National Geographic: October 2006: The Pollution Within

[Guest guest]

By Ewing Duncan

Photographs by Essick

Modern chemistry keeps insects from ravaging crops, lifts stains from

carpets, and saves lives. But the ubiquity of chemicals is taking a toll. Many

of

the compounds absorbed by the body stay there for years—and fears about their

health effects are growing.

My 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.

Ã…ke 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 lot? "

" 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 children. "

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 toxicity.

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 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 Canada 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 identity.

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 milk.

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 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 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

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 near Doepke.

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 . About 140 miles (225 kilometers) downstream is

the

city of Poughkeepsie, where I attended Vassar College in the late 1970s.

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 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 '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 les, a local EPA official, " so who knows where you

got it. "

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

gorge experiment.

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

Medical

School reported that pregnant female rats with PBDE levels no higher than

mine gave birth to male pups with impaired reproductive health.

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,

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 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 , 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. " 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 past. "

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 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.

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