, S TANABE, R TATSUKAWA
    BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 55 (4) 510 - 516 0007-4861 1995/10 [Peer-reviewed]
     Scientific journal
  • S CORSOLINI, S FOCARDI, K KANNAN, S TANABE, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 29 (1) 61 - 68 0090-4341 1995/07 [Peer-reviewed]
     Scientific journal 
    The general exposure of humans and foxes to polychlorinated biphenyls (PCBs) and DDT in Italy was determined by analysis of adipose tissue samples collected from 1991-1992. Sigma PCB concentrations varied between 1.0 and 2.6 mu g/g (wet wt.). Sigma DDT concentrations ranged from 1.6 to 5.0 mu g/g (wet wt.). About thirty-five PCB congeners were identified in most samples. PCB congeners of IUPAC Nos. 138, 153, and 180 were the most abundant compounds, accounting for an average of 50% of the Sigma PCBs in humans and 64% in foxes. Generally, higher chlorinated biphenyls and those with a 2,4,5-chlorine substitution in one ring and at least one substitution in the 4-position of the other ring were preferentially accumulated. Coplanar PCB congeners were detected at considerable concentrations and there is no sign of decline in their concentrations with respect to previously reported data. IUPAC Nos. 118, 156 and 126 were the main contributors to toxicity in humans and foxes. The significant contribution of mono-ortho congeners in humans and non-ortho congeners in foxes suggests that differences in metabolic potential may affect the PCB toxicity pattern.
  • K KANNAN, S TANABE, R TATSUKAWA
    CHEMOSPHERE 30 (5) 925 - 932 0045-6535 1995/03 [Peer-reviewed]
     Scientific journal 
    Concentrations of phenyltins were determined in horseshoe crabs, Tachypleus tridentatus collected from Japanese coastal waters. Concentrations of Sigma PT in the crab hepatopancreas ranged from 77 to 12,410 ng/g (wet wt) which were, on average, 2-fold higher than those of butyltins. Presence of considerable levels of phenyltins in eggs suggested oviparous transfer effecting future generations. Transfer rates of phenyltins via eggs were proportional to corresponding burden in the hepatopancreas. The bioconcentration factors of TPT in the crab hepatopancreas were in the ranges of 8-44 X 10(4). Relatively lower concentrations of DPT than TPT suggested lower rates Of metabolism by Tachypleus. High concentrations of phenyltins and butyltins in horseshoe crabs may have serious implications for their survival, particularly at their early life stages.
  • Iwata, H, Tanabe, S, Ueda, K, Tatsukawa, R
    Environmental Science and Technology 29 (2) 792 - 801 2220-0290 1995/03 [Peer-reviewed]
  • K Kannan, S Tanabe, R Tatsukawa, RJ Williams
    INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY 61 (4) 263 - 273 0306-7319 1995 [Peer-reviewed]
     Scientific journal 
    Concentrations of mono- (MET), di- (DBT) and tributyltin (TBT) were determined in the muscle and liver of fish collected from Australia, Papua New Guinea and the Solomon Islands. Butyltin concentrations ranged from below the limit of detection to 47 ng g(-1) in muscle and 6.5 to 570 ng g(-1) wet wt in liver. Liver was found to accumulate higher concentrations of butyltins than muscle. Butyltin residues in tissues were not positively correlated with lipid content. Monobutyltin was the predominant species in all samples. The daily dietary intake of butyltins by Australians via fish was estimated to be 377-416 ng person(-1) day(-1), lower than is believed to cause health problems.
  • K KANNAN, S TANABE, H IWATA, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 90 (3) 279 - 290 0269-7491 1995 [Peer-reviewed]
     Scientific journal 
    Concentrations of butyltin residues were determined in muscle tissue of fish collected from local markets and sea food shops in India, Bangladesh, Thailand, Indonesia, Vietnam, Taiwan, Australia, Papua New Guinea and the Solomon Islands. Contamination levels were determined in the Asia-Pacific region and human exposure was estimated. Similarly, corresponding liver samples of fish muscle collected in Australia, Papua New Guinea and the Solomon Islands were analyzed to obtain information on partitioning of butyltin compounds between muscle and liver tissues. Butyltin compounds were detected in most of the samples which suggested widespread contamination in Asia and Oceania. The concentrations of butyltin compounds were, on average, an order of magnitude higher in liver than in muscle. Residue concentration of Sigma butyltin in liver was found to be correlated significantly (p < 0.02) with those in muscle. Intensive ship-scrapping activities, sewage disposal and antifouling paints are considered the major sources of butyltins in this region. Increased proportions of MBT over DBT and TBT in samples from most locations indicated degradation of TBT to MBT in fish tissues during storage at 4 degrees C in the dark over 1-2 years. The possibility that fish have been subject to increased exposure to MBT and that TBT degrades to MBT quite rapidly in tropical environments are also considered. Butyltin concentrations in fish from Asia and Oceania were lower than those reported for Japan, Canada and the USA. Although the number of samples analyzed from each country was small, it is tentatively suggested that intake of butyltins by humans via consumption of fish in these countries was < 25% of the tolerable daily intake of 250 ng kg bw(-1) day(-1). To our knowledge, this is the first study reporting on butyltin pollution in developing Asian countries.
  • S CORSOLINI, S FOCARDI, K KANNAN, S TANABE, A BORRELL, R TATSUKAWA
    MARINE ENVIRONMENTAL RESEARCH 40 (1) 33 - 53 0141-1136 1995 [Peer-reviewed]
     Scientific journal 
    Bottlenose and Risso's dolphins found dead along the Italian coast in 1992 were analysed for the presence of PCB isomers and DDT High concentrations of PCBs (90-1400 mu g/g wet wt) were detected in the blubber of stranded carcasses. The concentrations were higher than those found in animals showing reproductive failure and physiological impairment following prolonged PCB exposure, suggesting that the contamination by PCBs as well as DDT may be a major causative factor for the large-scale deaths of dolphins in the Mediterranean Sea. The 2,3,7,8-TCDD toxic equivalents estimated for bottlenose and Risso's dolphins were 18.8 and 20.8 ng/g, respectively, with a major contribution from mono-ortho PCBs. The mono-ortho congeners of IUPAC Nos 105, 118 and 156 accounted for most of the toxicity exerted by PCBs in these dead dolphins. An increase in the proportion of non-ortho coplanar PCB congener of IUPAC No. 169 to No. 126 with an increase in the total PCB concentration in the blubber suggested a strong induction of drug metabolizing enzymes. It is possible to use CB-169/CB-126 concentration ratio to indicate whether there has been a strong activation of cytochrome P450 enzyme system in severely exposed/contaminated dolphin populations. The total PCB concentrations in the adipose fat of sharks from Italian coasts ranged from 70 to 4000 ng/g wet wt and that of DDT from 14 to 300 ng/g wet wt. In bluefin tuna, the total PCB and DDT concentrations were 170-2200 and 56-780 ng/g wet wt, respectively. These values were comparable to those reported for the same species in the Mediterranean Sea during the 1970s, suggesting the existence of PCB sources near this marine ecosystem.
  • K KANNAN, Y YASUNAGA, H IWATA, H ICHIHASHI, S TANABE, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 28 (1) 40 - 47 0090-4341 1995/01 [Peer-reviewed]
     Scientific journal 
    Concentrations of heavy metals, organochlorine pesticides, polychlorinated biphenyls and organotins were determined in horseshoe crabs, Tachypleus tridentatus, collected from Japanese coastal waters. Heavy metal concentrations were high in the hepatopancreas, gill and egg. Residue levels of heavy metals were comparable to those recorded in most benthic organisms from Japanese coastal waters. Organochlorine concentrations were detected at a few ng/g acid the residue pattern followed the order of polychlorinated biphenyls (PCBs) > chlordane compounds (CHLs) > hexachlorocyclohexanes (HCHs) > dichlorodiphenyltrichloroethane (DDTs) > hexachlorobenzene (HCB). Butyltin concentrations were high in the hepatopancreas, ranging from 350-2,270 ng/g in Hakata Bay and 570-5,000 ng/g (on a wet wt basis) in Habu Bay. Elevated concentrations of butyltins were also detected in the eggs of horseshoe crabs. High accumulations of butyltins in horseshoe crabs may pose a serious threat to their survival and therefore needs immediate attention to prevent their extinction.
  • H IWATA, S TANABE, M ARAMOTO, N SAKAI, R TATSUKAWA
    MARINE POLLUTION BULLETIN 28 (12) 746 - 753 0025-326X 1994/12 [Peer-reviewed]
     Scientific journal 
    Three surface sediments and two sediment cores were collected from the Gulf of Alaska, Bering Sea and Chukchi Sea, and analysed for persistent organochlorines (OCs). The geographical distributions of OCs showed different patterns according to their physicochemical properties. The concentrations of HCHs and HCB revealed rather uniform distribution, suggesting their more transportable nature in long-range atmospheric transport. On the other hand, DDTs and PCBs were predicted to be less transportable via the atmosphere due to the decreasing trends of residue levels in sediments from south to north. The OC profiles in the sediment core from the Gulf of Alaska which seemed to be preserved without turbation revealed the elevated residue levels from bottom to surface layers. This implies that the aerial inputs of OCs in the cold ocean are still continuing significantly. The accumulation rates of OCs into sediments were rather smaller than the atmospheric inputs, indicating that the residue levels in water bodies are unlikely to decrease rapidly in the near future.
  • H IWATA, S TANABE, N MIYAZAKI, R TATSUKAWA
    MARINE POLLUTION BULLETIN 28 (10) 607 - 612 0025-326X 1994/10 [Peer-reviewed]
     Scientific journal 
    The blubber samples of eight species (12 specimens) of marine mammals caught between 1981 and 1993 in seas surrounding Japan and in the Indian, North Pacific and Antarctic Oceans, were analysed for butyltin compounds (BTCs). The column chromatography using dry florisil and acetonitrile enabled isolation of BTCs from lipids in fatty tissues like blubber, and led to the reliable analysis with efficient recoveries for these contaminants. BTCs were detected in all the animals except a minke whale from the Antarctic Ocean. The highest residue levels were found in a finless porpoise from the Seto-inland Sea, Japan with a BTC concentration of 770 ng g-1 on wet wt basis. Geographical distribution of the BTC concentrations in marine mammals showed a decreasing trend from the coastal to the open seas, indicating the presence of larger pollution sources nearby the coastal regions. Compositions of the BTCs in the blubber of finless porpoises seemed to be different from those found in aquatic organisms of lower trophic levels. Lower contributions of dibutyltins to the total BTCs in the blubber suggest the presence of their specific metabolic pathways. To our knowledge, this is the first report on the detection of BTCs in marine mammals.
