Concentrations and fluxes of salmon-derived polychlorinated biphenyls (PCBs) in lake sediments.
Fourteen sediment cores were collected from 10 lakes spanning a large gradient of sockeye salmon returns (0-40 000 spawners km(-2)) in Alaska and British Columbia in 1995-98 and 2002/03. The cores were analyzed for 210Pb to determine sedimentation rates and focusing factors. Polychlorinated biphenyl (PCBs) concentrations in the surface sediments (0-2 cm) were highly correlated with the number of sockeye salmon returns to each nursery lake. For 2002/03, the correlation between PCB concentration and number of salmon spawners was best with no correction factors applied, but decreased considerably when corrected for sedimentation rates, and was improved again by correcting for sediment focusing. Although sigmaPCB concentrations were similar in 1995-98 and 2002/03, the congener patterns varied. Because salmon are the dominant source of PCBs for most of these lakes, variation in sediment congener pattern likely derives from variation in congener patterns carried by the salmon. Overall, total PCB input by salmon has remained relatively constant since 1995. Unlike temperate Great Lakes contaminant studies, the North American west-coast lakes dominated by salmon bio-transport showed no sign of recent decrease in PCBs.
Krümmel
Eva M
EM
Department of Biology, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario KiN 6N5, Canada. eva.kruemmel@science.uottawa.ca
Gregory-Eaves
Irene
I
Macdonald
Robie W
RW
Kimpe
Lynda E
LE
Demers
Marc J
MJ
Smol
John P
JP
Finney
Bruce
B
Blais
Jules M
JM
D000413:Alaska; D000818:Animals; D001955:British Columbia; D017753:Ecosystem; D004777:Environment; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis; D005399:Fishes; D020387:Food Chain; D019015:Geologic Sediments / Q000032:analysis*; D007856:Lead Radioisotopes / Q000032:analysis; D011075:Polybrominated Biphenyls; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D012474:Salmon; D012989:Soil Pollutants; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000032:analysis
D004785:Environmental Pollutants; D007856:Lead Radioisotopes; D011075:Polybrominated Biphenyls; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls