Moments later, dozens of stunned fish float to the surface.
Federal scientists scoop them up and transfer them into 50-quart
Coleman ice chests for transport to a makeshift lab on the dusty lakeshore.
Within the hour, the researchers will club the seven-pound common carps to
death, draw their blood, snip out their gonads and pack them in aluminum foil
and dry ice.
The specimens will be flown across the country to laboratories where
aquatic toxicologists are studying what happens to fish that live in water
contaminated with at least 13 different medications — from over-the-counter
pain killers to prescription antibiotics and mood stabilizers.
More often than not these days, the laboratory tests bring unwelcome
results.
A five-month Associated Press investigation has determined that
trace amounts of many of the pharmaceuticals we take to stay healthy are
seeping into drinking water supplies, and a growing body of research indicates
that this could harm humans.
But people aren't the only ones who consume that water. There is
more and more evidence that some animals that live in or drink from streams and
lakes are seriously affected.
Pharmaceuticals in the water are being blamed for severe
reproductive problems in many types of fish: The endangered razorback sucker
and male fathead minnow have been found with lower sperm counts and damaged
sperm; some walleyes and male carp have become what are called feminized fish,
producing egg yolk proteins typically made only by females.
Meanwhile, female fish have developed male genital organs. Also,
there are skewed sex ratios in some aquatic populations,
and sexually abnormal bass that produce cells for both sperm and eggs.
There are problems with other wildlife as well: kidney failure in
vultures, impaired reproduction in mussels, inhibited growth in algae.
"We have no reason to think that this is a unique
situation," says Erik Orsak, an environmental
contaminants specialist with the U.S. Fish and Wildlife Service, pulling off
rubber gloves splattered with fish blood at
For example:
_In a broad study still under way, fish collected in waterways near
or in Chicago; West Chester, Pa.; Orlando; Dallas; and Phoenix have tested
positive for an array of pharmaceuticals — analgesics, antibiotics,
antidepressants, antihistamines, anti-hypertension drugs and anti-seizure medications.
_That research follows a 2003 study in northern
_In several recent studies of soil fertilized with livestock manure
or with the sludge product from wastewater treatment plants, American
scientists found earthworms had accumulated those same compounds, while
vegetables — including corn, lettuce and potatoes — had absorbed antibiotics.
"These results raise potential human health concerns," wrote
researchers.
_Blood and liver samples of bull sharks in
_And in
Elsewhere in the world — from the icy streams of
More than 100 different pharmaceuticals have been detected in
surface waters throughout the world.
"It's inescapable," said Sudeep
Chandra, an assistant professor at
While some researchers have captured wildlife and tested it for
pharmaceuticals, many more have brought wildlife into their laboratories and
exposed them to traces of human pharmaceuticals at levels similar to those
found in water, aquatic plants and animals.
The results have been troubling.
Freshwater mussels exposed to tiny amounts of an antidepressant's
active ingredient released premature larvae, giving the next generation lower
odds of survival; in a separate lab study, the antidepressant also stunted reproduction
in tiny fresh water mud snails.
When researchers slid hydras — a tiny polyp that under a microscope
looks like a slender jellyfish — into water tainted with minute amounts of
pharmaceuticals, their mouths, feet and tentacles stopped growing. While the
hydras are minuscule, the implications are grave: Chronic exposure to trace
levels of commonly found pharmaceuticals can damage a species at the foundation
of a food pyramid.
Tiny zooplankton, another sentinel species, died off in the lab when
they were exposed to extremely small amounts of a common drug used to treat
humans suffering from internal worms and other digesting parasites.
In a landmark, seven-year study published last year, researchers
turned an entire pristine Canadian lake into their laboratory, deliberately
dripping the active ingredient in birth control pills into the water in amounts
similar to those found to have contaminated aquatic life, plants and water in
nature.
After just seven weeks, male fathead minnows began producing yolk
proteins, their gonads shrank, and their behavior was feminized — they fought
less, floating passively. They also stopped reproducing, resulting in
"ultimately, a near extinction of this species from the lake," said
the scientists.
While the Canadian study was prompted by human intervention, similar
die-offs have occurred in the wild.
In
"The death of those vultures — the fact that you could get a
complete collapse of a population due to pharmaceuticals in the environment —
that was a powerful thing," said Christian Daughton,
an EPA researcher in
In November, at the annual Society of Environmental Toxicology and
Chemistry meeting in Milwaukee, 30 new studies related to pharmaceuticals in
the environment were presented — hormones found in the Chicago River;
abnormalities in Japanese zebra fish; ibuprofen, gemfibrozil,
triclosan and naproxen in the lower Great Lakes.
Many of those studies refer to the heralded research at
"Typically we see low levels of sex steroids, limited
testicular function, low sperm count, that kind of thing," he said
slipping the fish into a holding tank and closing the lid. "We'll have to
wait and see about this fellow."
These carp live, eat, reproduce and die at the mouth of what amounts
to a 30-mile-long drainage system that starts within the toilets and sinks of
the casinos, hotels and homes of
Some 180 million gallons of effluent are discharged into the channel
each day from three wastewater treatment plants. The daily sewage discharge is
expected to increase to 400 million gallons a day by 2050.
The USGS and U.S Fish and Wildlife Service tracked the channel from
its origins, before the inflow from the sewage plants, to where it empties into
Not far from the mouth of the drainage channel — amid the fishing
boats and sightseeing tours — water is sucked into a long pipe, destined for a
drinking water treatment plant, then Las Vegas — thus beginning the cycle all
over again.
Other communities in
"Lake Mead is a fortuitous worst-case scenario" for study,
said environmental toxicologist Greg Moller, holding
a bottle of Lake Mead water he planned to take back to his lab at the
University of Idaho. "You've got the wastewater, you've got the documented
impact on wildlife, and you have drinking water uptake."
Although more than eight million tourists, including 500,000
anglers, visit the reservoir annually, there are no warnings about the
contaminants. No signs. No advisories.
That's not unusual. Scientists have been finding pharmaceuticals in
hundreds of other public waterways across the nation and throughout the world —
almost always without public fanfare, as documented in the AP investigation.
At the same time, scientists are looking for remedies. In
"We put a little bit of estrogen in here, and then we added a particular bacteria, and guess what? The bacteria are
consuming the estrogen," he said. Someday, perhaps, scientists will be
able to use these special bacteria to clean estrogen out of contaminated water.
"It's early, but it's promising," he said.
National Writer Martha Mendoza reported from