Pharmaceuticals in our water?

Duane Moser, an assistant research professor with Desert Research Institute, collects water samples from the Las Vegas Wash in Henderson, Nev., Thursday, Oct. 18, 2007. Photo courtesy of AP Photo/Jae C. Hong

But the presence of so many prescription drugs — and over-the-counter medicines like acetaminophen and ibuprofen — in so much of our drinking water is heightening worries among scientists of long-term consequences to human health. Water providers rarely disclose results of pharmaceutical screenings, unless pressed, the AP found. For example, the head of a group representing major California suppliers said the public “doesn’t know how to interpret the information” and might be unduly alarmed.

How do the drugs get into the water? People take pills. Their bodies absorb some of the medication, but the rest of it passes through and is flushed down the toilet. The wastewater is treated before it is discharged into reservoirs, rivers or lakes. Then, some of the water is cleansed again at drinking water treatment plants and piped to consumers. But most treatments do not remove all drug residue.

And while researchers do not yet understand the exact risks from decades of persistent exposure to random combinations of low levels of pharmaceuticals, recent studies — which have gone virtually unnoticed by the general public — have found alarming effects on human cells and wildlife.

Researchers at the U.S. Geological Survey analyzed a Passaic Valley Water Commission drinking water treatment plant, which serves 850,000 people in Northern New Jersey, and found a metabolized angina medicine and the mood-stabilizing carbamazepine in drinking water. A sex hormone was detected in San Francisco’s drinking water. The drinking water for Washington, D.C., and surrounding areas tested positive for six pharmaceuticals. Three medications, including an antibiotic, were found in drinking water supplied to Tucson, Ariz.

The situation is undoubtedly worse than suggested by the positive test results in the major population centers documented by the AP. The federal government doesn’t require any testing and hasn’t set safety limits for drugs in water. Of the 62 major water providers contacted, the drinking water for only 28 was tested. Among the 34 that haven’t: Houston, Chicago, Miami, Baltimore, Phoenix, Boston and New York City’s Department of Environmental Protection, which delivers water to 9 million people.

And while drugs are tested to be safe for humans, the timeframe is usually over a matter of months, not a lifetime. Pharmaceuticals also can produce side effects and interact with other drugs at normal medical doses. That’s why — aside from therapeutic doses of fluoride injected into potable water supplies — pharmaceuticals are prescribed to people who need them, not delivered to everyone in their drinking water.

Source: Associated Press