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Vol. 13 Issue 2, Spring 2008
By Carmi Orenstein, M.P.H., Ribbon Editor and BCERF Assistant Director
Many Ribbon readers may have seen the three-part Associated Press (AP) story on pharmaceuticals in US drinking water that appeared in newspapers around the country this spring. The articles reported on AP’s five-month inquiry into the drinking water of 62 metropolitan areas and 51 smaller cities. They found that the drinking water of at least 24 American cities contains trace amounts of a wide array of pharmaceuticals and their by-products. These include antibiotics, heart medications, psychiatric drugs, hormones such as those in birth control pills, and others.
Municipal drinking water supplies are extensively regulated by the US Environmental Protection Agency (EPA), which sets limits on certain contaminants (see: http://www.epa.gov/safewater/contaminants), but there are no federal regulations handed down that include pharmaceuticals. The 24 cities that detected pharmaceuticals through voluntary testing efforts are under no obligation to report them, nor treat for them. About half the water utilities surveyed do not test for pharmaceuticals. The majority that do test found some of these trace amounts.
With regard to bottled water, the AP story states, “bottlers, some of which simply repackage tap water, do not typically treat or test for pharmaceuticals, according to the industry's main trade group.”
Understanding the implications of exposure to trace amounts of pharmaceuticals
The authors state that new developments in analytic chemistry are what allows the detection of these small amounts, which are sometimes even measured as parts per trillion. Some point to the fact that these levels are minute in order to allay potential fears about exposure to pharmaceuticals from these sources. But as emerging evidence shows, for example, with hormone-disrupting chemicals, we do not know the lower threshold of effects, nor do we have a full understanding of implications for vulnerable populations or the consequences of exposure to chemical mixtures. And, as the AP author Jeff Donn underscores as a key consideration in choosing to examine pharmaceuticals in particular as contaminants, these are substances designed to interact with the body. He points to an emerging body of scientific research in which human cells in a laboratory setting are demonstrating responses to mixtures of drugs at levels found in water systems (Pomati, F., et al (2008), Effects and interactions in an environmentally relevant mixture of pharmaceuticals, Toxicological Sciences 102, 129-37). There is already a substantial body of evidence of adverse effects of endocrine-disrupting compounds, such as those in some pharmaceuticals, in wildlife populations; for example, the feminization of fish by ethinyl estradiol, present in oral contraceptive pills.
Many pathways may lead to pharmaceuticals in drinking water supplies
Pharmaceuticals enter wastewater systems in a number of ways. Once individuals have ingested them, a portion of the substance passes through the body and enters the sewage stream. Both metabolized and unmetabolized substances are excreted.
Unused medicines are often directly disposed of by flushing. This was, and in some places remains, the directive the public typically receives for disposal. The Pharmaceutical Research and Manufacturers of America states that about one-third of unused medicines are generated by long-term care facilities, which have typically relied on flushing as their primary disposal method. (This organization has entered into a collaborative effort to change this practice, described below.)
Processes in wastewater treatment may alter the chemicals, depending on the chemical itself and the form of treatment. There are no regulations that specifically require treatment of pharmaceuticals. It is not known exactly how any of the detected pharmaceuticals enter drinking water supplies from wastewater, but wastewater treatment plants are commonly found upstream from drinking water intakes. Drinking water treatment, which is effective in treating microorganisms, is not designed to remove pharmaceuticals, and it is not known what effects it does have on pharmaceuticals.
Animal husbandry contributes to the pharmaceutical load in the environment. A percentage of the antibiotics used in large animal feeding operations are excreted and can persist in the soil and enter groundwater. Anabolic steroids are commonly used in feedlots, and have been shown to have breakdown products that have endocrine-disrupting effects in fish.
There have been a variety of previous and ongoing studies on human and veterinary drugs finding their way into water systems. The US Geological Survey’s Toxic Substance Hydrology Program has reported for a decade on these issues. See for example:
Pharmaceuticals, Hormones, and Other Organic Wastewater Contaminants in U.S. Streams http://toxics.usgs.gov/highlights/DM_top100.html
Veterinary Medicines in the Environment http://toxics.usgs.gov/highlights/vet_meds.html
Education and policy addressing pharmaceuticals in the environment
Around the US, there has been increased activity recently on the part of various agencies and organizations addressing pharmaceuticals in the environment, some of which is highlighted below.
