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Pesticides and Children: Wargo's book examines how science and law have failed to prevent nation's 'toxic legacy'

New federal standards for pesticide residues on food do not go far enough to safeguard public health -- especially the health of children, according to Professor John P. Wargo, author of "Our Children's Toxic Legacy: How Science and Law Fail to Protect Us from Pesticides," published this month by Yale University Press.

Children may be exposed to more pesticides in their diets than adults because they consume more of some foods such as fruits, vegetables and juices. Yet most residue limits are based on an average adult diet, Professor Wargo notes. Furthermore, children's rapid growth and development may make them more vulnerable to the toxic effects of pesticides, he adds.

"While the new federal standards President Clinton signed into law in August are important steps toward food safety, they fail to take into account the cumulative nature of pesticide exposures," says Mr. Wargo, who is associate professor of environmental risk analysis at the School of Forestry and Environmental Studies and made key contributions to two major National Academy of Sciences studies of pesticide risks conducted in the last decade. "Pesticides are used legally not only on food crops, forests, lawns and gardens, but also on golf courses, along highways, and in swimming pools, wallpaper, shower curtains, dry-cleaning fluids, rugs, paints and some shampoos."

Hundreds of pesticides have been licensed for use on foods in the past 50 years despite only a vague understanding of how they affect health -- thereby constituting "an uncontrolled human experiment," he contends. Nearly one-third of these chemicals are suspected of causing cancer in laboratory animals. Another third are capable of disrupting the human nervous system. Many others are suspected of interfering with the endocrine system, which regulates growth and development.

In his book, Professor Wargo outlines scientific principles for assessing risks to children, nursing mothers, the elderly and other special population groups; suggests how to communicate those risks so people can make informed decisions about what they eat; and proposes fundamental legal reforms and methods of managing the unwieldy mix of licensed toxins.

$6-billion-a-year industry

Regulating the $6-billion-a-year U.S. pesticide industry is no easy task, concedes Professor Wargo, who is also affiliated with the political science department and the Institution for Social and Policy Studies. The government's practice of licensing pesticides one at a time has produced an unwieldy system of 9,300 different limits for the 325 pesticides allowed on foods. Because limits are set for the use of each chemical on each food, as many as 70 to 100 different licenses can exist for a single pesticide.

"The 10 separate federal statutes governing pesticide exposure create a confusing maze of ineffectual regulations," Professor Wargo says. "The result is a fractured body of law based on uncertain science that has created a legacy of risk for our children and perhaps their children."

A loophole in federal regulations makes it possible for DDT and other pesticides banned from use in the United States to be exported to other countries, where they can be sprayed on food crops imported back into the United States. Furthermore, manufacturers are protected from disclosing to the public that they export banned pesticides, he says, so consumers are unaware of this "boomerang" effect.

Also in his book, Professor Wargo notes:

• Pesticide purchases in America alone total 2.5 billion pounds a year out of nearly 6 billion pounds purchased worldwide. Nearly 5 billion pounds of DDT have been used indoors and outdoors worldwide since it was introduced in 1939. DDT accumulates in the food chain and has been linked to disruption of the human endocrine system.
• The United States imports nearly 600 different foods from about 150 countries. On average, the FDA conducts one pesticide residue test for every 2 million pounds of imported food. Of the 10 billion bananas shipped into the U.S. annually between 1984 and 1991, on average only 167 banana samples were monitored for residues each year.
• In 1986, 73 of 186 imported food shipments containing illegal pesticide residue levels were allowed to reach the marketplace.
• A 1989 National Academy of Sciences study found that farms that do not use synthetic insecticides, herbicides or fungicides may be more profitable than farms that do. In fact, between 1945 and 1989, insecticide use in the U.S. increased tenfold while crop losses from insects almost doubled, from 7 to 13 percent. "Insecticide use may actually increase crop losses over time as insects develop resistance," Professor Wargo says. "Like the overuse of antibiotics, overuse of pesticides could leave us unprotected when we really need them for severe insect infestations."
• Until the early 1990s, toxic mercury was added to some paints, which can be inhaled when airborne and ingested when paints chip, flake and peel. Rugs may be impregnated with compounds to kill insects and mildew, and rugs can absorb pesticides sprayed indoors.
• A 1989 study by the Children's Cancer Study Group found that children whose fathers were exposed to pesticides on the job were more likely to contract leukemia.
• The cost of monitoring pesticide residues in municipal water supplies recently was estimated to be more than $5 billion a year, a cost passed on to the public by those who sell and use pesticides
• About half of all U.S. pesticides, by weight, are applied to corn, which surpassed cotton in 1982 as the crop sprayed with the most pesticides.

