what's in your water?

Chicago's first tests for pharmaceutical drugs in Lake Michigan drinking water detected trace amounts of unregulated chemicals, though officials said the levels were extremely low and posed no health risks.

Responding to a Tribune story published last month that for the first time revealed small amounts of pharmaceuticals and other unregulated chemicals in local tap water, the city's water commissioner said Chicago will conduct its own tests once a month for at least the next year.

The only compound found in both the Tribune and city tests was cotinine, a nicotine byproduct that researchers consider to be an indicator of pharmaceuticals from human waste.

The city also found small amounts of gemfibrozil, a prescription cholesterol-fighting drug, in water from the Jardine plant, which serves neighborhoods north of 35th Street. The active ingredient in bug spray, DEET, was found in water from the South Side Treatment Plant at 78th Street.

Moreover, the city found nicotine and carbamazepine, a prescription anti-seizure drug, in untreated water on the South Side. The compounds were not found in treated water, though .