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Chemical contamination of water, air and food supplies has been documented for decades, but only recently have scientists begun to uncover details about the industrial pollution of a much more intimate site: our bodies.
It should come as no surprise that industrial chemicals are running through our veins. Industry reported dumping 7.1 billion pounds of hazardous compounds into the air and water in the United States in the year 2000, according to the most recent Toxic Release Inventory, a U.S. Environmental Protection Agency (EPA) program that tracks only a subset of industries.
But not until recently, with advances in the technology of biomonitoring, have scientists been able to accurately measure the actual levels of chemicals in people's bodies.
Now, with the recent release of the largest-ever biomonitoring study by the U.S. Centers for Disease Control and Prevention (CDC), and a new peer-reviewed study by independent researchers, scientists know more than they ever have about a new evolutionary phenomenon: the universal chemical body burden of people.
"This is irrefutable proof that humans carry around scores of industrial chemicals, most of which have never been tested for human health effects," says Jane Houlihan, vice president of research at the Washington D.C.-based Environmental Working Group (EWG), and lead author of one of the studies.
Most of these chemicals did not exist in the environment, let alone human bodies, just 75 years ago.
The $450-billion chemical industry has responded to the revelations with assurances that the mere presence of chemicals in humans is no proof of harm, but critics say the real story is that the general population is the test subject of a giant chemical experiment.
Chemical load
The new CDC National Report on Human Exposure to Environmental Chemicals, released at the end of January, is the largest set of body burden data ever collected in the United States and the first time chemical exposure by age, race and sex has been analyzed on a national scale. CDC tested the blood and urine of a nationally representative group of about 2,500 anonymous people for the presence of 116 chemicals, most of which are toxic in laboratory animals.
"This report is by far the most extensive assessment ever made of the exposure in the U.S. population to environmental chemicals," says CDC Deputy Director Dr. David Fleming. "It's a quantum leap forward in providing objective scientific information about what's getting into people's bodies and how much."
All of the 116 chemicals were found in people. But public health experts say one of the most disturbing findings in this round of data is that children had higher body burdens than adults of some of the most toxic chemicals, including lead, tobacco smoke and organophosphate pesticides.
"This is a concern because of the potential of toxic chemicals to interfere with development," and because children's systems may be more sensitive to toxic impacts, says Dr. Lynn Goldman, a former EPA official and a professor at the Johns Hopkins University School of Public Health.
Children had double the level of adults of the pesticide chlorpyrifos (known as Dursban) � a chemical that animal studies indicate has long-term effects on brain development if exposure occurs early in life. Dursban was the most widely used insecticide in the United States until the EPA banned its use in households a year ago, although some uses remain legal. Other organophosphate pesticides, which are also linked to neurological and nervous system damage in animal studies, remain in widespread use.
Children were also disproportionately exposed to some of the most toxic phthalates, the CDC found. Phthalates � a class of industrial chemicals used in polyvinyl chloride (PVC) plastic, cosmetics and other consumer products � cause a spectrum of health effects in animal studies, including damage to the liver, kidneys, lungs and the reproductive system, particularly the testes of developing males.
The phthalates found at the highest levels in children are "the most toxic and the ones present in plastics used in consumer products at home," Goldman says.
The phthalates most widely used in beauty products were found at the highest levels in adolescents and adult women, suggesting that consumer products are a likely source of phthalate exposure. Looking more closely into sources of phthalate exposure is high on the priority list for future CDC studies, says James Pirkle, assistant director of science at the CDC's National Center for Environmental Health.
CDC also identified some spikes among ethnic populations. The insecticide DDT, banned in the 1970s in the United States, was found in Mexican Americans at triple the levels present in the general population. The higher exposures could perhaps be due to recent use of the pesticide in Mexico, or because of exposure to DDT that still remains in the soil on farms where many Mexican Americans work.
CDC found mercury at the highest levels in African-American women of childbearing age, and the study confirmed that 5 to 10 percent of all U.S. women of childbearing age already have enough mercury in their bodies to pose a risk of neurological damage to their developing babies. CDC scientists say that future agency studies will include better breakdowns of the types of mercury found in people in an effort to pinpoint whether the exposure is coming from contaminated fish or other sources, and why black women exhibit the highest levels of contamination.
CDC plans to release more body burden data every two years, and scientists say it will take months to digest the reams of information in the current report. But they agree that it is a major and unprecedented step toward understanding the health effects of chemicals.
"It's the first time ever we've had a clear picture of the chemicals in people's bodies in the United States," Goldman says. "This allows us to begin to connect the dots between chemical exposure and disease."
Responsible Parties
If the CDC report provides a panoramic view of the body burden of the U.S. population, another new study offers a close-up snapshot at what individuals are carrying around in their bodies.
