Issues: Health

CHLORPYRIFOS: HOW CHILDREN ARE EXPOSED TO PESTICIDES FROM MULTIPLE SOURCES

Current standards established by the U.S. Environmental Protection Agency to protect children from exposure to hazardous pesticides fail to consider children's cumulative exposure to the same pesticide from multiple sources. Although separate standards exist for minimizing exposure in food and water, for example, none currently take into account that on any given day a child may be exposed to the same pesticide from several sources. With the enactment of the Food Quality Protection Act of 1996, the EPA is now required to consider cumulative routes of exposure to a pesticide when setting tolerances.

Examine the various ways a child can be exposed to chlorpyrifos, the most widely used insecticide in the United States.^[77] Under the trade name Lorsban, chlorpyrifos is applied to numerous food crops; under the trade name Dursban, it is widely used around the home and garden. Over 17 percent of U.S. households use chlorpyrifos products, primarily as a treatment for termites underneath homes and buildings, between cracks and crevices for cockroach control, as a fogging agent against fleas, and in pest control strips.^[78] Not counting synergists (chemicals added to pesticide products to increase the effect of the pesticide ingredient), chlorpyrifos was the fourth most common insecticide found in U.S. homes in a 1990 EPA survey.^[79] Chlorpyrifos is frequently detected in indoor air.^[80] Chlorpyrifos residues can remain in homes for years after treatment and, in one study, have actually been found to increase in air over time.^[81] Of particular concern is hand spraying of aqueous chlorpyrifos formulations directly to household surfaces for control of fleas. Monitoring of indoor air and surfaces such as carpets after such spraying has detected chlorpyrifos at levels high enough for infants, who spend considerable time crawling on the floor, to absorb a dose five times above levels that cause toxicological effects.^[82]

Children are exposed to chlorpyrifos residues in food. According to a 1994 monitoring of ready-to-eat foods conducted by the Food and Drug Administration, chlorpyrifos was the second most commonly detected pesticide in food. The FDA's sample included many foods eaten by infants and children.^[83] Chlorpyrifos residues may also appear in drinking water; it has been found in the groundwater of nine states, in the surface water of two states, and in rainwater and fog in California.^[86]

Chlorpyrifos appears frequently as an illegal residue on foods for which its use is prohibited.^[87] The most recent, highly visible case involved chlorpyrifos contamination of Cheerios. In 1994, FDA sampling led to the discovery that a commercial applicator under contract to General Mills, Inc. had illegally treated 21 million bushels of raw oats with chlorpyrifos-ethyl as a substitute for chlorpyrifos-methyl, the formulation of chlorpyrifos legally registered for use on oats.^[88] Fifty-five million packages of General Mills cereals made from contaminated oats were eventually landfilled or incinerated.^[89]

Both acute and chronic illness are common concerns following exposure to chlorpyrifos. As an organophosphate insecticide, chlorpyrifos is acutely toxic to the nervous system and is associated with numerous poisonings. According to a recent EPA analysis, chlorpyrifos is one of the leading causes of acute insecticide poisoning incidents in the United States.^[90] In California between 1984 and 1990, chlorpyrifos was responsible for the highest number of physician reported illnesses related to structural pest control activities.^[91] As many as 11,000 children under age five were reported to Poison Control Centers between 1985 and 1992 to have been exposed to chlorpyrifos.^[92]

In terms of chronic health effects associated with chlorpyrifos, peripheral neuropathy is of greatest concern. Peripheral neuropathy is a condition involving the nerves of the arms and legs that results in burning and tingling, muscle weakness, and difficulty with coordinated movement. In 1995, the manufacturer of chlorpyrifos, DowElanco, agreed to pay $876,000 for failing to disclose to the U.S. EPA information about adverse effects caused by exposure to chlorpyrifos.^[93] The consent agreement covers 327 violations involving claims of neurotoxicity and other health effects associated with chlorpyrifos exposure, including at least 215 personal injury claims between 1984 and 1995.^[94]

In January 1997, the EPA completed a review of the potential risks associated with household and termiticide uses of chlorpyrifos. As a result, DowElanco agreed to the EPA's plan for providing safer use of the chemical, including the withdrawal of uses for indoor flea control, indoor total release foggers, pet care, and paint additives.