Contamination of the Great Lakes

The US General Accounting Office in the US estimates that 56 million pounds of pesticides end up in the Great Lakes every year, including 46 million used on crops, eight million pounds on lawns and more than two million pounds used on golf courses. Pesticides that are repeatedly applied during the year on fruits and vegetables enter the Great Lakes and stay there, becoming more concentrated with time. The long retention time allows some pesticides to settle in lake-bottom sediments and become absorbed into the food chain. High levels of banned pesticides are still showing up in fish tissue. Preliminary findings by the Environmental Protection Agency (EPA) show that the effects of nine pesticides in current use may be more long lasting than once thought. Data also indicate that millions of pounds of unusable pesticides being stored on farms present a disposal problem for the Great Lakes region.

Issues concerning pesticides used in the Great Lakes watershed, GAO/RCED-93-128, 14 June 1993.

[This article first appeared in Pesticides News No.21,September 1993, page 20]