Released a day before the CDC report was another first-of-its-kind biomonitoring study, conducted by the Environmental Working Group in partnership with Mt. Sinai School of Community Medicine in New York City and Commonweal, a Bolinas, California non-profit that works with families with cancer. EWG looked for 210 chemicals in nine people and created a personal body burden profile for each � putting a human face, as well as a corporate face, on the problem.
Using peer-reviewed studies and various government health assessments, the report links the chemicals to potential health effects and found that, on average, each person's body had 50 or more chemicals that are linked to cancer in humans or lab animals, considered toxic to the brain and nervous system, associated with birth defects or abnormal development, or known to interfere with the hormone system.
The report also connected the chemicals to 11,700 consumer products, and those products to 164 past and current manufacturers.
The study showed, for example, that Andrea Martin, 56, of Sausalito, California, contained at least 95 toxic chemicals in her body at the time of the test, which she likely ingested from scores of consumer products that are manufactured by Shell, Union Carbide, Exxon, Dow and Monsanto, among others.
"I was shocked at the breadth and variety of the number of chemicals. I was outraged to find out that without my permission, without my knowledge, my body was accumulating this toxic mixture," Martin says.
Martin appeared in a full-page ad announcing the body burden report that ran in the New York Times in January. Her photo was stamped with the headline: "Warning: Andrea Martin contains 59 cancer causing industrial chemicals."
Martin also happens to have cancer. At 42, she was diagnosed with an advanced case of breast cancer, underwent aggressive treatment and later contracted cancer in the other breast. A year ago, she was diagnosed with a large malignant brain tumor.
"My body biology is susceptible to cancer," Martin surmises. She has been asked if she thinks her chemical body burden caused the disease. "No one can say for sure, but no one can say it hasn't either," she says. "We deserve to know what toxins are in our bodies. We have a right to know what health effects these chemicals have."
The unknown and the Chemophiles
Unfortunately, for everything scientists now know about which chemicals are in the environment and in people, there is so much more they don't know about the effects on human health.
"Just because a chemical can be measured doesn't mean it causes disease," says Dr. Richard Jackson, director of the CDC's National Center for Environmental Health. The new CDC data offers "no new health effects information, no new understanding of the health effects from chemicals," Jackson says. "But it moves the science forward to increase this understanding."
The majority of people in the United States mistakenly believe that the government tests chemicals used in consumer products to make sure they are safe, according to an opinion poll recently conducted by the Washington Toxics Coalition.
The chemical industry also makes public claims to that effect. "Chemicals are evaluated by government scientists before being used, and there are precautions in place to help keep us safe from both natural toxins and modern chemicals," said a statement of the American Chemistry Council (ACC), the trade group for the biggest chemical manufacturers, issued in response to the CDC study.
However, most of the 75,000-plus chemicals in use today have never been evaluated for health effects. Except for pesticides, which are subject to more rigorous testing requirements, industrial chemicals are regulated by the minimal health and safety standards of the Toxic Substances Control Act (TSCA). TSCA assumes chemicals are safe until they are proven hazardous; the statute does not require chemical companies to conduct health or safety studies prior to putting a chemical on the market, or to monitor chemicals once they are in use.
EWG accuses the chemical industry of creating the lax regulatory situation. "Chemical companies are pressuring our elected leaders to restrict new research and block common sense safeguards," says the New York Times ad paid for by the environmental group.
The ACC blasted the ad as an attempt to "put bogus words in the mouths of the men and women who make essential and life-saving products that we rely on every day."
"Contrary to the allegations in the advertisement, chemical makers support additional government research and also are spending millions of dollars every year in collaboration with government scientists on research into the relationship between chemicals and health," said the ACC in a statement.
Industry also points to its voluntary efforts to improve health and safety performance. The Responsible Care program, a voluntary environmental improvement program established by the ACC in 1988 in response to criticism of industry's environmental record, "has resulted in significant reductions in [chemical] releases to air, land and water, major improvements in workplace and community safety, and expanded programs to research and test chemicals for potential health and environmental impacts," says the ACC website.
A recent study by Duke University associate professor Michael Lenox, however, found that some members of Responsible Care are releasing more toxic substances into the environment than non-members, prompting Lenox to criticize the voluntary program as a failure.
In responding to the CDC report, industry has focused on the small levels of chemicals detected by biomonitoring. "It is remarkable that modern chemistry allows CDC scientists to measure incredibly small amounts of certain nutrients, natural food chemicals and modern chemicals in our bodies," says the ACC.
Elizabeth Whelan, president of the industry-funded American Council on Science and Health, counsels that people "should remember the basic tenet of toxicology � the dose makes the poison" � a phrase used often by industry to make the point that small doses are not harmful.
The EWG report points out that science has evolved considerably since that phrase was coined in the sixteenth century. "Toxic effects don't require high doses," says EWG's Houlihan. For instance, low doses of lead or mercury at specific days of fetal development or infancy have been shown to cause permanent health problems.
