[Pharmwaste] Female Troubles for Wildlife Raise Human Worries

[DeBiasi,Deborah]

Run Date: 12/18/06 
By Molly M. Ginty
WeNews correspondent 


Across the U.S., female animals exposed to toxic chemicals are suffering
from a flurry of health problems. As scientists examine the impact of
environmental pollution, some are pondering what the results may mean to
female humans. First of two parts.
 

(WOMENSENEWS)--In California, female sea lions are spontaneously
aborting their fetuses.

In the Great Lakes area, mother gulls are sharing nests and raising eggs
together because their male partners have forgotten how to parent.

In upstate New York, female frogs have as much testosterone in their
bodies as males.

Scientists say these aberrations all share a common link: exposure to
toxic chemicals called "endocrine disruptors," which pollute the air,
soil and water.

"At the rate this pollution is going, we will likely have population
decreases in many wildlife species, especially amphibians and fish that
are more susceptible to toxins because their skin is constantly exposed
to these chemicals in an aquatic environment," says Sarah Janssen, a
science fellow at the New York-based Natural Resources Defense Council.
"These animals serve as canaries in the coal mine for human females,
teaching us how synthetic chemicals might affect our nervous system
development, immune function, fertility and other health outcomes."

In the past six decades, U.S. manufacturers have unleashed an estimated
100,000 synthetic compounds into the environment.

When animals come into contact with these pollutants, which have been
detected in rainwater and in the rivers and soil of even the most remote
areas, they absorb synthetic chemicals into their bloodstreams and their
bodies. Researchers are finding that the female halves of many species
are displaying biological reactions.

Earthworms Dosed With Prozac
Synthetic compounds have been detected in even the simplest life forms.
According to a 2006 study by the U.S. Geological Survey (USGS),
earthworms now have an average 31 pollutants in their bodies, including
perfumes, household disinfectants and the antidepressant Prozac.

"As you go up the food chain, the numbers or relative amounts of
synthetic chemicals can be even higher," says Diana Papoulias, a USGS
biologist in Columbia, Mo. "Mammals, in particular females, have more
fat in their bodies than other animals and therefore can have more
toxins in their fat."

Years after they were created and put into common use, many synthetic
chemicals were found to be endocrine disruptors, which means they
interfere with the action of hormones that regulate animals' growth,
development and fertility. These chemicals are of particular concern to
female animals, since their hormones, like those of human females,
fluctuate more than those of males.

Common endocrine disruptors include pesticides, phthalates (which make
plastic flexible and make cosmetics adhere to the skin) and
polychlorinated biphenyls (PCBs, industrial cooling agents banned in the
United States in 1979 but still present in the environment.) Individual
chemicals such as these--or groups of them working together--are making
animals' hormones go haywire.

In Washington state, endocrine disruptors have been tied to the deaths
of mother orcas, whose orphans have been adopted by other female whales.

 
In Alaska, they have caused female polar bears' ovaries to shrink.

In Massachusetts, they have lowered the over-winter survival rates of
female tree swallows.

In Florida, they have accumulated in the milk of mother dolphins,
poisoning and killing their calves.

In addition to harming female animals, endocrine disruptors can cause
the "feminization" of males. In Arizona, these chemicals have shrunken
the gonads of largemouth bass and common carp. In the Midwest, they have
spurred male waterfowl to grow female organs. In Washington, D.C., they
have caused male fish to produce eggs.

Small Amounts, Big Impact
Just as alarming as these problems is the low level of exposure at which
they are occurring. When Tyrone Hayes, an assistant professor of biology
at the University of California, Berkeley, studied the
endocrine-disrupting properties of atrazine, a common weed killer, he
discovered reproductive abnormalities in affected leopard frogs at 0.1
parts per billion parts water, 30 times less than the Environmental
Protection Agency's limit for atrazine in drinking water.

Though proof that endocrine disruptors can harm female wildlife is
mounting, scientists say it is difficult to assess the total damage.

"In the wild, subtle outcomes such as length of gestation, litter size
and the age of onset of puberty are difficult to ascertain," says
Janssen. "You would have to know exactly when these females became
pregnant and gave birth. You would have to anesthetize them to take
blood samples. You would have to carefully observe and measure life
events that are difficult to track in the field. Measuring these effects
would ideally involve more controlled studies."

In laboratory settings, studies have repeatedly shown the adverse
effects of some of the most prevalent endocrine disruptors.

Consider phthalates, those chemicals that help prevent makeup from
smudging. In 2003, an Environmental Protection Agency study found these
substances could reduce fertility in rodents, causing female rats to
bear 50 to 90 percent fewer offspring.

Take bisphenol-A, a compound used to make everything from computer
keyboards to dental sealants to food-can lining. A 2005 study by the
National Institute of Environmental Health Sciences in Research Triangle
Park, N.C., found that exposure to this chemical can spur obesity in
female rats. In August 2006, researchers at Tufts University in Boston
found it can also cause breast cancer in female rodents.

There's also dioxin, a byproduct of paper manufacture and waste
incineration. In 1998, researchers at the Washington-based Environmental
Protection Agency found this chemical could trigger spontaneous
abortions in rhesus monkeys. In 2003, a University of Ottawa study found
it could also cause female primates to develop endometriosis, a disease
that causes endometrial tissue normally found in the uterus to grow
outside the womb.

More Questions Than Answers
As lab studies on endocrine disruptors continue, questions about what's
happening in the wild persist. Why are mother sea ducks in Alaska
producing fewer offspring? What's causing female dolphins in the
Southeast to develop tumors in their reproductive tracts? Why are loon
hatchlings in Wisconsin emerging deformed from their eggs?

Since only 10 percent of the synthetic chemicals in our environment have
been tested on animals, scientists have yet to offer answers to these
questions.

While research continues, some environmental advocates recommend that
women avoid consuming fish and meat from the wild (such as carp caught
in rivers or deer or pheasant shot by hunters) to avoid ingesting
endocrine disruptors found in these animals' bodies.

Others recommend political action: calling for reduced emissions of
synthetic chemicals, and calling on the Environmental Protection Agency
to beef up its study of endocrine disruptors, a step Congress mandated
in 1996 but one that the EPA has yet to take because it says setting up
the research is proving more difficult than expected.

Because these chemicals also surround people, concern is building about
their effect on humans.

"Animals don't use computers, apply makeup or use chemical solvents in
their homes every day," says Theo Colborn, former director of the
Wildlife and Contaminants Program at the Washington-based World Wildlife
Fund. "In the end, female humans may be at even greater risk than female
animals."

On Dec. 19, Women's eNews will run the second of this series, looking at
the efforts taken to study the effects of these toxins on women.

Molly M. Ginty is a freelance writer based in New York City.

 

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