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Janneche Utne Skaare - One of the best experts on this subject based on the ideXlab platform.
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does high Organochlorine oc exposure impair the resistance to infection in polar bears ursus maritimus part i effect of ocs on the humoral immunity
Journal of Toxicology and Environmental Health, 2004Co-Authors: Elisabeth Lie, Andrew E. Derocher, Øystein Wiig, Ross J. Norstrom, Stig Larsen, Hans Jorgen S Larsen, Grethe Marie Johansen, Nicholas J Lunn, Janneche Utne SkaareAbstract:This study was undertaken to assess if high levels of Organochlorines (OCs) are associated with decreased ability to produce antibodies in free-ranging polar bears (Ursus maritimus) and thus affect the humoral immunity. In 1998 and 1999, 26 and 30 polar bears from Svalbard, Norway, and Churchill, Canada, respectively, were recaptured 32–40 d following immunization with inactivated influenza virus, reovirus, and herpes virus and tetanus toxoid. Blood was sampled at immunization and at recapture for determination of plasma levels of polychlorinated biphenyls (PCBs) and Organochlorine pesticides (OCPs), serum immunoglobulin G (IgG) concentrations, and specific antibodies against influenza virus, reovirus, and herpes virus, tetanus toxoid, and Mannheimia haemolytica. The OCs alone contributed with up to 7% to the variations in the immunological parameters. The combination of ∑PCBs (sum of 12 individual PCB congeners), ∑OCPs (sum of 6 OCPs), and biological factors accounted for 40–60% of the variation in the i...
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Organochlorines affect the major androgenic hormone testosterone in male polar bears ursus maritimus at svalbard
Journal of Toxicology and Environmental Health, 2003Co-Authors: Irma C Oskam, Andrew E. Derocher, Øystein Wiig, Erik Ropstad, Elisabeth Lie, Ellen Dahl, Stig Larsen, Richard Wiger, Janneche Utne SkaareAbstract:Normal sexual development and subsequent reproductive function are dependent on appropriate testosterone production and action. The regulation of steroid hormones, including androgens, can be influenced by both biological and environmental factors, including environmental chemicals. Concentrations of Organochlorines are considerably greater in Svalbard polar bears than in polar bears from other regions. Between 1995 and 1998, samples were collected from 121 male polar bears (Ursus maritimus) from the Svalbard area. In this study, testosterone concentration variations were described for male polar bears during different seasons and for all age groups. To study possible relationships between plasma testosterone concentrations and biological factors, such as age, axial girth, and extractable plasma fat, and Organochlorine contaminants including hexachlorocyclohexanes, hexachlorobenzene, chlordanes, p,p'-DDE, and 16 individual polychlorinated biphenyl (PCB) congeners, identical statistical analyses were performed on the total population and a subsample of reproductively active adults. Of the biological factors, axial girth showed a significant positive relationship and percentage extractable fat and a significant negative relationship with the testosterone concentrations. Both the epsilon pesticides and epsilon PCBs made significant negative contributions to the variation of the plasma testosterone concentration. The continuous presence of high concentrations of Organochlorines in male polar bears throughout their life could possibly aggravate any reproductive toxicity that may have occurred during fetal and early postnatal development.
