journalist-as-guinea-pig experiment is taking a disturbing turn. A Swedish
chemist is on the phone, talking about flame retardants, chemicals added for
safety to just about any product that can burn. Found in mattresses, carpets,
the plastic casing of televisions, electronic circuit boards, and
automobiles, flame retardants save hundreds of lives a year in the United States
alone. These, however, are where they should not be: inside my body.
Ĺke Bergman of Stockholm
University tells me he
has received the results of a chemical analysis of my blood, which measured
levels of flame-retarding compounds called polybrominated
diphenyl ethers. In mice and rats, high doses of
PBDEs interfere with thyroid function, cause reproductive and neurological
problems, and hamper neurological development. Little is known about their
impact on human health.
"I hope you are not nervous, but this
concentration is very high," Bergman says with a light Swedish accent.
My blood level of one particularly toxic PBDE, found primarily in U.S.-made
products, is 10 times the average found in a small study of U.S. residents and more than 200 times the
average in Sweden.
The news about another PBDE variant—also toxic to animals—is nearly as bad.
My levels would be high even if I were a worker in a factory making the
stuff, Bergman says.
In fact I'm a writer engaged in a journey of
chemical self-discovery. Last fall I had myself tested for 320 chemicals I
might have picked up from food, drink, the air I breathe, and the products
that touch my skin—my own secret stash of compounds acquired by merely
living. It includes older chemicals that I might have been exposed to decades
ago, such as DDT and PCBs; pollutants like lead, mercury, and dioxins; newer
pesticides and plastic ingredients; and the near-miraculous compounds that
lurk just beneath the surface of modern life, making shampoos fragrant, pans
nonstick, and fabrics water-resistant and fire-safe.
The tests are too expensive for most individuals—National
Geographic paid for mine, which would normally cost around $15,000—and
only a few labs have the technical expertise to detect the trace amounts
involved. I ran the tests to learn what substances build up in a typical
American over a lifetime, and where they might come from. I was also
searching for a way to think about risks, benefits, and uncertainty—the
complex trade-offs embodied in the chemical "body burden" that
swirls around inside all of us.
Now I'm learning more than I really want to know.
Bergman wants to get to the bottom of my
flame-retardant mystery. Have I recently bought new furniture or rugs? No. Do
I spend a lot of time around computer monitors? No, I use a titanium laptop.
Do I live near a factory making flame retardants? Nope, the closest one is over
a thousand miles (1,600 kilometers) away. Then I come up with an idea.
"What about airplanes?" I ask.
"Yah," he says, "do you fly a
"I flew almost 200,000 miles (300,000
kilometers) last year," I say. In fact, as I spoke to Bergman, I was sitting
in an airport waiting for a flight from my hometown of San
Francisco to London.
"Interesting," Bergman says, telling me
that he has long been curious about PBDE exposure inside airplanes, whose
plastic and fabric interiors are drenched in flame retardants to meet safety
standards set by the Federal Aviation Administration and its counterparts
overseas. "I have been wanting to apply for a grant to test pilots and
flight attendants for PBDEs," Bergman says as I hear my flight announced
overhead. But for now the airplane connection is only a hypothesis. Where I
picked up this chemical that I had not even heard of until a few weeks ago
remains a mystery. And there's the bigger question: How worried should I be?
The same can be asked of other chemicals I've
absorbed from air, water, the nonstick pan I used to scramble my eggs this
morning, my faintly scented shampoo, the sleek curve of my cell phone. I'm
healthy, and as far as I know have no symptoms associated with chemical
exposure. In large doses, some of these substances, from mercury to PCBs and
dioxins, the notorious contaminants in Agent Orange, have horrific effects.
But many toxicologists—and not just those who have ties to the chemical
industry—insist that the minuscule smidgens of chemicals inside us are mostly
nothing to worry about.
"In toxicology, dose is everything,"
says Karl Rozman, a toxicologist at the University
of Kansas Medical Center, "and these doses are too low to be
dangerous." One part per billion (ppb), a standard unit for measuring
most chemicals inside us, is like putting half a teaspoon (two milliliters)
of red dye into an Olympic-size swimming pool. What's more, some of the most
feared substances, such as mercury, dissipate within days or weeks—or would
if we weren't constantly re-exposed.
Yet even though many health statistics have been
improving over the past few decades, a few illnesses are rising mysteriously.
From the early 1980s through the late 1990s, autism increased tenfold; from
the early 1970s through the mid-1990s, one type of leukemia was up 62
percent, male birth defects doubled, and childhood brain cancer was up 40
percent. Some experts suspect a link to the man-made chemicals that pervade
our food, water, and air. There's little firm evidence. But over the years,
one chemical after another that was thought to be harmless turned out
otherwise once the facts were in.
