Drug traces found in water pose problem for wildlife
Date: Tuesday, October 18 2005
Drug traces found in water pose problem for wildlife pharmaceuticals passing unaltered from humans into nation's waterways
By Tom Pelton
October 16, 2005
Over the last two years, scientists working on the Potomac River have netted 111 smallmouth bass with bizarre sexual traits. The fish were males but had eggs growing inside their testes. Researchers found many of these gender-bending bass downstream from sewage treatment plants in water tinged with a chemical called ethinylestradiol - the active ingredient in birth control pills.
More studies are necessary, biologists say, but evidence is mounting that trace levels of prescription drugs in rivers and streams may be harming fish, tadpoles, frogs, mussels and oysters. The pharmaceuticals are passing unaltered through people's bodies and sewage plants into waterways.
In Georgia and Mississippi, scientists recently discovered that the antidepressant Prozac, in water downstream from sewage plants, can kill tadpoles, stunt the growth of others and befuddle the survivors so they swim in circles and can't flee from predators.
In Pennsylvania, a biologist reported that small amounts of Prozac may cause mussels and clams to discharge their sperm and eggs prematurely, dooming their offspring. And in Texas, a researcher found that the sexual organs of male minnows shrank when they were lowered into a river tainted with birth control drugs.
"We might just be seeing the tip of the iceberg in terms of the cumulative impact of all this," said Dr. Thomas Burke, associate chairman of health policy at the Johns Hopkins School of Public Health. Pollution concerns He said concerns about pharmaceutical pollution are likely to become more urgent as a growing human population consumes a multiplying number of medications.
"This is an important area we have to study more," Burke said.
The U.S. Environmental Protection Agency is working with other federal offices to investigate whether the government should require better sewage filtration systems to remove drugs before water is discharged, according to the agency. Pharmaceuticals are not regulated as pollutants, and most sewage plants are not designed to break them all down.
One stumbling block to adding better filtration systems is the cost, which could reach $100 million to install advanced technology on each large sewage treatment plant, said Shane Snyder, research manager at the Southern Nevada Water Authority.
[Proofreader's note: this article was edited for spelling and typos on October 19, 2005]