An Associate Press-led investigation showed that water used by about 41 million Americans contains a mixture of pharmaceuticals, ranging from antibiotics, anti-convulsants, mood stabilizers and sex hormones.
The concentration of the pharmaceuticals is below the levels of a medical dose, but their presence increases worries among scientists, who said the exposure to random combinations of low levels of pharmaceuticals could have very bad long-term consequences on the heath of the people who drink it.
The AP investigation discovered that the drinking water supplies of 24 of 28 major metropolitan areas tested from Southern California to Northern New Jersey, from Detroit to Louisville, Kentucky contain drugs.
Utilities insist their water is safe. However, water providers are very reluctant when it comes to disclosing the results of pharmaceutical screenings.
We recognize it is a growing concern and we're taking it very seriously, said Benjamin H. Grumbles, assistant administrator for water at the U.S. Environmental Protection Agency.
The drugs have ended up in the water through a variety of ways Pills taken by people are not wholly absorbed, and some is passed through and flushed down the toilets. Sewage treatment plants don't remove the drugs. The treated water then flows into lakes, rivers and reservoirs, and finally to drinking water plants, which usually don't screen for drugs.
Testing is not required by the federal government, which does not have any set safety limits for drugs in water.
Scientists said they are seeing effects on animals with some male fish, for example, have developed female traits and have reproductive problems. Scientists believe the cause may be exposure to human birth control hormones.