There is increased examination of the sheer amount of pharmaceutical susbtances entering the waste stream. A recent study by Medco Health Solutions, Inc., which manages prescription benefits for one in five Americans, showed that for the first time, in 2007 more than half of insured Americans take prescription medicines for chronic health problems. The report noted that the largest increase in use of medications was in the 20- to 44-year-old age group and involved medications for depression, diabetes, asthma, attention deficit disorder and seizures. They also cited children’s rising use of medicines to treat weight-related problems. Pharmaceuticals detected in water systems seem to be another society-wide challenge that stands to benefit from a strategy of primary prevention of chronic disease.
SMARxT DISPOSAL. On March 17, 2008 the Pharmaceutical Research and Manufacturers of America signed an agreement with the US Fish and Wildlife Service and the American Pharmacists Association to “help protect the nation’s fish and aquatic resources from the improper disposal of medication.” The campaign is called SMARxT DISPOSAL, and emphasizes the disposal of medications in the trash as opposed to flushing them. See http://www.smarxtdisposal.net/
Senate Hearings. On April 15, 2008 the US Senate Committee on Environment and Public Works held hearings entitled, “Pharmaceuticals in the Nation’s Water: Assessing Potential Risks and Actions to Address the Issue.” Senator Barbara Boxer, Chair of the Committee, praised the AP and the US Geological Survey (USGS) in her opening remarks, but was particularly critical of the federal agencies and the US Environmental Protection Agency (EPA) in doing “very little” to address this issue (see box on the Natural Resources Defense Council’s recommendations to EPA and Congress). The hearings include testimony by:
Natural Resources Defense Council Recommendations to EPA and the US Congress Excerpted from testimony of Jennifer Sass, Ph.D. to the US Senate Committee on Environment and Public Works on April 15, 2008
Under the Safe Drinking Water Act and the Food Quality Protection Act, EPA has the authority and obligation to ensure the safety of our drinking water. EPA should:
Congress needs to take additional steps to help address this issue, including:
A version of Jennifer Sass’s testimony will appear in a coming issue of the International Journal of Occupational and Environmental Health
States’ attention to the issue of disposal of pharmaceuticals. Many states have introduced or passed legislation initiating a coordinated approach to the problem of disposing unwanted pharmaceuticals. These may include community solid waste programs accepting pharmaceuticals on a single-day or continuous basis, and/or pharmacy take-back programs. (These types of programs are common outside of the US: drop-off of unwanted pharmaceuticals at pharmacies exists in parts of Canada, in Australia, and in eleven European Union nations.) California recently passed legislation that creates model disposal programs and requires the California Integrated Waste Management Board to report back to the legislature on their progress on statewide implementation. There are a variety of collection projects being tried in various regions around the country.
For example, Alachua County in Florida ran a pilot project for “continuous collection system for pharmaceutical wastes” and documented their results in detail that could help other such trials. They found “programs could succeed by endeavoring to include convenient, public locations to increase participation;” they found that “the addition of larger chain pharmacy locations enhances the number of participants and allows greater flexibility for customers when dropping off pharmaceutical waste;” and “future flexibility may include mail-in programs with envelopes for return of unused medications to manufacturers or collection centers.” (http://www.entrepreneur.com/trade
journals/article/
166778956_1.html)
In Maine, the EPA and the state are sharing cost of a four-county trial, as the first step in implementing the Maine Unused Pharmaceutical Disposal Project, adopted by the state legislature in 2004. This pilot project involves postage-paid mailers available to the public through participating pharmacies. It includes an inventory of the types and quantities of drugs being returned, which could be used by the medical community to change prescription practices in an effort to reduce the amount of unused medications in people's homes.
Here in New York State, the Department of Environmental Conservation (DEC) facilitated a roundtable discussion meeting on May 15, 2008 to explore issues such as current pharmaceutical disposal practices, federal and state regulations, transporting of pharmaceuticals, and policy and programmatic options for proper waste management. The New York State Department of Health (DOH), which partnered with the DEC to host this roundtable discussion, has been investigating potential pharmaceutical contamination since the 1990s and plans to work with the health care industry on disposal issues. The goal for the discussion was for DEC and DOH staff and outside experts to exchange information on pharmaceutical waste issues, implications for the environment and public health, research needs and data gaps, and to identify possible policy solutions. Also in New York State there are related bills under consideration, sponsored by Assemblyman Steve Englebright and Senator Jim Alesi, which put forth a number of pharmaceutical disposal-related requirements on the part of drug manufacturers, consumers, the DEC, and pharmacies and other retailers. See: http://assembly.state.ny.us/leg/?bn=a+840 and/or http://www.assembly.state.ny.us/leg/?bn=S07560&sh=t
Even as research continues on health effects of our environmental exposures to chemicals including pharmaceuticals, as policymaking confronts this particular source of potential environmental contamination, and as advanced water treatment technologies become more routine, the public will inevitably have a large role to play in the way we handle and dispose of our medications.
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