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Drug Pollution in Our Great Lakes

Oct 01, 2010 ● By Susan Campbell

Recent testing of Lake Michigan water has revealed the presence of pharmaceutical byproducts, raising concerns about potential long-term health threats to anyone drinking water from the Great Lakes. Particularly worrisome are the potential effects on children, whose developing bodies face greater contaminant risks because of their smaller size.

Low levels of cotinine, a nicotine by-product, and the cholesterol-modifying drug gemfibrozil are among the pharmaceutical compounds that scientists have found in Lake Michigan water to date. Although the levels of these byproducts are too low to show any immediate effects on human health, scientists say little is known about the long-term consequences of consuming them or how they might degrade or interact with other chemicals in the water.

Patient use is the main source of drugs in our water supply. Most drugs are secreted in human and pet urine, but they also wind up in our water through careless disposal. A 2009 University of Illinois-Chicago survey of 450 Cook County residents found that 32 percent discard their unused and expired medications in the toilet or sink, and 59 percent place them in the trash.

Other drugs enter the water through treatment plant and septic system effluent, runoff from uncontrolled landfills, industrial discharges, commercial animal feeding operations and manure applications. Most waste-water treatment plants are not able to remove pharmaceuticals.

Because the Great Lakes provide drinking water for more than 40 million people, this issue is urgent. Illinois lawmakers and policy-focused environmental groups are attempting to address residential and institutional disposal issues, but more work is needed.

Susan Campbell is the Communications Manager for Alliance for the Great Lakes. For more information on this topic, the studies that are underway and what you can do, visit the website of the Alliance for the Great Lakes at