CDC results are in: We're full of contaminants
Study offers tool to assess threat of synthetic chemicals
By Douglas Fischer, STAFF WRITER

The U.S. Centers for Disease Control and Prevention released its third
assessment of the
nation's chemical body burden Thursday, and as expected it shows we're all
contaminated
with a stew of pesticides, solvents, plastics and metals that we pick up daily
from our
material world.
The release, called a "watershed event" by various public health officials and
scientists,
offers regulators and researchers alike a powerful tool to assess the threat
posed by
environmental contaminants and to guide public health decisions in the future.

"If you compare this to space exploration, we're now putting together the Hubble
telescope," said Thomas Burke, chairman of the National Academy of Science's
Committee
on Human Biomonitoring for Environmental Toxicants.

"We're on the threshold of great progress."

The assessment, the CDC's Third National Report on Human Exposure to
Environmental
Chemicals, details the U.S. population's exposure to 148 different compounds
that are
either found in consumer goods and manufacturing byproducts or have been banned
from
the market.

The findings offer both good and bad news:

-Children in many instances have higher concentrations of pollutants than
adults, a
finding particularly true for many heavy metals, pesticides and a family of
chemicals called
"phthalates" used to increase plastic's flexibility and resiliency.

-The most common insect-killer used in homes today — a third-generation family
of
insecticides known as "pyrethroids" and touted for its ability to rapidly
decompose —
contaminates virtually all of us.

-Traces of secondhand tobacco smoke in nonsmokers have dropped almost 70 percent
since the late 1980s, suggesting public health laws against smoking are paying
rich
dividends. Still, levels in children remain twice as high as adults, and
nonsmoking African
Americans — for reasons unknown — have concentrations twice as high as white or
Latino
nonsmokers.

-Exposure to mercury, a potent developmental neurotoxin, continues to be a
concern for
women of childbearing age. Two years ago, the CDC reported roughly 8 percent of
such
women had levels approaching what the U.S. Environmental Protection Agency
considered
harmful to the fetus. This year's report finds almost 6 percent near that
threshold.

"Whether it's 6 percent or 8 percent, that's not real progress," Burke said.
"What's
important is that there's still a vulnerable higher tier of the population
that's exposed."

-Lead continues to be the poster child for what happens when regulators attempt
to rid a
hazardous compound from commerce. Ten years ago, nearly 1 in 25 children had
elevated
blood lead levels. By 2002, just 1 in 60 did.

The report offered almost no sense of what this chemical "body burden" means for
our
health. Health officials said Thursday they need to know what is in us before
they can
begin to understand its effect.

"This is a giant step forward to understanding the relationship between exposure




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to chemicals and their potential health effects," said Dr. Julie Gerberding,
CDC's director.
"Knowing levels present in the population has a very important use in defining
research.
"It's our responsibility to take this to the next step," she added, and "assess
what, if any,
health effects are associated with this."

Still, for all their impact, the CDC's findings barely scratch the surface of
what's known
about environmental exposure to synthetic chemicals.

Nearly 80,000 chemicals are registered for use in commerce today, with 3,000
used in
large volumes. The CDC looked at 148 — a step up from the 27 examined in the
first
report, released in 1999.

"We're only looking at 43 (pesticides), and there are more than 1,200," said
Margaret
Reeves, senior scientist with the San Francisco-based Pesticide Action Network.
"We're
looking at the tip of the iceberg."

Industry groups cautioned Thursday that few conclusions can be drawn between
exposure
at current levels and potential harm.

"Public health officials and manufacturers need to go back and make sure those
low levels
of exposure are safe, as was previously assumed," said Chris VandenHuevel,
spokesman
for the American Chemistry Council, representing every major chemical
manufacturer in
the United States.

To do that, the nation needs more biomonitoring, say many health experts. The
CDC is the
sole source for such information. Efforts to create a similar program in
California have
drawn consistent opposition from industry.

With better information would come better public health decisions, said Dr.
Jerome
Paulson, associate professor of pediatrics and public health at George
Washington
University in Washington, D.C.

"Without this kind of information, we don't know where we are, we don't know
what risks
we're exposed to, we don't know if those risks are significant and whether we
have to
intervene."

But what's obvious, he and others added Thursday, is that these compounds are
everywhere.

"It's not clear that having these things in (our) bodies is necessarily bad for
you," Paulson
said.

"It is very clear that as a global society we have not been careful and that we
have really
fouled our nest."


The Oakland Tribune's investigation of our chemical "body burden" can be found
online at
http://www.insidebayarea.com/bodyburden.