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differences in contamination load between pelagic and sympagic invertebrates in the arctic marginal ice zone influence of habitat diet and geography
Marine Ecology Progress Series, 2002Co-Authors: Katrine Borga, Geir W Gabrielsen, Janneche Utne SkaareAbstract:Concentration and transport of organic pollutants by Arctic sea ice may expose ice- associated fauna to high contaminant concentrations relative to pelagic organisms. Zooplankton and ice-associated amphipods were collected in the marginal ice zone near Svalbard to investigate whether habitat, diet and geographic sampling site influenced their Organochlorine burden. Organo- chlorine concentrations were low in both zooplankton (Calanus hyperboreus, Thysanoessa inermis, Parathemisto libellula, Chaetognatha) and ice-associated amphipods (Apherusa glacialis, Gammarus wilkitzkii, Onisimus spp.), from 0.3 ng g -1 lipid weight trans-chlordane in A. glacialis to 36.9 ng g -1 lipid weight hexachlorobenzene (HCB) in G. wilkitzkii. Diet accounted for most of the explained Organochlorine variance, followed by habitat and geographic sampling site. The concentrations were higher in carnivores (P. libellula, Chaetognatha, G. wilkitzkii, Onisimus spp.) than in herbivores (C. hyperboreus, T. inermis, A. glacialis). In comparison with zooplankton, ice fauna had high levels of Organochlorines with high residence time in surface layers (hexachlorocyclohexane (HCH) and HCB), whereas compounds with higher particle affinity did not differ between habitats. This was attributed to the sea ice serving as a habitat that keeps ice fauna in the surface layer, rather than to the release of contaminants from the sea ice itself. HCHs were the only compounds that differed geo- graphically. Higher α -/γ-HCH ratios in C. hyperboreus and A. glacialis from the Greenland Sea rela- tive to North of Svalbard, are consistent with the geographic patterns in HCH levels reported for air, water, ringed seals Phoca hispida and polar bears Ursus maritimus.
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biomagnification of Organochlorines along a barents sea food chain
Environmental Pollution, 2001Co-Authors: Katrine Borga, Geir Wing Gabrielsen, Janneche Utne SkaareAbstract:To trace the biomagnification of Organochlorines in marine food chains near Svalbard, which may lead to the high Organochlorine concentrations in top predators from the area, we compared concentrations and patterns of Organochlorines in selected taxa. The pelagic crustaceans, Calanus spp. (copepods), Thysanoessa spp. (euphausiids), Parathemisto libellula (amphipod), and the fish species, Boreogadus saida (polar cod) and Gadus morhua (cod) were selected to represent the lower trophic levels in the food web. Four seabird species were chosen at the higher trophic levels, Uria lomvia (Brunnich's guillemot), Cepphus grylle (black guillemot), Rissa tridactyla (black-legged kittiwake) and Larus hyperboreus (glaucous gull). We found low concentrations of the Organochlorines Σhexachlorocyclohexanes (ΣHCHs), hexachlorobenzene (HCB), ΣChlordanes, ΣDDTs and Σpolychlorinated biphenyls (ΣPCBs) in crustaceans (11–50 ng g−1 lipid wt.) and fish (15–222 ng g−1 lipid wt.). In seabirds, the Organochlorine concentrations biomagnified one to three orders of magnitude dependent on species and compound class. Glaucous gulls had the highest concentrations of all Organochlorines. The Organochlorine levels in all taxa except glaucous gull were comparable to those recorded in similar species in the Canadian Arctic. The Organochlorine pattern changed from crustaceans and fish to seabirds. Moving up the food chain, the relative contribution of ΣHCHs, HCB and ΣChlordanes decreased, and the relative contribution of ΣDDTs, ΣPCBs, persistent compounds and metabolites increased. The results reflected trophic transfer of Organochlorines along the food chain as well as different elimination potentials due to direct diffusion in crustaceans and fish, and higher contaminant metabolic activity in seabirds.
Shinsuke Tanabe - One of the best experts on this subject based on the ideXlab platform.
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Organohalogen compounds in human breast milk from Republic of Buryatia, Russia.
Environmental pollution (Barking Essex : 1987), 2006Co-Authors: Oyuna Tsydenova, Natsuko Kajiwara, Agus Sudaryanto, Tatsuya Kunisue, Valeriy Batoev, Shinsuke TanabeAbstract: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, BDE-153, 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.
