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Our bodies, our landfills? |
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You are what you ate, breathed, drank and more |
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By Francesca Lyman
MSNBC CONTRIBUTOR |
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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? |
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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.
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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.
Breast Cancer
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.
Children &
Pesticide
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.
Drinking Water
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.
Cigarette Smoke
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.
Source: Centers for Disease Control and Prevention
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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:
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.”
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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.
Lead
High levels of
exposure linked to infertility in males and spontaneous abortion in
women. New evidence suggests that low exposures also may have
serious health effects. Since lead crosses into the fetal brain,
there may be long-term effects on behavior and intelligence, for
example.Major sources: old house paint; exterior paint on old steel
structures such as bridges and railways; lead-soldered faucets.
Mercury
Toxic to the
developing brain, mercury is a known cause of birth defects and
severe neurological effects. The most dangerous form is organic
mercury: It is most easily absorbed and thus can cross the placenta
and make its way into the developing fetus. Contaminated fish,
particularly fish-eating fish like swordfish, tuna, shark and pike,
are major food sources for humans. Mercury can also be inhaled, as
it is a contaminant in coal and oil burning, chlorine manufacture
and waste incineration.
Manganese
Manganese, abundant in nature, is an essential mineral at low doses.
But at high levels, it is toxic to the brain and lungs. It may also
interfere with human hormones and damage male fertility and
reproduction. At high levels, manganese also appears to disrupt
fetal development; high levels have been implicated in stillbirth
and club foot deformities.
In certain
regions, manganese is added to gasoline as an anti-knock agent.
Organic Solvents
Because they evaporate in the air at room temperature, organic
solvents can penetrate the skin and are easily inhaled. In fact,
studies have found that taking a 10-minute shower in contaminated
water exposes a person to more solvents than drinking two quarts of
the same water.
Organic
solvents also can cross the placenta, sometimes accumulating in high
concentrations in the fetus. Solvents have been shown to increase
the risk of spontaneous abortion as well as certain birth defects
and childhood cancers.
Organic solvents are found in many settings, including electronic
factories, dry cleaning and auto repair places, labs and paint
shops. Solvents come out of cars' tail pipes in the form of gasoline
exhaust and they remain on clothing in dry-cleaning bags.
Pesticides
Toxic
by design, pesticides are intended to kill insects, weeds and
fungus. Unfortunately, that means most are toxic to human nervous
systems as well. Pesticides have been linked to cancer and
reproductive, developmental, neurological and immune-system damage,
depending on exposure levels.
The diets of infants and children are likely to contain pesticide
residues. A 1994 government study found pesticide residues on 2
percent of vegetables and 1.5 percent of grains as well as in dairy
products, eggs, fish and fruits.
Sources: Residues can be found in food, water, homes and on pets.
Pesticides are most often used for outdoor lawn and garden care, but
indoor air and dust also tend to have high concentrations.
Endocrine Disruptors
Chemicals that interfere with the normal function of
hormones in men, women and developing infants, endocrine disruptors
include chemicals that act as estrogens, anti-estrogens, androgens
such as testosterone and anti-androgens. Endocrine systems generally
control body growth, organ development, metabolism and regular body
processes such as kidney function, body temperature and calcium
regulation; therefore endocrine disruptors also include chemicals
that interfere with hormones such as thyroid, cortisol, insulin or
growth regulators. Scientists are attempting to compile a list of
such chemicals -- and it keeps growing. These chemicals are being
tested for potential links to prostate, testicular and breast
cancers, as well as lowered sperm counts and behavioral and learning
abnormalities.
The pesticide DDT, described in Rachel Carson’s 1962 book, "Silent
Spring," is now recognized by many scientists as a potent estrogenic
chemical. Other synthetic chemicals that act as endocrine disruptors
and to which humans are widely exposed include dioxin, a byproduct
of various industrial process, primarily waste incineration;
polychlorinated biphenyls (PCBs), now banned but still persistent in
the environment and in the food chain; and phthalates, perhaps the
most abundant man-made chemicals of all.
About one billion pounds of 25 different phthalate compounds are
produced each year, and they tend to accumulate in fat tissue and
are easily absorbed through the skin. Major sources: plastic wrap,
soft plastics, including soft plastic toys, plastic medical
equipment and some household products.
Source: Generations at Risk |
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Microsoft Corporation. All rights reserved. |
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