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Hi Zee

5 years ago and folks will not acknowledge the import.

Bill
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http://www.findarticles.com/p/articles/mi_m1200/is_14_157/ai_61617771

More Waters Test Positive for Drugs - pharmaceutical contamination
Science News,  April 1, 2000  by J. Raloff

 
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Over the past decade, European chemists have been documenting
widespread pharmaceutical contamination of their lakes, streams, and
groundwater. In San Francisco this week, U.S. and Canadian scientists
offered preliminary confirmation that traces of drugs, excreted ?, by
people and livestock, similarly pollute American waters.

They presented their findings at the first major American symposium on
pharmaceuticals in water, held as part of the American Chemical
Society's spring national meeting.

Water pollution by drugs "is a newly emerging issue," observes
Christian G. Daughton, a symposium co-organizer and chief of
environmental chemistry at the Environmental Protection Agency's
National Exposure Research Laboratory in Las Vegas. By offering a U.S.
venue for the meeting--and participation by many European leaders in
this field (SN: 3/21/98, p.187)--he hoped to awaken domestic interest
and catalyze research on the topic, he says.

Ironically, Daughton notes, EPA scientists examining the sludge from a
U.S. sewage-treatment plant 20 years ago found that the incoming sewage
contained excreted aspirin, caffeine, and nicotine. Daughton says that
the findings were written off as a curiosity and all but forgotten.

At about the same time, recalls Herman Bouwer of the U.S. Agricultural
Research Service in Phoenix, the cholesterol-lowering drug clofibric
acid turned up in a groundwater reservoir being tapped to meet the
Phoenix community's thirst. The drug had entered with treated sewage,
which the city had been using to replenish the aquifer.

"At the time," Bouwer recalls, "we didn't pay attention to the
finding." It should have been a wake-up call, he now argues, because if
clofibric acid could pass through a sewage-treatment plant and percolate
through soil unscathed, so could a host of other drugs.

And they do, new studies show.

Chris Metcalfe of Trent University in Peterborough, Ontario, reports
finding a broad mix of drugs, including anticancer agents, psychiatric
drugs, and anti-inflammatory compounds. "Levels of prescription drugs
that we have leaving sewage-treatment plants in Canada are sometimes
higher than what's being seen in Germany," he says.

He explains that many North American cities employ more rudimentary
sewage treatment than those in Germany. Daughton observes also that some
1 million U.S. homes send their essentially untreated sewage directly
into the environment.

Two years ago, the symposium's other co-organizer, Thomas A. Ternes,
documented unexpectedly high concentrations of drugs--many measured in
parts per billion (ppb)--both in raw sewage and in water leaving
treatment plants in Germany. The chemist, who is at the Institute for
Water Research and Water Technology in Wiesbaden, Germany, now finds
that these drugs enter groundwater.

Sewage effluent can amount to at least half the water in many of
Germany's smaller rivers, he notes. Groundwater fed by streams carrying
relatively undiluted effluent can be tainted with 1 ppb carbamazepine,
an anticonvulsive drug. Ternes has also detected similar amounts of the
anti-inflammatory drug diclofenac and up to 2.4 ppb of iodine-based
drugs used to improve contrast in X rays.

Because people discard their excess drugs, the town dump can also be a
source of pharmaceutical pollution. Under one landfill, Ternes found
groundwater tainted with 12 ppb clofibric acid and 1 ppb phenazone, an
analgesic.

The latter medication also turned up in groundwater--but at far higher
concentrations--under a leaking dump in Zagreb, Croatia, notes Marijan
Ahel of the Rudjer Boskovic Institute in Zagreb. Some of his water
samples had the drug at as much as 50 times the concentration detected
by Ternes.

In the United States, federal scientists recently began probing another
source of drug pollution--large feedlots for livestock. An estimated 40
percent of the antibiotics produced in the United States is fed to
livestock as growth enhancers. Geochemist Mike Meyer of the U.S.
Geological Survey in Raleigh, N.C., and his colleagues have begun
looking for antibiotics in hog-waste lagoons.

Three drugs frequently show up, one in concentrations approaching 1
part per million. The same three antibiotics, which are also prescribed
for people, often appear in local waters--though usually only at
one-tenth to one-hundredth the concentrations in the lagoons, Meyer
notes. "So, it appears we're getting transport of these antibiotics into
surface and groundwaters," he told SCIENCE NEWS.

His colleagues at the Centers for Disease Control and Prevention in
Atlanta have begun sampling bacteria from the tainted waters to
investigate their responses, to the antibiotics present, Meyer says.
Their findings could begin to resolve a long-standing question: What is
the contribution, if any, of livestock to potentially dangerous
reservoirs of bacteria (SN: 6/5/99, p. 356) resistant to common
antibiotics?

Traces of drugs are sometimes making it all the way into tap water.
Thomas Heberer of the Technical University of Berlin reported finding
traces of at least three pharmaceuticals in samples from his home tap.
The concentrations, however, were near the limits of detection, a few
parts per trillion. Moreover, he found that running this water through
an activated-carbon filter removes all vestiges of the drugs.

Ternes' studies confirm that two disinfection agents--activated carbon
and ozone--which are used in many European drinking-water plants,
generally remove any traces of drugs. It's because these relatively
costly technologies aren't employed for treating sewage, he notes, that
a large share of the drugs flushed down toilets can reach open waters.

To date, the symposium's scientists noted, few if any toxicological
studies have evaluated risks posed by chronic exposure to trace
concentrations of drugs. Most of the participants suspect, however, that
the biggest risks face aquatic life--which may be bathed from cradle to
grave in a solution of drugs of increasing concentration and potency.

David Epel of Stanford University's Hopkins Marine Station in Pacific
Grove, Calif., expressed special concern about new drugs called
efflux-pump inhibitors. Designed to keep microbes from ejecting the
antibiotics intended to slay them (SN: 2/12/00, p. 110), efflux-pump
inhibitors also impede the cellular pumps that nearly all animals use to
get rid of toxicants, he says. If pump-inhibiting drugs enter the
aquatic environment, Epel worries that they might render wildlife
vulnerable to concentrations of pollution that had previously been
innocuous.

COPYRIGHT 2000 Science Service, Inc.