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contamination and toxic effects of persistent endocrine disrupters in marine mammals and birds
Marine Pollution Bulletin, 2002Co-Authors: Shinsuke TanabeAbstract:In recent years, several species of marine mammals and birds have been affected by uncommon diseases and unusual mortalities. While several possible causative factors have been attributed for these events, a prominent suspect is exposure to man-made toxic contaminants. Particularly, some of these man-made chemicals can disrupt normal endocrine physiology in animals. At CMES, our studies focus on exposure and toxic effects of endocrine disrupting chemicals, particularly Organochlorines, in higher trophic level wildlife. Endocrine disrupting chemicals, such as Organochlorine insecticides, polychlorinated biphenyls, organotins etc. are found in tissues of a wide variety of wildlife. Extremely high concentrations have been found in animals afflicted with diseases and/or victims of mass mortalities. Elevated contamination by Organochlorines has been found in open sea animals such as cetaceans and albatrosses, which seemed to be attributable to their low capacity to metabolize toxic persistent contaminants. Significant correlations between biochemical parameters (serum hormone concentrations and cytochrome P450 enzyme activities) and residues of endocrine disrupting chemicals were found in some species of marine animals, which indicates that these chemicals may impose toxic effects in animals even at the current levels of exposure. In general, water birds and marine mammals accumulated the dioxin-like compounds with much higher concentrations than humans, implying higher risk from exposure in wildlife. The future issues of endocrine disrupting chemicals in humans and wildlife will have to be focused in developing countries.
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Organochlorine and organotin compounds in caspian seals phoca caspica collected during an unusual mortality event in the caspian sea in 2000
Environmental Pollution, 2002Co-Authors: Natsuko Kajiwara, Shinsuke Tanabe, Satoko Niimi, Michio X Watanabe, Y Ito, Shin Takahashi, Lev S Khuraskin, Nobuyuki MiyazakiAbstract: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 microg/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.
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contamination levels and specific accumulation of persistent Organochlorines in caspian seal phoca caspica from the caspian sea russia
Archives of Environmental Contamination and Toxicology, 1999Co-Authors: Mafumi Watanabe, Ryo Tatsukawa, Shinsuke Tanabe, Masao Amano, Nobuyuki Miyazaki, E A Petrov, S L KhuraskinAbstract: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 μg/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.
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persistent Organochlorine residues in harbour porpoise phocoena phocoena from the black sea
Marine Pollution Bulletin, 1997Co-Authors: Shinsuke Tanabe, Ryo Tatsukawa, Nobuyuki Miyazaki, Bathini Madhusree, Ayaka Amaha Ozturk, Emin Ozdamar, Orhan Aral, Osman Samsun, Bayram OzturkAbstract:A wide range of Organochlorine residues were determined in the blubber of harbour porpoises from the Black Sea. Concentrations of DDTs (8.3–180 μg g−1 wet weight) were the highest followed by PCBs (1.6–39 μg g−1), HCHs (1.5–17 μg g−1), CHLs (0.11 – 2.4, μg g−1) and HCB (0.057 – 0.61 μg g−1). The composition of DDT and its metabolites was in the order of p,p′-DDT (46%), ac>t-DDD (34%), p,p′-DDT (16%) and o,p′-DDT (4%). A similar pattern was also observed in fish from the Black Sea. Relatively higher concentrations of p,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. It 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.
Ryo Tatsukawa - One of the best experts on this subject based on the ideXlab platform.
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contamination levels and specific accumulation of persistent Organochlorines in caspian seal phoca caspica from the caspian sea russia
Archives of Environmental Contamination and Toxicology, 1999Co-Authors: Mafumi Watanabe, Ryo Tatsukawa, Shinsuke Tanabe, Masao Amano, Nobuyuki Miyazaki, E A Petrov, S L KhuraskinAbstract: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 μg/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.
