WA7 Bioaccumulation and Biotransformation of POPs
Room 18C/D, Level 4
8:00 AM - 12:00 PM, Wednesday, 12 November 2003
Chair: Letcher, Robert ,
Co-chair: Fisk, Aaron ,
(384) Bioaccumulation and biotransformation of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in juvenile American kestrels.
Drouillard, Ken1, Balkwill, Karen1, Letcher, Robert1, Fernie, Kim2, Shutt, Laird3, 1 Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P42 Canadian Wildlife Service, Burlington, ON, Canada3 Canadian Wildlife Service, Ottawa, ON, Canada
ABSTRACT- Increasing trends in environmental concentrations of polybrominated diphenyl ethers (PBDEs) has generated concerns about the toxicology and bioaccumulative potential of these compounds. PBDEs are structurally similar to PCBs and bioaccumulate in aquatic food webs. However, the bioaccumulation potential of PBDEs in birds remains less well characterized. This study determined the bioaccumulation of PBDEs and PCBs in juvenile American kestrels. Animals were exposed to PBDEs or PCBs by injection to yolk sac to produce whole egg concentrations similar to those found in Lake Ontario herring gull eggs (1.5 ppm). After hatching the juveniles were further fed a diet of ground chicks spiked with either PBDEs or PCBs at concentrations similar to those found in Lake Ontario Alewife. Chicks were sacrificed at fledgling (21 d) and homogenized to determine congener profiles and chemical mass balance. PCB congener patterns in juvenile kestrels differed from the dosing mixture and exhibited a depletion of congeners with vicinal, hydrogen substituents at a meta-para sites on one of the phenyl rings. These data indicate that juvenile American kestrels possess similar PCB biotranformation capacities as adults. PBDE biotransformation was evident for higher brominated congeners and bioaccumulation potentials were lower then observed for PCBs of equivalent hydrophobicity. The data indicate that PBDEs do not exhibit the same capacity to biomagnify in birds as PCBs.
Key words: birds, PBDEs, biomagnification, biotransformation