  • K KANNAN, S TANABE, RJ WILLIAMS, R TATSUKAWA
    SCIENCE OF THE TOTAL ENVIRONMENT 153 (1-2) 29 - 49 0048-9697 1994/08 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorinated biphenyls (PCBs), DDT and its metabolites (DDTs), HCH isomers (HCHs), chlordane compounds (CHLs), aldrin, dieldrin, heptachlor, heptachlor epoxide and HCB were determined in a wide variety of foodstuffs collected from different locations in Australia, Papua New Guinea and the Solomon Islands. Elevated levels of PCBs, CHLs, DDTs and dieldrin were detected in most of the foodstuffs of animal origin. Fish samples collected near the coast of Sydney recorded noticeable concentrations of PCBs, CHLs and DDTs. PCB contamination was generally prominent in samples collected in urban areas, whereas organochlorine pesticides were distributed uniformly throughout Australia. The widespread usage of CHLs was evident from the composition of its compounds in various foods while HCHs and DDTs were found to have been used sporadically in space and time. For the most part, residue levels of organochlorines in foodstuffs were below the tolerance limits established by national and international health organizations. The exception was CHLs in some fish samples, which exceeded the maximum residue limits recommended by the National Health and Medical Research Council of the Australian government. Although the number of samples analysed in each class of foods is small for the purpose of estimating human dietary exposure, we tentatively conclude that the dietary intake of PCBs in Australia was higher than those observed in most developed and developing nations, whereas the intake of organochlorine pesticides was higher than in developed nations but lower than in developing countries. Meat products contributed to the higher dietary intakes of most of the organochlorines. The contamination pattern and the residual concentrations of organochlorines in foodstuffs of Papua New Guinea and the Solomon Islands resembled those observed in Australia.
  • J FALANDYSZ, K KANNAN, S TANABE, R TATSUKAWA
    BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 53 (2) 267 - 273 0007-4861 1994/08 [Peer-reviewed]
     Scientific journal
  • Organochlorine pesticides and polychlorinated biphenyls in cod-liver oils: North Atlantic, Norwegian Sea, North Sea and Baltic Sea.
    Falandysz, J, Kannan, K, Tanabe, S, Tatsukawa, R
    North Sea and Baltic Sea. Ambio 23 ((4/5)) 288 - 293 0044-7447 1994/07 [Peer-reviewed]
  • J FALANDYSZ, N YAMASHITA, S TANABE, R TATSUKAWA
    SCIENCE OF THE TOTAL ENVIRONMENT 149 (1-2) 113 - 119 0048-9697 1994/06 [Peer-reviewed]
     Scientific journal 
    Adipose tissue of inhabitants of the Gdansk city located at the southern coast of the Baltic Sea and of the province of Skierniewice of inland Poland have been investigated for congeners of polychlorinated biphenyls (PCBs) by the capillary GC-MS technique. PCB IUPAC No. 153 was a high contributor of the congener occupying 23% of the total PCB content, and together with No. 138 of 18% and No. 180 of 13% were the most prevalent members. Samples taken from Gdansk citizens in 1990 contained 1.5 +/- 1.3 mug/g of total PCBs on a fat weight basis while the citizens from the province of Skierniewice, sampled in 1979, contained 1.2 +/- 0.4 mug/g, which seemed to indicate a persistent PCB exposure in Poland. Among Gdansk citizens, randomly selected autopsy samples of liver cancer from dead persons contained 4.7 mug/g of PCBs, while in all other samples the level was between 0.75 and 1.9 mug/g of PCBs. TCDD TEQ of 13 detectable coplanar members of PCBs in adipose tissue of Gdansk, and Skierniewice inhabitants, was 210 and 190 pg/g on a lipid weight basis, respectively, including 45 and 59 pg/g of non-ortho, 142 and 110 pg/g of mono-ortho and 24 and 16 pg/g of di-ortho chlorobiphenyls. A fingerprint of chlorobiphenyl composition in the samples examined was virtually the same for human adipose tissue taken in 1990 from the coastal city of Gdansk and in 1979 from the inland province of Skierniewice, in spite of geographic variations and sampling intervals.
  • J FALANDYSZ, S TANABE, R TATSUKAWA
    SCIENCE OF THE TOTAL ENVIRONMENT 145 (3) 207 - 212 0048-9697 1994/05 [Peer-reviewed]
     Scientific journal 
    Five samples of cod-liver oil of Baltic origin, collected between 1971 and 1989, have been analysed for 15 selected polychlorinated biphenyl (PCB) congeners including the ten most toxic non-, mono- and di-ortho coplanar, IUPAC nos. 60, 77, 105, 118, 126, 138, 169 and 170 and another five highly bioaccumulative members (IUPAC nos. 28 + 32, 52, 101, 153 and 180). The method of measurement was capillary GC-MS. Cod-liver oils collected in 1971, 1975, 1980, 1985 and 1989 contained 3.0, 2.5, 6.7, 2.9 and 3.1 mug g-1 respectively, of selected PCBs (IUPAC nos. 28 + 32, 52, 101, 138, 153 and 180). The concentration of total PCBs in these oils were 8.0, 6.7, 17, 8.0 and 9.5 mug g-1, respectively for the years 1971-89, which indicates both persistency and steady state of these pollutants in the Baltic Sea. These cod-liver oils also showed high concentrations of the ten most toxic coplanar PCBs; their TEQ-values (Safe, 1990) were between 900 and 2300 ug g-1. 2,3',4,4',5-pentachlorobiphenyl (IUPAC no. 118), 2,3,3',4,4'-pentachlorobiphenyl (IUPAC no. 105) and 3,3',4,4',5-pentachlorobiphenyl (IUPAC no. 126) contributed most to the total TEQs of the ten coplanar members, occupying 47, 19 and 17%, respectively (totally 83%). A possible intake of these toxic PCBs from cod-liver oil by children or adults was estimated to be between 4.5 and 35 pg TEQ daily and for total PCBs between 34 and 260 ug daily. In the light of these observations cod-liver oil of Baltic origin, processed in Poland. poses concern to human health as it contains very high concentrations of toxic coplanar and total PCBs.
  • J FALANDYSZ, N YAMASHITA, S TANABE, R TATSUKAWA, L RUCINSKA, K SKORA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 26 (3) 267 - 272 0090-4341 1994/04 [Peer-reviewed]
     Scientific journal 
    Individual congeners of polychlorinated biphenyls (PCBs), including the highly toxic non-ortho coplanar 3,3',4,4'-tetrachlorobiphenyl (IUPAC No. 77), 3,3',4,4',5-pentachlorobiphenyl (IUPAC No. 126), and 3,3',4,4',5,5'-hexachlorobiphenyl (IUPAC No. 169), and their mono- and di-ortho analogs, have been identified and quantified in the blubber, liver, and muscles of three female common porpoise Phocoena phocoena collected from the Puck Bay (inner Gulf of Gdansk, Poland) in 1989-1990, to elucidate actual concentrations and toxic potential. The total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent for 13 coplanar PCBs in blubber was 1,500 +/- 470 pg/g wet wt. 2,3',4,4',5-Pentachlorobiphenyl (IUPAC No. 118) was the most contributing individual and occupied between 57 and 67% in total toxic equivalent of coplanar PCBs in blubber, while 2,2',4,4',5,5'-hexachlorobiphenyl (IUPAC No. 153), 2,3,3',4,4'-pentachlorobiphenyl (IUPAC No. 105) and 2,2',3,4,4',5'-hexachlorobiphenyl (IU-PAC No. 138) comprised between 9.5-14, 7.6-11.5, and 7.2-11.0%, respectively (totally 82-95%), and 2,3,3',4,4',5-hexachlorobiphenyl (IUPAC No. 156) was absent. A potentially most toxic non-ortho PCB members such as 3,3',4,4',5-pentachlorobiphenyl, 3,3',4,4',5,5'-hexachlorobiphenyl and 3,3',4,4'-tetrachlorobiphenyl were only minor contributors, altogether occupying between 1.0 and 14.5% in total TEQ of coplanar PCBs. Concentrations of total PCBs in lipids of the blubber ranged from 26 to 47 mug/g and were comparable or lower than reported earlier for common porpoises from the Baltic Sea, North Sea, and North Atlantic by other authors.
  • J FALANDYSZ, K KANNAN, S TANABE, R TATSUKAWA
    MARINE POLLUTION BULLETIN 28 (4) 259 - 262 0025-326X 1994/04 [Peer-reviewed]
  • K KANNAN, S TANABE, R TATSUKAWA, RK SINHA
    TOXICOLOGICAL AND ENVIRONMENTAL CHEMISTRY 42 (3-4) 249 - 261 0277-2248 1994 [Peer-reviewed]
     Scientific journal 
    Concentrations of PCBs (including non-ortho coplanar congeners), DDTs, HCHs, HCB, aldrin, dieldrin, heptachlor, heptachlor epoxide and chlordanes were determined in river dolphins from the Ganges, India. Residue levels of DDTs were the highest followed by PCBs and HCHs. Noticeable amounts of toxic non-ortho coplanar PCBs were also detected in the blubber. A continuing exposure of the Ganges biota to organochlorine chemicals was found to be evident. The observed isomer/metabolite pattern indicated that river dolphins exhibit a lower metabolic capacity to organochlorines as documented for other small cetaceans in the marine ecosystem. HCHs and CHLs were considered to be metabolized to a small extent, while PCBs and DDTs were the least metabolizable compounds by river dolphins. The degree of contamination, proximity to pollution source and the metabolic ability of river dolphins found in the present study suggest that river dolphins are at greater risk from environmental contamination by organochlorines than marine cetaceans.
