[Pharmwaste] A Pharmacy Runs Through It

[Tenace, Laurie]

http://www.courant.com/news/local/hc-finalriverspharm.artoct27,0,6953033.=
stor
y?coll=3Dhc-headlines-local

ALBUQUERQUE, N.M. -- Last fall, Maceo Carrillo Martinet, a graduate =
student
in biology at the University of New Mexico, took a sample from a well =
beside
the Rio Grande here and shipped it to a laboratory for analysis.

Among other compounds, the sample, taken within a large cottonwood =
forest,
contained 1,100 parts per trillion of DEET, the chemical used in insect
repellants.
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This was startling. It was nearly double the level found upriver, above =
the
Albuquerque wastewater treatment plant, and strongly suggested that some =
of
the DEET came from treatment plant discharges.

"We put it on our skin, we go home, we wash or we take a shower and it =
goes
into the system," Martinet said. "It actually does not biodegrade in
treatment plants."

Pharmaceuticals and personal care products, such as prescription and
nonprescription drugs and substances like insect repellents and
disinfectants, are turning up in many U.S. rivers.

"As we look more and more, these compounds are showing up in a lot of
places," said Dana W. Kolpin, a research hydrologist with the U.S. =
Geological
Survey who published the first major overview of the pharmaceutical =
question
only three years ago. It found, for example, that DEET, steroids and a =
kind
of fire retardant were present in the waters of a majority of 139 =
streams
tested in 30 states.

Water samples from rivers receiving treated wastewater often reveal the
presence of insecticides, antidepressants such as Prozac, disinfectants,
antibiotics and caffeine, too.

"You can find caffeine in just about any river with a wastewater =
treatment
plant discharging into it," said Judith L. Meyer, a University of =
Georgia
professor whose research focuses on stream ecology.

Wastewater treatment plants can break down some of these substances =
during
treatment, but many pass right through or are only partly intercepted. =
Cities
and towns aren't doing anything wrong, because the plants were never =
designed
to treat substances such as steroids and antidepressants. Moreover, =
there are
no regulatory standards for these substances in wastewater.

While some of the substances have been around for many years, only in =
recent
years has the analytical equipment been available to measure them in a
comparatively inexpensive and speedy manner. And so it is only in the =
past
few years that researchers "fully realized that it is as widespread as =
it
appears to be," said Paul E. Stackelberg, a hydrologist with the USGS.

Already, however, there are indications that some of these substances,
typically found in tiny amounts, are harming some forms of aquatic life,
notably fish and amphibians. Whether they pose any threat to humans is
essentially unknown.

Water Analyzed

In one new study conducted by the U.S. Geological Survey and the Centers =
for
Disease Control and Prevention, samples of water were analyzed from =
streams
that both receive treated wastewater effluent and are used for drinking
water, after treatment.

They found that prescription drugs and other organic wastewater =
contaminants
survived treatment processes and were present in drinking water, though =
in
concentrations far below what would constitute a therapeutic dose.

For example, carbamazepine, an anti-epileptic drug, has been identified =
in
many rivers, and was identified in the unnamed stream used in the study. =
But
if a person drank 2 liters of water a day for 70 years at the =
concentrations
found in that stream, he or she would ingest only 13 milligrams of the =
drug,
far below a single therapeutic dose of the drug, which is 100 milligrams =
or
more.

"Nevertheless, most studies on the therapeutic effects of drugs are =
based on
the short-term ingestion of relatively high doses; little is known about
potential health effects associated with long-term chronic ingestion of =
low
concentrations through drinking water," according to that study.

"It's a natural question to ask," said Stackelberg, one of the authors =
of
that study. "But here, really, at this point there is no response. There =
have
been no studies conducted to make that determination."

Some of these compounds break down more quickly in the environment than
others. It appears that DEET does not readily biodegrade when it leaves
wastewater treatment plants, Martinet said, which raises the question of
whether it might accumulate in groundwater or sediments and increase =
over
time to more troublesome levels. The U.S. Environmental Protection =
Agency
classifies DEET as slightly toxic, but whether the levels in rivers like =
the
Rio Grande are anything to worry about is unknown.

A recent study looking more closely at DEET, in which Kolpin was one of =
the
authors, suggested additional studies on DEET's potential toxicity to =
aquatic
life because it is so widespread in streams receiving treated =
wastewater.

Bryan Brooks, an assistant professor of environmental studies at Baylor
University in Texas, tested sunfish, channel catfish and black crappie =
from
Pecan Creek. The stream, near Dallas, receives almost all of its flow =
from a
wastewater treatment plant and connects to a drinking water supply.
He found tiny amounts of fluoxetine, the active ingredient in Prozac, in
liver and brain tissue.

Prozac has been identified in many streams at low levels. "It is going =
to be
fairly common to detect in rivers receiving wastewater treatment =
effluent,
especially when the wastewater treatment plants are a significant source =
of
flow," said Marsha Black, an ecotoxicologist at the University of =
Georgia.

In her own lab experiments, Black found that even low levels of the
antidepressant harmed amphibians and fish.

Tadpoles exposed to levels of Prozac like those found in streams were =
smaller
when they turned into frogs than tadpoles that were not exposed to the =
drug,
she found. At higher concentrations than typically seen in the =
environment,
fish became lethargic. In both instances, that could leave the animals =
far
more vulnerable to predation or environmental stress, she said.

Using outdoor, artificial streams fed by treated municipal wastewater, =
Brooks
found that male fish developed some female sexual characteristics. Such =
fish
also have been encountered in the wild, recently on the South Branch of =
the
Potomac River in West Virginia.

Still, Brooks cautions that concentrations of personal care products and
pharmaceuticals are small, and that extensive research will be needed to
determine if there is any effect on humans.

"It is not prudent to make some sort of quick decision," he said. "We =
need to
make sure if we make decisions that they are science-based."

Brooks, in fact, is skeptical of any human impact. "To make the leap to =
human
health, I just don't see it," he said. "Even if a compound were stable =
enough
to be taken up by fish and eaten by humans, they're at such low levels =
you
would have to eat hundreds of meals to even approach one therapeutic =
dose."

On the other hand, the impact on frogs, fish, amphibians, even algae "is =
a
different story altogether," he said.

Researchers say there are other questions to be answered. Even if
pharmaceuticals meant to be ingested are found only at low levels, what =
about
compounds not meant to be ingested at all, such as flame retardants,
pesticides, DEET and other substances? And what if there is a =
synergistic
effect among any of these many compounds in the water?

And even if a compound breaks down relatively quickly in the =
environment,
unlike such well-known enduring pollutants as PCBs or DDT, what is the
long-term impact if the substance is gushing from treatment plant =
effluent
pipes every day? Brooks calls this "pseudo-persistence."

However widespread they may be, these contaminants are only just =
entering the
public consciousness.

On a recent day, as he walked along the banks of the Rio Grande just =
south of
Albuquerque, Martinet ticked off a list of the compounds found in the =
river
and groundwater, including fire retardants and the ubiquitous caffeine.

"We've been using DEET for a while, birth control pills for a while, =
caffeine
forever," he said.

"What happens to these compounds once they are in the system is a huge, =
huge
question mark right now."=20

I love the title!

Laurie J. Tenace
Environmental Specialist
Florida Department of Environmental Protection
2600 Blair Stone Road, MS 4555
Tallahassee, Florida 32399-2400
PH: (850) 245-8759
FAX: (850) 245-8811
Laurie.Tenace@dep.state.fl.us
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view our mercury web pages at:=20
http://www.dep.state.fl.us/waste/categories/mercury/default.htm
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