Industrial chemicals contaminate many species of fish that populate the Great Lakes, making them too hazardous for safe human consumption, says a Canadian conservation group. "The lakes continue to be polluted to such an extent that human health is threatened," says a report released yesterday that lists industrial pollutants such as dioxins, PCBs, and methyl mercury among the contaminants.
The study tested 13 locations along four of the five Great Lakes (excluding Lake Michigan, which lies within the US). Among the species analyzed were coho salmon, rainbow trout, walleye, pike, and lake trout. Lake Superior was least polluted, but overall the news was grim, with contaminant levels meriting government warnings about ingesting fish from parts of all four lakes.