Kids at Risk

Kids at Risk

Chemicals in the environment come under scrutiny as the number of childhood learning problems soars

By Sheila Kaplan and Jim Morris

For more than 40 years, the family shared the big house and two trailers a mile from the Monsanto chemical plant, on the west side of Anniston, Ala. In time, the 18 of them learned to put up with the rotten-cabbage odor that wafted through town. The plant, after all, is what stood between many residents and poverty. Besides, there were family troubles: Jeanette Champion, 44, is nearly blind and has what she calls a "thinking problem." Her 45-year-old brother, David Russell, can't read or write. Her 18-year-old daughter, Misty Pate, has suffered seizures and bouts of rage. Misty's 15-year-old cousin, Shane Russell, reads at a second-grade level.

The Monsanto plant has made industrial and pharmaceutical chemicals since the 1930s. But for decades it also saturated west Anniston with polychlorinated biphenyls. PCBs have long been linked to cancer. More recently, however, researchers have discovered evidence tying the compounds to lack of coordination, diminished IQ, and poor memory among children. So when the extent of the PCB contamination in Anniston finally became clear a few years ago, a hazy picture came into focus. Perhaps the multigenerational problems of some families were not the result of poverty or bad genes. Perhaps they were caused by the chemicals in the ground.

More than 20 years ago, when Champion was still threading looms in the cotton mill, toxicologist Deborah Rice was conducting studies on young monkeys for Health Canada. The studies strongly suggested that substances like PCBs and mercury didn't just cause cancer or birth defects–the only problems for which they were tested in the United States. They also suggested that even at extremely low levels, these substances could affect the developing human brain. When given doses comparable to what a child would receive, the monkeys became impulsive and distracted and couldn't learn.

Many scientists were slow to see the significance of such research. Why worry about the loss of a few IQ points, they argued, when the real threat of chemical exposure was life-threatening disease? Today, however, a dramatic increase in learning disabilities has forced Environmental Protection Agency officials to acknowledge that they have ignored a much broader problem. One of every six children in America suffers from problems such as autism, aggression, dyslexia, and attention deficit hyperactivity disorder. In California, reported cases of autism rose 210 percent, from 3,864 to 11,995, between 1987 and 1998. In New York, the number of children with learning disabilities jumped 55 percent, from 132,000 to 204,000, between 1983 and 1996. It was in the midst of reports like these that the EPA last week essentially banned the popular pesticide Dursban as an unacceptable risk to children.

Experts have advanced a variety of theories for the increase in disorders, including better diagnostic methods. But a growing body of evidence suggests that compounds called neurotoxicants may be contributing significantly to the problem. Neurotoxicants are found in substances as common as tuna, lawn sprays, vaccines, and head-lice shampoo. Fetuses and infants exposed to these chemicals during critical windows of development, researchers now believe, may be at far higher risk for childhood learning problems than once thought. A new study from the National Academy of Sciences suggests that a combination of neurotoxicants and genes may account for nearly 25 percent of developmental problems. Chemicals alone may account for only 3 percent of cases, the study shows, but they can trigger many more. "Think of the genes as the country road," says John Harris of the California Birth Defects Monitoring Program. "And the neurotoxicants as driving 90 miles per hour in the rain."

The lead factor. Although inconclusive, the studies on neurotoxicants are intriguing. Researchers at the State University of New York-Oswego, in a federally funded study, showed that babies who had significant amounts of PCBs in their umbilical cords performed more poorly than unexposed babies in tests assessing visual recognition of faces, ability to shut out distractions, and overall intelligence. Herbert Needleman, of the University of Pittsburgh, examined 216 youths convicted in the juvenile court of Allegheny County, Pa., and 201 nondelinquent youths. In a study released last month, Needleman found that the delinquents had significantly higher bone-lead levels. In March, Frederica Perera, of Columbia University's Joseph L. Mailman School of Public Health, reported that air-sampling "backpacks" worn by 72 pregnant women in New York City picked up high concentrations of three neurotoxic pesticides that could cause disorders in their fetuses.

