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by
Elizabeth Royte
 Norman
Leonard moved to
Heritage Village, a
sprawling retirement community in western Connecticut, 11 years ago. Its
green-gabled condominiums
and Capes were well
maintained, and the landscapers hadn't
skimped on the
rhododendrons.
A retired CPA, Leonard
considers himself, at age 80, to be in pretty decent shape: He plays
platform tennis on the grounds and hikes
often in nearby forests
and reserves. But still, he takes five different drugs a day to manage his
blood pressure, acid reflux, and high cholesterol. Heritage Village is
home to about 4,000 residents with similar medical profiles, who take an
average of six drugs a day.
And that's a healthy population. In a convalescent home a few miles away,
Patricia Reilly, age 88, wheels herself each morning toward a low shelf.
With a glass of water and small cups of applesauce at the ready, she
prepares to take her morning medicines: nine different types that treat
heart disease, acid reflux, renal stones, a chronic urinary-tract
infection, chronic constipation, migraine headaches, depression, allergic
rhinitis, degenerative arthritis, and intermittent vertigo. The 120
residents of River Glen Health Care Center, where the average age is 90,
take an average of eight drugs a day; the most common among them target
high cholesterol, high blood pressure, depression, and diabetes. Once
swallowed, Reilly's medications will bring her some relief, but their
biological activity won't stop once they leave her body.
When residents of Heritage Village and two other nearby retirement
communities flush their toilets, wastewater laced with traces of
prescription drugs rushes through a series of pipes into the Heritage
Village treatment plant. This flushing is the main pathway by which
pharmaceuticals enter the environment. Hospitals and nursing homes
routinely dump unused or expired pills down the toilet, and consumers have
been advised to do the same; effluent from pharmaceutical manufacturers
also ends up at municipal wastewater treatment plants. Through a process
of settling and aeration, the Heritage Village plant separates liquids
from solids, treats the liquid portion with disinfectant, and then
discharges this effluent into a mini-creek that meanders between the third
green and the seventh tee of the Heritage Village golf course. Making its
way through a riparian band of oaks and maples, the creek fans out into
the Pomperaug River, which loops without further interruption through the
town of Southbury.
The Pomperaug looks no different upstream or down, but studies by the U.S.
Geological Survey (USGS) on other rivers suggest that the Pomperaug below
the effluent creek carries the signatures of drugs consumed by anyone
plumbed into the Heritage Village system. The effect of those drugs on the
environment, and possibly on those who drink water pumped from those
streams, is only beginning to be understood.
We are a nation obsessed with pharmaceuticals. We spend vast sums to
manage our health, and we pop pills to address every conceivable symptom.
Some elderly Americans take as many as 30 drugs a day, some of them merely
to counteract the effects of others. Prescription drug sales rose by an
annual average of 11 percent between 2000 and 2005. Americans now fill
more than three billion prescriptions a year; nationwide, more than 10
million women take birth-control pills, and about the same number are on
hormone-replacement therapy.
The rate at which prescriptions are dispensed is only going up as the
population ages. Already, those over 65 fill twice as many prescriptions
per year as do younger Americans. Inevitably, more drugs will be headed
into waterways like the Pomperaug. Our rivers -- already stressed by
pollutants, groundwater pumping, reduced flows, and overburdened
wastewater treatment plants that dump raw sewage -- will be ever less able
to cope.
Alarmed by data that showed trace levels of pharmaceuticals in European
streams, researchers in the United States have begun to survey our
nation's waterways. In 2002, the USGS published the results of its
first-ever reconnaissance of man-made contaminants. Using highly sensitive
assays, the agency found traces of 82 different organic contaminants --
fertilizers and flame retardants as well as pharmaceuticals -- in surface
waters across the nation. These drugs included natural and synthetic
hormones, antibiotics, antihypertensives, painkillers, and
antidepressants.
Now that science has documented the presence of free-flowing
pharmaceuticals, researchers are faced with another, far more difficult,
pair of questions: What does this mean for the environment, and what does
it mean for us? Early evidence of harm to aquatic organisms is giving
researchers grounds for real concern.