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persistent Organochlorine residues in harbour porpoise phocoena phocoena from the black sea
Marine Pollution Bulletin, 1997Co-Authors: Shinsuke Tanabe, Ryo Tatsukawa, Nobuyuki Miyazaki, Bathini Madhusree, Ayaka Amaha Ozturk, Emin Ozdamar, Orhan Aral, Osman Samsun, Bayram OzturkAbstract:A wide range of Organochlorine residues were determined in the blubber of harbour porpoises from the Black Sea. Concentrations of DDTs (8.3–180 μg g−1 wet weight) were the highest followed by PCBs (1.6–39 μg g−1), HCHs (1.5–17 μg g−1), CHLs (0.11 – 2.4, μg g−1) and HCB (0.057 – 0.61 μg g−1). The composition of DDT and its metabolites was in the order of p,p′-DDT (46%), ac>t-DDD (34%), p,p′-DDT (16%) and o,p′-DDT (4%). A similar pattern was also observed in fish from the Black Sea. Relatively higher concentrations of p,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. It 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.
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persistent Organochlorines in steller sea lion eumetopias jubatus from the bulk of alaska and the bering sea 1976 1981
Marine Pollution Bulletin, 1996Co-Authors: Jong Su Lee, Thomas R. Loughlin, Ryo Tatsukawa, Shinsuke Tanabe, H Umino, D C CalkinsAbstract:Abstract 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 μg g−1 (lipid weight) in males and from 0.57 to 16 μg g−1 in females. Concentrations of DDTs (DDT and its metabolites) in the blubber ranged from 2.8 to 17 μg g−1 in males and from 0.19 to 6.5 μg 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.
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geographical distribution and accumulation features of Organochlorine residues in fish in tropical asia and oceania
Environmental Science & Technology, 1995Co-Authors: Kurunthachalam Kannan, Shinsuke Tanabe, Ryo TatsukawaAbstract: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.
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global contamination by persistent Organochlorines and their ecotoxicological impact on marine mammals
Science of The Total Environment, 1994Co-Authors: Hisato Iwata, Ryo TatsukawaAbstract:The present paper overviews the global contamination by persistent Organochlorines and their ecotoxicological implications on marine mammals. The recent pattern of contamination by Organochlorine residues in the coastal environment is prominent in tropical regions due to continuous usage in the low-latitude developing countries. The major emission source of Organochlorines is probably the tropical belt and large quantities of volatilized contaminants are dispersed through the atmosphere on global terms. Reflecting this, a considerable contamination was observed in open ocean tropical waters as well as in the Arctic and nearby waters. The study of the mass transfer of Organochlorines at the air-water interface suggests that the oceanic water bodies, particularly Arctic waters, act as a sink for persistent contaminants. In this regard, the marine mammals, particularly cetaceans, are one of the animal groups receiving high concentrations of persistent Organochlorines arising out of a worldwide contamination. They can amplify much greater amounts of toxic contaminants through feeding and also pass them in large quantities from one generation to the next through lactation. Unfortunately, these animals have a smaller capacity for degradation of these contaminants due to the specific mode of cytochrome P-450 enzyme systems. These drug-metabolizing enzyme systems may be related to the possible effects of persistent Organochlorines, particularly coplanar PCBs. Furthermore, the residue levels of these contaminants in marine mammals are unlikely to decline in the near future. Considering all these facts, it may be concluded that marine mammals are one of the most vulnerable and possible target organisms with regard to long-term toxicity of hazardous man-made chemicals in the future.
Nobuyuki Miyazaki - One of the best experts on this subject based on the ideXlab platform.
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differences in Organochlorine accumulation in masu salmon oncorhynchus masou masou between fluvial and sea run forms
Water Air and Soil Pollution, 2007Co-Authors: Mayuko Oka, Takaomi Arai, Nobuyuki MiyazakiAbstract:Masu salmon Oncorhynchus masou masou divides into two life histories after a year of life in the river, the sea-run form and the fluvial form. Since salmons are anadromous, the sea-run form salmons are known to pollute the river sediments during spawning migration. In this study, we have studied the accumulation of Organochlorines in the fluvial form as well as the sea-run form, and discussed their differences. In order to elucidate the accumulation patterns of Organochlorines in both the fluvial and sea-run form masu salmons, the concentrations of Organochlorines were determined in the muscle of both life histories. The Organochlorines in the sea-run form were 7 to 21 times higher than those of fluvial form. Since salmons are semelparous, the carcasses of polluted sea-run form pollute the river sediments. The trans-nonachlor/trans-chlordane (N/C) ratio in the fluvial form (1.93) was significantly lower than that of sea-run form (23.8). This indicates that the fluvial form is polluted by comparatively newly input chemicals. These results suggest that sea-run form masu salmons have the potential to pollute the river sediments secondarily as vectors, but from the difference in N/C ratio between the two forms, the fluvial fish does not seem to be polluted by those Organochlorine compounds of sea-run fish origin yet.
