-
- A new class of water pollutants has been
discovered during the past six years.[1] Pharmaceutical drugs given to
people and to domestic animals --including antibiotics, hormones, strong
pain killers, tranquilizers, and chemotherapy chemicals given to cancer
patients --are being measured in surface water, in groundwater, and in
drinking water at the tap. Large quantities of drugs are excreted by humans
and domestic animals, and are distributed into the environment by flushing
toilets and by spreading manure and sewage sludge onto and into soil. German
scientists report that anywhere from 30 to 60 drugs can be measured in
a typical water sample, if anyone takes the time to do the proper analyses.[2]
The concentrations of some drugs in water are comparable to the low parts-per-billion
(ppb) levels at which pesticides are typically found.[1] To some people
this is reassuring, but others are asking, "What is the long-term
effect of drinking, day after day, a dilute cocktail of pesticides, antibiotics,
pain killers, tranquilizers and chemotherapy agents?" Of course no
one knows the answer to such a question --it is simply beyond the capabilities
of science to sort out the many chemical interactions that could occur
in such a complex chemical soup. The only solution to such a problem would
be prevention.
-
- The first study that detected drugs in
sewage took place at the Big Blue River sewage treatment plant in Kansas
City in 1976. The problem was duly recorded in scientific literature and
then ignored for 15 years.[3] In 1992, researchers in Germany were looking
for herbicides in water when they kept noticing a chemical they couldn't
identify.[4] It turned out to be clofibric acid (CA), a drug used by many
people in large quantities (1 to 2 grams per day) to reduce cholesterol
levels in the blood.[1] Clofibric acid is 2-(4)-chlorophenoxy-2-methyl
propionic acid, a close chemical cousin of the popular weed killer 2,4-D.[1]
Based on that early discovery, the search for clofibric acid (CA) in the
environment was stepped up.
-
- Since 1992, researchers in Germany, Denmark
and Sweden have been measuring CA and other drugs in rivers, lakes, and
the North Sea. To everyone's surprise, it turns out that the entire North
Sea contains measurable quantities of clofibric acid. Based on the volume
of the Sea, which is 12.7 quadrillion gallons (1.27 x 10E16 gallons), and
the average concentration of CA, which is 1 to 2 parts per trillion (ppt),
researchers estimate that the Sea contains 48 to 96 tons of clofibric acid
with 50 to 100 tons entering the Sea anew each year.[1] The Danube River
in Germany and the Po River in Italy also contain measurable quantities
of clofibric acid.[5,6] Of more immediate concern to humans is the finding
that tap water in all parts of the city of Berlin contains clofibric acid
at concentrations between 10 and 165 ppt.[5] The water supplies of other
major cities remain to be tested.
-
- As a result of this European work, a
few U.S. researchers are now beginning to pay attention to drugs in the
environment. Individual scientists within the U.S. Food and Drug Administration
(FDA) have been concerned about this problem for a decade,[7] but so far
FDA has taken the official position that excreted drugs are not a problem
because the concentrations found in the environment are usually below one
part per billion (ppb).[2]
-
- Drugs are designed to have particular
characteristics. For example, 30% of the drugs manufactured between 1992
and 1995 are lipophilic, meaning that they tend to dissolve in fat but
not in water.[8] This gives them the ability to pass through cell membranes
and act inside cells. Unfortunately, it also means that, once they are
excreted into the environment, they enter food chains and concentrate as
they move upward into larger predators. Many drugs are also designed to
be persistent, so that they can retain their chemical structure long enough
to do their therapeutic work. Unfortunately, after they are excreted, such
drugs also tend to persist in the environment. A landfill used by the Jackson
Naval Air Station in Florida contaminated groundwater with a plume of chemicals
that has been moving slowly underground for more than 20 years. The drugs
pentobarbital (a barbiturate), meprobamate (a tranquilizer sold as Equanil
and Miltown) and phensuximide (an anticonvulsant) are still measurable
in that groundwater plume.[8,pg.362]
-
- When a human or an animal is given a
drug, anywhere from 50% to 90% of it is excreted unchanged. The remainder
is excreted in the form of metabolites --chemicals produced as byproducts
of the body's interaction with the drug. Researchers report that some of
the metabolites are more lipophilic and more persistent than the original
drugs from which they were derived. Because of the complexity of the chemistry
involved in drug metabolism, and the interactions of the metabolites with
the natural environment, Danish researchers say is it "practically
impossible to estimate predicted environmental concentrations (PEC) of
any medical substances with available knowledge."[8,pg.385]
-
- Yet U.S. regulatory policy for new drugs
depends entirely upon estimating concentrations that might result from
excretion. When a new drug is proposed for market, FDA requires the manufacturer
to conduct a risk assessment that estimates the concentrations that will
be found in the environment. If the risk assessment concludes that the
concentration will be less than one part per billion, the drug is assumed
to pose acceptable risks.[2] FDA has never turned down a proposed new drug
based on estimated environmental concentrations, and no actual testing
is conducted after a drug is marketed to see if the environmental concentration
was estimated correctly.
-
- German chemists have found that many
drugs can be measured at environmental concentrations that exceed one ppb.
