■ The Food and Drug Administration has updated its list of waste drugs that should be flushed down the toilet, but the agency has also declared a goal of working toward the return of all unused medicines.
■ The National Toxicology Program is conducting research to clarify how human health may be harmed by drugs at low environmental levels.
The Associated Press reported last year that the drinking water of at least 51 million Americans contains minute concentrations of a multitude of drugs. Water utilities, replying to a questionnaire, acknowledged the presence of antibiotics, sedatives, sex hormones, and dozens of other drugs in their supplies.
The news reports stirred congressional hearings and legislation, more water testing, and more disclosures of test results.
The EPA’s new study will look for 200 chemical and microbial contaminants at 50 plants that treat drinking water. The list includes 125 pharmaceuticals or related chemicals. This research will help federal officials decide whether regulations are needed.
In the first move toward possible drinking-water standards, the EPA has put 13 pharmaceuticals on what it calls the Contaminant Candidate List. They are mostly sex hormones, but include the antibiotic erythromycin. They join a list of 104 chemical and 12 microbial contaminants that the EPA is considering as candidates for regulation under the Safe Drinking Water Act. No pharmaceutical had been placed on the list in its 12-year history, but medicines now make up 13 percent of it.
They take a place beside such better-known contaminants as the metal cobalt, formaldehyde, the rocket fuel ingredient perchlorate, and the disease germ E. coli.
“I think this does signal a change in the regulatory and research approaches,’’ said Conrad Volz, a University of Pittsburgh scientist whose research raises questions about the risk of eating fish from waters contaminated with sex hormones. “What’s happening is pretty amazing.’’
