(Press-News.org) The concentrations of many historically used, and now widely banned, pesticides and other toxic chemicals—called legacy contaminants—can become magnified in an animal that eats contaminated food; however, a new Environmental Toxicology & Chemistry study has found that Arctic mammals metabolize some currently used pesticides, preventing such 'biomagnification.'
Researchers who studied the vegetation-caribou-wolf food chain in the Bathurst region of Canada say that currently use pesticides enter the food chain and become concentrated in vegetation, but the evidence shows that they are not biomagnified through the diets of their consumers. "Since these pesticides replaced some legacy contaminants that do biomagnify in similar food chains, this is good news for the wildlife and the people of the Arctic who survive by hunting caribou and other animals," said first author Adam Morris. "But this is still only a small part of a much larger picture regarding replacement contaminants and how they're behaving compared with their legacy counterparts."
INFORMATION:
Mammals metabolize some pesticides to limit their biomagnification
2014-07-21
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