On a dull November morning, two graduate students from the University of
Connecticut shiver on the steep banks of the Pomperaug. Monotonously,
repetitively, they plunge plastic jars two feet down into the beer-colored
water. Five-minute intervals tick away on a stopwatch. "Is it here yet?"
asks Dan Seremet. He's now midstream, his fleece cuffs dripping onto his
chest waders. Raquel Figueroa, squatting in a drift of crisp oak leaves,
slips a vial of water into a portable fluorometer, closes the gizmo's
cover, taps a button, and answers, "Point one nine."
So, no. It isn't here yet.
Five minutes pass, Raquel shouts in her tiny voice, "Go!" and Dan,
maneuvering over slippery rocks, dips his jar again. Two hours pass, in
five-minute chunks, and the fluorometer, which detects and measures
specific particles in the water, rises only to 0.65 parts per billion
(ppb).
"Maybe we're in the wrong river," Dan sighs. Raquel doesn't bother to
answer. She logs the time and the concentrations. She dumps out samples.
She painstakingly removes a bittersweet vine holding her leg prisoner.
"Next time we should bring pruners," she says to no one in particular.
Then, "Go!" Dan dips.
In 30 minutes, the fluorometer rises to 2.45. Nothing to get excited
about: When the half cup of fluorescent magenta dye -- poured into the
Pomperaug two miles upstream and two hours earlier -- flowed past the
previous monitoring station, the reading peaked at just over 4 ppb.
"Uh-oh," says Raquel when she takes the next reading. "We're down to
2.301." In another five minutes it is 2.25.
"I guess that was the peak," says Dan, his voice the opposite of a peak,
as he clambers out of the streambed. He and Raquel pack up their bottles
and log books, the fluorometer, a tape measure, and a flow meter
(basically a pair of spinning blades on a stick, used to measure the
water's velocity), then drive downstream to do it all again with the boss,
at the last of four monitoring stations.
The boss is Allison MacKay, an environmental engineer who specializes in
aquatic chemistry at the University of Connecticut. MacKay had risen at
four o'clock in the morning and loaded her car with gear, plus the sleepy
Dan and Raquel, then drove west to Southbury. By eight, she had poured her
dye into the Pomperaug at the point where it receives the Heritage Village
effluent. (Invisible to the naked eye, the dye is nontoxic and will
degrade in sunlight over three days.) With her grad students MacKay is
tracking the dye's progress down a six-mile stretch. The concentration of
the dye, read by the fluorometer, will tell her both the rate at which the
Pomperaug flows and the rate at which a particular contaminant is diluted
as it flows downstream -- two useful bits of information when you're
studying the movement of contaminants from a single source. MacKay and her
helpers are also taking water samples that will later be analyzed for the
presence of the same 82 organic contaminants originally assayed by the
USGS.
In a turquoise parka and insulated pants, MacKay kneels on the sandy bank.
Her cheeks are pink in the cold air. If there is any fun to be had along a
New England river in November, this crew refuses to acknowledge it. There
are no observations on flora or fauna, no chitchat, no stone skipping or
stick building. MacKay is all business, and her students follow her lead.
For eight hours (no lunch break) they collect water and measure the
river's depth, width, and velocity.
"The USGS does grab
samples," says MacKay, rapidly punching a series of numbers into her
calculator and plotting points on a hand-drawn graph. Grab samples are
like snapshots, a single moment in a single place in a stream. "Their
studies established the presence of drugs in our waterways, but no one in
this country has looked at the temporal and spatial distribution or the
environmental degradation rates of pharmaceuticals in surface water.
That's what I'm doing." Among the factors that influence the compounds'
fate are sunlight, temperature, flow rate, microorganisms in the sediment,
minerals, and other chemicals in the water. If concentrations of any
particular contaminant decrease, MacKay explains, she'll set up controlled
lab experiments to see where, when, and how it happened: Was it the sun
degrading the compound, a change in temperature, or an organism that might
have consumed it? If aquatic life is suffering, she continues, researchers
will need to know what concentrations they're being exposed to at
different points in the stream.