  • S TANABE, JK SUNG, DY CHOI, N BABA, M KIYOTA, K YOSHIDA, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 85 (3) 305 - 314 0269-7491 1994 [Peer-reviewed]
     Scientific journal 
    The present study was conducted to determine the residue levels of persistent organochlorines such as PCB homologues, DDT and its metabolites, and HCH isomers in the ventral blubber of female northern fur seal (Callorhinus ursinus) collected off Sanriku, the Pacific coast of northern Japan, since 1971. Among the organochlorines examined, the concentrations of PCBs and DD Ts were found to be high in all samples. The residue levels of these two contaminants showed a drastic reduction following maturity and then a slight increase after the retirement from pregnancy/menopause. Temporal variation of PCB and DDT residues showed maximum levels around 1976 and then decreased, whereas HCH residue levels revealed a very slow declining pattern. Considering the concentrations and compositions of the residues, the northern fur seal is likely to be exposed to organochlorine contamination deriving from global terms. In this context, continuous contamination has been foreseen with regard to PCB and HCH residues. The pattern of organochlorine residues indicated that the northern fur seal has higher metabolic capacity than Dall's porpoise, while it is comparable to those of larga seal and Steller sea lion.
  • H IWATA, S TANABE, N SAKAI, A NISHIMURA, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 85 (1) 15 - 33 0269-7491 1994 [Peer-reviewed]
     Scientific journal 
    Persistent organochlorines in air, river water and sediment samples were analysed from eastern and southern Asia (India, Thailand, Vietnam, Malaysia, Indonesia) and Oceania (Papua New Guinea and Solomon Islands) to elucidate their geographical distribution in tropical environment. The concentrations of organochlorines in these abiotic samples collected from Taiwan, Japan and Australia were also monitored for comparison. Atmospheric and hydrospheric concentrations of HCHs (hexachlorocyclohexanes) and DDTs (DDT and its metabolites) in the tropical developing countries were apparently higher than those observed in the developed nations, suggesting extensive usage of these chemicals in the lower latitudes. CHLs (chlordane compounds) and PCBs (polychlorinated biphenyls) were also occasionally observed at higher levels in the tropics, implying that their usage area is also expanding southward. Distribution patterns of organochlorines in sediments showed smaller spatial variations on global terms, indicating that the chemicals released in the tropical environment are dispersed rapidly through air and water and retained less in sediments. The ratios of organochlorine concentrations in sediment and water phases were positively correlated with the latitude of sampling, suggesting that persistent and semivolatile compounds discharged in the tropics tend to be redistributed on a global scale.
  • K KANNAN, S TANABE, A BORRELL, A AGUILAR, S FOCARDI, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 25 (2) 227 - 233 0090-4341 1993/08 [Peer-reviewed]
     Scientific journal 
    Isomer-specific concentrations of polychlorinated biphenyls (PCBs) including planar, mono- and di-ortho congeners and concentrations of DDT were determined in striped dolphins affected by a morbillivirus epizootic in the western Mediterranean in 1990. Extremely high concentrations of PCBs ranging from 94 to 670 mug/g (wet wt) were detected in the blubber. Similarly, DDT concentrations were high, between 22 and 230 mug/g (wet wt). The concentrations of three non-ortho coplanar PCBs were 43 (3,3',4,4'-TCB), 6.8 (3,3',4,4',5-P5CB), and 7.8 (3,3',4,4',5,5'-H6CB) ng/g (wet wt), respectively, the highest residue levels reported to date. The estimated 2,3,7,8-TCDD toxic equivalents of non-, mono- and di-ortho PCB congeners in striped dolphins were several times higher than those observed for other marine mammals and humans. Mono-ortho congeners contributed greater 2,3,7,8-TCDD toxic equivalents than non-ortho members. The higher ratio of 3,3',4,4',5,5'-H6CB/3,3',4,4',5-P5CB (IUPAC 169/126) suggested a strong induction of mixed function oxidase enzymes and highlighted the possibility of using this ratio as an index for risk assessment of PCB contamination in marine mammals. Elevated concentrations of PCBs may have played a role in the immune depression in striped dolphins, ultimately leading to the development of morbillivirus disease.
  • S TANABE, A SUBRAMANIAN, A RAMESH, PL KUMARAN, N MIYAZAKI, R TATSUKAWA
    MARINE POLLUTION BULLETIN 26 (6) 311 - 316 0025-326X 1993/06 [Peer-reviewed]
     Scientific journal 
    Blubber samples of 12 accidentally netted dolphins from the coastal waters of Porto Novo, southeast coast of India were monitored to assess the persistent organochlorine (HCHs, DDTs, PCBs, and HCB) contamination in these animals. SIGMADDT concentrations ranked first, followed by PCBs, SIGMAHCH, and HCB. HCHs were detected for the first time in dolphins from the tropical waters. The variations in residue levels could be attributed to the physicochemical and biochemical properties of the above compounds. International comparison of residue levels in cetaceans in the recent decade revealed that DDT concentrations in Indian dolphins were comparable to those from other localities whereas PCB levels were low. The continuing contamination by these persistent organochlorines and their toxic effects in tropical cetacean species is predicted in the future.
  • H IWATA, S TANABE, R TATSUKAWA
    MARINE POLLUTION BULLETIN 26 (6) 302 - 305 0025-326X 1993/06 [Peer-reviewed]
  • H IWATA, S TANABE, N SAKAL, R TATSUKAWA
    ENVIRONMENTAL SCIENCE & TECHNOLOGY 27 (6) 1080 - 1098 0013-936X 1993/06 [Peer-reviewed]
     Scientific journal 
    Concentrations of organochlorines such as hexachlorocyclohexanes (HCHs), DDTs, chlordanes, and PCBs were determined in the air and surface water from various oceans in 1989-1990, for understanding their recent distribution and the role of ocean in the long-range atmospheric transport and fate on global terms. The atmospheric concentrations were found to be still higher in the Northern Hemisphere than in the Southern Hemisphere, although the distribution pattern suggested the shift or expansion of their major sources from the mid to low latitudes during the last decade. In surface water, HCHs showed a considerable contamination over 40-degrees-N, whereas DDTs were higher near tropical Asia. Chlordanes and PCBs exhibited rather uniform distributions in both the hemispheres. Estimations of fluxes by gas exchange across the air-water interface gave insight into the dispersal of organochlorines through oceanic atmosphere depending on their Henry's law constants and the tendency of more transportable ones to deposit into the cold waters as an ultimate sink.
  • J FALANDYSZ, K KANNAN, S TANABE, R TATSUKAWA
    BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 50 (6) 929 - 934 0007-4861 1993/06 [Peer-reviewed]
     Scientific journal
  • K KANNAN, J FALANDYSZ, S TANABE, R TATSUKAWA
    MARINE POLLUTION BULLETIN 26 (3) 162 - 165 0025-326X 1993/03 [Peer-reviewed]
  • K KANNAN, RK SINHA, S TANABE, H ICHIHASHI, R TATSUKAWA
    MARINE POLLUTION BULLETIN 26 (3) 159 - 162 0025-326X 1993/03 [Peer-reviewed]
  • BG LOGANATHAN, S TANABE, Y HIDAKA, M KAWANO, H HIDAKA, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 81 (1) 31 - 39 0269-7491 1993 [Peer-reviewed]
     Scientific journal 
    Trend monitoring of organochlorine contaminants, viz. PCBs, DDTs, HCHs and CHLs, was carried out by using formalin-preserved adipose tissue of Japanese males from 1928 through 1985 for understanding the long-term trends in their contamination levels. The highest residual concentrations were observed during the periods of maximum production (or import) and usage of these compounds in Japan. Time trends of the contaminants varied with the usage pattern and their physico-chemical properties. Effectiveness of government regulations on the production and use of organochlorines was seen faster in the case of DDTs and HCHs, which showed a prominent declining trend in their residues, whereas PCB levels exhibited a continuing increase and maintained a steady state even after two decades of a ban on their production, indicating that the exposure to PCBs is still prevailing. Generally, in terms of the spatial view, unlike aquatic fauna from the point-source environment (aquatic ecosystem) humans in the non-point-source environment (terrestrial habitat) revealed a slower rate of reduction in organochlorine residue burdens.
  • JP LUDWIG, HJ AUMAN, H KURITA, ME LUDWIG, LM CAMPBELL, JP GIESY, DE TILLITT, P JONES, N YAMASHITA, S TANABE, R TATSUKAWA
    JOURNAL OF GREAT LAKES RESEARCH 19 (1) 96 - 108 0380-1330 1993 [Peer-reviewed]
     Scientific journal 
    In the 2 years that followed the 100-year flood incident of September 1986 in the Saginaw River/Bay ecosystem, the reproduction of Caspian terns collapsed and then slowly recovered. Egg viability and fledging rates of hatched chicks were drastically depressed in 1987 and 1988. Eggs from clutches laid later in the year were less viable and chicks hatched from these eggs displayed wasting syndromes and deformities. The post-flood rate of deformities in hatched chicks in 1987-1989 was 163-fold greater than background rates for this population in 1962-1967. Embryonic abnormalities and deformities were found in many embryos recovered from dead eggs. Recently published data on planar toxic chemicals from samples of forage fish, tern eggs, and chicks from water birds nesting in the bay implicate planar dioxin-like PCBs 77 and 126 as the sources of these severe bioeffects. The planar PCB congeners accounted for >98% of TCDD-EQ toxicity in the tern eggs, and several were present at levels near or at the LD95 levels each for chicken eggs. Actual TCDD was about 1% of the TCDD-EQ toxicity. Very rapid buildup rates of PCBs were measured in tern eggs. The calculated toxic potency of PCB recovered from tern eggs was about 15-fold greater than parent aroclor 1242 PCB. Smaller tern species were projected to be much more at risk than the larger Caspian tern due to greater standard metabolic rates. The study supports the view that sediment disturbance and sediment banks of toxic chemicals are major threats to upper trophic level fish-eating species.
