March 10, 2008

America’s Drinking Water Full of Drugs

A five-month Associated Press (AP) investigation found that drinking water supplies for at least 41 million Americans are contaminated with a variety of pharmaceuticals, including sex hormones, antibiotics, mood stabilizers, anti-convulsants and even some over-the-counter medicines such as acetaminophen and ibuprofen.

The report said that concentrations of these pharmaceuticals, measured in parts per billion or trillion, are far below the levels of a medical dose. But the presence of prescription and over-the-counter drugs in our drinking water is alarming to some scientists who worry about the long-term ramifications to public health.

For their part, the utility companies are insisting their water supplies are safe.

During their investigation, the AP discovered that drugs have been detected in drinking water supplies of 24 major metropolitan areas. The investigative team said the water providers rarely disclose results of pharmaceutical screenings unless pressed. For example, the head of a group representing major California suppliers said the public "doesn't know how to interpret the information" and might be unduly alarmed, the team reported.

The pharmaceuticals find their way into the water supply through a series of events, beginning with people who take these medications. While their bodies absorb some of the medication, the rest passes through and is flushed down the toilet. Although the wastewater is treated before it is discharged into reservoirs, rivers or lakes, and some of the water is cleansed again at drinking water treatment plants, most treatments do not remove the entire drug residue.

Scientists do not yet fully understand the precise risks from decades of persistent exposure to random combinations of low levels of these pharmaceuticals, recent studies have found alarming effects on both humans and wildlife.

"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 (EPA), according to the AP report of the inquiry.

Members of the AP National Investigative Team surveyed the country's 50 largest cities along with 12 other major water providers, and also examined smaller community water providers within all 50 states. They reviewed hundreds of scientific reports, analyzed federal drinking water databases, visited environmental study sites and treatment plants and interviewed more than 230 officials, academics and scientists.

The following are some of the results reported by the AP after their analysis:

  • In Philadelphia, officials discovered 56 pharmaceuticals or byproducts in treated drinking water, including medicines for pain, infection, high cholesterol, asthma, epilepsy, mental illness and heart problems. 63 pharmaceuticals or byproducts were found in the city's watersheds.
  • In Southern California, anti-epileptic and anti-anxiety medications were detected in a portion of the treated drinking water for 18.5 million people.
  • Researchers at the U.S. Geological Survey (USGS) analyzed a Passaic Valley Water Commission drinking water treatment plant serving 850,000 people in Northern New Jersey, and discovered a metabolized angina medicine and the mood-stabilizing carbamazepine in the drinking water.
  • A sex hormone was detected in San Francisco's drinking water.
  • Washington, D.C.'s drinking water tested positive for six pharmaceuticals.
  • In Tucson, AZ, water was found to have three medications, including an antibiotic.

Since the federal government doesn't require any testing and has not set safety limits for concentrations of drugs in water, the situation is likely worse than suggested by the positive test results in the major population centers.

In fact, of the 62 major water providers contacted, only 28 were even tested. Included in the 34 that were not tested are Houston, Chicago, Miami, Baltimore, Phoenix, Boston and New York City's Department of Environmental Protection, which delivers water to 9 million people.

Some providers only test for one or two pharmaceuticals, leaving open the possibility that others are present but go undetected.

The AP's investigation found that watersheds, the natural sources of most of the nation's water supply, are also contaminated. Tests of watersheds in 35 of the 62 major providers surveyed detected pharmaceuticals in 28. Yet officials in six of those 28 metropolitan areas, which include Fairfax, Va., Montgomery County, MD., Omaha, NE., Oklahoma City; Santa Clara, CA., and New York City, said they did not go on to test their drinking water.

The New York state health department and the USGS tested the source of the city's water upstate, and found trace concentrations of heart medicine, infection fighters, estrogen, anti-convulsants, a mood stabilizer and a tranquilizer.

The AP report said city water officials declined repeated requests for an interview. However, in a statement officials insisted that "New York City's drinking water continues to meet all federal and state regulations regarding drinking water quality in the watershed and the distribution system", regulations that do not address trace pharmaceuticals.

In several cases, officials at municipal or regional water providers told the AP that pharmaceuticals had not been detected, but the AP obtained the results of tests conducted by independent researchers that showed differently. For instance, officials with the New Orleans water department said their water had not been tested for pharmaceuticals, but a Tulane University researcher and his students had published a study showing the pain reliever naproxen, the sex hormone estrone and the anti-cholesterol drug byproduct clofibric acid were present in treated drinking water.

