The Health Effects of Pervasive Illegal Pesticides in Food
Forbidden Fruit | Illegal Pesticides in the US Food Supply: The Health Effects of Pervasive Illegal Pesticides in Food
Most pesticides are limited to use on certain crops because additional uses, such as the illegal uses identified in this report, cause the total exposure to the pesticide to exceed federal health or environmental standards. The 826 violations identified in this report are a serious public health concern because, in total, they represent a breach of the pesticide food safety system that cannot be dismissed as negligible.
For most heavily used pesticides, the EPA has reviewed the available toxicity studies and has calculated an acceptable daily dose for the pesticide based on total exposure from all food sources. Pesticide tolerances are granted or denied as a result of this review. The tolerances themselves do not, however, explicitly consider the vulnerability of infants and small children, nor do they account for other routes of exposure to pesticides, such as water or home uses. In fact, the tolerances for many heavily used pesticides exceed federal health standards by a factor of 100 or more (Fisher 1992a, 1992b). Some pesticides, such as the insecticide chlorpyrifos, are commonly found in food and are widely used around the home and garden.
It is hard to argue that an occasional, isolated illegal use of a pesticide presents a major public health threat. In contrast, the results of this study show that illegal pesticides are pervasive throughout the fruit and vegetable supply, and that the totality of the exposure undermines the credibility of the pesticide food safety system in the United States.
Exposure to Multiple Pesticides in Food Presents Serious Health Risks to Young Children
A five-year National Academy of Sciences study of pesticides in the diets of infants and children explored this issue in detail when it examined the toxicological significance of simultaneous exposure to different pesticides found in food.
Using advanced computer models designed to simulate the real world probability of multiple exposures to pesticides in food, the Academy committee examined the health consequences of routine consumption of eight different foods with residues of five pesticides commonly detected by the FDA. The five pesticides were chosen because they all inhibit the production of acetylcholinesterase in the human nervous system, contributing additively to the same toxic effect in children. The nervous system was chosen because it is incompletely developed in infants, toddlers, and young children and thus more sensitive to the effects of neurotoxins than the nervous system of adults.
"Although the data are weak, the committee estimated that for some children exposure could be sufficiently high to produce symptoms of acute organophosphate pesticide poisoning." (NRC 1993, p. 7)
The data supporting this calculation and conclusion are "weak" only because the survey underpinning the food consumption estimates is over 15 years old, and for two-year olds, the individual food consumption estimates are derived from a smaller than desirable sample. In fact, the NAS calculation understates exposure to the pesticides causing this neurotoxic effect for two reasons. First, approximately 20 additional pesticides routinely found in food, but not considered by the NAS, cause the same effect, and second, the committee only looked at exposure to these compounds in eight foods, ignoring other food and environmental sources.
In spite of any reservations that the committee may have had about certain aspects of the data contained in its analysis, its recommendations for improvements in the way the EPA currently assesses the risk of pesticides were unusually clear:
"All exposure to pesticides--dietary and nondietary--need to be considered when evaluating the potential risks to infants and children." (NRC 1993, p. 11).
And, "Estimates of total dietary exposure should be refined to consider intake of multiple pesticides with a common toxic effect." (NRC 1993, p. 11)
If nothing else, the Academy's analysis confirms the fact that routine exposures to combinations of different pesticides at levels that commonly occur in food can cause toxic effects in infants and children. Adding 66 different illegal pesticide uses to this mix only makes matters that much worse.