  • N YAMASHITA, S TANABE, JP LUDWIG, H KURITA, ME LUDWIG, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 79 (2) 163 - 173 0269-7491 1993 [Peer-reviewed]
     Scientific journal 
    Persistent organochlorine contaminants including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) were determined in eggs with normal and deformed embryos collected in 1988 from different colonies during an epizootiological survey of double-crested cormorants (Phalacrocorax auritus) and Caspian terns (Hydroprogne caspia) from the upper Great Lakes. PCBs and p,p'-DDE were found in the highest concentrations in eggs of both species. The residue pattern of PCB isomers and chlordane compounds suggested that double-crested cormorants have greater metabolic capacity to degrade contaminants than Caspian terns. According to the toxicity evaluation using the 2,3,7,8-TCDD equivalents (TEQs) approach, nonortho coplanar PCBs contributed much more toxicity than PCDDs and PCDFs. Total TEQ of dioxin-like compounds was likely associated with occurrence of live-deformed embryos in double-crested cormorants eggs. The toxic effects of these contaminants were also estimated in Caspian tern eggs, where elevated levels of coplanar PCBs, PCDDs and PCDFs were observed in concordance with increased rate of anomalies in eggs during a breeding season in the Great Lakes.
  • S TANABE, J FALANDYSZ, T HIGAKI, K KANNAN, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 79 (1) 45 - 49 0269-7491 1993 [Peer-reviewed]
     Scientific journal 
    Concentrations of PCBs (polychlorinated biphenyls) and organochlorine insecticides such as DDT, HCHs (hexachlorocyclohexanes), HCB (hexachlorobenzene) and chlordanes were determined in human adipose fat from the provinces of Skierniewice and Gdansk in Poland collected during 1979 and 1990, respectively. The mean levels (mug g-1 lipid weight basis) in Skierniewice and Gdansk were found to be 1.2 +/- 0.44 and 1.5 +/- 1.3 for PCBs, 25 +/- 16 and 15 +/- 13 for DDT, 0.53 +/- 0.17 and 0.25 +/- 0.09 for HCHs, 0.36 +/- 0.22 and 0.26 +/- 0.23 for HCB, and 0.11 +/- 0.08 and 0.07 +/- 0.04 for chlordanes, respectively. Very high concentrations of DDT were detected, with the maximum value as high as 52 mug g-1 lipid weight in Skierniewice and 47 mug g-1 lipid weight in Gdansk PCB residues contained in the human fat from Polish cadavers are comparable to those of the levels reported for industrialized nations. It is appraised from the levels of DDT and PCBs in Poles' fat that the Polish environment is still experiencing both types of contamination, arising from agricultural and industrial activities. Contamination of humans by other organochlorine insecticides was relatively lower.
  • K KANNAN, J FALANDYSZ, N YAMASHITA, S TANABE, R TATASUKAWA
    MARINE POLLUTION BULLETIN 24 (7) 358 - 363 0025-326X 1992/07 [Peer-reviewed]
     Scientific journal 
    Concentrations of PCBs, DDTs, HCHs (BHCs), HCB, aldrin, dieldrin, chlordanes, heptachlor, and heptachlor epoxide were determined in cod-liver oil samples collected from the southern part of the Baltic proper during 1971-1989 for understanding the long-term changes in residue levels and the present status of contamination. There has been a rapid decline in DDT concentrations from 1974 until the present. PCBs, HCB, aldrin, and dieldrin tended to decrease at a very slow rate while HCHs showed a steady state in their time trends. Unlike the pattern observed for other organochlorines, chlordane compounds depicted an upward movement until the early 1980s and then declined. No clear trends could be discerned for heptachlor and heptachlor epoxide. Higher contamination of organochlorines in the present study area might be an indication of the continuous input of these chemicals from eastern Europe and a slower clearance rate in the Baltic ecosystem.
  • A RAMESH, S TANABE, K KANNAN, AN SUBRAMANIAN, PL KUMARAN, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 23 (1) 26 - 36 0090-4341 1992/07 [Peer-reviewed]
     Scientific journal 
    The residue levels of persistent organochlorines, such as HCH (BHC: 1,2,3,4,5,6-hexachlorocyclohexane) isomers, DDT [1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane] compounds, PCBs (polychlorobiphenyls) and HCB (hexachlorobenzene), were measured in wildlife. The wildlife were sampled from terrestrial and aquatic habitats in and around the agricultural watershed of Parangipettai, South India. On the basis of overall concentrations SIGMA-HCH ranked first followed by SIGMA-DDT, SIGMA-PCB and HCB, reflecting the increasing usage of HCH in recent years in India. The residue levels of organochlorines in birds varied according to their feeding habits and showed the following pattern: inland piscivores and scavengers > coastal piscivores > insectivores > omnivores > granivores. High levels of HCH and DDT residues were recorded in Pond heron and Cattle egret which feed in the agricultural fields. Comparison of HCH concentrations in fish and birds in the study area to other locations was made to further understand the dynamics of contaminant accumulation in tropical wildlife. Regarding birds, a wide variation in residue levels could be seen among various countries, with tropical regions registering high levels. In contrast, the variation is not prominent in the case of fish. The residue levels in fish measured in the present study were generally comparable to values reported from other locations. This suggests that the bioavailability of contaminants to the aquatic fauna is less due to the smaller flux and shorter residence time of these chemicals in the tropics.
  • N YAMASHITA, T SHIMADA, S TANABE, H YAMAZAKI, R TATSUKAWA
    MARINE POLLUTION BULLETIN 24 (6) 316 - 321 0025-326X 1992/06 [Peer-reviewed]
     Scientific journal 
    The specific profile of hepatic drug-metabolizing enzymes and isomer-specific residue of PCBs were characterized in the same family of sea gulls such as black-headed gull (Larus ridibundus) and black-tailed gull (Larus crassirostris). The examined enzyme contents and activities were higher in the former species. On the other hand, higher residual level of polychlorinated biphenyls (PCBs) were observed in black-tailed gull. There was no relationship between PCB concentrations and any enzyme activities in both species. A significant correlation between 2,3,7,8-TCDD toxicity equivalents (TEQs) of coplanar PCBs in pectoral muscles and 7-ethoxyresorufin O-deethylase activities in liver microsomes was observed only in black-headed gulls. According to the electrophoretic/immunochemical analysis using antibodies raised against rat P-450 enzymes, it was clear that both birds have the gull P-450 2B protein which is homologous with rat P-450 2B1. However, gull P-450 1A1 and gull P-450 1A2 (these are homologous protein with rat P-450 1A1 and rat P-450 1A2 respectively) were detected only in liver microsomes of black-headed gull. The variation in contents of these P-450 molecular species in these birds are discussed in relation to induction by PCBs.
  • K KANNAN, S TANABE, HT QUYNH, ND HUE, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 22 (4) 367 - 374 0090-4341 1992/05 [Peer-reviewed]
     Scientific journal 
    Concentrations of polychlorobiphenyls (PCBs), hexachlorocyclohexane isomers (HCHs), DDT compounds (DDTs), hexachlorobenzene (HCB), aldrin, dieldrin, heptachlor and heptachlor epoxide were determined in foodstuffs collected from different locations in Vietnam. Elevated levels of PCBs, DDTs, HCHs, and aldrin and dieldrin were found in animal fat, butter, meat, and seafood. Caviar and butter samples imported from the Soviet Union contained considerably higher amounts of PCBs, HCHs and DDTs. The average daily intake of some organochlorines by Vietnamese people were higher than those observed in most of the developed nations. The dietary intake of DDTs was the highest among various chemicals studied. Interestingly, the daily dietary intake of PCBs was comparable to those in developed countries. Fish. shellfish, prawn, and crab were the primary route of DDTs to humans, whereas cereals and vegetables were the predominant sources of PCBs and HCHs.
  • K KANNAN, S TANABE, A RAMESH, A SUBRAMANIAN, R TATSUKAWA
    JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 40 (3) 518 - 524 0021-8561 1992/03 [Peer-reviewed]
     Scientific journal 
    Foodstuffs collected from different regions in India were analyzed for the presence of HCH (BHC), DDT, HCB, aldrin, dieldrin, heptachlor, and PCBs. Significantly high levels of food contamination with HCH, DDT, aldrin, and dieldrin were evident throughout India. Dairy products and livestock meat are the prime sources of human dietary exposure to these chemicals. Concentrations of these organochlorine compounds in a few dairy products were above the maximum residue limits (MRLs) set forth by the FAO/WHO as well as the Ministry of Health of the Indian government. The average daily intakes of HCH and DDT by Indians were estimated to be 115 and 48-mu-g/person, respectively, which were higher than those observed in most of the developed nations. The dietary intakes of aldrin and dieldrin exceeded the acceptable daily intake (ADI) recommended by the FAO/WHO. Food pollution and dietary intakes of PCBs, HCB, and heptachlor were relatively low in India.
  • J FALANDYSZ, N YAMASHITA, S TANABE, R TATSUKAWA
    ZEITSCHRIFT FUR LEBENSMITTEL-UNTERSUCHUNG UND-FORSCHUNG 194 (2) 120 - 123 0044-3026 1992/02 [Peer-reviewed]
     Scientific journal 
    Concentrations of highly toxic coplanar non-ortho (IUPAC Nos. 77, 126 and 169), mono-ortho (IUPAC Nos. 60, 105, 118 and 157), di-ortho (IUPAC Nos. 128, 139 and 170) members and 73 other isomers and congeners of PCBs were determined in canned cod livers Watrobka rybna po Kaukasku produced by a company in Gdansk, Poland in early 1990. Total PCB concentrations ranged over 1.2-2.6-mu-g/g wet mass. Concentrations of ten toxic coplanar PCBs (IUPAC Nos. 77, 126, 169, 60,105, 118, 156, 128, 138, and 170) were found to be in the range of 360 to 690 ng/g wet mass and their TCDD TEQs were 370 to 530 pg/g for aryl hydrocarbon hydroxylase and from 290-430 pg/g for ethoxy-resorufin O-deethylase. Among these toxic congeners IUPAC No. 126, which showed 84% of total TEQ values, imparted most significant toxic threat. Considering these observations, canned cod livers are likely to pose concern to human health since they exceed the tolerance limit of total PCBs (2.0-mu-g/g for edible parts of fishery products) and contain significant residue levels of toxic coplanar PCBs.
