Like pesticides, industrial chemicals have filtered into the ground-water and surface waters of streams and rivers. Metal degreasers and dry-cleaning fluids are among the most common contaminants of glacial aquifers. Both have been linked to cancer in humans. At last count, 415 dry cleaners throughout Illinois have poisoned soil, and at least 30 represent a threat to groundwater. An assessment of the Illinois environment concluded that chemical contamination “has become increasingly dispersed and dilute,” leaving residues that are “increasingly chemically exotic and whose health effects are not yet clearly understood.”

Sandra Steingraber. Living Downstream: An Ecologist’s Personal Investigation of Cancer and the Environment. Da Capo Press. Kindle Edition. Pg. 6.