U.S. manufacturers, including major drugmakers, have legally released at least 271 million pounds of pharmaceuticals into waterways that often provide drinking water — contamination the federal government has consistently overlooked, according to an Associated Press investigation.

Last year, the AP reported that trace amounts of a wide range of pharmaceuticals — including antibiotics, anti-convulsants, mood stabilizers and sex hormones — have been found in American drinking water supplies. Including recent findings in Dallas, Cleveland and Maryland’s Prince George’s and Montgomery counties, pharmaceuticals have been detected in the drinking water of at least 51 million Americans.