  • MS TABUCANON, S WATANABE, C SIRIWONG, R BOONYATUMANOND, S TANABE, H IWATA, R TATSUKAWA, S OHGAKI
    WATER SCIENCE AND TECHNOLOGY 25 (11) 17 - 24 0273-1223 1992 [Peer-reviewed]
     Scientific journal 
    Water and sediment samples collected from the lower Chao Phraya River and a canal along the river during 1988 - 1991 were analyzed to determine the current status of contamination by organochlorine pesticides, such as HCHs, DDTs, aldrin, dieldrin and chlordanes. Aldrin and dieldrin had high frequencies of occurrence in water samples. The medians of concentrations of these pesticides were approximately one order of magnitude larger than total HCHs and total DDTs. Residue levels of these pesticides varied significantly. Relatively higher levels of aldrin were observed in the upstream; in contrast, residue levels of DDTs were higher in urban area. These phenomena seem to relate to the spraying purpose of these pesticides. Decreasing trends in the residue levels of pesticides during monitoring periods, however, were not observed clearly. Residue levels of organochlorines in the sediment samples were in the order of magnitude of PCBs, DDTs, chlordanes and HCHs.
  • J FALANDYSZ, N YAMASHITA, S TANABE, R TATSUKAWA
    INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY 47 (2) 129 - 136 0306-7319 1992 [Peer-reviewed]
     Scientific journal
  • S TANABE, A NISHIMURA, S HANAOKA, T YANAGI, H TAKEOKA, R TATSUKAWA
    MARINE POLLUTION BULLETIN 22 (7) 344 - 351 0025-326X 1991/07 [Peer-reviewed]
     Scientific journal 
    In view of environmental contamination, the function of tidal and thermohaline fronts was examined in the Seto Inland Sea, Japan. These fronts have a potency to elevate the concentrations of persistent organochlorines not only in surface water but also in organisms and sediments. The enrichment of organochlorines during the formation of the front was more pronounced for lipophilic contaminants with higher particle affinity, probably due to the amassment of oily substances and various particles through the surface convergence. The coastal fronts may play a significant role in determining the fate of persistent contaminants in the marine environment.
  • H TAKEOKA, A RAMESH, H IWATA, S TANABE, AN SUBRAMANIAN, D MOHAN, A MAGENDRAN, R TATSUKAWA
    MARINE POLLUTION BULLETIN 22 (6) 290 - 297 0025-326X 1991/06 [Peer-reviewed]
     Scientific journal 
    The residue levels of the insecticide HCH in Vellar estuary, Tamil Nadu, South India were surveyed along with the physical structure of estuary and its hydrokinetic parameters to assess the transport of contaminants in tropical coastal areas. From the flux model it was estimated that most of the HCH applied to the catchment area of Vellar river is removed to the air and only a small part of it was drained to the sea. Compared to the present situation, the flux of HCH to the sea seems to be much larger in the past when the river structure was different from the present. This implies that at present the localized contamination of HCH in the sea is reducing: instead more rapid contamination is advancing on global terms due to the 'long-range atmospheric transport' of residues from the 'point-source' areas.
  • A RAMESH, S TANABE, H MURASE, AN SUBRAMANIAN, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 74 (4) 293 - 307 0269-7491 1991 [Peer-reviewed]
     Scientific journal 
    Paddy soil and sediment samples collected from the Vellar River watershed, Tamil Nadu state, South India from December, 1987 to January, 1989 were analysed to understand the comprehensive behaviour of organochlorine insecticides (HCH and DDT) in the tropical environment. HCH (BHC) showed higher levels in soil during wet season, reflecting the application of technical HCH largely during the flowering season of rice. On the other hand, DDT residues were low and did not show a significant seasonal trend in soil or sediment, indicating small quantities of DDT utilized at present for agricultural purposes in India. When compared to soil, the residue levels in sediments are low and the seasonal variation is less pronounced. This indicates that in tropical watersheds, the relative flux of residues into the aquatic environment is smaller than the amount volatilized to the atmosphere.
  • S TANABE, K KANNAN, MS TABUCANON, C SIRIWONG, Y AMBE, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 72 (3) 191 - 203 0269-7491 1991 [Peer-reviewed]
     Scientific journal 
    Raw foodstuffs collected from Bangkok, Thailand, were analysed for the presence of PCBs, DDTs, HCHs (BHCs), HCB, aldrin, dieldrin, heptachlor and heptachlor epoxide. Residues of PCBs and organochlorine pesticides were detected in all the samples analysed. Concentrations of PCBs did not reach the tolerance limit set forth by the US Food and Drug Administration (FDA). The concentrations of SIGMA-HCH were higher than those of SIGMA-DDT in all the farm products while the levels of SIGMA-DDT were greater in fishes including fish flakes and fishmeal. Meat samples recorded higher concentrations of SIGMA-DDT and dieldrin than SIGMA-HCH. Comparing the levels of organochlorines in foodstuffs from Bangkok, considerable levels of aldrin and dieldrin indicate the need for concern from the food safety point of view because of their much higher toxicity than DDT and other organochlorines. However, the levels did not exceed the Maximum Residue Limit (MRL) recommended by FAO/WHO. Food contamination by HCB, heptachlor and heptachlor epoxide is comparatively lower.
  • S TANABE, A RAMESH, D SAKASHITA, H IWATA, R TATSUKAWA, D MOHAN, AN SUBRAMANIAN
    INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY 45 (1) 45 - 53 0306-7319 1991 [Peer-reviewed]
     Scientific journal
  • A RAMESH, S TANABE, AN SUBRAMANIAN, D MOHAN, VK VENUGOPALAN, R TATSUKAWA
    MARINE POLLUTION BULLETIN 21 (12) 587 - 590 0025-326X 1990/12 [Peer-reviewed]
     Scientific journal 
    Green mussels (Perna viridis) collected from nine locations along the South Indian coast were used as bioindicator to assess the organochlorine contamination (HCHs, DDTs, and PCBs) in the coastal environment of South India. Concentrations of SIGMA-HCH and SIGMA-DDT were found to be similar, ranging from 3 to 39 ng g-1 on wet wt basis. On the other hand, PCB levels were apparently lower, varying from < 1.0 to 7.1 ng g-1 wet wt. The residue pattern of organochlorines in mussels are principally similar to those in Indian human samples, reported earlier. The coastal marine pollution by HCH in India ranks among the highly contaminated areas in the world.
  • BG LOGANATHAN, S TANABE, H TANAKA, S WATANABE, N MIYAZAKI, M AMANO, R TATSUKAWA
    MARINE POLLUTION BULLETIN 21 (9) 435 - 439 0025-326X 1990/09 [Peer-reviewed]
     Scientific journal
  • S TANABE, F GONDAIRA, A SUBRAMANIAN, A RAMESH, D MOHAN, P KUMARAN, VK VENUGOPALAN, R TATSUKAWA
    JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 38 (3) 899 - 903 0021-8561 1990/03 [Peer-reviewed]
     Scientific journal
  • A RAMESH, S TANABE, H IWATA, R TATSUKAWA, AN SUBRAMANIAN, D MOHAN, VK VENUGOPALAN
    ENVIRONMENTAL POLLUTION 67 (4) 289 - 304 0269-7491 1990 [Peer-reviewed]
     Scientific journal
  • N KANNAN, S TANABE, M ONO, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 18 (6) 850 - 857 0090-4341 1989/11 [Peer-reviewed]
     Scientific journal
  • S TANABE, N KANNAN, M FUKUSHIMA, T OKAMOTO, T WAKIMOTO, R TATSUKAWA
    MARINE POLLUTION BULLETIN 20 (7) 344 - 352 0025-326X 1989/07 [Peer-reviewed]
     Scientific journal
  • DJH PHILLIPS, S TANABE
    MARINE POLLUTION BULLETIN 20 (7) 297 - 303 0025-326X 1989/07 [Peer-reviewed]
     Scientific journal
  • BG LOGANATHAN, S TANABE, R TATSUKAWA, K OGAWA, M GOTO
    NIPPON SUISAN GAKKAISHI 55 (5) 769 - 774 0021-5392 1989/05 [Peer-reviewed]
     Scientific journal
  • BG LOGANATHAN, S TANABE, M GOTO, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 62 (2-3) 237 - 251 0269-7491 1989 [Peer-reviewed]
     Scientific journal
  • N KANNAN, S TANABE, T OKAMOTO, R TATSUKAWA, DJH PHILLIPS
    ENVIRONMENTAL POLLUTION 62 (2-3) 223 - 235 0269-7491 1989 [Peer-reviewed]
     Scientific journal
  • A RAMESH, S TANABE, R TATSUKAWA, AN SUBRAMANIAN, S PALANICHAMY, D MOHAN, VK VENUGOPALAN
    ENVIRONMENTAL POLLUTION 62 (2-3) 213 - 222 0269-7491 1989 [Peer-reviewed]
     Scientific journal
  • S TANABE, N KANNAN, T WAKIMOTO, R TATSUKAWA, T OKAMOTO, Y MASUDA
    TOXICOLOGICAL AND ENVIRONMENTAL CHEMISTRY 24 (4) 215 - 231 0277-2248 1989 [Peer-reviewed]
     Scientific journal
  • S WATANABE, T SHIMADA, S NAKAMURA, N NISHIYAMA, N YAMASHITA, S TANABE, R TATSUKAWA
    MARINE ENVIRONMENTAL RESEARCH 27 (1) 51 - 65 0141-1136 1989 [Peer-reviewed]
     Scientific journal
  • N KANNAN, S TANABE, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 56 (1) 65 - 76 0269-7491 1989 [Peer-reviewed]
     Scientific journal
  • S TANABE, N KANNAN, M ONO, R TATSUKAWA
    CHEMOSPHERE 18 (1-6) 485 - 490 0045-6535 1989 [Peer-reviewed]
     Scientific journal
  • N KANNAN, S TANABE, R TATSUKAWA
    BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 41 (2) 267 - 276 0007-4861 1988/08 [Peer-reviewed]
     Scientific journal
  • A SUBRAMANIAN, S TANABE, R TATSUKAWA
    MARINE POLLUTION BULLETIN 19 (6) 284 - 287 0025-326X 1988/06 [Peer-reviewed]
     Scientific journal
  • S TANABE, S WATANABE, H KAN, R TATSUKAWA
    MARINE MAMMAL SCIENCE 4 (2) 103 - 124 0824-0469 1988/04 [Peer-reviewed]
     Scientific journal
  • A SUBRAMANIAN, S TANABE, R TATSUKAWA
    MARINE ENVIRONMENTAL RESEARCH 25 (3) 161 - 174 0141-1136 1988 [Peer-reviewed]
     Scientific journal
  • Subramanian, A. N, Tanabe, S, Tatsukawa, R
    Researches in Organic Geochemistry 6 51 - 54 1988 [Peer-reviewed]
  • N KANNAN, S TANABE, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL HEALTH 43 (1) 11 - 14 0003-9896 1988/01 [Peer-reviewed]
     Scientific journal
  • A SUBRAMANIAN, S TANABE, R TATSUKAWA, S SAITO, N MIYAZAKI
    MARINE POLLUTION BULLETIN 18 (12) 643 - 646 0025-326X 1987/12 [Peer-reviewed]
     Scientific journal
  • S TANABE, BG LOGANATHAN, A SUBRAMANIAN, R TATSUKAWA
    MARINE POLLUTION BULLETIN 18 (10) 561 - 563 0025-326X 1987/10 [Peer-reviewed]
     Scientific journal
  • N KANNAN, S TANABE, T WAKIMOTO, R TATSUKAWA
    JOURNAL OF THE ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS 70 (3) 451 - 454 0004-5756 1987/05 [Peer-reviewed]
     Scientific journal
  • A stranding of Mesoplodon stejnegeri in the Maizuru Bay, Sea of Japan.
