Geographic variation of chlorinated hydrocarbons in burbot (Lota lota) from remote Lakes and Rivers in Canada

Abstract

The variation in levels of polychlorinated biphenyls (sigma PCBs), chlorobenzenes and chlorinated pesticides was studied in burbot (Lota lota) from eight remote locations along a northwesterly transect from northwestern Ontario to the Mackenzie River delta in Canada. Significant declines in concentrations of PCB congeners, DDT isomers (sigma DDT), lindane, dieldrin, and mirex in burbot liver were found with increasing north latitude. Mean sigma PCB concentrations ranged from 1,290 ng/g (lipid wt) at Lake 625, a remote lake in northwestern Ontario, to 301 ng/g in samples from the Mackenzie River at Arctic Red River, N.W.T. No significant differences in mean concentrations of toxaphene, alpha-HCH, tri- and tetrachlorobiphenyls were observed between southern and northern sampling sites. Toxaphene was the predominant organochlorine residue in northern fish samples averaging 1,400 ng/g (lipid wt) at the three most northerly sites and 1,723 ng/g at Lake 625. Airborne contamination was the only likely source of organochlorines for most of the locations surveyed. The results were consistent with the hypothesis that inputs of semi-volatile organochlorines to northern aquatic ecosystems decrease with increasing north latitude and distance from North American sources.

Historically and Currently Used Dechloranes in the Sediments of the Great Lakes

“…The concentration of mirex in fish liver in Canadian lakes was also found to decline with increasing latitude ranging from about 43°to 62°North. 20 Lake Ontario sites are outliers in the regression against latitude. Apparently, the sediments there have accumulated much more mirex than the regression equation describes.…”

Sex Differences in Hepatic Lipids of Toxaphene-Exposed Juvenile Yellowtail Flounder (Pleuronectes ferrugineus Storer)

“…50 year), its atmospheric transport from dump sites (41 Â 10 6 tons) and countries where it is still being applied (e.g., South America, Africa, Eastern Europe, the Indian subcontinent, and the former Soviet Union), and its bioaccumulation in lipid-rich tissues, particularly in aquatic organisms (Brooks, 1974;Duke, 1977, Fa˚hraeus-Van Ree andPayne, 1997;Loewen et al, 1998, Oetjen andKarl, 1998;Kucklick and Baker, 1998;Fa˚hraeus-Van Ree and Spurrell, 2000). Rather high concentration of Toxaphene [e.g.,303.0 mg/kg wet weight lake trout (Salvelinus namaycush) and 1723 ng/g lipid weight burbot (Lota lota) have been demonstrated in fish from remote lakes with no record of Toxaphene usage (Muir et al, 1990;Donald et al, 1998).…”

Effect of Toxaphene on Isolated Hepatocytes of the Yellowtail Flounder, Pleuronectes ferrugineus Storer

“…Surface concentrations of Toxaphene in sediment cores (15$4}33 $12 ng/g) from the Great Lakes (Superior, Michigan, and Ontario) and concentrations of Toxaphene in lake trout (Salvelinus namaycush; 0.54}6.7 g/g wet weight) from these lakes have been reported (Pearson et al, 1997;Glassmeyer et al, 1997). Fish from remote lakes with no record of Toxaphene usage have demonstrated rather high concentrations of Toxaphene, e.g., 303.0 g/kg wet weight lake trout (S. namaycush) and 1723 ng/g lipid weight burbot (¸ota lota), because of the length of time of exposure, long-range transport of Toxaphene, and ecological or limnological factors (Donald et al, 1998;Muir et al, 1990).…”