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Organochlorine and organotin compounds in caspian seals phoca caspica collected during an unusual mortality event in the caspian sea in 2000
Environmental Pollution, 2002Co-Authors: Natsuko Kajiwara, Shinsuke Tanabe, Satoko Niimi, Michio X Watanabe, Y Ito, Shin Takahashi, Lev S Khuraskin, Nobuyuki MiyazakiAbstract: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 microg/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.
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contamination levels and specific accumulation of persistent Organochlorines in caspian seal phoca caspica from the caspian sea russia
Archives of Environmental Contamination and Toxicology, 1999Co-Authors: Mafumi Watanabe, Ryo Tatsukawa, Shinsuke Tanabe, Masao Amano, Nobuyuki Miyazaki, E A Petrov, S L KhuraskinAbstract: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 μg/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.
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persistent Organochlorine residues in harbour porpoise phocoena phocoena from the black sea
Marine Pollution Bulletin, 1997Co-Authors: Shinsuke Tanabe, Ryo Tatsukawa, Nobuyuki Miyazaki, Bathini Madhusree, Ayaka Amaha Ozturk, Emin Ozdamar, Orhan Aral, Osman Samsun, Bayram OzturkAbstract:A wide range of Organochlorine residues were determined in the blubber of harbour porpoises from the Black Sea. Concentrations of DDTs (8.3–180 μg g−1 wet weight) were the highest followed by PCBs (1.6–39 μg g−1), HCHs (1.5–17 μg g−1), CHLs (0.11 – 2.4, μg g−1) and HCB (0.057 – 0.61 μg g−1). The composition of DDT and its metabolites was in the order of p,p′-DDT (46%), ac>t-DDD (34%), p,p′-DDT (16%) and o,p′-DDT (4%). A similar pattern was also observed in fish from the Black Sea. Relatively higher concentrations of p,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. It 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.
Derek C G Muir - One of the best experts on this subject based on the ideXlab platform.
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is bone mineral composition disrupted by Organochlorines in east greenland polar bears ursus maritimus
Environmental Health Perspectives, 2004Co-Authors: Christian Sonne, Rune Dietz, Erik W Born, Frank Riget, Maja Kirkegaard, Lars Hyldstrup, Robert J Letcher, Derek C G MuirAbstract:We analyzed bone mineral density (BMD) in skulls of polar bears (Ursus maritimus) (n = 139) from East Greenland sampled during 1892–2002. Our primary goal was to detect possible changes in bone mineral content (osteopenia) due to elevated exposure to Organochlorine [polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane (DDT) and its metabolites, chlordanes (CHLs), dieldrin, hexacyclohexanes, hexachlorobenzene] and polybrominated diphenyl ether (PBDE) compounds. To ensure that the BMD value in skull represented the mineral status of the skeletal system in general, we compared BMD values in femur and three lumbar vertebrae with skull in a subsample. We detected highly significant correlations between BMD in skull and femur (r = 0.99; p < 0.001; n = 13) and skull and vertebrae (r = 0.97; p < 0.001; n = 8). BMD in skulls sampled in the supposed pre-Organochlorine/PBDE period (1892–1932) was significantly higher than that in skulls sampled in the supposed pollution period (1966–2002) for subadult females, subadult males, and adult males (all, p < 0.05) but not adult females (p = 0.94). We found a negative correlation between Organochlorines and skull BMD for the sum of PCBs (∑PCB; p < 0.04) and ∑CHL (p < 0.03) in subadults and for dieldrin (p < 0.002) and ∑DDT (p < 0.02) in adult males; indications for ∑PBDE in subadults were also found (p = 0.06). In conclusion, the strong correlative relationships suggest that disruption of the bone mineral composition in East Greenland polar bears may have been caused by Organochlorine exposure.