The classic example is lead. In 1971 the U.S.
Surgeon General declared that lead levels of 40 micrograms per deciliter of
blood were safe. It's now known that any detectable lead can cause
neurological damage in children, shaving off IQ points. From DDT to PCBs, the
chemical industry has released compounds first and discovered damaging health
effects later. Regulators have often allowed a standard of innocent until
proven guilty in what Leo Trasande, a pediatrician
and environmental health specialist at Mount Sinai
Hospital in New
York City, calls "an uncontrolled experiment on America's
Each year the U.S. Environmental Protection Agency
(EPA) reviews an average of 1,700 new compounds that industry is seeking
to introduce. Yet the 1976 Toxic Substances Control Act requires that they be
tested for any ill effects before approval only if evidence of potential harm
exists—which is seldom the case for new chemicals. The agency approves about
90 percent of the new compounds without restrictions. Only a quarter of the
82,000 chemicals in use in the U.S. have ever been tested for
Studies by the Environmental Working Group, an
environmental advocacy organization that helped pioneer the concept of a
"body burden" of toxic chemicals, had found hundreds of chemical
traces in the bodies of volunteers. But until recently, no one had even
measured average levels of exposure among large numbers of Americans. No
regulations required it, the tests are expensive, and technology sensitive
enough to measure the tiniest levels didn't exist.
Last year the Centers for Disease Control and
Prevention (CDC) took a step toward closing that gap when it released
data on 148 substances, from DDT and other pesticides to metals, PCBs, and
plastic ingredients, measured in the blood and urine of several thousand
people. The study said little about health impacts on the people tested or
how they might have encountered the chemicals. "The good news is that we
are getting real data about exposure levels," says James Pirkle, the study's lead author. "This gives us a
place to start."
I began my own chemical journey on an October
morning at the Mount Sinai Hospital in New
York City, where I gave urine and had blood drawn
under the supervision of Leo Trasande. Trasande specializes in childhood exposures to mercury
and other brain toxins. He had agreed to be one of several expert advisers on
this project, which began as a Sinai phlebotomist extracted 14 vials of
blood—so much that at vial 12 I felt woozy and went into a cold sweat. At
vial 13 Trasande grabbed smelling salts, which hit
my nostrils like a whiff of fire and allowed me to finish.
From New York my
samples were shipped to Axys Analytical Services on
Vancouver Island in Canada,
one of a handful of state-of-the-art labs specializing in subtle chemical
detection, analyzing everything from eagle eggs to human tissue for
researchers and government agencies. A few weeks later, I followed my samples
to see how Axys teased out the tiny loads of
compounds inside me.
I watched the specimens go through multiple stages
of processing, which slowly separated sets of target chemicals from the
thousands of other compounds, natural and unnatural, in my blood and urine.
The extracts then went into a high-tech clean room containing mass
spectrometers, sleek, freezer-size devices that work by flinging the
components of a sample through a vacuum, down a long tube. Along the way, a
magnetic field deflects the molecules, with lighter molecules swerving the
most. The exact amount of deflection indicates each molecule's size and
A few weeks later, Axys
sent me my results—a grid of numbers in parts per billion or trillion—and I
set out to learn, as best I could, where those toxic traces came from.
Some of them date back to my time in the womb,
when my mother downloaded part of her own chemical burden through the
placenta and the umbilical cord. More came after I was born, in her breast
Once weaned, I began collecting my own chemicals
as I grew up in northeastern Kansas, a few
miles outside Kansas City.
There I spent countless hot, muggy summer days playing in a dump near the Kansas River. Situated on a high limestone bluff above
the fast brown water lined by cottonwoods and railroad tracks, the dump was a
mother lode of old bottles, broken machines, steering wheels, and other items
only boys can fully appreciate.
This was the late 1960s, and my friends and I had
no way of knowing that this dump would later be declared an EPA superfund
site, on the National Priority List for hazardous places. It turned out that
for years, companies and individuals in this corner of Johnson County
had dumped thousands of pounds of material contaminated with toxic chemicals
here. "It was started as a landfill before there were any rules and
regulations on how landfills were done," says Denise Jordan-Izaguirre, the regional representative for the federal
Agency for Toxic Substances and Disease Registry. "There were metal
tailings and heavy metals dumped in there. It was unfenced, unrestricted, so
kids had access to it."
Kids like me.