Chemical manufacturers–as well as some researchers and regulators–are not convinced by such findings. "There is no reason to believe we have an epidemic [of chemical-related illness] on our hands," says Robert MacPhail, chief of the EPA's Neurobehavioral Toxicology Branch. "There are still a jillion tests that have to be carried out." Robert Kaley, director of environmental affairs for Solutia, a 1997 spinoff of Monsanto's chemical operations, says that "everybody's jumping to conclusions. These kinds of links are premature at best and speculative at worst.

But the new findings, coming on the heels of more than two dozen earlier studies, have prompted the U.S. Department of Health and Human Services to dig deeper into the issue. The agency is expected to ask Congress for $1 billion to track up to 100,000 children from the womb through high school to assess the effects of chemical exposure on childhood development. U.S. Surgeon General David Satcher, who grew up in Anniston, finds the existing evidence compelling enough. "How long do you wait," he asks, "before you take the necessary action to protect children?"

The answer, in the case of the EPA, appears to be a long time. More than a dozen high-ranking current and former EPA officials say the agency has failed to exert its authority to obtain data on chemical exposure from manufacturers and to restrict the use of neurotoxicants that may be harmful to kids. The EPA's enforcement record with the chemical industry is hardly an activist one. Between 1989 and 1998, it managed to get neurotoxicity data on only nine pesticides and three industrial chemicals.

The chemical industry, meanwhile, has effectively rebuffed the few efforts the EPA has made to address the issue. In 1998, the agency tried to force makers of some of the most common chemicals to test their products for hazards to children. But the EPA backed down under election-year pressure from both political parties and decided on a voluntary system. The agency and industry are still arguing about what tests will be required. Chemical companies are among the best-connected businesses in Washington. Since January 1999, chemical manufacturers have given nearly $4.2 million to presidential candidates, congressional campaigns, and national political parties. The revolving door is nothing new in the nation's capital, but it seems to spin to particularly good effect for the Chemical Manufacturers Association. This year, the CMA retained a former top White House environmental aide who helped Al Gore develop a plan to address what the vice president called "the special impact industrial chemicals may have on children." Today, the aide, Beth Viola, is working to make the plan more industry friendly, thus contributing to delays.

Potentially hazardous chemicals should be judged "guilty until proven innocent," says EPA adviser and Yale University Prof. John Wargo. But the EPA doesn't work that way. The agency requires chemical manufacturers to prove that their products do not cause cancer or birth defects, but it does not require them to provide data on neurological effects–even though the technology for such testing now exists. The EPA is caught in a bind: It can't require a company to submit data without proof that a product is harmful. But it can't prove harm without the data. "We're in the dark," says Ward Penberthy, an EPA deputy director.

Children are particularly vulnerable to toxic chemicals. Normal brain development begins in the uterus and continues through adolescence. It requires a series of complex processes to occur in a carefully timed sequence: Cells proliferate and move to the correct spot, synapses form, neural circuits are refined, and neurotransmitters and their receptors grow. Neurotoxicants may slow, accelerate, or otherwise modify any of these processes. Says Philip Landrigan of New York's Mt. Sinai School of Medicine: "You end up with gaps in the wiring."

The idea that substances in the environment can harm the human brain is not new. In ancient Rome, miners were felled by what the medical literature of the time called "lead colic." The Mad Hatter in Lewis Carroll's Alice's Adventures in Wonderland comes from the 19th-century expression "mad as a hatter," a reference to mercury's effects on felt-hat makers. Over the past 70 years, adults and children around the world have been poisoned–and, in some cases, killed–by mercury in fish, PCBs in rice oil, a fungicide in seed grain, and a rat-killing agent in tortillas. After hearings in 1985, the House Committee on Science and Technology reported that there were 850 known neurotoxicants, any of which "may result in devastating neurological or psychiatric disorders that impair the quality of life, cripple and potentially reduce the highest intellect to a vegetative state." The report prompted virtually no action.