    Miyazaki, N, Nakamura, I, Tanabe, S, Tatsukawa, R
    The Scientific Reports of the Whales Research Institute (38) 91 - 105 1987/03 [Peer-reviewed]
  • Age and size trends and male-female differences of PCBs and DDE in dalli-type Dall's porpoises, Phocoenoides dalli of northwestern North Pacific.
    Subramanian, A. N, Tanabe, S, Tatsukawa, R
    Proceedings of the National Institute of Polar Research Symposiumu on Polar Biology (1) 205 - 216 1987 [Peer-reviewed]
  • S TANABE, N KANNAN, A SUBRAMANIAN, S WATANABE, M ONO, R TATSUKAWA
    CHEMOSPHERE 16 (8-9) 1965 - 1970 0045-6535 1987 [Peer-reviewed]
     Scientific journal
  • N KANNAN, S TANABE, T WAKIMOTO, R TATSUKAWA
    CHEMOSPHERE 16 (8-9) 1631 - 1634 0045-6535 1987 [Peer-reviewed]
     Scientific journal
  • S TANABE, N KANNAN, A SUBRAMANIAN, S WATANABE, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 47 (2) 147 - 163 0269-7491 1987 [Peer-reviewed]
     Scientific journal
  • S TANABE, R TATSUKAWA, DJH PHILLIPS
    ENVIRONMENTAL POLLUTION 47 (1) 41 - 62 0269-7491 1987 [Peer-reviewed]
     Scientific journal
  • S TANABE, N KANNAN, T WAKIMOTO, R TATSUKAWA
    INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY 29 (3) 199 - 213 0306-7319 1987 [Peer-reviewed]
     Scientific journal
  • AN SUBRAMANIAN, S TANABE, H TANAKA, H HIDAKA, R TATSUKAWA
    ENVIRONMENTAL POLLUTION 43 (1) 39 - 46 0269-7491 1987 [Peer-reviewed]
     Scientific journal
  • Organochlorine residues in Dall's and True's porpoises collected from northwestern Pacific and adjacent waters.
    Subramanian, A. N, Tanabe, S, Fujise, Y, Tatsukawa, R
    Memoirs of National Institute of Polar Research (44) 167 - 173 1986/12 [Peer-reviewed]
  • Variations of organochlorine residues with age and sex in Antarctic minke whale.
    Tanabe, S, Miura, S, Tatsukawa, R
    Memoirs of National Institute of Polar Research (44) 174 - 181 1986/12 [Peer-reviewed]
  • Bioaccumulation and metabolism of PCBs and DDE in short-tailed shearwater Puffinus tenuirostris during its transequatorial migration and in the wintering and breeding grounds.
    Tanaka, H, Ogi, H, Tanabe, S, Tatsukawa, R, Oka, N
    Memoirs of National Institute of Polar Research (40) 434 - 442 1986/02 [Peer-reviewed]
  • Distribution and transfer of organochlorines in Adelie penguins (Pygoscelis adeliae).
    Subramanian, A. N, Tanabe, S, Hidaka, H, Tatsukawa, R
    Memoirs of National Institute of Polar Research (40) 423 - 433 1986/02 [Peer-reviewed]
  • S TANABE, A SUBRAMANIAN, H HIDAKA, R TATSUKAWA
    CHEMOSPHERE 15 (3) 343 - 351 0045-6535 1986 [Peer-reviewed]
     Scientific journal
  • A SUBRAMANIAN, S TANABE, H HIDAKA, R TATSUKAWA
    ENVIRONMENTAL POLLUTION SERIES A-ECOLOGICAL AND BIOLOGICAL 40 (2) 173 - 189 0143-1471 1986 [Peer-reviewed]
     Scientific journal
  • M KAWANO, S TANABE, T INOUE, R TATSUKAWA
    TRANSACTIONS OF THE TOKYO UNIVERSITY OF FISHERIES-TOKYO SUISAN DAIGAKU TOKUBETSU KENKYU HOKOKU (6) 59 - 66 0388-0966 1985 [Peer-reviewed]
     Scientific journal
  • Fate of DDTs, PCBs and chlordane compounds in the Antarctic marine ecosystem.
    Hidaka, H, Tanabe, S, Kawano, M, Tatsukawa, R
    Memoirs of National Institute of Polar Research (32) 151 - 161 1984/08 [Peer-reviewed]
  • Bioaccumulation of DDTs and PCBs in the southern minke whale (Balaenoptera acutrostrata).
    Tanabe, S, Mori, T, Tatsukawa, R
    Memoirs of National Institute of Polar Research (32) 140 - 150 1984/08 [Peer-reviewed]
  • S TANABE, H TANAKA, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 13 (6) 731 - 738 0090-4341 1984 [Peer-reviewed]
     Scientific journal
  • Shinsuke Tanabe, Ryo Tatsukawa
    Journal of the Oceanographical Society of Japan 39 (2) 53 - 62 0029-8131 1983/04 [Peer-reviewed]
     Scientific journal 
    The vertical transport of PCBs and chlorinated hydrocarbon pesticides such as DDT compounds and HCH (BHC) isomers in the deep sea are discussed on basis of their vertical profiles and the proportion of their adsorbed and dissolved fractions in surface water surveyed in the Western Pacific, Eastern Indian and Antarctic Oceans. All chlorinated hydrocarbons determined were detected with measurable concentrations throughout the water column, even at depths of several thousand meters. The vertical distributions of PCBs and DDT compounds were found to show small variations in concentration throughout the water column, whereas HCH isomer concentrations decreased systematically with depth. A large portion of DDT compounds in surface water was adsorbed on suspended solids, while most of the HCH isomers were present in the filtered water. The proportion of PCBs adsorbed on suspended solids was smaller than the proportion of DDT compounds, but was much greater than that of HCH isomers. These observations suggest that HCH isomers have been slowly scavenged from the surface to the deeper layers in the water column, while PCBs and DDT compounds have been rapidly and abundantly transported downward by sinking particles. The percentages of chlorinated hydrocarbons adsorbed on suspended solids in surface water increased towards the high latitude locations, and the percentage seemed to be proportional to the concentration of suspended solids in the surface water. This implies that the residence time of chlorinated hydrocarbons in the water column will differ significantly among oceans that differ in primary productivity. According to our estimation based on the data presented in this study, the residence time of σHCH in the euphotic zone, the top 100 m of the water column, is more than 2 years, whereas those of PCBs and σDDT are less than 1 year. The longest residence time, of from 5 to 10 years, was obtained for σHCH in oligotrophic water of the western North Pacific. The shortest value, only 11 to 19 days, was estimated for σDDT in the Antarctic Ocean. © 1983 Oceanographical Society of Japan.
  • S SAEKI, S TANABE, Y NAKAGAWA, R TATSUKAWA
    JOURNAL OF THE AGRICULTURAL CHEMICAL SOCIETY OF JAPAN 57 (12) 1219 - 1226 1983 [Peer-reviewed]
     Scientific journal
  • BR SUBRAMANIAN, S TANABE, H HIDAKA, R TATSUKAWA
    ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 12 (6) 621 - 626 0090-4341 1983 [Peer-reviewed]
     Scientific journal
  • K MARUYAMA, M SAHRUL, S TANABE, R TATSUKAWA
    ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 7 (5) 514 - 520 0147-6513 1983 [Peer-reviewed]
     Scientific journal
  • Chlorinated hydrocarbons in the Southern Ocean.