Now capped, sealed, and closely monitored, the
dump, called the Doepke-Holliday Site, also happens
to be half a mile upriver from a county water intake that supplied drinking
water for my family and 45,000 other households. "From what we can
gather, there were contaminants going into the river," says Shelley
Brodie, the EPA Remedial Project Manager for Doepke.
In the 1960s, the county treated water drawn from the river, but not for all
contaminants. Drinking water also came from 21 wells that tapped the aquifer
When I was a boy, my corner of Kansas was filthy, and the dump wasn't the
only source of toxins. Industry lined the river a few miles away—factories
making cars, soap, and fertilizers and other agricultural chemicals—and a
power plant belched fumes. When we drove past the plants toward downtown Kansas City, we plunged
into a noxious cloud that engulfed the car with smoke and an awful chemical
stench. Flames rose from fertilizer plant stacks, burning off mustard-yellow
plumes of sodium, and animal waste poured into the river. In the nearby
farmland, trucks and crop dusters sprayed DDT and other pesticides in great,
puffy clouds that we kids sometimes rode our bikes through, holding our
breath and feeling very brave.
Today the air is clear, and the river free of
effluents—a visible testament to the success of the U.S. environmental
cleanup, spurred by the Clean Air and Clean Water Acts of the 1970s. But my Axys test results read like a chemical diary from 40
years ago. My blood contains traces of several chemicals now banned or
restricted, including DDT (in the form of DDE, one of its breakdown products)
and other pesticides such as the termite-killers chlordane and heptachlor.
The levels are about what you would expect decades after exposure, says Rozman, the toxicologist at the University of Kansas
Medical Center. My childhood playing in the dump, drinking the water, and
breathing the polluted air could also explain some of the lead and dioxins in
my blood, he says.
I went to college at a place and time that put me
at the height of exposure for another set of substances found inside me—PCBs,
once used as electrical insulators and heat-exchange fluids in transformers
and other products. PCBs can lurk in the soil anywhere there's a dump or an
old factory. But some of the largest releases took place along New York's Hudson River from the 1940s to the 1970s,
when General Electric used PCBs at factories in the towns of Hudson Falls
and Fort Edward. About 140 miles (225
kilometers) downstream is the city of Poughkeepsie,
where I attended Vassar
College in the late
PCBs, oily liquids or solids, can persist in the
environment for decades. In animals, they impair liver function, raise blood
lipids, and cause cancers. Some of the 209 different PCBs chemically resemble
dioxins and cause other mischief in lab animals: reproductive and nervous
system damage, as well as developmental problems. By 1976, the toxicity of
PCBs was unmistakable; the United
States banned them, and GE stopped using
them. But until then, GE legally dumped excess PCBs into the Hudson,
which swept them all the way downriver to Poughkeepsie,
one of eight cities that draw their drinking water from the Hudson.
In 1984, a 200-mile (300 kilometers) stretch of
the Hudson, from Hudson
Falls to New
York City, was declared a superfund site, and plans to rid the river of PCBs were set in motion. GE has spent
300 million dollars on the cleanup so far, dredging up and disposing of PCBs
in the river sediment under the supervision of the EPA. It is also working to
stop the seepage of PCBs into the river from the factories.
Birds and other wildlife along the Hudson are thought to
have suffered from the pollution, but its impact on humans is less
definitive. One study in Hudson River
communities found a 20 percent increase in the rate of hospitalization for
respiratory diseases, while another, more reassuringly, found no increase in
cancer deaths in the contaminated region. But among many of the locals, the
fear is palpable.
"I grew up a block from the Fort Edward
plant," says Dennis Prevost, a retired Army officer and public health
advocate, who blames PCBs for the brain cancers that killed his brother at
age 46 and a neighbor in her 20s. "The PCBs have migrated under the
parking lot and into the community aquifer," which Prevost says was the
source of Fort Edward's drinking water until
municipal water replaced wells in 1984.
Ed Fitzgerald of the State University of New York
at Albany, a
former staff scientist at the state department of health, is conducting the
most thorough study yet of the health effects of PCBs in the area. He says he
has explained to Prevost and other residents that the risk from the wells was
probably small because PCBs tend to settle to the bottom of an aquifer.
Eating contaminated fish caught in the Hudson
is a more likely exposure route, he says.
I didn't eat much Hudson
River fish during my college days in the 1970s, but the drinking
water in my dorm could have contained traces of the PCBs pouring into the
river far upstream. That may be how I picked up my PCB body burden, which was
about average for an American. Or maybe not. "PCBs are everywhere,"
says Leo Rosales, a local EPA official, "so who knows where you got
Back home in San
Francisco, I encounter a newer generation of
industrial chemicals—compounds that are not banned, and, like flame
retardants, are increasing year by year in the environment and in my body.
