But health officials say the levels found in some drinking water are too low to cause harm.
According to a 2012 World Health Organization report, the “trace quantities of pharmaceuticals in drinking water are very unlikely to pose risks to human health.” The report said that the amount found in drinking water is usually 1,000 times lower than doses expected to have an effect on a person.
But Klaper said that in light of the gene changes in fish brains, officials may need to rethink what is considered safe.
“Fish do not metabolize drugs like we do,” Klaper said. “Even if environmental doses aren’t thought to be much for a human, fish could still have significant accumulation, and, it appears, changes in their brain’s gene expression.”
This article originally ran at Environmental Health News, a news source published by Environmental Health Sciences, a nonprofit media company.