Drugs in Our Drinking Water?
Experts put potential risks in perspective after a report that drugs are in the water supply.
Tiny amounts of pharmaceuticals -- including antibiotics, hormones, mood
stabilizers, and other drugs -- are in our drinking
water supplies, according to a media report.
In an investigation by the Associated Press, drinking water supplies in 24
major metropolitan areas were found to include drugs.
According to the investigation, the drugs get into the drinking water supply
through several routes: some people flush unneeded medication down toilets;
other medicine gets into the water supply after people take medication, absorb
some, and pass the rest out in urine or feces. Some pharmaceuticals remain even
after wastewater treatments and cleansing by water treatment plants, the
Although levels are low -- reportedly measured in parts per billion or
trillion -- and utility companies contend the water is safe, experts from
private organizations and the government say they can't say for sure whether
the levels of drugs in drinking water are low enough to discount harmful health
WebMD asked experts to give their take on the potential risks of drugs in
the water supply.
Is this a new phenomenon, the finding of pharmaceuticals in public water supplies?
No. Low levels of pharmaceuticals in the water supply have been a concern
for a decade or longer, says Sarah Janssen, MD, PHD, MPH, a science fellow at
the Natural Resources Defense Council, an environmental action group.
"Ever since the late 1990s, the science community has recognized that
pharmaceuticals, especially oral contraceptives, are found in
sewage water and are potentially contaminating drinking water," Janssen
Concern among scientists increased when fish in the Potomac River and
elsewhere were found to have both male and female characteristics when exposed
to estrogen-like substances, she says. For instance, some fish had both testes
and an ovary, she says.
Scientists starting looking at the effects of oral contraceptives first, she
says. "Now analyses have expanded to look at other drugs," Janssen
Technology has made this research easier, says Suzanne Rudzinski, deputy
director for science and technology in the Office of Water at the U.S.
Environmental Protection Agency. "Analytical methods have gotten better and
we are able to detect lower levels than ever before."
Is there a health effect of drugs in drinking water?
All sides of the debate agree this is not known for sure. "At this point
we don't have evidence of a health effect," Rudzinski says, "although
it's an area of concern and one we will continue to look at."
Janssen agrees: "We don't know. It's true that the levels [of the
medications found in drinking water] are very low. But especially when it comes
to pharmaceuticals that are synthetic hormones, there is concern, because
hormones work at very low concentrations in the human body."
"We don't want people to be alarmed and think they can't drink their tap
water or that they shouldn't be drinking water," Janssen says. "We
think this report in particular is a call for our federal agencies -- EPA in
particular -- to do further studies to see what the health effects
EPA's ongoing research is focusing on the effect of pharmaceuticals in the
water supply on aquatic life and human health, Rudzinski says. But she could
not supply details of how much money is being allocated to that research effort
or when to expect answers.