Today, however, the federal government is under increasing pressure from pediatricians, academics, and its own scientists, all clamoring for more testing of neurotoxicants. Agency officials are focusing on the following areas:

Pesticides. Organophosphate pesticides are domesticated versions of wartime nerve agents. The best known, Dursban and Diazinon, have been on the market since 1965 and 1956, respectively. The active ingredient of Dursban, chlorpyrifos, is found in some popular Raid sprays and Black Flag roach and ant killer. After re-examining the toxicity of chlorpyrifos, however, the EPA announced last week that it will ban nearly all household uses of it and restrict its use on tomatoes, apples, and grapes. The EPA found that Dursban could damage the brain. It also determined that children could receive up to 100 times the safe dose in some cases.

Diazinon, one of 37 other organophosphates under review, could be next. A preliminary EPA analysis recently found that a child could inhale up to 250 times the safe amount after a basic "crack and crevice" treatment by an exterminator. Linda Meyer, a toxicologist with Novartis, which makes Diazinon, says that the EPA extrapolated from a worst-case Novartis study–in which rats were placed in a chamber pumped full of the pesticide in aerosol form. As a result, Meyer says, "the risk for children is grossly overestimated." Novartis also notes that the EPA, in its draft analysis, states that animal studies of Diazinon have revealed "no evidence of abnormalities in the development of the nervous system."

The chemical industry prefers to police itself, when given a choice. But this approach seldom works, as evidenced by the EPA's failed attempt to restrict a pesticide known as chromated copper arsenic, or CCA. The compound is applied to pressure-treated wood and commonly found on decks and playground equipment. Since the late 1970s, EPA researchers have reported that CCA poses a special threat to pregnant women and children because it combines three neurotoxic compounds. People can be exposed to CCA by breathing fumes from unfinished wood during home repair or construction. As a structure ages, the compound may leach out into the dirt. In lower doses, according to numerous studies, CCA can impair intelligence and memory.

The EPA tried to restrict CCA in 1984, but homebuilders' and wood preservers' groups lobbied Congress so hard that the EPA retreated, asking only that retailers distribute advisories that the compound could endanger children. A decade later, the effort had gone nowhere. "We checked retailers," said John McCauley of the Kentucky Department of Agriculture, "and they had no clue what a consumer information sheet was." The EPA promised to decide on new restrictions by 1998, but officials now say the agency won't act until at least next year.

Mercury. When toxicologist David Brown helped prepare a mercury study for eight Northeastern states and three Canadian provinces in 1997, he knew that fish in the region's lakes would contain mercury; he just didn't know how much. As it turns out, the numbers were considerably higher than he expected. "The most pristine lakes," he says, "had the highest levels." Brown, formerly with the Agency for Toxic Substances and Disease Registry, did the math and concluded that a pregnant woman who ate a single fish from one of these lakes could, in theory, consume enough mercury to harm her unborn child.

But the Food and Drug Administration has no enforceable limit for mercury in fish–only a guideline of 1 part per million, which the National Academy of Sciences deems "inadequate to protect the developing fetus." Mike Bolger, chief of the FDA's Division of Risk Assessment, says the agency hasn't set a limit primarily because "the science has to be sorted out."

That shouldn't be surprising. For years, operators of the coal-fired power plants and trash incinerators responsible for most mercury pollution have been working to quash attempts to further regulate mercury. When the EPA concluded in 1996, for example, that more than 1.6 million Americans were at risk of mercury poisoning, industry lobbyists persuaded the agency not to make the report public for more than a year. It was released only after a group of senators complained. Lawmakers in states with substantial fishing and utility interests responded to the report by calling for yet another study, this time by the NAS. The new report, to be released next month, is expected to agree that current mercury levels are unsafe. But advocates for tight-er regulations aren't expecting any quick changes in policy. "The reason," says Democratic Sen. Patrick Leahy of Vermont, "is that mercury has a constituency in Washington."