Of the 28 major metropolitan areas where tests were performed on drinking water supplies, only Austin, TX, Virginia Beach, VA, and Albuquerque, NM, reported negative results. Officials in Dallas are awaiting test results, but Arlington, Texas, acknowledged that traces of a pharmaceutical were detected in its drinking water. They cited post-9/11 security concerns in refusing to identify the drug.

During their investigation, the AP also contacted 52 small water providers, one in each state and two each in Missouri and Texas, which serve communities with approximately 25,000 people. All but one said their drinking water had not been screened for pharmaceuticals. Providers in Emporia, KS., declined to answer AP's questions, citing post-9/11 security concerns.

Experts say consumers in rural area who draw water from their own wells cannot necessarily be sure their water is free from contamination.

The Stroud Water Research Center in Avondale, PA., measured water samples from New York City's watershed upstate for caffeine, a common test that could also suggest the presence of other pharmaceuticals. Though less caffeine was detected there than at suburban sites, researcher Anthony Aufdenkampe was surprised by the relatively high levels the tests revealed.

He believes it could be escaping from failed septic tanks, maybe with other drugs. "Septic systems are essentially small treatment plants that are essentially unmanaged and therefore tend to fail," Aufdenkampe said.

Even those who drink bottled water or utilize home filtration systems are not necessarily guaranteed their water is free from pharmaceutical contaminants.

The AP report quoted the industry's main trade group as saying that some bottled water manufacturers simply repackage tap water and do not test or treat for pharmaceuticals. The same holds true for makers of home filtration systems.

Outside the United States, studies have detected more than 100 unique pharmaceuticals in lakes, rivers, reservoirs and streams throughout Asia, Australia, Canada and Europe, and even in Swiss lakes and the North Sea.

In Canada, a study by a national research institute found 9 pharmaceuticals in water samples from 20 different water treatment plants. In December, after detecting prescription drugs in drinking water at seven sites, Japanese health authorities called for human health impact studies.

In the United States, pharmaceuticals have also been found to permeate aquifers deep underground, the source of 40 percent of the nation's water supply. Federal researchers drew water from aquifers near contaminant sources such as landfills and animal feed lots in 24 states and found minute levels of hormones, antibiotics and other drugs.

The AP suggested that the problem might be due to Americans taking drugs, and flushing them unmetabolized or unused, in growing amounts. According to IMS Health and The Nielsen Co., the number of U.S. prescriptions rose 12 percent to a record 3.7 billion over the past five years, while nonprescription drug purchases held steady around 3.3 billion.

"People think that if they take a medication, their body absorbs it and it disappears, but of course that's not the case," said EPA scientist Christian Daughton, one of the first to draw attention to the issue of pharmaceuticals in water in the United States, according to the Associated Press report.

Some drugs are even resistant to modern drinking water and wastewater treatment processes, including the popular cholesterol fighters, tranquilizers and anti-epileptic medications. Additionally, the EPA says there are no sewage treatment systems specifically engineered to remove pharmaceuticals.

However, one technology, reverse osmosis, effectively removes all pharmaceutical contaminants. But is extremely costly for large-scale use and leaves several gallons of polluted water for every one that is made drinkable.

Further complicating the issue, there's evidence that adding chlorine, a common process in conventional drinking water treatment plants, makes some drugs even more toxic.

The Associated Press report said animals are also contributing to the problem. For instance, cattle are given ear implants that slowly release the anabolic steroid trenbolone that causes them to bulk up. However, not all the trenbolone circulating in a steer is metabolized, and a German study found that 10 percent of the steroid passed right through the animals.

Another study found samples of water downstream of a Nebraska feedlot contained steroid levels four times as high as the water taken upstream. The research also showed that the male fathead minnows living in the downstream area had small heads and low testosterone levels.

Other veterinary drugs also contribute to the problem. For example, pets are now routinely diagnosed and treated for conditions such as arthritis, cancer, heart disease, diabetes, allergies, dementia, and even obesity. Often, these pets receive the same drugs as humans for these illnesses. And as with humans, the amount of pharmaceuticals given to pets is also on the rise. An analysis of data from the Animal Health Institute found the inflation-adjusted value of veterinary drugs had risen 8 percent, to $5.2 billion, over the past five years.

The AP investigative team sought the pharmaceutical industry's perspective about the contaminated water, and received a mixed response.