This stretch of the Pomperaug makes an ideal laboratory for MacKay's
study: It is wadeable, and it has only one significant input of both water
and prescription compounds -- the Heritage Village treatment plant. The
river is also a paradigm of the nation's threatened waterways, of the
large- and small-scale changes that our growing population has wrought.
Still, to drive the country roads of Southbury and its neighboring
villages is to marvel at what hasn't changed in the past 200 years.
Well-kept colonial houses still flank water mills; nineteenth-century farm
fences decorously sag. The stream banks are, for the most part, intact.
Trout congregate in deep pools. Though some of its meanders and oxbows
were mechanically straightened more than half a century ago, the river
still flows past horse farms and hemlock glades and rolling hills.
One can't help thinking
the Pomperaug is privileged to run through a stronghold of the well-to-do.
All American rivers are, at some level, endangered, but this one's
remaining virtues are particularly obvious. Not only is there plenty worth
saving here, there are also plenty of stakeholders eager to do the saving,
among them a mild-mannered, semiretired internist named Marc Taylor, who
happens to live just a few miles downstream from MacKay's sampling sites.
Taylor is the medical director of the River Glen Health Care Center, where
Patricia Reilly lives, but he spends an inordinate amount of time fretting
-- in public meetings and in private telephone calls with scientists,
politicians, city planners, and conservation groups -- about the health of
his river. "I'm concerned about pharmaceuticals in the river because I am
a doctor," says Taylor, who speaks in precisely measured sentences, "and
because I know these drugs are bioactive." That is, they can enter the
bioprocesses of aquatic organisms.
As chairman of the
Pomperaug River Watershed Coalition, Taylor has watched with increasing
concern as developers cut streets into nearby hillsides, shopping centers
supplant farms and orchards, and waves of the elderly flock to four
planned communities within the town limits. "As the population of the
watershed goes up," says Taylor, sitting in his basement office surrounded
by maps of the region, "more groundwater is being pumped. We've got three
public water companies drawing water from wells sunk near the Pomperaug."
With a few computer keystrokes, Taylor pulls up real-time data from a
gauging station on the river. This afternoon's flow is 250 cubic feet per
second. Last summer it dropped to 8 cubic feet per second -- one of the
lowest flow rates in the river's recorded history. Some small streams in
the Pomperaug watershed now completely disappear in the summer.
The Pomperaug's peril is not unique. "Across the nation rivers are
stressed," says Katherine Baer, advocacy director for American Rivers,
which is based in Washington, D.C. "As drought becomes more common, there
is less water in streams for aquatic life. Everywhere we see more
development, sprawl, and increased population. So we get higher pollution
loads. Pharmaceuticals, which become more concentrated with low water, are
only increasing the burden."
At the present time, in a project unrelated to its study of contaminants,
the USGS is making hydrologic models of how water enters, moves through,
and leaves the Pomperaug watershed. The Pomperaug River Watershed
Coalition is studying water quality, the dilution of treated wastewater,
and, with the help of Allison MacKay, the environmental fate of compounds
left behind after drugs have been metabolized by our bodies, as well as
that portion of the drugs that passes through us without being absorbed.
According to the Environmental Protection Agency, which is putting
together a database of literature on so-called emerging contaminants,
those metabolites are virtually everywhere, from the iconically dirty
Chicago River to the iconically pristine headwaters of Boulder Creek in
Colorado. They're in the intakes and outflows of water facilities in both
urban and rural areas, in groundwater, mountain streams, surface water,
and domestic wells. And while levels of pharmaceuticals are sometimes
infinitesimally low, their supplies are continually replenished. As a
result, organisms that constantly bathe in a chemical broth are beginning
to reveal some alarming abnormalities.
In Boulder Creek, David Norris, an environmental endocrinologist at the
University of Colorado at Boulder, found that female white suckers,
bottom-feeding fish that grow up to a foot long, outnumber males by more
than five to one, and that 50 percent of males have female sex tissue.
