DRUGS IN THE DRINKING WATER: STATES WEIGH WHETHER TO ACT

Volume 29, Issue 513 April 14, 2008

Anna Wolke

For decades, Americans have followed the common-sense advice to flush unused drugs down the toilet. Now, the experts who dished out that advice are rethinking their prescription. Studies are revealing that a wide array of pharmaceuticals has trickled into the surface and ground waters that feed our nation’s water supply:

in 1999, the U.S. Geological Survey began sampling 139 streams around the country and in 2002, reported that 80 percent of the samples contained some type of pharmaceutical compound;
another investigation (see below) concluded that 24 out of 62 water systems in major metropolitan areas contained traces of medications such as antibiotics and steroids;
and in 2006, water quality researchers discovered evidence that natural and synthetic sex steroids are causing some male fish to produce immature eggs.

Sewage treatment plants are not equipped to remove drug traces from the water, and drinking water plants are not required to monitor the levels of most drugs in the water. Federal law mandates that only one drug—nitroglycerin—be monitored. One process, reverse osmosis, removes most pharmaceutical residue from the water, but is more costly than conventional treatment methods. A few municipal water systems have implemented reverse osmosis.

Some scientists say that drug residues have been in the water for a long time, but are only now being detected because the testing technology is more sensitive. Some researchers also say that the trace levels found are too low to have an effect on humans. But other scientists are concerned, and their apprehensions are galvanizing some states to pass laws to prevent or reduce contamination.

How Did They Get There?

There are several avenues through which traces of drugs can end up in our water supply. Some drug residues turn up because our bodies do not completely metabolize the drugs we ingest. Eventually, small quantities of our medications are naturally excreted and make their way, unfiltered by water treatment, into our sewer systems and water supplies.

Consumer habits for discarding medications also contribute to water contamination. For years, the public was instructed to flush their unused or expired prescriptions down the toilet to prevent the drugs from being abused or accidentally ingested. However, flushing drugs can lead to the contamination of surface and ground waters.

In an effort to correct this long-standing consumer practice, the White House Office of National Drug Policy issued guidance in February 2007 on the proper disposal of prescription drugs. The document instructs individuals to dispose of their extra or expired drugs in the trash, and suggests that medications be mixed with cat litter or coffee grounds and placed in an impermeable container or bag for disposal. The report also encourages consumers to take advantage of “take-back” programs—efforts sponsored by states or localities that collect consumers' drugs in a central location for proper disposal.

Livestock feedlots are another source of water contamination. Animals commonly receive drugs such as steroids to increase animal bulk, and antibiotics to prevent infections among closely quartered animals. Some waters downstream of feedlots have been found to contain higher concentrations of pharmaceuticals than upstream waters. It is feared that antibiotic residue originating from feedlots (and households) could contribute to the growing antibiotic-resistance of certain bacteria, such as methicillin-resistant staphylococcus, or MRSA.

Hospitals and long-term care facilities typically incinerate their unused medications—the ideal method for disposing of drugs.

State Actions

States are addressing drug residues in a variety of ways. According to the Illinois-Indiana Sea Grant program, part of a federal grant program that focuses on water quality, at least nine states have considered or passed bills to establish study commissions or require manufacturers to take more responsibility for the life of their products.

In 2003, Maine charted a different path by enacting Public Law, 2002, Chapter 679. The Unused Pharmaceutical Disposal Program called for the safe disposal of unused drugs, but was never funded. In 2007, the Legislature passed legislation that will fund the program through a one-time grant from the Environmental Protection Agency (EPA). Consumers will be given pre-paid mailers when they purchase their prescription drugs so that any leftover pills may be securely mailed to the Maine Drug Enforcement Agency for incineration. "Where all of those drugs end up (is) a very important issue," said bill sponsor Representative Anne Perry.

States are increasingly looking to drug manufacturers to foot the cost of reducing pharmaceutical contamination, according to Scott Cassel, director of the Product Stewardship Institute. "Producer responsibility requires the manufacturer to take care of the entire life of their product,” he said. “This does not necessarily mean pharmaceutical manufacturers take back their products [at the end of life], but that they help fund the take-back programs set up by state or local governments."

The Institute’s Pharmaceuticals Project facilitates negotiations and collaborations to deal with household and health-care facility pharmaceutical waste. Currently, the Institute is working with 43 member states on the issue.

In California, Assemblymember Joseph Coto introduced a bill (AB 2425) during the 2008 session that would require drug manufacturers whose products have been detected in the state water supply to file a report with the State Public Health Officer. The report would include an analysis of how the drugs entered the water supply and recommend methods to prevent or remove the residues.

"Pharmaceuticals are manufactured to be taken by the individual who needs them and not by everyone in the state by means of the drinking water," said Assemblymember Coto. Drug manufacturers "possess knowledge of specific chemicals and are in a good position to help address the health hazard posed by the pharmaceuticals in drinking water throughout the state."

In 2007, Governor Arnold Schwarzenegger signed SB 966, which requires the state's Integrated Waste Management Board to develop model programs to ensure the safe take-back or proper disposal of unused pharmaceuticals. Once developed, the state plans to put take-back programs in place in clinics, pharmacies and other medical facilities.

Washington also has legislation (HB 2600) pending this session that would require drug manufacturers to manage and fund programs to collect and dispose of prescription and non-prescription household drugs at no cost to the consumer.

While states weigh whether to act, scientists debate. "Based on what we now know, I would say we find there's little or no risk from pharmaceuticals in the environment to human health," microbiologist Thomas White told the Associated Press.

Some feel, however, that there is reason to act. Mary Buzby, director of environmental technology for Merck & Co., said, "There's no doubt about it, pharmaceuticals are being detected in the environment and there is genuine concern that these compounds, in the small concentrations that they're at, could be [affecting] human health or aquatic organisms."

MAJOR METRO AREAS FOUND TO HAVE RESIDUES IN DRINKING WATER

In 2007-2008, the Associated Press conducted a five-month long investigation looking into pharmaceutical contamination of the nation's drinking water. The investigation found that 28 out of 35 watersheds contained drug traces. The type and number of drugs varied by city; tests of Philadelphia's drinking water, for example, turned up 56 different pharmaceutical ingredients or byproducts.

Among the drugs detected were painkillers, antibiotics and steroids, as well as ingredients from cholesterol medication, anti-depressants, blood pressure medication, epilepsy medication and birth control pills. While the levels of drugs found in the water were minimal, the long-term risks of unintentional exposure to trace levels and combinations of drugs are largely unknown.

One main concern, according to the EPA, is the risk posed by natural and synthetic sex steroids on the endocrine systems of fish. In 2006, water quality researchers discovered evidence that natural and synthetic sex steroids are affecting the endocrine systems of fish. In a tributary of the Potomac River (which flows through four states and the District of Columbia), researchers found "intersex" fish—male fish carrying immature eggs. Over the past decade, numerous studies have found similar reproductive abnormalities in other aquatic animals and suggested a link to the presence of man-made compounds in the water.

While some water providers test the levels of certain pharmaceuticals in their water, the results are typically not released because of the lack of federal standards. The EPA has set standards for 90 chemical, microbiological, radiological, and physical contaminants, but only one type of pharmaceutical drug—nitroglycerin—is monitored, as mandated by the Safe Drinking Water Act.

Benjamin H. Grumbles, assistant administrator for water at the EPA, told the Associated Press that the federal government has some catching-up to do and said the agency plans to research and analyze the issue further. "We recognize it is a growing concern and we're taking it very seriously," he said.