Are Our Medicines Tainting the Environment?
Daughton says some might ask: Aren't drug residues degradable? "Sure,
they might be," he says. "But you're constantly introducing them. So
these aquatic organisms are exposed 24 hours a day to these chemicals for their
entire life span."
And even very small amounts of some drugs might make a difference, experts
say. "The interesting thing about pharmaceuticals is that sewage treatment
plants don't do anything to remove them," says Bob Morris, MD, PhD, an
environmental epidemiologist and associate professor in the department of
family medicine and community health at Tufts University in Boston. "And
second, these are chemicals specially designed to have an effect on humans at
low levels -- and that's what makes this story interesting."
Among those chemicals are female hormones, found in birth control pills.
"The difference between a man and woman has to do with parts per trillion
of estradiol," Morris says. "These compounds have dramatic biological
effects at parts per trillion levels. So the concentrations we think aren't
worth worrying about may be worth worrying about."
One organization that apparently is not worried about drug pollution at this
time is the Pharmaceutical Research and Manufacturers of America (PhRMA).
"We know it's an emerging issue," says Meredith Art, media specialist
for the group. "We haven't seen any reports of drugs polluting the water in
the U.S. It's been mostly overseas from what we've read -- in Switzerland, the
U.K., and Germany. We really don't even know if these (pollutants) are
pharmaceuticals. It depends on how people are testing them."
But PhRMA could be seeing some U.S. results soon. Last year, the United
States Geological Survey (USGS) began testing for drug and household-product
residues in 100 streams it deemed "susceptible" to such contamination
-- ones located, for example, near animal feed lots or wastewater discharge
pipes. This year, the effort will be expanded to 25 more streams as well as
some ground wells.
"We are finding things," says Herb Buxton, coordinator for the USGS
Toxic Substances Hydrology Program in Trenton, N.J. "Some antibiotics, some
prescription drugs -- with a detection frequency up to 40%."