    Tanabe, S, Tatsukawa, R
    Memoirs of National Institute of Polar Research (27) 64 - 76 1983 [Peer-reviewed]
  • S TANABE, T MORI, R TATSUKAWA, N MIYAZAKI
    CHEMOSPHERE 12 (9-10) 1269 - 1275 0045-6535 1983 [Peer-reviewed]
     Scientific journal
  • H HIDAKA, S TANABE, R TATSUKAWA
    AGRICULTURAL AND BIOLOGICAL CHEMISTRY 47 (9) 2009 - 2017 0002-1369 1983 [Peer-reviewed]
     Scientific journal
  • S TANABE, H HIDAKA, R TATSUKAWA
    CHEMOSPHERE 12 (2) 277 - 288 0045-6535 1983 [Peer-reviewed]
     Scientific journal
  • Shinsuke Tanabe, Ryo Tatsukawa, Masahide Kawano, Hideo Hidaka
    Journal of the Oceanographical Society of Japan 38 (3) 137 - 148 0029-8131 1982/07 [Peer-reviewed]
     Scientific journal 
    Concentrations of chlorinated hydrocarbons such as HCH isomers and DDT compounds were determined in air and surface water samples taken from the Western Pacific, Eastern Indian and Antarctic Oceans. The most interesting finding was their presence in measurable concentrations in the Antarctic Ocean. Chlorinated hydrocarbon pesticides are widely distributed in the open ocean environment over both the northern and southern hemispheres, and some characteristic distribution patterns of pesticide species in different oceanic regions were observed both in air and water samples. HCH residues found in the northern hemisphere were much higher in concentration than those in the southern hemisphere. On the other hand, higher concentrations of DDT residues were found in the tropical regions, but their levels were not so different between both the northern and southern hemispheres. HCH isomers found in the northern hemisphere had the following order of concentrations:α-HCH> γ HCH> β-HCH, while in the southern hemisphere γ-HCH was apparently dominant. DDT compound compositions were rather uniform in all the oceans surveyed, and more than 50% was p,p′-DDT. These facts can be explained by the world wide situation regarding pesticide use and the physicochemical properties of the pesticides such as their vapor pressures and water solubilities. In addition, the meridional circulation of the atmosphere, particularly the mass flows of the Hadley and Ferrel cells in the troposphere, also contributes to the atmospheric transport and global distribution of these pesticides. © 1982 Oceanographical Society of Japan.
  • Chlorinated hydrocarbons in the Antarctic, western Pacific and eastern Indian Oceans.
    Tanabe, S, Kawano, M, Tatsukawa, R
    Transactions of the Tokyo University of Fisheries (5) 97 - 109 0388-0966 1982 [Peer-reviewed]
  • S TANABE, R TATSUKAWA, K MARUYAMA, N MIYAZAKI
    AGRICULTURAL AND BIOLOGICAL CHEMISTRY 46 (5) 1249 - 1254 0002-1369 1982 [Peer-reviewed]
     Scientific journal
  • S TANABE, K MARUYAMA, R TATSUKAWA
    AGRICULTURAL AND BIOLOGICAL CHEMISTRY 46 (4) 891 - 898 0002-1369 1982 [Peer-reviewed]
     Scientific journal
  • S TANABE, R TATSUKAWA, H TANAKA, K MARUYAMA, N MIYAZAKI, T FUJIYAMA
    AGRICULTURAL AND BIOLOGICAL CHEMISTRY 45 (11) 2569 - 2578 0002-1369 1981 [Peer-reviewed]
     Scientific journal
  • S TANABE, Y NAKAGAWA, R TATSUKAWA
    AGRICULTURAL AND BIOLOGICAL CHEMISTRY 45 (3) 717 - 726 0002-1369 1981 [Peer-reviewed]
     Scientific journal
  • 沿岸域および河口域における人工有機化合物の動態
    田辺信介, 立川 涼
    沿岸海洋研究ノート 19 (1) 9 - 19 1981 [Peer-reviewed]
  • Tanabe, S, Tatsukawa, R
    Journal of the Oceanographical Society of Japan 36 (4) 217 - 226 1980/10 [Peer-reviewed]
  • 田辺信介, 田中博之, 立川 涼, 中村 泉
    日本水産学会誌 46 (6) 763 - 769 1980 [Peer-reviewed]

Books etc

  • 坂田 昌弘, 磯部 友彦, 梶井 克純, 加藤 義久, 高橋 嘉夫, 田辺 信介, 藤江 幸一, 益永 茂樹 (Joint work)
    講談社 2015/10 4061568051 272
  • 坂田 昌弘, 磯部 友彦, 梶井 克純, 加藤 義久, 高橋 嘉夫, 田辺 信介, 藤江 幸一, 益永 茂樹 
    講談社 2015 9784061568051
  • Arsenic in Geosphere and Human Diseases : Methylation of inorganic arsenic and genetic polymorphisms in arsenic (+III oxidation state) methyltransferase in a Vietnamese population
    CRC Press 2010
  • Interdisciplinary Studies on Environmental Chemistry vol. 3, Biological Responses to Contaminants: from Molecular to Community Level : Interindividual variation in arsenic metabolism in a Vietnamese population: association with 17 single nucleotide pol・・・
    TERRAPUB 2010 
    Interdisciplinary Studies on Environmental Chemistry vol. 3, Biological Responses to Contaminants: from Molecular to Community Level : Interindividual variation in arsenic metabolism in a Vietnamese population: association with 17 single nucleotide polymorphisms in AS3MT
  • Interdisciplinary Studies on Environmental Chemistry Vol. 4, Environmental Specimen Bank: Exploring Possibility of Setting-up ESBs in Developing Countries : Development of an in vitro reporter gene assay for screening the ecdysone receptor agonists in ・・・
    TERRAPUB 2010 
    Interdisciplinary Studies on Environmental Chemistry Vol. 4, Environmental Specimen Bank: Exploring Possibility of Setting-up ESBs in Developing Countries : Development of an in vitro reporter gene assay for screening the ecdysone receptor agonists in mysid crustacean
  • Interdisciplinary Studies on Environmental Chemistry Vol. 4, Environmental Specimen Bank: Exploring Possibility of Setting-up ESBs in Developing Countries : Molecular characterization of peroxisome proliferator-activated receptor isoforms from the baik・・・
    TERRAPUB 2010 
    Interdisciplinary Studies on Environmental Chemistry Vol. 4, Environmental Specimen Bank: Exploring Possibility of Setting-up ESBs in Developing Countries : Molecular characterization of peroxisome proliferator-activated receptor isoforms from the baikal seal (Pusa sibirica)
  • Arsenic in Geosphere and Human Diseases : Methylation of inorganic arsenic and genetic polymorphisms in arsenic (+III oxidation state) methyltransferase in a Vietnamese population
    CRC Press 2010
  • Interdisciplinary Studies on Environmental Chemistry vol. 3, Biological Responses to Contaminants: from Molecular to Community Level : Interindividual variation in arsenic metabolism in a Vietnamese population: association with 17 single nucleotide pol・・・
    TERRAPUB 2010 
    Interdisciplinary Studies on Environmental Chemistry vol. 3, Biological Responses to Contaminants: from Molecular to Community Level : Interindividual variation in arsenic metabolism in a Vietnamese population: association with 17 single nucleotide polymorphisms in AS3MT
  • Interdisciplinary Studies on Environmental Chemistry Vol. 4, Environmental Specimen Bank: Exploring Possibility of Setting-up ESBs in Developing Countries : Development of an in vitro reporter gene assay for screening the ecdysone receptor agonists in ・・・
    TERRAPUB 2010 
    Interdisciplinary Studies on Environmental Chemistry Vol. 4, Environmental Specimen Bank: Exploring Possibility of Setting-up ESBs in Developing Countries : Development of an in vitro reporter gene assay for screening the ecdysone receptor agonists in mysid crustacean
  • Interdisciplinary Studies on Environmental Chemistry Vol. 4, Environmental Specimen Bank: Exploring Possibility of Setting-up ESBs in Developing Countries : Molecular characterization of peroxisome proliferator-activated receptor isoforms from the baik・・・
    TERRAPUB 2010 
    Interdisciplinary Studies on Environmental Chemistry Vol. 4, Environmental Specimen Bank: Exploring Possibility of Setting-up ESBs in Developing Countries : Molecular characterization of peroxisome proliferator-activated receptor isoforms from the baikal seal (Pusa sibirica)
  • 田辺 信介 
    [愛媛大学グローバルCOEプログラム「化学物質の環境科学教育研究拠点」 ] 2009
  • Murakami Yasunori, Nakayama Kei, Kitamura Shin-ichi, Iwata Hisato, 田辺 信介 
    TERRAPUB 2008 9784887041455
  • 西田 周平, 田辺 信介, 太田 秀, 西川 淳 
    西田周平 2007
  • International, Symposium Pioneering, Studies of Young, Scientists on Chemical Pollution, Environmental Changes, 田辺 信介 
    Universal Academy Press 2007 9784946443411
  • 田辺 信介, Subramanian Annamalai (Joint work)
    Kyoto University Press, Trans Pacific Press 2006/04 487698672X 190
  • 寺崎 誠, 川村 宏, 道田 豊, 乙部 弘隆, 福代 康夫, 古谷 研, 児玉 正昭, 宮崎 信之, 田辺 信介, 新井 崇臣 
    寺崎誠 2006
  • Mankind and the Oceans
    United Nations University Press, Tokyo, Japan 2005
  • Mankind and the Oceans
    United Nations University Press, Tokyo, Japan 2005
  • 有機塩素化合物の汚染, 三陸の海と生物
    サイエンティスト社 2005
  • Mankind and the Oceans
    United Nations University Press, Tokyo, Japan 2005
  • Mankind and the Oceans
    United Nations University Press, Tokyo, Japan 2005
  • Contamination and toxic effects of persistent organic pollutants in wildlife and humans in Asia. Ecological Destruction, Health, and Development
    Kyoto University Press 2004
  • 水産学シリーズ140
    恒星社厚生閣刊 2004
  • 水産学シリーズ140
    恒星社厚生閣刊 2004
  • 水産海洋ハンドブック
    生物研究者 2004
  • Contamination and toxic effects of persistent organic pollutants in wildlife and humans in Asia. Ecological Destruction, Health, and Development
    Kyoto University Press 2004
  • 竹内 一郎, 田辺 信介, 日野 明徳 
    恒星社厚生閣 2004 4769910053
  • 理科年表環境編
    丸善 2003
  • Persistent organochlorine residues and their bioaccumulation profiles in resident and migratory birds from North Vietnam.
    Joint Research on Environmental Science and Technology for the Earth: Annual Report of FY 2001 2003
  • Persistent ocean contaminants and marine mammals: a retrospective overview.