'Reasonable certainty of no harm'

Evidence that legislators are beginning to heed scientific warnings came this summer when more stringent pesticide standards were approved by Congress. The new legislation creates a single standard for residues on both fresh and processed foods, requiring "reasonable certainty of no harm" from exposure over a lifetime. It also sets an exposure limit that better protects children and infants, and requires the EPA to make booklets available at grocery stores within two years explaining how to avoid harmful pesticide exposure.

"An extra safety factor when it comes to the health of children makes a lot of sense," Professor Wargo says, "because it shifts the burden of proof to the private sector to demonstrate the safety of the pesticide. The reverse strategy -- assuming that the pesticide is safe until it is proven unsafe -- is twisted logic for managing childhood exposure to toxins."

The new legislation does away with pesticide provisions in the Delaney Clause, which since 1958 had prohibited even trace amounts of carcinogenic pesticides on processed foods while allowing residues on fresh foods, based on their value in guarding the food supply. The Delaney Clause was widely considered to be scientifically insupportable and unenforceable, says the Yale professor.

While the new safety standard is being claimed as a victory by environmentalists, it also is a victory for pesticide manufacturers, he says, because numerous carcinogenic pesticides the EPA was forced to ban by a recent court decision can remain in use under the new law.

He warns that the new law "will shift conflict over pesticide regulation from Congress to the halls of the EPA. Pesticide manufacturers, judging from their wide support for the new legislation, are banking on their ability to control the EPA risk- assessment process, especially since manufacturers provide most of the data used by EPA to estimate health risks."

Professor Wargo also foresees "paralysis through analysis" if case-by-case risk assessment of pesticides bogs down. "I seriously doubt that the 10-year time frame set by federal law for assessing the risks of all the existing pesticides is realistic," he says. "The absence of accurate risk assessments has had the effect of slowing removal of suspect chemicals from the marketplace while delaying the introduction of new pesticides that are less risky."

The new law also prohibits states from adopting more rigorous standards than the federal government, a restriction that makes little sense just when scientists are beginning to understand regional risk variations, he says.

"The surest way to undercut the intent of the new risk-based standard would be to further restrict funds for residue testing, food consumption surveys and toxicity testing; or to fail to provide EPA with enough staff to interpret data," he adds.

To insure protection of children, Professor Wargo recommends:

• Increased funding for research into farming methods that require no synthetic pesticides, and redirecting federal subsidies to encourage farmers to switch to organic farming.
• Better tracking of pesticide use, which would make it possible to more accurately estimate risks associated with childhood exposure to pesticide mixtures.
• Public disclosure of time and location of significant pesticide use, similar to the chemical disclosures now required by the Toxic Release Inventory regulations.
• Adequate funding for monitoring residues on foods, in drinking water and in schools.
• Uniform food labeling standards that clearly identify foods grown with pesticides.
• Stepped up consumer education about ways to reduce pesticide exposure, such as improved organic labeling and environmentally friendly alternatives for household and garden insecticides.

Professor Wargo makes it clear that he does not advocate a pesticide-free society. "DDT has prevented millions of deaths from malaria, and insect control has boosted worldwide food production. But it seems reasonable not to use DDT where there is no malaria and to use the least toxic and the least persistent chemicals available to control serious pest and public health problems," he says.

How to protect children from pesticide exposures

Professor John P. Wargo, the father of two young children and the author of "Our Children's Toxic Legacy: How Science and Law Fail to Protect Us from Pesticides," published this month by Yale University Press, gives these tips on ways to reduce your children's pesticide exposure:

• Look in the refrigerator and see what your young children eat the most -- fruit juices, applesauce, bananas. Consider purchasing organically grown produce and juices. Look for organic products that comply with state certification programs, such as those in California.
• If you drink well water, have your water tested before adding it to infant formula or juice concentrates. Get together with neighbors to discuss reducing or eliminating pesticides on lawns. Also inquire about pesticide use at nearby industries and institutions that might contaminate your water. Consult local or state health officials about filtering systems, if needed. Even low levels of water contamination may lead to significant childhood exposure.
• Tell your grocery store manager you are interested in organic labeling and organically grown produce, or contact your local Agricultural Extension Service for a list of certified organic growers in your state. Better yet, grow your own organic food.
• If you live where Lyme disease is prevalent, conduct daily tick checks instead of spraying children. Manage pets carefully to avoid bringing ticks inside. Ask your veterinarian to recommend low-toxicity flea collars and other pet-care products.
• Cut back vegetation around the house to help prevent insect infestations.
• Avoid using pressure-treated lumber. Ask your local building supply manager to recommend woods that are naturally rot resistant, such as cedar.
• Try to avoid all insect sprays inside the house, especially if you have small children or are pregnant.
• Get involved with your schools and find out what herbicides and pesticides they are using. Look for nontoxic substitutes on playing fields and in classrooms. Encourage your school system to develop a plan for reducing the use of toxic substances.