Much of the evidence of the toxicity associated with the chemicals detected by the body burden reports comes from animal studies. Many of the same health effects turning up in the animal studies are also on the rise in the human population.
The probability that a U.S. resident will develop some type of cancer at some point in his or her lifetime is now 1 in 2 for men, and 1 in 3 for women, according to the American Cancer Society. Many forms of cancer are on the rise in humans, including breast, prostate and testicular cancers, according to the National Cancer Institute.
Reproductive system defects and major nervous system disorders are also increasing in humans. Hypospadias, a birth defect of the penis, doubled in the United States between 1970 and 1993 and is now estimated to affect one of every 125 male babies born. Reported cases of autism are now almost 10 times higher than in the mid-1980s, according to some recent studies.
For all those diseases, "there is either data that demonstrates or data that suggests that environmental factors may be contributing to the increase, and chemical exposures may be part of that picture," says Michael Lerner, one of the EWG test subjects and the founder of Commonweal.
"There is an epidemic of breast cancer and there is an epidemic of many chronic diseases in this country and the question is, what is the contribution of this body burden that we are all bearing?"
Industry counters the health worries with accusations that "chemophobics" are using the CDC study to further a political agenda.
Steven Milloy, frequent defender of the chemical industry and columnist for FoxNews.com, accused environmentalists of "scheming to use the CDC report as an opportunity to launch the mother of all scare campaigns" in his column.
"The greens are set to terrorize us with yet another junk science-fueled campaign intended to advance their mindless anti-chemical agenda," Milloy wrote.
"There has been an awful lot of attention given to this in the activist community to create some fear in the minds of the public," says Jay Vroom, president of CropLife America, a trade group for the pesticide industry.
"We don't believe there's any new evidence to suggest there is cause for concern," Vroom says of the CDC report. "The pesticide data contained in the report indicates that the American public can be assured that the regulatory safeguards for pesticides that are in place are very tough and are working as they are intended. Americans can be confident about the safety of our food supply and the public health protections made possible by pesticides."
Critics question the assumption that industry has the right to contaminate humans with products that may be harmful, and wonder why the chemical industry isn't held accountable for trespass.
"If somebody comes onto my land, it's trespassing, but companies can put 85 toxic substances into my body without my permission and tell me there is nothing I can do about it. That can't be right," says Charlotte Brody, RN, 54, director of the Washington, D.C.-based environmental group Health Care Without Harm and one of the nine subjects tested for the EWG report.
"outright banning works"
Two encouraging findings in the CDC report point toward at least one possible solution to the toxic body burden in humans. The levels of cotinine (a marker for tobacco smoke) decreased in children by 58 percent, while exposure to unsafe levels of lead declined among children under age 5 from 4.4 percent to 2.2 percent � although there is debate over whether any level of lead is really safe.
The CDC also reported decreasing levels in the general population of DDT and PCBs, two substances banned in the 1970s.
"It appears that regulation, and in fact outright elimination or banning, works," says Dr. Peter Orris, director of the Occupational Health Services Institute at the University of Illinois. "These are all examples of regulatory action on the part of the government which we not only can applaud, but we now have data indicating that this works and is an effective means of social policy."
Orris says the CDC data should help set priorities for public health action.
"We need to move ahead, rapidly ahead, with mercury and other regulations," he says, including ratification of the Stockholm Treaty on Persistent Organic Pollutants (POPS). "These problems are global and not local." The United States has yet to ratify the POPS Treaty, an international agreement to ban 12 of the most harmful pollutants based on their known human health effects.
EWG recommends full reform of TSCA, which the environmental group says is "so fundamentally broken that the statute needs to be rewritten." The group suggests new requirements that the chemical industry make public all internal studies about the environmental fate, human contamination and health effects of chemicals, and thoroughly test all chemicals found in humans "for their health effects in low-dose, womb-to-tomb, multi-generational studies" focused on known target organs.
The CDC will, at least, continue to provide scientists and activists with more information about the extent of human contamination for years to come. The agency's $6.5-million biomonitoring study is "budgeted to continue at the same rate every two years into the indefinite future," says the agency's Pirkle.
The CDC plans to add new chemicals, and solicit input from other government agencies, environmental groups and industry about how to make the data more useful.
In the meantime, many activists say there is enough information available now to warrant regulations to protect people, particularly children, from industrial chemicals.
"We need to change the way of manufacturing products, shifting from protection that industry gets to protection of the consumer," says test subject Martin. She advocates for a "better safe than sorry" approach that requires manufacturers to test for safety before they are allowed to introduce chemicals into commerce.
"The fact that we are walking toxic dumps is literally the result of
decisions made long ago and is not an inevitability of modern life," she
says. "If there is intelligence to come up with new chemicals and come
up with modern conveniences, the same intelligence exists to make it safe."
Stacy Malkan is the communications director of
Health Care Without Harm, an international coalition working to reduce
the environmental impact of the health care industry.
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