"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," said microbiologist Thomas White, a consultant for the Pharmaceutical Research and Manufacturers of America, according to AP's report.

But at a conference last summer, Mary Buzby, director of environmental technology for drug maker 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 causing impacts to human health or to aquatic organisms."

Studies support the concern. Recent laboratory research has shown that small amounts of pharmaceuticals affect human embryonic kidney cells, human blood cells and human breast cancer cells. The research found the kidney cells grew too slowly, the cancer cells proliferated too quickly, and the blood cells showed inflammatory biological activity.

In addition to the impact on humans, the AP report outlined some of the effects the contaminated water is having on wildlife. Pharmaceuticals present in waterways are damaging wildlife worldwide. For instance, male fish are being feminized, creating egg yolk proteins, a process usually restricted to females. Furthermore, studies show pharmaceuticals are affecting sentinel species at the foundation of the pyramid of life, such as earth worms in the wild and zooplankton in the laboratory, although scientists stress the research is extremely limited with many unknowns. However, they add that the documented health problems in wildlife are troubling.

"It brings a question to people's minds that if the fish were affected ... might there be a potential problem for humans?" EPA research biologist Vickie Wilson told the AP. "It could be that the fish are just exquisitely sensitive because of their physiology or something. We haven't gotten far enough along."

Shane Snyder, a research and development project manager at the Southern Nevada Water Authority, said greater emphasis should be placed on studying the effects of the contaminated water.

"I think it's a shame that so much money is going into monitoring to figure out if these things are out there, and so little is being spent on human health," he said. "They need to just accept that these things are everywhere - every chemical and pharmaceutical could be there. It's time for the EPA to step up to the plate and make a statement about the need to study effects, both human and environmental."

For now, the EPA seems focused on detection. Grumbles acknowledged that just late last year the agency developed three new methods to "detect and quantify pharmaceuticals" in wastewater.

"We realize that we have a limited amount of data on the concentrations," he said. "We're going to be able to learn a lot more."

Grumbles said the EPA had analyzed 287 pharmaceuticals for possible inclusion on a draft list of candidates for regulation under the Safe Drinking Water Act. However, he said only nitroglycerin, used to treat heart problems, was on the list. It is primarily being considered due to the drug's widespread use in making explosives.

Much remains to be learned as experts study the effects of the contaminated water. Many independent scientists do not believe trace concentrations of pharmaceuticals will ultimately prove to be harmful, however this confidence is based largely on studies that poison lab animals with much higher amounts. Meanwhile, the scientific community is increasingly concerned that certain drugs, or combinations of drugs, could harm humans over long periods of time because water is consumed consistently and in sizeable amounts every day.

Whereas the human body may be capable of shrugging off a one-time large dose, it may react negatively from smaller amounts delivered continuously over decades. Pregnant women, the severely ill and the elderly could perhaps be even more sensitive to the effects.

Many concerns about chronic low-level exposure are centered around certain drugs, for instance chemotherapy agents that can act as a poison, hormones that can hamper reproduction or development, depression and epilepsy medications that can damage the brain or alter behavior, antibiotics that can cause germs to mutate into more dangerous drug-resistant forms, and pain relievers and blood-pressure diuretics.

For decades nonprofit watchdog groups and federal environmental officials have focused on regulated contaminants such as pesticides, lead, and PCBs, which are known to be present in water and pose a clear health risk to humans and animals. However, some experts say medications may pose a unique danger because they were actually designed to act on the human body, unlike most pollutants.

"These are chemicals that are designed to have very specific effects at very low concentrations. That's what pharmaceuticals do. So when they get out to the environment, it should not be a shock to people that they have effects," says John Sumpter, a zoologist at Brunel University in London, who has studied trace hormones, heart medicine and other drugs.

While some drugs have passed safety tests for human exposure, the timeframe is usually over a matter of months, not over decades or entire lifetimes. And pharmaceuticals can create side effects and interact with other drugs at normal medical doses, a reason why these drugs are prescribed only to those who need them.

"We know we are being exposed to other people's drugs through our drinking water, and that can't be good," says Dr. David Carpenter, director of the Institute for Health and the Environment of the State University of New York at Albany.


On the Net:

U.S. Environmental Protection Agency (EPA)

USGS Water Resources of the United States

Stroud Water Research Center

"The fate of trenbolone acetate and melengestrol acetate after application as growth promoters in cattle: environmental studies"

Pharmaceutical Research and Manufacturers of America