Seattle
Post-Intelligencer
4 June 2003
Birth
control may be harming state's salmon
Synthetic estrogen in water seems to affect reproduction
By
Lisa Stiffler
Birth-control
pills can curb the reproduction of more than just the women taking
them. Western Washington scientists have found that synthetic estrogen
-- a common ingredient in oral contraceptives -- can drastically
reduce the fertility of male rainbow trout.
The
man-made compounds are showing up in waterways around the nation
-- pumped into rivers, lakes and Puget Sound with water from sewage-treatment
plants.
And
they're being found at levels that can harm fish, possibly even
this region's struggling salmon populations.
"It
is disturbing in the extreme," said Kaitlin Lovell, salmon-policy
coordinator for Trout Unlimited in Portland.
The
research by scientists at the Battelle Marine Sciences Laboratory
in Sequim is unique for its focus on trout, which is related to
salmon, and for looking at reproductive effects on adult fish rather
than juveniles.
How
fish are affected by such chemicals in the wild remains unclear.
"It's something we're concerned about," said Irvin Schultz,
a senior research scientist at the lab.
In
the experiment, adult trout in caged pens were exposed to ethynylestradiol,
a synthetic estrogen. After two months of exposure, the fish were
spawned with a healthy female. Researchers discovered that the exposed
trout were half as fertile as fish kept in clean water.
The
research by the government-funded lab is outlined in this month's
issue of the journal Environmental Toxicology and Chemistry.
The
findings are likely to fuel concerns about the environmental effects
of chemicals that aren't being filtered out by sewage plants, including
pharmaceuticals and pesticides that can mimic hormones.
In
frogs, river otters and fish, scientists are "finding the presence
of female hormones making the male species less male," said
Doug Myers, wetlands and habitat specialist for the Puget Sound
Action Team, the government agency coordinating restoration of the
Sound.
There
are no standards for how much synthetic estrogen and other hormones
can be released in sewage and wastewater, and treatment plants generally
do not monitor for it.
The
Environmental Protection Agency is studying which of these compounds
have harmful effects. Then the next step will be testing for their
presence in waste water. New regulations could follow.
Although
trout don't have the ability to rid themselves of the synthetic
hormones, Schultz doesn't think it poses a serious threat to people
eating the fish because the levels in the environment are low.
There
are some concerns about wastewater that is being recycled back into
the environment, particularly in desert areas, where it might mix
with groundwater that could be used for drinking. An official with
King County said there is little cause for concern about human risks
locally.
New
sewage-treatment facilities are looking into special membranes that
will help pull some of these contaminants out, said John Smyth,
an official with King County's technology-assessment program. It's
currently being considered for the planned Brightwater treatment
plant that will serve King and Snohomish counties.
"Agencies
like us all over the country are trying to figure out ways to tackle
this thing," Smyth said.
The
researchers in Sequim tested the effects of synthetic estrogen at
three different levels. The scientists were surprised that even
the lowest level -- 80 times lower than levels measured in the wild
-- had an effect on fertility.
The
scientists would like to do more tests to identify the smallest
concentrations that can harm fish.
They
were unable to figure out how the estrogen was causing the reduction
in fertility. It appears not to affect the swimming ability of sperm.
With
so many unanswered questions about what compounds are getting into
the environment, their effects and how to get them out of the wastewater,
environmentalists and scientists are concerned.
Said
Trout Unlimited's Lovell, "If anything, these problems are
only going to get worse before they get better."
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