How many contaminants are found in belugas?
Several dozen toxic chemicals of man-made origin have been discovered in St. Lawrence belugas tissues since 1982. While many of these contaminants likely have an impact on the beluga’s health, their precise effect remains unknown.
To go through the looking glass
Samples are removed from the fatty tissue, the liver and other organs of beluga carcasses found along the shores of the St. Lawrence. These samples are then analyzed in various Canadian laboratories.
Concentrations of toxic contaminants found in the tissues of St. Lawrence belugas are significantly higher than those measured in beluga populations of the Arctic. Concentrations of heavy metals, such as lead and mercury, are 2 to 15 times higher in St. Lawrence belugas. PCB and DDT levels are 25 times higher and mirex levels are 100 times higher. These differences suggest that, by way of the food web, the St. Lawrence belugas have been exposed to several contaminants over a long period of time
Pierre Béland, SLNIE, Derek Muir, mDepartment of Fisheries and Oceans Canada, and Ross Norstrom, Environment Canada.
Environment Canada, Department of Fisheries and Oceans Canada, United States Environmental Protection Agency, Medical Research Council of Canada, Natural Science & Engineering Council of Canada, Université du Québec à Montréal, Canadian Wildlife Toxicology Network, Wildlife Toxicology Fund, World Wildlife Fund Canada.
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