Sipping water after a workout, I could be exposing myself to Bisphenol A, an ingredient in rigid plastics from water
bottles to safety goggles. Bisphenol A causes
reproductive system abnormalities in animals. My levels were so low they were
undetectable—a rare moment of relief in my toxic odyssey.
And that faint lavender scent as I shampoo my
hair? Credit it to phthalates, molecules that dissolve fragrances, thicken
lotions, and add flexibility to PVC, vinyl, and some intravenous tubes in
hospitals. The dashboards of most cars are loaded with phthalates, and so is
some plastic food wrap. Heat and wear can release phthalate molecules, and
humans swallow them or absorb them through the skin. Because they dissipate
after a few minutes to a few hours in the body, most people's levels
fluctuate during the day.
Like bisphenol A,
phthalates disrupt reproductive development in mice. An expert panel convened
by the National Toxicology Program recently concluded that although the
evidence so far doesn't prove that phthalates pose any risk to people, it
does raise "concern," especially about potential effects on
infants. "We don't have the data in humans to know if the current levels
are safe," says Antonia Calafat, a CDC phthalates expert. I scored
higher than the mean in five out of seven phthalates tested. One of them, monomethyl phthalate, came in at 34.8 ppb, in the top 5
percent for Americans. Leo Trasande speculates that
some of my phthalate levels were high because I gave my urine sample in the
morning, just after I had showered and washed my hair.
My inventory of household chemicals also includes perfluorinated acids (PFAs)—tough, chemically resistant
compounds that go into making nonstick and stain-resistant coatings. 3M also
used them in its Scotchgard protector products
until it found that the specific PFA compounds in Scotchgard
were escaping into the environment and phased them out. In animals these
chemicals damage the liver, affect thyroid hormones, and cause birth defects
and perhaps cancer, but not much is known about their toxicity in humans.
Long-range pollution left its mark on my results
as well: My blood contained low, probably harmless, levels of dioxins, which
escape from paper mills, certain chemical plants, and incinerators. In the
environment, dioxins settle on soil and in the water, then pass into the food
chain. They build up in animal fat, and most people pick them up from meat
and dairy products.
And then there is mercury, a neurotoxin that can
permanently impair memory, learning centers, and behavior. Coal-burning power
plants are a major source of mercury, sending it out their stacks into the
atmosphere, where it disperses in the wind, falls in rain, and eventually
washes into lakes, streams, or oceans. There bacteria transform it into a
compound called methylmercury, which moves up the food chain after plankton
absorb it from the water and are eaten by small fish. Large predatory fish at
the top of the marine food chain, like tuna and swordfish, accumulate the
highest concentrations of methylmercury—and pass it on to seafood lovers.
For people in northern California,
mercury exposure is also a legacy of the gold rush 150 years ago, when miners
used quicksilver, or liquid mercury, to separate the gold from other ores in
the hodgepodge of mines in the Sierra Nevada.
Over the decades, streams and groundwater washed mercury-laden sediment out
of the old mine tailings and swept it into San Francisco Bay.
I don't eat much fish, and the levels of mercury
in my blood were modest. But I wondered what would happen if I gorged on
large fish for a meal or two. So one afternoon I bought some halibut and
swordfish at a fish market in the old Ferry
Building on San Francisco Bay.
Both were caught in the ocean just outside the Golden
Gate, where they might have picked up mercury from the old
mines. That night I ate the halibut with basil and a dash of soy sauce; I
downed the swordfish for breakfast with eggs (cooked in my nonstick pan).
Twenty-four hours later I had my blood drawn and
retested. My level of mercury had more than doubled, from 5 micrograms per
liter to a higher-than-recommended 12. Mercury at 70 or 80 micrograms per
liter is dangerous for adults, says Leo Trasande,
and much lower levels can affect children. "Children have suffered
losses in IQ at 5.8 micrograms." He advises me to avoid repeating the
It's a lot harder to dodge the PBDE flame
retardants responsible for the most worrisome of my test results. My
world—and yours—has become saturated with them since they were introduced
about 30 years ago.
Scientists have found the compounds planetwide, in polar bears in the Arctic, cormorants in England, and
killer whales in the Pacific. Bergman, the Swedish chemist, and his
colleagues first called attention to potential health risks in 1998 when they
reported an alarming increase in PBDEs in human breast milk, from none in
milk preserved in 1972 to an average of four ppb in 1997.