Similar intersex changes have been found in flat- head chubs and
smallmouth bass. The cause, Norris suspects, is exposure to estrogen. Like
most pharmaceuticals, hormones aren't designed to break down easily.
They're supposed to have an effect at low dosages with chronic use, and
they only partly dissolve in water.
"I'm worried for fish
populations, and I'm worried for human populations," says Norris. "The
levels found in Boulder Creek are low in absolute terms, but they aren't
low on the biological level. You could have six chemicals below the
no-effect level, but all together they are above the no-effect level." In
lab tests, frogs and rats have developed infections and deformities after
being exposed to multiple pollutants at extremely low levels. Since
exposure to only one compound is rare in the modern world, sorting out
"mixture effects" is a daunting but critical research area. The estrogenic
compounds in drinking water, Norris says, are "adding to the general
exposure of the human population to environmental estrogens in our foods,
and in containers that hold our foods. They all work through the same
mechanisms." In the United Kingdom, hormones in the environment have been
linked with lowered sperm counts and gynecomastia -- the development of
breasts in men.
A Baylor University researcher found tiny amounts of Prozac in liver and
brain tissue of channel catfish and black crappie captured in a creek near
Dallas that receives almost all of its flow from a wastewater treatment
plant. The creek also connects to a drinking water supply. A University of
Georgia scientist found that tadpoles exposed to Prozac morphed into
undersize frogs, which are vulnerable to predation and environmental
stress. The EPA reports that antidepressants can have a profound effect on
spawning and other behaviors in shellfish and that calcium-channel
blockers (used to relieve chest pain and hypertension) can dramatically
inhibit sperm activity in some aquatic organisms. Even at extremely low
levels, ibuprofen, steroids, and antifibrotics -- a class of drugs that
helps reduce the development of scar tissue -- block fin regeneration in
fish. According to a report by the Scientific Committee on Problems of the
Environment, a worldwide network of scientists and scientific
institutions, and the International Union of Pure and Applied Chemistry,
more than 200 species -- aquatic and terrestrial -- are known or suspected
to have experienced adverse reactions to such endocrine disruptors as
estrogen and its synthetic mimics.
Experts say pharmaceuticals have probably been in the environment for as
long as we've been using them. We're discovering them now because
analytical methods sensitive at the parts-per-trillion level and lower
were only recently developed. Surely the technology is a boon to society,
but it opens a Pandora's box of questions. We know that low concentrations
of some pharmaceuticals are affecting aquatic organisms, but what are they
doing to humans? What happens when organisms are exposed to multiple
chemicals at the same time? What happens when they bioconcentrate in
living creatures or accumulate in sediment?
Traditionally, toxicologists have assessed environmental and health risks
one chemical at a time, focusing on such end points as birth defects or
cancer. More recently, scientists have begun to examine effects from
combinations of chemicals, an approach that more closely mimics the way
organisms are exposed to chemicals in the environment. Looking at end
points that include immune and reproductive system dysfunctions and
neurological, cognitive, and behavioral effects, researchers are finding
that mixtures of chemicals can lead to effects at much lower levels than
do single chemicals, and that low-level exposure can often induce results
not seen at higher levels. Nearly every week, results of new studies on
emerging contaminants appear in toxicology and environmental health
journals.
"It may seem impossible to figure out what's happening," says
Christian Daughton, chief of the environmental chemistry branch of the
EPA's National Exposure Research Laboratory in Las Vegas, "but technology
has a way of leapfrogging. Less than a decade ago no one thought you could
map the human genome. Analytical chemistry progresses at a fast rate.
Remember, we're only talking about this now because we developed the
technology to find these compounds."
Elizabeth Royte, a regular contributor to
OnEarth,
is the author of :
Garbage Land: On the Secret Trail of Trash
(Little, Brown).
OnEarth. Fall 2006
Natural Resources Defense Council
www.nrdc.org
Click
here to view
The National Resource Defense Council
In the
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