ST. PAUL, Minn. (AP) - A new study by the Minnesota Pollution Control Agency has found widespread contamination by pharmaceutical drugs and other chemicals in the state's lakes and rivers.

Researchers with the agency found 27 chemicals in the lakes they studied. When studying rivers, they found 56 chemicals downstream of four wastewater treatment plants and 33 chemicals upstream of the plants.

Reports say that commonly found chemicals included DEET, disinfectants, antibiotics, hormones and pharmaceutical drugs.

More than 90 percent of the lake samples used in the study contained DEET, the active ingredient in insect repellent. The scientists also detected significant amounts of iopamidol and metformin, two drugs they hadn't seen before.

The agency plans to examine the environmental impact through further study.