[Pharmwaste] Man-Made Chemicals May Put Strain on Fish
dldebiasi at deq.virginia.gov
Tue Mar 18 14:11:39 EDT 2008
Man-Made Chemicals May Put Strain on Fish
By David A. Fahrenthold
Washington Post Staff Writer
Tuesday, March 18, 2008; B01
The Potomac River contains an array of man-made chemicals that could
play havoc with animals' hormone systems, federal scientists have found
in their best glimpse yet of the river's problems with a mysterious new
class of pollutant.
The research, unveiled at a conference last week, found more than 10 of
the compounds, including pesticides, herbicides and artificial
fragrances. Through an accident of chemistry, formulas designed to kill
bugs or add smell to soap might also interfere with vital signals in
fish, amphibians and other creatures.
The scientists said they hoped this new research might explain one of
the Potomac's most bizarre discoveries: Some male fish have begun
growing eggs. Scientists said there was no evidence of a threat to human
Taken with a recent report that drinking water samples from the river
contain traces of drugs, the results provide troubling evidence about
the river's health. People living along the Potomac, the results showed,
have widely tainted it with pollutants that scientists are just
beginning to understand.
"The types of things we're finding are the types of things that are
associated with everyday life," said David Alvarez, a U.S. Geological
Survey research chemist who analyzed samples from the Potomac. The
contaminants flow into the river from sewer plants and in rainwater
washing off of farm fields and suburban lawns, he said.
"If it's something we're using, ultimately it's going to end up in the
water," Alvarez said.
The chemicals in the study presented at the conference, held in Berkeley
Springs, W.Va., are suspected by scientists to be "endocrine
disruptors." This group of contaminants interferes with natural hormone
systems, twisting or aborting the processes that hormones control. The
conference was sponsored by the Metropolitan Washington Council of
Much about the compounds is still unclear, including which of them
really do have bad effects.
In 1996, the Environmental Protection Agency was ordered by Congress to
create a testing program to identify endocrine disruptors, but the tests
have not begun.
Along the Potomac, researchers have long suspected that
hormone-mimicking chemicals were the cause of the "intersex" fish. The
first of these creatures, male fish with eggs growing in their sex
organs, were noticed in a rural West Virginia tributary in 2003.
Follow-up studies have found the fish throughout the
watershed, including near the Woodrow Wilson Bridge.
To investigate, scientists from the Geological Survey, the U.S. Fish and
Wildlife Service and the Maryland Department of Natural Resources began
taking samples of water in 2005 and 2006.
In the river near the District's Blue Plains sewage plant, scientists
suspended a device intended to serve as a facsimile fish. The device had
a plastic-coated tube, which simulated a fish's permeable skin, and a
layer of simulated fat.
"We're trying to see what the fish sees," Alvarez said.
They saw a lot. The tests on this fake fat revealed a range of
potentially worrisome pollutants. Most have been found in other streams
around the United States, scientists said, adding that the pollutants
are of special concern in the Washington area because of the intersex
The discoveries included trace amounts of atrazine, a herbicide commonly
used on farm fields. The EPA has put the herbicide on a list of
chemicals to be tested for hormone-mimicking effects. Some scientific
studies have already linked atrazine to sexual abnormalities in frogs
"There's a weight of evidence that something's going on here," said
Nancy Golden, a wildlife toxicologist with the Fish and Wildlife
Service, who said she was summarizing a common view, not her own
A company that makes atrazine, the agribusiness Syngenta in Basel,
Switzerland, has insisted that the chemical presents no undue risks if
Also found in the Potomac were the insecticides chlorpyrifos and
endosulfan and the herbicide metolachlor. All three are on the EPA's
list of chemicals to be tested for hormone-mimicking effects.
Researchers said the chemicals, as well as atrazine, might have washed
off suburban lawns in the Washington area or farm fields farther
Other chemicals were apparently added, unknowingly, by urban residents
in the course of daily life. These included two chemicals used to add
fragrance to perfumes, soaps and other products: tonalide, and
galaxolide. The chemicals, when washed down drains, can pass through
sewage treatment systems and into rivers.
Geological Survey researcher Vicki S. Blazer said that some evidence
suggested all of the chemicals could interfere with hormones.
The research study did not look for traces of pharmaceuticals, but a
separate round of federal testing has found traces of six
pharmaceuticals in local drinking water taken from the Potomac.
Researchers said this new set of results marked a big step toward
finding the reason for the Potomac's gender-confused fish, though it did
not solve the case.
"We're beginning to narrow down some of the . . . possible chemical
causes," Blazer said. "Now we have a better idea of what's there."
The repercussions for human health are also unclear. At the Washington
Aqueduct, the agency that turns river water into tap water for the
District, Arlington County, Falls Church and parts of Fairfax County,
the treatment process is not designed to remove the chemicals.
The agency's general manager, Thomas P. Jacobus, said tests on
"finished" water showed trace levels of both atrazine and metolachlor
last year. He said, however, that the levels of the chemicals were so
low they did not seem to pose a danger.
Ed Merrifield, executive director of the environmental group Potomac
Riverkeepers, said he still wants more information about the impact of
"None of these chemicals should be in our water," he said.
Deborah L. DeBiasi
Email: dldebiasi at deq.virginia.gov
WEB site address: www.deq.virginia.gov
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
PPCPs, EDCs, and Microconstituents
Mail: P.O. Box 1105, Richmond, VA 23218 (NEW!)
Location: 629 E. Main Street, Richmond, VA 23219
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