There is also evidence that mercury found in some childhood vaccines can hamper development. Will Redwood, for instance, a 6-year-old from suburban Atlanta, seemed perfectly normal at birth. Within two years, he had stopped interacting with his family. By age 5, he was diagnosed with a mild form of autism. His mother, Lyn, a nurse practitioner, read that some childhood vaccines contain the mercury-based preservative thimerosal, cumulative doses of which could be harmful. She had a lock of Will's hair analyzed, and it was found to be loaded with mercury. In his first round of vaccinations alone, given when he was 2 months old, Will received 62.5 micrograms of mercury, or 125 times the EPA's daily limit. No one can say whether the vaccines–which contained the maximum amount of thimerosal–caused Will's autism. And experts say that parents should not withhold inoculations. In a statement last year, a group of manufacturers said that vaccines containing thimerosal "have been administered to billions of children and adults worldwide, with no scientific or medical data to suggest that it poses a public health risk." Still, the American Academy of Pediatrics raised enough questions last year that vaccine manufacturers have agreed to phase out thimerosal as soon as possible.

PCBs. The EPA banned the manufacture of polychlorinated biphenyls in 1977, but the compounds continue to haunt chil- dren. PCBs are a well-known cancer risk, but recent studies show that they can also impair learning and memory. EPA adviser Joseph Jacobson and Sandra Jacobson of Wayne State University reported in 1996 that children in Michigan with significant prenatal exposures were three times as likely as unexposed children to have low IQ scores and twice as likely to lag behind in reading comprehension.

Jeanette Champion says that her family's mental difficulties now make sense. She and roughly 5,000 others are suing St. Louis-based Solutia, which made PCBs in Anniston under the Monsanto name from 1935 to 1971, seeking compensation for what they claim are pollution-related maladies and property devaluation. One of the plaintiffs is Karen McFarlane, who lives near the plant with her husband and five children. McFarlane, 31, attended special school and has failed four times to get her GED. Six-year-old Derrick Hubbard has speech, vision, and memory problems. "If we go over his ABCs, he forgets them right away," says his mother, Dessa. Gadsden, Ala., psychiatrist Judy Cook is astounded at how many local children have IQs in the "borderline retarded" range and exhibit a penchant for violence. "These kids are different," she says. "Their wiring's not right."

In February, the Agency for Toxic Substances and Disease Registry reported that "PCBs in soil in parts of Anniston present a public health hazard" and that some adults and children had elevated amounts of the chemicals in their blood. Exposures, the agency speculated, "may still be occurring at high levels." The EPA has identified 22 other sites in Anniston that may contain dangerous amounts of PCBs, metals, and solvents. Solutia's Kaley concedes there may have been "historical exposure." But, he says, "We do not believe that people are currently being exposed." Nevertheless, the company has spent more than $30 million to clean up its Anniston site and surrounding land, bought out about 100 properties, and made a tentative settlement offer of $44 million to landowners along downstream waterways.

That prospect aside, there are still many unanswered questions about neurotoxicants and their effects on children. The dearth of data will continue to stymie parents like Terry DeCosta, who believes that pollution from the Tosco oil refinery in Clyde, Calif., contributed to the anger and attention problems in both her children. According to the EPA, Tosco discharged more than 1 million pounds of pollutants into the air in 1998, many of them neurotoxicants. When the DeCostas sued the refinery, however, their case was dismissed for lack of causation. Richard Jackson, of the Centers for Disease Control and Prevention, says that the easy work is done. "We've been able to find the things that are so toxic that they make people dizzy and fall down," he says. Now comes the harder work of identifying and regulating compounds that insidiously misarrange the brain. "I've heard people say we still don't have a smoking gun," says Chris De Rosa of the Agency for Toxic Substances and Disease Registry. "And then I've heard others say, 'Yes, but there are bullets all over the floor.' "

Article original published at: http://www.usnews.com/usnews/issue/000619/poison.htm