WP6 Emerging Pollutants
Wednesday, 16 November 2005: 8:00 AM - 6:30 PM in Exhibit Hall
(LET-1117-814447) Brominated flame retardants and methoxylated and hydroxylated PBDEs in two Norwegian arctic top-predators: glaucous gulls and polar bears.
Verreault, J.1, 2, Gabrielsen, G.1, Chu, S.3, Muir, D.4, Andersen, M.1, Letcher, R.2, 3, 1 Norwegian Polar Institute, Tromso, Norway2 Environment Canada, Canadian Wildlife Service, National Wildlife Research Centre, Ottawa, Ontario, Canada3 University of Windsor, Great Lakes Institute for Environmental Research, Windsor, Ontario, Canada4 Environment Canada, Canada Centre for Inland Waters, National Water Research Institute, Burlington, Ontario, Canada
ABSTRACT- Brominated flame retardants (BFRs) have been subject of a particular environmental focus in the Arctic. The present study investigated the congener patterns and levels of total- hexabromocyclododecane (HBCD), polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), as well as structural analogues to PBDEs, i.e. the methoxylated (MeO) and hydroxylated (OH) PBDEs, in plasma samples of glaucous gulls (Larus hyperboreus) and polar bears (Ursus maritimus) from the Norwegian Arctic. The analyses revealed the presence of total-HBCD and BB101 in glaucous gull samples, but generally found infrequently (14% of samples) in samples at low or non-detectable in polar bears. Sum concentrations of 12 PBDE congeners (
12PBDE) monitored in glaucous gulls (range: 8.23 - 67.5 ng/g wet wt) largely surpassed those of polar bears (range: 2.65 - 9.72 ng/g wet wt). Two higher brominated PBDEs, BDE183 and BDE209, were detected at low levels, and thus are bioaccumulating to a limited degree in glaucous gulls. In polar bear plasma, BDE183 was below the detection limit for all animals, and BDE209 was only detected in 7% of the samples. Of the 15 MeO-PBDEs analyzed, 3-MeO-BDE47 was consistently dominant in glaucous gulls and polar bears, followed by 4'-MeO-BDE49 and 6-MeO-BDE47. The 3-OH-BDE47, 4'-OH-BDE49 and 6-OH-BDE47 congeners were also detected in glaucous gulls, although in polar bears 4'-OH-BDE49 was the only congener quantifiable in 13% of the samples. The presence of MeO- and OH-PBDEs in plasma of both species suggests possible dietary uptake from naturally-occurring sources (e.g., marine sponges and green algae), but also metabolically-derived biotransformation of PBDEs such as BDE47 could be a contributing factor. Our findings suggest that there are dissimilar biochemical mechanisms involved in PCB and PBDE metabolism and accumulation/elimination, and/or OH-PBDE accumulation and retention in Norwegian glaucous gulls and polar bears.
Key words: PBDEs, PBDE analogues, glaucous gull/polar bear, Arctic (Norway)