Drug residues contaminate drinking water supplies when people take pills. While their bodies absorb some of the medication, the rest is flushed down the toilet.
Drinking water treatment plants are not designed to remove these pharmaceutical residues, and the AP team uncovered data showing these same chemicals in treated tap water and water supplies in 24 major metropolitan areas.
All of the pharmaceuticals reported in drinking water supplies are unregulated in treated tap water. Although the concentrations of drugs found by the AP research were miniscule, measured in parts per billion, any level is legal and the U.S. Environmental Protection Agency, EPA, does not require water utilities to test for these substances.
Tap water can contain drugs and other contaminants. (Photo by Greg Riegler)
Previous research has shown that exposure to levels even lower than reported in this survey can cause harm to aquatic species. Effects on humans, if any, have not been determined.
The USGS survey revealed a list of compounds including the painkillers acetaminophen and ibuprofen, prescription medicines for cardiac disorders and hypertension, and female sex hormones used in birth control pills and hormone replacement therapy.
The AP study surfaced as a campaign to get consumers to use tap water instead of bottled water is being waged across the country by the nonprofit group Food & Water Watch.
"All our water sources - rivers and reservoirs, springs and aquifers - may contain drugs flushed down our toilets and off factory farms somewhere up stream," said Food & Water Watch Executive Director Wenona Hauter. "But scaring people away from their taps into the bottled water isle at the grocery store will cost them thousands of dollars a year without making them any safer."
"Nearly 40 percent of bottled water is simply repackaged tap water. What's more, there's no government agency testing bottled water contamination from known hazards such as bacteria, synthetic contaminants, or heavy metals," Hauter said.
"While the Associated Press did not test bottled water, earlier testers have found dangerous substances such as arsenic and bromate, both known carcinogens. And bottled water comes with its own list of unknown hazards from chemicals leached into the water from the plastic bottles. Hauter maintains, "Tap water is still the best choice for most Americans."
The AP research extends knowledge detailed in a survey of contaminants in tap water conducted by the nonprofit Environmental Working Group published in December 2005.
Tap water in 42 states is contaminated with more than 140 unregulated chemicals that lack safety standards, the Environmental Working Group found during a 30 month investigation of water suppliers' tests of the treated tap water.
"Environmental Working Group's studies show that tap water across the U.S. is contaminated and now we know that millions of Americans are also drinking low level mixtures of pharmaceuticals with every glass of water," said Jane Houlihan, Environmental Working Group vice president for research.
"The health effect of this cocktail of chemicals and drugs hasn't been studied but we are concerned about the effects on infants and others who are vulnerable, Houlihan said.
Environmental Working Group analysis shows that of the top 200 drugs in the United States, 13 percent list serious side effects at levels less than 100 parts per billion, ppb, in human blood, with some causing potential health risks in the parts-per-trillion range.
A national tap water atlas published online by the Environmental Working Group shows tap water testing results from 40,000 communities around the country. View the atlas at: http://www.ewg.org/sites/tapwater/
The drug residues in tap water join hundreds of other synthetic chemicals Americans are exposed to daily, as contaminants in food, water, and air, or in common consumer products.
The environmental groups are asking the U.S. Environmental Protection Agency to take swift action to set standards for pollutants in tap water that will protect the health of Americans nationwide, including children and others most vulnerable to health risks from these exposures.
Copyright Environment News Service (ENS) 2008. All rights reserved.