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Concentrations, patterns and metabolites of organochlorine pesticides in relation to xenobiotic phase I and II enzyme activities in ringed seals (Phoca hispida) from Svalbard and the Baltic Sea
2009
Routti, Heli | Bavel, Bert van | Letcher, Robert J. | Arukwe, Augustine | Chu, Shaogang | Gabrielsen, Geir W.
The present study investigates the concentrations and patterns of organochlorine pesticides (OCPs) and their metabolites in liver and plasma of two ringed seal populations (Phoca hispida): lower contaminated Svalbard population and more contaminated Baltic Sea population. Among OCPs, p,p'-DDE and sum-chlordanes were the highest in concentration. With increasing hepatic contaminant concentrations and activities of xenobiotic-metabolizing enzymes, the concentrations of 3-methylsulfonyl-p,p'-DDE and the concentration ratios of pentachlorophenol/hexachlorobenzene increased, and the toxaphene pattern shifted more towards persistent Parlar-26 and -50 and less towards more biodegradable Parlar-44. Relative concentrations of the chlordane metabolites, oxychlordane and -heptachlorepoxide, to sum-chlordanes were higher in the seals from Svalbard compared to the seals from the Baltic, while the trend was opposite for cis- and trans-nonachlor. The observed differences in the OCP patterns in the seals from the two populations are probably related to the catalytic activity of xenobiotic-metabolizing enzymes, and also to differences in dietary exposure. Contrasting patterns of organochlorine pesticides in two ringed seal populations.
Mostrar más [+] Menos [-]Accumulation of trace elements in harp seals (Phoca groenlandica) from Pangnirtung in the Baffin Island, Canada
2011
Agusa, Tetsuro | Nomura, Kumiko | Kunito, Takashi | Anan, Yasumi | Iwata, Hisato | Tanabe, Shinsuke
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.
Mostrar más [+] Menos [-]Can seal eating explain elevated levels of PCBs and organochlorine pesticides in walrus blubber from Eastern Hudson Bay (Canada)?
1995
Muir, D.C.G. | Segstro, M.D. | Hobson, K.A. | Ford, C.A. | Stewart, R.E.A. | Olpinski, S. (Department of Fisheries and Oceans, Central and Arctic Region, Winnipeg, Manitoba R3T 2N6 (Canada))
Bioaccumulation profiles of polychlorinated biphenyls including coplanar congeners and possible toxicological implications in Baikal seal (Phoca sibirica)
1997
Nakata, H. | Tanabe, S. | Tatsukawa, R. | Amano, M. | Miyazaki, N. | Petrov, E.A. (Department of Life Environment Conservation, Ehime University, Tarumi 3-5-7, Matsuyama 790 (Japan))
Mercury pollution and the Saimaa ringed seal (Phoca hispida saimensis)
1998
Hyvarinen, H. | Sipila, T. | Kunnasranta, M. | Koskela, J.T. (Department of Biology, University of Joensuu, P.O. Box 111, FIN-80101 Joensuu (Finland))
PFAS profiles in three North Sea top predators: metabolic differences among species?
2013
Galatius, Anders | Bossi, Rossana | Sonne, Christian | Rigét, Frank Farsø | Kinze, Carl Christian | Lockyer, Christina | Teilmann, Jonas | Dietz, Rune
Profiles of seven compounds of perfluoro-alkyl substances (PFASs) were compared among three species of top predators from the Danish North Sea: the white-beaked dolphin (Lagenorhynchus albirostris), the harbor porpoise (Phocoena phocoena), and the harbor seal (Phoca vitulina). The seals had higher total burdens (757.8 ng g(-1) ww) than the dolphins (439.9 ng g(-1) ww) and the porpoises (355.8 ng g(-1) ww), probably a reflection of feeding closer to the shore and thus contamination sources. The most striking difference among the species was the relative contribution of perfluorooctanesulfonamide (PFOSA) to the profiles; the seals (0.1 %) had much lower levels than porpoises (8.3 %) and dolphins (26.0 %). In combination with the values obtained from the literature, this result indicates that Carnivora species including Pinnipedia have a much higher capacity of transforming PFOSA to perfluorooctane sulfonic acid (PFOS) than cetacean species. Another notable difference among the species was that the two smaller species (seals and porpoises) with supposedly higher metabolic rates had lower concentrations of the perfluorinated carboxylic acids, which are generally more easily excreted than perfluorinated sulfonamides. Species-specific characteristics should be recognized when PFAS contamination in marine mammals is investigated, for example, several previous studies of PFASs in cetaceans have not quantified PFOSA.
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