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This news story originally provided by The Washington Post
Pollution Suspected Cause of Anomaly in River's South Branch
By David A. Fahrenthold
Washington Post Staff Writer
MOOREFIELD, W.Va. -- The South Branch of the Potomac River is as
clear as bottled water here, where it rolls over a bed of smooth
stones about 230 miles upstream from Washington. But there is a
mystery beneath this glassy surface.
Many of the river's male bass are producing eggs.
Scientists believe this inversion of nature is being caused by
pollution in the water. But they say the exact culprit is still
unknown: It might be chicken estrogen left over in poultry manure,
or perhaps human hormones dumped in the river with processed sewage.
Chances are, it is not something that federal and state inspectors
regularly test for in local waters.
The discovery has made the South Branch the latest example of an
emerging national problem: Hormones, drugs and other man-made
pollutants appear to be interfering with the chemical signals that
make fish grow and reproduce.
While researchers look for answers in West Virginia, other
scientists are testing Rock Creek, and another group is seeking
financial support to test the rest of the Potomac to see whether
they can find the same troubling effects downstream.
"Whatever's doing this to the fish may be the canary in the
mineshaft," said Margaret Janes, a West Virginia activist with
the Appalachian Center for the Economy and the Environment.
Scientists say it's still too early to tell what these findings
will mean for the bass population in the South Branch; they aren't
sure whether the affected males are still able to reproduce. And no
one is aware of any effects on human health in the Potomac
watershed.
But scientists believe that fish might be the first to absorb any
dangerous chemicals that might later affect humans.
"They're likely to be hit first," said Mike Focazio, a
researcher with the U.S. Geological Survey. "We look there, and
it seems to be happening."
The situation in West Virginia was discovered by accident, when
scientists from the state and the geological survey were called in
to investigate reports that fish in the South Branch were developing
lesions and dying en masse.
They dissected dozens of bass caught last summer, mainly
smallmouth bass. They found no obvious cause for the lesions or
deaths, but did discover that 42 percent of the male bass had
developed eggs inside their sex organs.
The study surprised scientists. Though the South Branch has been
cited for problems with bacteria from poultry manure, state
officials said it did well on most aspects of water-quality testing.
"We always have, and still do, look at this as one of our
highest-quality fisheries," said Patrick Campbell of the state
Department of Environmental Protection. "It's counter-intuitive
to think we would have this type of problem out there."
But the problem is there: A follow-up survey in the spring found
even higher rates of "intersex" bass -- as the affected
males are called. A study of 66 male smallmouths from the South
Branch found that about 79 percent showed such symptoms, according
to U.S. Geological Survey data.
The scientists are now analyzing water samples from the South
Branch and the Cacapon River -- a nearby Potomac tributary where
intersex bass were also found. The chemicals they're looking for now
are not the well-known pollutants that the state already tests for,
such as nitrogen and phosphorus from manure and metals from mine
runoff.
Instead, the culprit is probably in a class called "emerging
contaminants," which includes everything from caffeine and
prescription drugs to hormones excreted by livestock or humans.
Some of these pollutants have been linked to developmental
problems in wildlife. Scientists believe that fish, especially,
absorb hormones from other animals, as well as other chemicals that
their bodies mistake for hormones.
One recent study near sewage plants in Colorado found male fish
whose bodies were trying to produce eggs and some females whose
reproductive systems were out of sync. Other studies have found
similar effects from the hormones in cow manure and from chemicals
from a wood-pulp plant.
"It is certainly an alarming situation that we're seeing
more and more gross effects," said David O. Norris, a professor
who worked on the Colorado study.
These emerging contaminants were hard to detect without the
finely tuned equipment developed recently. The first nationwide
survey, conducted in 1999 and 2000, found hormones in about 37
percent of the streams surveyed and caffeine in more than half.
The only testing in the Potomac, done in Washington in 2002,
found low levels of caffeine, plus the insecticide DEET and
chemicals produced when a body breaks down nicotine. There were also
a few suspected endocrine disruptors, including chemicals found in
hand soap and household cleaners.
As of now, little is done to test for these chemicals -- either
in river water or in drinking water. The U.S. Environmental
Protection Agency has not set standards, saying more research is
needed to determine which contaminants are harmful and what levels
are unsafe.
West Virginia, Virginia, Maryland and the District do not test
river water regularly for drugs or hormones. The same goes for
drinking water after it is processed by the Washington Aqueduct,
supplying the District, Arlington County and Falls Church, and the
Washington Suburban Sanitary Commission.
Still, the West Virginia study has spurred scientists to look for
more information. Researchers at the U.S. Fish and Wildlife Service
are seeking money for a much larger study across the Potomac
watershed. They want to look for intersex bass and potentially
disruptive chemicals in sites including the Blue Plains sewage plant
in Southwest Washington.
Another federal study is underway in Rock Creek, looking for
intersex symptoms and other health problems in a species of fish
called white suckers.
Scientists across the region stressed that their work is just
beginning. "We really don't know what's going on," said
Vicki S. Blazer, a researcher for the geological survey in West
Virginia.
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