And of course several drugs measured together can exceed one ppb. Furthermore,
there is ample evidence from research conducted during the past decade
showing that some chemicals have potent effects on wildlife at concentrations
far below one ppb. For example estradiol, the female sex hormone (and a
common water pollutant), can alter the sex characteristics of certain fish
at concentrations of 20 ppt, which is 1/50 of one ppb.[2] Another problem
resulting from drugs in the environment is bacteria developing resistance
to antibiotics. The general problem of antibiotic-resistant bacteria has
been recognized for more than a decade. (See REHW #402.) Antibiotics are
only useful to humans so long as bacteria do not become resistant to their
effects. Hospital sewage systems discharge substantial quantities of antibiotics
into the environment.[9] Bacteria exposed to antibiotics in sewage sludge,
or water, have an opportunity to develop resistance. Janet Raloff of SCIENCE
NEWS quotes Stuart Levy, who directs the Center for Adaptation Genetics
and Drug Resistance at Tufts University in Boston, saying, "[T]hese
antibiotics may be present at levels of consequence to bacteria --levels
that could not only alter the ecology of the environment but also give
rise to antibiotic resistance."[2]
-
- What can we learn from the emergence
of this new problem? 1) Hospitals and the health care industry are the
major sources of these problems, especially antibiotics and chemotherapy
chemicals.[10] The large national coalition of environmental and health
groups, Health Care Without Harm,[11] might consider tackling this difficult
but important problem.
-
- 2) Sewage sludge provides a major pathway
by which drugs enter the environment. Until the drug problem is understood
and controlled, it provides a solid scientific rationale for labeling sewage
sludge a dangerous soil amendment, the use of which should be forbidden.
-
- 3) For a long time, people have worried
that the world was going to run out of natural resources. It is now apparent
that we have run out places to throw things away. There is no place left
where we can throw away exotic substances without affecting people or wildlife
(upon whose well being we ultimately depend).
-
- From the viewpoint of disposal, not many
decades ago the world still looked pretty empty. Today there can be no
doubt that the world is full --full of people armed with double-edged technologies.
To survive in a full world will require quite different attitudes. We need
to curb our numbers. We need to curb our technologies. We need to curb
our appetites. And we need to operate from a position of humility. We should
assume that anything we do will have negative consequences on the rest
of the planet. We must limit our technological interventions into nature
long before we have definitive scientific proof of harm. This is the principle
of precautionary action, and if we don't adopt it, nature will get along
just fine without us.
-
- --Peter Montague (National Writers Union,
UAW Local 1981/AFL-CIO)
-
- ___________________
-
- [1] Hans-Rudolf Buser and Markus D.
Muller, "Occurrence of the
- Pharmaceutical Drug Clofibric Acid and
the Herbicide Mecoprop in
- Various Swiss Lakes and in the North
Sea," ENVIRONMENTAL SCIENCE
- AND TECHNOLOGY Vol. 32, No. 1 (1998),
pgs. 188-192.
- [2] Janet Raloff, "Drugged Waters,"
SCIENCE NEWS Vol. 153, No. 12
- (March 21, 1998), pgs. 187-189.
- [3] C. Hignite and D.L. Azarnoff, "Drugs
and drug metabolites as
- environmental contaminants: chlorophenoxyisobutyrate
and
- salicyclic acid in sewage water effluent,"
LIFE SCIENCES Vol. 20,
- No. 2 (January 15, 1977), pgs. 337-341.
- [4] H.J. Stan and Thomas Heberer, "Pharmaceuticals
in the Aquatic
- Environment," ANALUSIS MAGAZINE
Vol. 25, No. 7 (1997), pgs.
- M20-M23.
- [5] Thomas Heberer and H.-J. Stan, "Determination
of Clofibric
- Acid and N-(phenylsulfonyl)-Sarcosine
in Sewage, River, and
- Drinking Water," INTERNATIONAL
JOURNAL OF ENVIRONMENTAL
- ANALYTICAL CHEMISTRY Vol. 67 (1997),
pgs. 113-124. And see:
- Thomas Heberer and others, "Detection
of Drugs and Drug
- Metabolites in Ground Water Samples
of a Drinking Water Treatment
- Plant," FRESENIUS ENVIRONMENTAL
BULLETIN Vol. 6 (1997), pgs.
- 438-443.
- [6] "Pille im Brunnen [Pills in
the Fountain]," DER SPIEGEL No.
- 26 (June 24, 1996), pgs. 154-155, translated
for us by Thea
- Lindauer, Annapolis, Maryland.
- [7] Personal communication from Maurice
Zeeman, U.S.
- Environmental Protection Agency, March,
1998.
- [8] B. Halling-Sorensen and others,
"Occurrence, Fate and Effects
- of Pharmaceutical Substances in the
Environment --A Review,"
- CHEMOSPHERE Vol. 36, No. 2 (1998), pgs.
357-393.
- [9] Andreas Hartmann and others, "Identification
of Fluoroquinone
- Antibiotics as the Main Source of umuC
Genotoxicity in Native
- Hospital Wastewater," ENVIRONMENTAL
TOXICOLOGY AND CHEMISTRY Vol.
- 17, No. 3 (1998), pgs. 377-382.
- [10] T. Steger-Hartmann and others,
"Biological Degradation of
- Cyclophosphamide and Its Occurrence
in Sewage Water,"
- ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
Vol. 36 (1997), pgs.
- 174-179.
- [11] Contact: Charlotte Brody, Health
Care Without Harm, c/o CCHW
- Center for Health, Environment and Justice,
P.O. Box 6806, Falls
- Church, Virginia 22040. Phone (703)
237-2249. See
- <http://www.noharm.org/www.noharm.org.
- Descriptor terms: drugs; pharmaceuticals;
water pollution;
- sewage sludge; precautionary principle;
fda; north sea; germany
-
- __________________________
-
- NOTICE
- Environmental Research Foundation provides
this electronic
- version of RACHEL'S ENVIRONMENT &
HEALTH WEEKLY free of charge
- even though it costs our organization
considerable time and money
- to produce it. We would like to continue
to provide this service
- free. You could help by making a tax-deductible
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- (anything you can afford, whether $5.00
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- your tax-deductible contribution to:
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- --Peter Montague, Editor
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