Enantiomer-specific accumulation of PCB atropisomers in the bowhead whale (Balaena mysticetus).
Blubber (n = 40) and liver (n = 20) samples from the bowhead whale (Balaena mysticetus) were collected during the 1997-1998 Native (Inuit) subsistence harvests in Barrow, AK. Bowhead tissues and zooplankton were analyzed for polychlorinated biphenyl (PCB) concentrations and the enantiomeric fractions (EFs) of eight chiral PCB congeners (PCB-91, 95, 135, 136, 149, 174, 176, and 183) to quantify the enantiomer-specific accumulation of PCBs in this cetacean. PCB concentrations in bowhead blubber were low (mean +/- 1 SE: 610 +/- 54 ng g(-1) lipid) relative to other cetaceans. The accumulation of several chiral PCBs (PCB-91, 135, 149, 174, 176, and 183) in bowhead blubber was enantiomer-specific relative to bowhead liver and zooplankton, suggesting that biotransformation processes within the bowhead whale are enantioselective. The EFs for PCB-95 and 149 were significantly correlated with body length in male and female whales, while EFs for PCB-91 correlated with length in males only. Despite evidence for enantioselective biotransformation, all three congeners bioaccumulated in the bowhead relative to PCB-153. Results suggest that enantioselective accumulation of PCB-91, 95, and 149 is influenced by PCB concentrations, age, and/or the modification of an uncharacterized stereoselective process (or processes) during sexual maturity.
Hoekstra
Paul F
PF
Department of Environmental Biology, University of Guelph, Ontario, Canada. paul.hoekstra@ec.gc.ca
Wong
Charles S
CS
O'Hara
Todd M
TM
Solomon
Keith R
KR
Mabury
Scott A
SA
Muir
Derek C G
DC
D000273:Adipose Tissue / Q000737:chemistry; D000367:Age Factors; D000818:Animals; D001824:Body Constitution; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000493:pharmacokinetics*; D005260:Female; D007536:Isomerism; D008297:Male; D011078:Polychlorinated Biphenyls / Q000737:chemistry / Q000493:pharmacokinetics*; D012737:Sex Factors; D014018:Tissue Distribution; D014907:Whales; D015048:Zooplankton / Q000737:chemistry
D004785:Environmental Pollutants; D011078:Polychlorinated Biphenyls