The compounds escape from treated plastic and
fabrics in dust particles or as gases that cling to dust. People inhale the
dust; infants crawling on the floor get an especially high dose. Bergman
describes a family, tested in Oakland,
California, by the Oakland
Tribune, whose two small children had blood levels even higher than mine.
When he and his colleagues summed up the test results for six different
PBDEs, they found total levels of 390 ppb in the five-year-old girl and 650
ppb—twice my total—in the 18-month-old boy.
In 2001, researchers in Sweden fed young mice a PBDE
mixture similar to one used in furniture and found that they did poorly on
tests of learning, memory, and behavior. Last year, scientists at Berlin's Charité University
reported that pregnant female rats with PBDE levels no higher than mine gave
birth to male pups with impaired reproductive health.
Linda Birnbaum, an EPA expert on these flame
retardants, says that researchers will have to identify many more people with
high PBDE exposures, like the Oakland
family and me, before they will be able to detect any human effects. Bergman
says that in a pregnant woman my levels would be of concern. "Any level
above a hundred parts per billion is a risk to newborns," he guesses. No
one knows for sure.
Any margin of safety may be narrowing. In a review
of several studies, Ronald Hites of Indiana University found an exponential rise
in people and animals, with the levels doubling every three to five years.
Now the CDC is putting a comprehensive study of PBDE levels in the U.S. on a
fast track, with results due out late this year. Pirkle,
who is running the study, says my seemingly extreme levels may no longer be
out of the ordinary. "We'll let you know," he says.
Given the stakes, why take a chance on these
chemicals? Why not immediately ban them? In 2004, Europe
did just that for the penta- and octa-BDEs, which animal tests suggest are the most toxic
of the compounds. California will also ban
these forms by 2008, and in 2004 Chemtura, an Indiana company that is the only U.S. maker of
pentas and octas, agreed
to phase them out. Currently, there are no plans to ban the much more
prevalent deca-BDEs. They reportedly break down
more quickly in the environment and in people, although their breakdown
products may include the same old pentas and octas.
Nor is it clear that banning a suspect chemical is
always the best option. Flaming beds and airplane seats are not an inviting
prospect either. The University of Surrey in England recently assessed the
risks and benefits of flame retardants in consumer products. The report
concluded: "The benefits of many flame retardants in reducing the risk
from fire outweigh the risks to human health."
Except for some pollutants, after all, every
industrial chemical was created for a purpose. Even DDT, the archvillain of Rachel Carson's 1962 classic book Silent
Spring, which launched the modern environmental movement, was once hailed
as a miracle substance because it killed the mosquitoes that carry malaria,
yellow fever, and other scourges. It saved countless lives before it was
banned in much of the world because of its toxicity to wildlife.
"Chemicals are not all bad," says Scott Phillips, a medical
toxicologist in Denver.
"While we have seen some cancer rates rise," he says, "we also
have seen a doubling of the human life span in the past century."
The key is knowing more about these substances, so
we are not blindsided by unexpected hazards, says California State Senator
Deborah Ortiz, chair of the Senate Health Committee and the author of a bill
to monitor chemical exposure. "We benefit from these chemicals, but
there are consequences, and we need to understand these consequences much
better than we do now." Sarah Brozena of the
industry-supported American Chemistry Council thinks safeguards are adequate
now, but she concedes: "That's not to say this process was done right in
The European Union last year gave initial approval
to a measure called REACH—Registration, Evaluation, and Authorization of
Chemicals—which would require companies to prove the substances they market
or use are safe, or that the benefits outweigh any risks. The bill, which the
chemical industry and the U.S.
government oppose, would also encourage companies to find safer alternatives
to suspect flame retardants, pesticides, solvents, and other chemicals. That
would give a boost to the so-called green chemistry movement, a search for
alternatives that is already under way in laboratories on both sides of the Atlantic.
As unsettling as my journey down chemical lane
was, it left out thousands of compounds, among them pesticides, plastics,
solvents, and a rocket-fuel ingredient called perchlorate that is polluting
groundwater in many regions of the country. Nor was I tested for chemical
cocktails—mixtures of chemicals that may do little harm on their own but act
together to damage human cells. Mixed together, pesticides, PCBs, phthalates,
and others "might have additive effects, or they might be
antagonistic," says James Pirkle of the CDC,
"or they may do nothing. We don't know."
Soon after I receive my results, I show them to my
internist, who admits that he too knows little about these chemicals, other
than lead and mercury. But he confirms that I am healthy, as far as he can
tell. He tells me not to worry. So I'll keep flying, and scrambling my eggs
on Teflon, and using that scented shampoo. But I'll never feel quite the same
about the chemicals that make life better in so many ways.