By Thaddeus Herrick
Last winter, Sharyle Patton got some startling medical-test results.
But she's unsure what, if anything, they mean.
The 59-year-old environmental activist lives in a rural California
community far from industrial centers. She eats organic food and
to bike and walk as much as drive. Yet a screen of her blood and
showed that her body carried 105 chemicals in measurable levels,
including 46 different compounds of PCBs, industrial insulators
were banned in 1976.
Ms. Patton was part of small study testing subjects for the presence
industrial chemicals. Such research is part of a burgeoning movement
called "biomonitoring," an effort to determine the extent
exposure to synthetic chemicals, and to link these pollutants
diseases such as breast cancer.
It has become an integral part of public-health research in Europe,
where some countries routinely screen citizens for industrial
In 1998, studies of Swedish breast milk showed that levels of
retardants known as polybrominated diphenyl ethers, or PBDEs,
doubling every two to five years. As a result, Sweden banned PBDEs,
the EU has followed suit beginning this year.
Some research here in the U.S. has come up with disturbing numbers.
study of 20 first-time mothers commissioned by the Washington-based
Environmental Working Group, released in September, found considerably
higher PBDE levels in U.S. women than those recorded in Sweden.
Still, little is known about the implications of these chemicals,
research subjects who are told they have a high "chemical
are unsure what to do about it.
One worry is that the findings will have their own side effects.
Breast-feeding advocates fear that reports of chemicals being
breast milk could discourage breast-feeding -- even though the
for Disease Control and Prevention says it has yet to see levels
chemicals in breast milk that would lead it to discourage
The San Francisco advocacy group Breast Cancer Action withdrew
support of a California legislative bill last year to monitor
in mother's milk, citing worries about the effect on breast-feeding.
The move put it at odds with its longtime ally, the Breast Cancer
which supports biomonitoring. The bill is expected to be reintroduced
Right now, commercial laboratories don't generally offer such
which would have to be custom-designed. And research projects
and expensive. The study Ms. Patton participated in, organized
advocacy groups Environmental Working Group and Commonweal, with
Sinai School of Medicine, cost researchers $4,900 per person.
then, the studies don't always share results with participants.
In Ms. Patton's study, in which researchers did agree to share
findings, an average of 91 industrial chemicals were found in
adults from six states, with a total of 167 different chemicals
reported in the group. Yet few of the subjects have made many
adjustments. Ms. Patton has lived in Bolinas, Calif., north of
Francisco, for some 30 years and says she felt she was living
life. She has, however, given up nail polish because it often
phthalates, chemicals used for their plasticizing and film-formation
"I'm outraged," she says. "I never gave permission
to use my body as a
toxic waste site."
There are many ways that chemicals can get into the body. Mostly
through diet or environmental exposure.
For example, PBDEs are used in foam for furniture, among other
As the foam breaks down, PBDEs are thought to leach into the air
Are then carried by the wind, rain and snow around the world.
The U.S. Environmental Protection Agency is funding local studies
breast milk in 120 women in three California communities to look
levels of PBDEs, and other chemicals. This year, the CDC released
most exhaustive biomonitoring survey yet, an attempt to compile
baseline for future efforts to identify and treat victims of exposure
to toxic chemicals. The $6.5 million study tested the blood and
urine of 2,500 anonymous volunteers for 116 chemicals, with positive
found for 89 substances, including polychlorinated biphenyls,
dioxins, phthalates and pesticides. A follow-up is expected in
"We plan to be in it for a long, long time," says Jim
director for science at the CDC's Environmental Health Laboratory.
A few of the chemicals for which CDC tested -- including lead,
cadmium, mercury and some pesticides -- are known to be toxic
people; researchers found levels of lead and nicotine-related
chemicals sharply reduced over the past decade. Many more of the
chemicals in the study have been found to be toxic to laboratory
developmental or reproductive problems, or even cancer. But their
effect on humans is still something of a guessing game. "We've
got to expand our understanding," says Dr. Pirkle.
The larger goal is to see if there are links between industrial
chemicals and an array of ailments in human beings. In part because
chemicals often accumulate in the fatty tissue of breasts, as
breast milk, biomonitoring has won particular support from
breast-cancer advocacy groups, despite Breast Cancer Action's
reservations. With as many as half of the breast-cancer cases
unexplained, they see biomonitoring as an alternative to the traditional
focus of detection, treatment and cure.
"It's an essential part of the research movement,"
says Jeanne Rizzo,
executive director of the Breast Cancer Fund.
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