[Pharmwaste] Rivers of Doubt - Minute quantities of everyday contaminants in our drinking supply could add up to big trouble

DeBiasi,Deborah dldebiasi at deq.virginia.gov
Wed May 30 10:24:25 EDT 2007


URL: http://www.msnbc.msn.com/id/18881799/site/newsweek/page/0/

Rivers of Doubt 

Minute quantities of everyday contaminants in our drinking supply could
add up to big trouble.

By Anne Underwood

Newsweek
June 4, 2007 issue - U.S.A.

Population: 300 million
Problem: Emerging contaminants
Up to his knees: Schoenfuss captures fish for study in the Grindstone
River near Hinckley, Minn., looking for chemicals that mimic hormones

The common white sucker is nobody's favorite fish. It's a bottom feeder
that trout fishermen in Colorado happily toss back into the water. But
it's also what scientists call a sentinel-a species whose health (or
lack thereof) can warn us about problems in the environment. So imagine
the reaction of environmental endocrinologist David O. Norris of the
University of Colorado when he discovered some alarming changes in the
sucker population of Boulder Creek. Upstream, where the water flows pure
and clear out of the Rocky Mountains, the ratio of males to females is
50-50, just as nature intended. Downstream, below the
wastewater-treatment plant in Boulder, the females outnumber the males
by 5 to 1. Even more worrisome, Norris found that about 10 percent of
the fish were neither clearly male nor female, but had sexual
characteristics of both. "On the one hand, we were excited [to make such
a dramatic finding]," says Norris. "At the same time, we were appalled."

There's something fishy in the nation's water supply. True, its quality
has improved dramatically since passage of the Clean Water Act in the
1970s. Toxic substances and pollutants are now routinely filtered out.
But across the nation, something's causing disturbing effects on aquatic
wildlife. In a search for culprits, scientists are zeroing in on a group
of compounds they call "emerging contaminants," including
pharmaceuticals, cosmetics and antibacterial soaps. Although we like to
think that these compounds disappear when we wash them down the drain or
flush them down the toilet, a lot of them are clearly ending up in
water. Could they possibly affect human health? At this point, no one
knows for sure. "We have lots of questions, but very few answers," says
environmental chemist Christian Daughton at the Environmental Protection
Agency.

Scientists aren't worried about any one of these chemicals in isolation.
Most are found in minute doses, if they're found at all. Toxicologist
Amy Perbeck at the Michigan Department of Environmental Quality
calculated that the levels of ibuprofen in Michigan drinking water were
so low that a person would have to consume 17,000 gallons to get the
amount in one pill. But new technology is allowing scientists to screen
for mere traces of compounds, down to levels that were previously
undetectable-and they find just about everything they look for. A 2002
study by the U.S. Geological Survey detected such compounds in 80
percent of the 139 streams it examined, many of which were downstream
from urban areas. None of the chemicals on its own appears to be toxic
at minuscule doses. "But what happens when a person is exposed to a
whole cocktail of them?" asks Perbeck.


The emerging compounds of greatest concern to most scientists are the
"endocrine disrupters." These are chemicals in the environment that
mimic hormones when they get into the body. An astonishing array of
chemicals fall into this category-not only natural and synthetic
hormones, but also chemicals in certain cosmetics, shampoos, shaving
lotions, skin creams, dishwashing liquids, pesticides, flame retardants,
plastics and antibacterial soaps. Like actual hormones, "they have
effects at exceedingly low levels," says Herb Buxton, coordinator of the
Toxic Substances Hydrology Program at the USGS. Because so many of them
bind to a certain type of receptor in the body-whether for estrogens,
androgens or thyroid hormones-the effects add up.

Judging by fish populations, the result isn't good. Scientists have
found "feminized" male fish in the Mississippi, Ohio, Allegheny,
Monongahela, Shenandoah and Potomac rivers. Unlike the abnormal Boulder
Creek fish, which had both ovaries and testes, most of these fish are
clearly males. But their testes contain some ovarian tissue that
produces immature eggs, and their livers are producing egg-yolk
proteins. In lab studies, scientists have also shown that male fish
exposed to estrogenic compounds during early development have lower
sperm counts and worrisome behavioral changes. In one experiment, Heiko
Schoenfuss, head of the aquatic-toxicology lab at St. Cloud State
University in Minnesota, exposed male fathead minnows early in life to
estrogenic chemicals called alkylphenols (which come from some common
industrial and household cleaners)-and discovered that as adults, they
failed to defend their territory. The result? They were unable to
reproduce successfully because they allowed other males to invade their
nesting areas and eat their offspring.

Put it all together, and scientists worry that endocrine disrupters
could cause declines in fish populations. In a paper last week in the
Proceedings of the National Academy of Sciences, a team of Canadian and
American scientists reported the collapse of the fathead-minnow
population in a Canadian test lake after low levels of a potent
synthetic estrogen were intentionally introduced. In the first year,
researchers saw the same kind of feminization of male fish observed in
the United States. The next year, says lead author Karen Kidd of the
University of New Brunswick, they documented the "near extinction of
this species from the lake."



People, thankfully, are less vulnerable than fish, because we don't live
and breathe in water. To date, there is no conclusive evidence linking
emerging contaminants to human health problems. But scientists wonder if
endocrine disrupters in the water are partially responsible for some
well-documented trends, including earlier puberty in girls and reduced
sperm counts in men. In fish, sperm problems have been linked to
waterborne contaminants, including phthalates, which are used in many
plastics, cosmetics, skin-care products and pesticides. Reproductive
epidemiologist Russ Hauser at Harvard has found an association in men
between certain phthalates in their urine and low sperm counts-although
he notes that there are multiple routes of exposure in people, including
direct absorption through the skin from after-shaves and colognes. Water
is only one of many sources. As Devra Lee Davis, director of the
University of Pittsburgh's Center for Environmental Oncology, sees it,
humans are exposed to so many things over a lifetime that it's hard to
prove connections-but problems in wildlife should be a warning. "We have
to stop treating people like lab rats in an uncontrolled experiment and
start figuring out ways to reduce our exposures," she says.

So how can we keep these chemicals out of the water supply? No one is
suggesting that we give up medicines or mascara. There are, however, a
few commonsense measures we could take. Look for phthalate-free
deodorants and body lotions. The Environmental Working Group has a list
on its Web site. Stop using antibacterial soaps. Numerous studies have
found that washing with regular soap is just as effective. And learn how
to dispose of drugs properly. Most shouldn't be flushed. Some
municipalities will even dispose of them along with hazardous waste.

If you're truly worried about drinking water, the answer isn't bottled
water, which in many cases is just bottled tap water-and requires large
amounts of energy to transport. Consumer devices for removing
contaminants include charcoal filters, tabletop water distillers and
purification units that use reverse osmosis. They can all take out a
wide variety of chemicals. The fish should be so lucky.

URL: http://www.msnbc.msn.com/id/18881799/site/newsweek/page/0/


------------------------------------------------------------------------
--------

MSN Privacy . Legal
(c) 2007 MSNBC.com 


Deborah L. DeBiasi
Email:   dldebiasi at deq.virginia.gov
WEB site address:  www.deq.virginia.gov
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
Mail:          P.O. Box 1105, Richmond, VA  23218 (NEW!)
Location:  629 E. Main Street, Richmond, VA  23219
PH:         804-698-4028
FAX:      804-698-4032



More information about the Pharmwaste mailing list