Testing prompted by an Associated Press story that revealed trace amounts of pharmaceuticals in drinking water supplies has shown that more Americans are affected by the problem than previously thought - at least 46 million.
That's up from 41 million people reported by the AP in March as part of an investigation into the presence of pharmaceuticals in the nation's waterways.
The AP stories prompted federal and local legislative hearings, brought about calls for mandatory testing and disclosure, and led officials in at least 27 additional metropolitan areas to analyze their drinking water. Positive tests were reported in 17 cases, including Reno, Nev., Savannah, Ga., Colorado Springs, Colo., and Huntsville, Ala. Results are pending in three others.
The test results, added to data from communities and water utilities that bowed to pressure to disclose earlier test results, produce the new total of Americans known to be exposed to drug-contaminated drinking water supplies.
The overwhelming majority of U.S. cities have not tested drinking water while eight cities - including Boston, Phoenix and Seattle - were relieved that tests showed no detections.
"We didn't think we'd find anything because our water comes from a pristine source, but after the AP stories we wanted to make sure and reassure our customers," said Andy Ryan, spokesman for Seattle Public Utilities.
The substances detected in the latest tests mirrored those cited in the earlier AP report.
Chicago, for example, found a cholesterol medication and a nicotine derivative. Many cities found the anti-convulsant carbamazepine. Officials in one of those communities, Colorado Springs, say they detected five pharmaceuticals in all, including a tranquilizer and a hormone.