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immune functions in the fisher rat fed beluga whale delphinapterus leucas blubber from the contaminated st lawrence estuary
Environmental Research, 1999Co-Authors: P Lapierre, Ross J. Norstrom, Derek C G Muir, S De Guise, Pierre Beland, Michel FournierAbstract:In order to assess the immunotoxic potential of food naturally contaminated with PCBs and other organohalogens, Fisher rats were fed a diet in which the lipids originated from the blubber of either a highly polluted St. Lawrence beluga or a relatively uncontaminated Arctic beluga. After a period of 2 months, different immune functions were evaluated, including lymphoblastic transformation, natural killer cell activity, plaque-forming cells, phagocytosis, oxidative burst, and immunophenotyping. For all assays, rats fed a St. Lawrence beluga blubber diet or a mixture of Arctic and St. Lawrence beluga blubber diet were not different from control rats fed a diet containing Arctic beluga blubber. These results are inconsistent with the well-known immunosuppressive effects of Organochlorines in numerous species and with the lesions suggestive of Organochlorine-related immunosuppression that are observed in St. Lawrence belugas. The lack of observable immunotoxic effects in rats fed contaminated beluga blubber might be explained by antagonistic effects in the organohalogen mixture, by a response specific to the rat, by a strain-related lack of sensitivity to Organochlorines, or by insufficient dose due to the shortness of the exposure period or the route of exposure.
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can seal eating explain elevated levels of pcbs and Organochlorine pesticides in walrus blubber from eastern hudson bay canada
Environmental Pollution, 1995Co-Authors: Derek C G Muir, Mark D Segstro, Keith A Hobson, C A Ford, R E A Stewart, S OlpinskiAbstract:Walrus (Odobenus rosmarus) blubber samples from Inukjuak and Akulivik (East Hudson Bay), Foxe Basin (Igloolik and Hall Beach) and Loks Land (East Baffin Island) were analysed for PCB congeners (ortho and non-ortho substituted) and other persistent Organochlorines (DDT, toxaphene, chlordanes, dieldrin, mirex), as well as chlorinated dioxins/furans, to document spatial trends in contaminants in Canadian Arctic marine biota. Samples from 19 of 53 individuals had concentrations of ΣPCBs greater than 1000 ng g−1 (wet wt); the remaining individuals had much lower concentrations (50–600 ng g−1). Highest concentrations were found in samples from Inukjuak where average concentrations in blubber of females (N = 9) were 1450 ± 954 ng g−1 toxaphene, 2750 ± 1780 ng g−1 ΣCHLOR, 2160 ± 925 ng g−1 ΣDDT and 4790 ± 2380 ng g−1 ΣPCB. ΣPCB and ΣDDT concentrations greater than 1000 ng g−1 were unexpected based on previous studies of walrus from Greenland and Alaska. Local contamination was ruled out because levels of all Organochlorines were elevated in each animal from Inukjuak, and elevated levels were also found in animals from Akulivik and Loks Land. Walrus from Inukjuak had δ13C and δ15N values in muscle intermediate between those of ringed seals (Phoca hispida) and those of walrus from Akulivik with low Organochlorine levels. There was a weak but significant correlation between and δ15N and (log)ΣPCB. The Inukjuak walrus also had higher proportions of highly chlorinated PCB congeners, and higher DDE/ΣDDT ratios than walrus from Igloolik or Akulivik. The results suggest that the walrus with elevated Organochlorines are feeding at a higher trophic level than those with low levels and are probably utilizing ringed seals for a portion of their diet.