    Toxicology of Marine Mammals 2003
  • 人工有機化合物
    地球温暖化と日本―自然・人への影響予測 2003
  • 生物蓄積性内分泌攪乱物質による野生高等動物の汚染
    環境ホルモンの最新動向と測定・試験・器機開発,地球環境シリーズ 2003
  • Persistent organochlorine residues and their bioaccumulation profiles in resident and migratory birds from North Vietnam.
    Joint Research on Environmental Science and Technology for the Earth: Annual Report of FY 2001 2003
  • Persistent ocean contaminants and marine mammals: a retrospective overview.
    Toxicology of Marine Mammals 2003
  • 松井 三郎, 森 千里, 吉原 新一, 森沢 真輔, 田辺 信介, 井口 泰泉, 有薗 幸司 (Joint work)
    有斐閣 2002/11 4641280789 252
  • Butyltin contamination in mussels from Vietnam and other Asian developing countries.
    Joint Research on Environmental Science and Technology for the Earth: Annual Report of FY 2000 2002
  • 海洋の有機塩素化合物汚染,地球環境ハンドブック第2版,不破敬一郎・森田昌敏編著
    朝倉書店 2002
  • 地球規模で広がる環境ホルモンの汚染と野生生物への影響,環境ホルモンの最前線
    有斐閣 2002
  • 鯨類調査の新技術―有機塩素化合物や重金属類をトレーサーとした鯨類の生態解明の試み,鯨類資源研究の最前線―鯨類資源の持続的利用は可能か,加藤秀弘・大隅清治編
    生物研究社 2002
  • 内分泌攪乱物質による海棲哺乳動物の汚染,紛争の海―水産資源管理の人類学,秋道智彌・岸上伸啓編
    人文書院 2002
  • Butyltin contamination in mussels from Vietnam and other Asian developing countries.
    Joint Research on Environmental Science and Technology for the Earth: Annual Report of FY 2000 2002
  • Persistent organic pollutants in the seas of Asian developing regions. Joint Research on Environmental Science and Technology for the Earth: Annual Report of FY 1999, Fujita,M. and Viet,P.H. (Eds.)
    Osaka University , Japan, 2001
  • Persistent organic pollutants in the seas of Asian developing regions.
    Joint Research on Environmental Science and Technology for the Earth : Annual Report of FY 1999 2001
  • 有機スズ化合物の生物蓄積と環境動態,内分泌攪乱物質研究の最前線,季刊化学総説 No.50,日本化学会編
    学会出版センター 2001
  • 有機塩素化合物のグローバルな動態,内分泌攪乱物質研究の最前線,季刊化学総説 No.50,日本化学会編
    学会出版センター 2001
  • 途上国の環境問題
    国際保健医療学,杏林書院 2001
  • Persistent organic pollutants in the seas of Asian developing regions. Joint Research on Environmental Science and Technology for the Earth: Annual Report of FY 1999, Fujita,M. and Viet,P.H. (Eds.)
    Osaka University , Japan, 2001
  • Persistent organic pollutants in the seas of Asian developing regions.
    Joint Research on Environmental Science and Technology for the Earth : Annual Report of FY 1999 2001
  • 川口 弘一, 田辺 信介, 西田 周平, 西川 淳 
    川口弘一 2001
  • Contamination of the ecosystems of Lake Baikal by persistent organochlorines.
    Elsevier, Lake Baikal 2000
  • Asian developing regions : persistent organic pollutants in the seas
    Seas at the Millennium : An Environmental Evaluation, Pergamon 2000
  • 海産哺乳動物
    水産環境における内分泌撹乱物質, 恒星社厚生閣 2000
  • 宇和海の化学環境
    「海は命」宇和島湾浅海養殖漁場環境調査報告書(昭和59年度~平成10年度),xviii. 2000
  • 生態系への影響マネジメント(ソースコントロール)について
    環境ホルモンの総合的リスク管理-環境ホルモンの今後を探る-環境新聞社 2000
  • 第2章 生物におよぼす影響,第3章 環境ホルモンがあらわれてきた歴史
    環境ホルモン汚染,ポプラ社 2000
  • Contamination of the ecosystems of Lake Baikal by persistent organochlorines.
    Elsevier, Lake Baikal 2000
  • Asian developing regions : persistent organic pollutants in the seas
    Seas at the Millennium : An Environmental Evaluation, Pergamon 2000
  • 志村 岳, 田辺 信介, 井口 泰泉, 押尾 茂 (Joint work)
    講談社 1999/02 4062563258 315
  • 内分泌かく乱物質による環境汚染と生物への影響
    家の光協会農林水産業と環境ホルモン,家の光協会 1999
  • 環境ホルモンの野生生物への影響はどうなっているのか どうしたらいいの環境ホルモン
    読売新聞社どうしたらいいの環境ホルモン,読売新聞社 1999
  • 海洋汚染の進行
    図解ひと目でわかる「環境ホルモン」ハンドブック」,講談社 1999
  • 田辺 信介 (Single work)
    岩波書店 1998/06 4000033964 54
  • Distribution, transport, and transformation of organochlorine compounds
    SETAC Press, Ecotoxicological Risk Assessment of Chlorinated Organic Chemicals 1998
  • 環境ホルモンによる野生生物の汚染
    ダイオキシンと環境ホルモン,科学のとびら33,東京化学同人 1998
  • PCB,漁場環境の保全
    沿岸の環境圏 フジ・テクノシステム 1998
  • 海棲ほ乳類の化学汚染
    よくわかる環境ホルモン学 環境新聞社 1998
  • 環境ホルモン-何が問題なのか-
    岩波ブックレットNo456 岩波書店 1998
  • Distribution, transport, and transformation of organochlorine compounds
    SETAC Press, Ecotoxicological Risk Assessment of Chlorinated Organic Chemicals 1998
  • Colborn Theo, 養老 孟司, 高杉 暹, 田辺 信介, 井口 泰泉, 堀口 敏宏, 森 千里, 香山 不二雄, 椎葉 茂樹, 戸高 恵美子 
    環境新聞社 1998 4905622425
  • Organochlorine pesticides and polychlorinated biphenyls in foodstuffs from Asian and Oceanic countries
    Reviews of Environmental Contamination and Toxicology 1997
  • Organochlorine pesticides and polychlorinated biphenyls in foodstuffs from Asian and Oceanic countries
    Reviews of Environmental Contamination and Toxicology 1997
  • 海洋汚染とクジラ・イルカ類
    日本動物大百科, 哺乳類, 平凡社 1996
  • Highly toxic non-ortho-chlorine substituted coplanar PCBs in white-tailed sea eagles (Haliaeetus albicilla) from Poland.
    Pica Press,Raptor Conservation Today 1994
  • Fate of persistent organochlorines in the marine environment.
    CRC Press,Contaminants in the Environment 1994
  • 有害物質による汚染
    海洋環境問題の変還と課題-海洋環境を考える、恒星社厚生閣 1994
  • 有機塩素化合物によるバイカル湖の汚染
    バイカル湖、東京大学出版会 1994
  • 海洋の有機塩素化合物汚染
    地球環境ハンドブック、朝倉書店 1994
  • Highly toxic non-ortho-chlorine substituted coplanar PCBs in white-tailed sea eagles (Haliaeetus albicilla) from Poland.
    Pica Press,Raptor Conservation Today 1994
  • Fate of persistent organochlorines in the marine environment.
    CRC Press,Contaminants in the Environment 1994
  • Chemical modernization and vulnerability of cetaceans ; increasing toxic threat of organochlorine contaminants.
    Elsevier Applied Science,Persistent Pollutants in Marine Ecosystems 1992
  • Chemical modernization and vulnerability of cetaceans ; increasing toxic threat of organochlorine contaminants.
    Elsevier Applied Science,Persistent Pollutants in Marine Ecosystems 1992
  • Presistent organochlorines in marine mammals.
    Elsevier Applied Science,Organic Contaminants in the Environment 1991
  • Presistent organochlorines in marine mammals.
    Elsevier Applied Science,Organic Contaminants in the Environment 1991
  • Distribution, behavior and load of PCBs in the ocean.
    CRC Press,PCBs and the Environment 1986
  • Distribution, behavior and load of PCBs in the ocean.
    CRC Press,PCBs and the Environment 1986
  • 田辺 信介, Subramanian Annamalai 
    Kyoto University Press, Trans Pacific Press 1920901116

Works

  • 沿岸環境科学研究拠点
    2002 -2006
  • Center of Excellence for Coastal Marine Environmental Research
    2002 -2006
  • 内分泌撹乱化学物質問題に関する日韓共同研究
    2001 -2005
  • Japan-Korea Joint Research on Endocrine Disrupting Chemicals
    2001 -2005
  • 南半球産及び北西太平洋産ミンククジラの有機塩化合物蓄積に関する研究
    2000 -2005
  • Accumulation of Organochlorines in Minke Whales from Antarctic and Western North Pacific Oceans
    2000 -2005
  • 内分泌撹乱化学物質問題に関する日英共同研究
    2000 -2004
  • UK-Japan Joint Research on Endocrine Disrupting Chemicals
    2000 -2004
  • 内分泌撹乱物質の小児、成人等の汚染実態および暴露に関する調査研究
    1999 -2004
  • Research on Environmental Health Human Exposure by Endocrine Disrupters in Japan
    1999 -2004
  • 希少鳥類の生存と回復に関する研究
    2001 -2003
  • 野生生物における内分泌撹乱物質の汚染とそのリスク評価
    2001 -2003
  • Survival and Recovery of Scare Birds
    2001 -2003
  • Contamination and Risk Assessment of Endocrine Disrupters in Wildlife
    2001 -2003
  • 生物蓄積性内分泌撹乱かく乱物質による野生高等動物の汚染と影響
    2000 -2003
  • Contamination and Toxic Effects of Bioaccumulative Endocrine Disrupters in Wildlife
    2000 -2003
  • カスピカイアザラシ、チョウザメにおける有害物質汚染と影響に関する研究
    2000 -2002
  • 非制御燃焼過程におけるダイオキシン類等の残留性有機汚染物質の生成と挙動
    2000 -2002