April 16, 2008 -- A Bush administration official said the Environmental Protection Agency is "committed to taking action" on reports of pharmaceuticals in much of the nation's drinking water supply.
EPA top water official Benjamin Grumbles, fielding questions from lawmakers, said the prospect of drugs dissolved in drinking water was "troubling."
"We're very concerned about this information," Grumbles told the U.S. Senate Committee on Environment and Public Works. He said the agency has developed a draft list of drugs that it will consider for new limits under the Clean Drinking Water Act.
Only one prescription drug, nitroglycerin, is currently regulated under the act. But a report by the Associated Press last month found evidence of trace amounts of hundreds of drugs in drinking water consumed by up to 41 million U.S. residents.
The EPA's pledge to develop a draft list of drugs for testing did not impress the panel's Democrats. Sen. Barbara Boxer (D-Calif.), the committee's chairwoman, said a 2002 court order already compelled the EPA to compile a list of drugs that could disrupt hormone functioning in humans.
"Six years behind schedule," Boxer said. "This all means that pharmaceuticals in our water may have a disproportionate effect on pregnant women and children."
Grumbles said the agency is "not alarmed in terms of a risk to human health" from consuming water tainted with pharmaceuticals. He said "lots of pharmaceuticals" are found in drinking water but that they are in trace amounts.
But Robert Hirsch, associate director for water at the U.S. Geological Survey, said there was no way to be sure if long-term exposure to even trace amounts of drugs in water was harmful.
"The potential human health effects of low-level pharmaceuticals are not well understood and they warrant further study," Hirsch said.
Drugs are thought to enter the water supply mostly after being excreted by humans and flowing through sewer systems. Some are also introduced when they are discarded down toilets or sinks.
Grumbles said his agency discourages flushing unused drugs down toilets. Instead, drugs should be mixed with kitty litter or coffee grounds and thrown in the trash, he said. The White House Office of National Drug Control Policy recommends on its web site that only controlled substances, such as OxyContin, be flushed down the toilet.
Boxer criticized the agency for proposing to cut by 35% its budget for testing water for hormone-disrupting agents.