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You
are what you ate, breathed, drank and more
By Francesca Lyman
Feb. 5 — Two recent studies cast dramatic light on the extent
to which Americans are absorbing toxic chemicals in their bodies
as part of everyday life. They present a striking picture of Americans
riddled with low levels of chemicals, the vestiges of eating, drinking,
breathing and touching the synthetic products of the industrial
world. Given how common these chemicals are, can personal actions
and better choices reduce one’s level of exposure in a toxic
world?
Charlotte
Brody used to think so. For 20 years, she ate organic produce and
followed all the usual recommendations to reduce chemical exposure,
from using non-toxic household cleaning detergents to avoiding pesticides
in her home and garden.
Joking that she washed her bathtub in vinegar so much that her family
said it smelled like a salad, she adds, “I’m the one
hand-picking individual weeds from my garden rather than using chemical
sprays, and going that extra mile to get my organic milk in a glass
bottle.”
With
more than 70,000 chemicals in use in the United States and 2,000
new compounds being introduced every year, according to government
figures, the average American is exposed to a cocktail of chemicals
from various sources.
Brody
used to think her efforts helped limit her exposure, but after volunteering
to take part in a study measuring toxic chemicals in her body, she
was shocked to find that she still had some 85 toxic chemicals in
her blood and urine.
“I’m
proof that a healthy lifestyle doesn’t shield you,”
says Brody.
A
chemical cocktail
Brody and eight other volunteers were tested for the presence of
210 chemicals, commonly found in consumer products and industrial
pollutants, by the Mt. Sinai School of Medicine in New York and
two non profit groups, the Environmental Working Group and Commonweal.
The
study claims to be “the most comprehensive” survey to
date of the multitude of contaminants found in humans.
Tests on blood and urine detected an average of 91 industrial compounds,
pollutants and other chemicals in the volunteers, with a total of
167 chemicals found across the entire group. The researchers chose
subjects who did not work with chemicals in their jobs or live in
industrial areas.
This
small Mt. Sinai study and a much more comprehensive survey done
by the Centers for Disease Control, also released in January, shed
new understanding on the “body burden” of toxic chemicals
we all carry inside. The results illustrate a side effect of modern
life in which everything from carpets to cosmetics are bathed in
toxins.
Biomonitoring
our bodies
The Centers for Disease Control and Prevention have embraced "biomonitoring."
The technology allows researchers to measure chemicals directly
in blood and urine rather than having to rely on exposure estimates
based on air, water or soil samples. Click on a category for recent
biomonitoring breakthroughs.
CDC
and Danish researchers found that the risk of breast cancer significantly
increased with increasing levels of dieldrin, a pesticide, in women's
blood. This result suggests that exposure to dieldrin and other
"organochlorine" compounds may increase the risk of breast
cancer.
Methyl
parathion, a pesticide that should never be used indoors, has been
found inside thousands of homes in at least seven states and led
to the deaths of two children in Mississippi. In response, the CDC's
Environmental Health Lab developed a method to measure methyl parathion
in urine and did so in more than 15,000 people. The results helped
identify who needed treatment and who needed to be moved out of
their homes until the homes could be cleaned.
Trihalomethanes,
chemicals that evaporate easily into the air, are thought to be
linked to birth defects, bladder cancer, and colorectal cancer.
Formed during the water sanitation process, they are often found
in drinking water. The CDC's lab developed a way to measure trihalomethanes
in blood, and it's being used in studies to find out how much enters
people's bodies and whether the chemicals are causing illness.
The
CDC's lab developed ways to measure cotinine -- a chemical formed
by the breakdown of cigarette nicotine in the body -- in saliva,
blood, and urine. These methods are being used to find out: how
much secondhand smoke is getting into children, adolescents and
adults; what levels of chemicals in tobacco smoke cause health problems;
how well actions to protect people from secondhand smoke are working;
and how well actions to help smokers stop smoking are working.
Results
of CDC study
The CDC tests measured some 116 harmful chemicals, including lead,
mercury and other heavy metals, chlorinated solvents, insecticides
and other pesticides, PCBs, and plasticizing agents called phthalates,
to name but a few.
The agency noted some public health successes, such as a decline
in lead levels and in cotinine, the byproduct of tobacco smoke.
But the researchers also announced some troubling findings, including:
- Children
have twice the levels of certain pesticides in their blood as
adults
- Children
have higher levels of cotinine than adults
-
Children have higher levels of certain chemicals used in soft
plastic toys
-
Adolescents have high levels of phthalates from personal care
products
-
Mexican-Americans have three times the levels of the banned pesticide
DDT in their systems as other Americans
Cause
for concern?
Environmentalists interpreted the test results as greater evidence
of the need for better regulation of industrial chemicals, while
some in the chemical industry saw them as a sign that better regulations
and detection methods are working well.
“Just
because chemicals are found present in the body doesn’t mean
there’s cause for concern, but only that an internal metabolic
process has occurred,” said Jennifer Biancaniello, a spokesperson
for the American Chemical Council, a trade association of chemical
manufacturers. “CDC hasn’t come out and said there’s
cause for health concern.”
While
the CDC researchers did not comment on the possible health consequences,
they did note that there are not enough studies available to adequately
answer health questions regarding most of the chemicals found.
The
report’s immediate value, CDC officials said, was to show
for the first time the extent of Americans’ exposure to a
range of ubiquitous chemicals.
With
data on real-world “body burdens,” researchers can then
monitor the same populations for health effects and begin to connect
the dots between exposures and health outcomes, said Jim Pirkle,
deputy director for Science at the CDC’s environmental health
laboratory.
“The
important thing is to look at this as a work in progress,”
said Dr. David Fleming, the deputy director of the CDC. “We’re
getting information we never had before. Better decisions can be
made about how to protect people from environmental hazards.”
Making
personal choices
According to the Mt. Sinai study, chemicals make their way into
our bodies through pollution, food additives, pesticide residues,
a range of consumer products from paints and plastics, and a wide
array of building materials.
Given the ubiquitous nature of these chemicals, can individual actions
to reduce one’s exposure make a difference?
“People
should stop smoking and stop exposing children to secondhand smoke,”
said the CDC’s Pirkle, who also cited the need to avoid lead
in paint and other products. “But there’s no way you
can get rid of everything,” he adds.
Kris
Thayer, a scientist with the Environmental Working Group and one
of their study’s authors, points to new evidence showing that
making simple dietary changes can reduce one’s exposure. She
cites a recent study that found feeding children organic food reduced
their exposures to pesticides by 6 to 9 times and another study
that found cutting consumption of fish decreased blood levels of
methyl mercury, a potent neurotoxin.
But
many exposures to toxic chemicals in daily life are unavoidable,
she says. She hopes body testing will spur governments and corporate
leaders to reduce toxic emissions and even ban some products, as
Sweden recently did when it found traces of fire retardant turning
up in women’s breast milk.
Rather than be paralyzed by our toxic exposure, we ought to use
the results of these studies to promote better policies and product
lines, said Jeannie Rizzo, director of the Breast Cancer Fund.
“I
would have liked CDC to call for more policy changes and make a
more urgent call for research,” said Rizzo. “We’re
walking around with these chemicals in us but with a process (for
protecting us) that doesn’t have to be this slow.”
How
do you know which substances to avoid? Toxic chemicals with particularly
powerful effects include heavy metals, organic solvents and pesticides.
Endocrine-disrupting chemicals such as dioxin, PCBs and phthalates
-- substances that leach out of plastic packaging and wraps -- may
also be harmful to your health. |