Chemicals’ showing up in wastewater effluent doesn’t necessarily mean they will be found in drinking water. But some studies have found prescription drugs in drinking water at parts-per-trillion levels. A federal study of 74 waterways used for drinking water in 25 states found 53 had traces of one or more pharmaceuticals.
There are currently no federal regulations of pharmaceuticals in waste or drinking water. However, 12 pharmaceuticals are currently on the Environmental Protection Agency’s list of chemicals under consideration for drinking water standards.
Most researchers expected that the large lakes would dilute pharmaceuticals quickly, but a
study this summer found the drugs contaminating Lake Michigan two miles from Milwaukee sewage outfalls.