(F.A.C.T.) Fair Agricultural Chemical Taxes
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| Pimentel notes in 1993 that, "...a large body of evidence suggesting pesticides can produce immune dysfunction has been accumulated over recent years from animal studies."119 A March 1999 study focused on the combined effects of three commonly used farm chemicals (aldicarb, atrazine, and nitrate) at concentrations typically found in groundwater. Mice who were given drinking water laced with the chemicals exhibited altered immune, endocrine, and nervous system function. Effects were most noticeable when a single pesticide was combined with nitrate fertilizer.120
In response to this growing body of evidence, the National Cancer Institute and other federal agencies have launched a major, multi-year study. The Agricultural Health Study (AHS) will interview and follow some 90,000 individuals in an attempt to better understand the health outcomes associated with agricultural chemical exposures. That study is not likely to settle the question of health effects from pesticide exposure, but it is hoped that it will significantly advance our understanding of this complex and important field of science.121 Pesticide Residues in Foods In a recent report by the Consumers Union, which analyzed pesticide residue data collected by the USDA from 1994-97, more than 27,000 food samples were evaluated for the presence of pesticide residues and rated for their toxicity. Toxicity is computed as an index integrating the frequency of pesticide detection, the levels of residues present, and the relative acute (LD50) and chronic (RfD- reference dose) toxicity of the pesticides present. Individual food samples often had multiple residues with up to thirty-seven different pesticide chemicals detected in apples and more than twenty found in peaches, pears, and spinach. Toxicity was repeatedly quite high in fresh peaches, frozen and fresh winter squash, apples, grapes, spinach, pears, and green beans in U.S. and imported crops. On the whole, imported foods were not more contaminated than U.S. crops, but exceptions to this included: Chilean grapes, Canadian and Mexican carrots, Mexican broccoli and tomatoes, Argentine and Hungarian apple juice, and Brazilian orange juice (in order of toxicity).123 Wildlife can be profoundly affected by loss of habitat and contaminated food due to pesticides. This can result in a variety of weaknesses and illnesses that impair an animal's ability to survive or reproduce. It is estimated that of the roughly 672 million birds exposed annually to pesticides on U.S. agricultural lands, 10 %, or 67 million, are killed.124 This staggering number is a conservative estimate that takes into account only birds that inhabit farmlands, and only birds killed outright by ingestion of pesticides. The full extent of bird fatalities attributable to pesticides is extremely difficult to determine because most deaths go undetected. Nevertheless, sobering numbers of dead birds have been documented. For example, in 1995, the pesticide monocrotophos, sprayed to kill grasshoppers, was responsible for the deaths of at least 20,000 Swainson's Hawks in Argentina. In 1989, the Environmental Protection Agency reported that carbofuran was estimated to kill at least 1-2 million birds in the United States each year.
So far, about forty active ingredients in pesticides have been found to be lethal to birds. The active ingredients that have proven to be deadliest to birds include diazinon, phorate, carbofuran, monocrotophos, isofenphos, chlorpyrifos, aldicarb, azinphos-methyl, and parathion.125 Endocrine disruption has been the focus of an increasing number of scientific investigations during recent years. A number of agricultural pesticides, such as atrazine, 2,4-D, and carbaryl, are suspected of causing disruption to the endocrine system.126 Aquatic wildlife appear to be particularly vulnerable, but terrestrial wildlife are impacted as well. The U.S. Geological Survey found that blood concentrations of sex steroid hormones and egg proteins (vitellogenin) were higher in common carp and largemouth bass located in contaminated versus reference sites.127 These indicators may be associated with reproductive impairment. Problems being investigated include reduced penis size in juvenile male otters of the Columbia River, non-descended testicles in male Florida panthers, nonfunctional testes in male American alligators in Florida, and masculinized female mosquito fish.128 Beneficial insects ("good bugs") are also negatively impacted by pesticides and some harmful insects ("bad bugs") are showing increasing resistance to insecticides.129 The continuous use of pesticides causes a steady decline in the populations of beneficial insects that are naturally present on farms and in surrounding areas, and that prey on damage-causing pests. The decline in the "good bugs", such as ladybeetles, lacewings, parasitic wasps, minute pirate bugs, and all kinds of spiders results in the need to use increasing amounts of pesticides to control the "bad bugs", such as aphids, stink bugs, army beet worms, and cucumber beetles. To complicate matters further, more than 500 insects and mite species have become resistant to one or more pesticides, thus requiring either higher quantities or more toxic chemicals to manage them. This pattern of escalated use then further decimates the "good bugs" resulting in the sole reliance on pesticides or the "pesticide treadmill." Of course, insecticides are the most toxic class of pesticides to insects. In addition, the fungicide benomyl is acutely toxic to earthworms which are highly beneficial to soil health.130 Water There is little argument that overall, our current agricultural production system has a profound impact on water quality. The contamination of rivers, streams, and groundwater with pesticide residues has been well-documented for more than a decade. Although most of the research and concern have been primarily focused on pesticide use and impacts, synthetic fertilizer use has also been shown to contaminate ground and surface waters. Frequently, farmers apply more fertilizer than their plants can use. The National Research Council found that of all nitrogen and phosphorous applied in the U.S., 1/3 of nitrogen and almost 2/3 of phosphorous is not used by crops and become sources of local and regional water quality problems.131 History of Documenting Agri-Chemical Impact on Water — As early as the 1960s, Carson cited information about contaminated waters in watersheds affected by aerial spraying of pesticides in Silent Spring. Commonly used insecticides were found in California estuaries in the late 1960s,132 and studies dating back to the 1950s have detected pesticide residues in U.S. rivers. Still, the potential for rainwater to "run off" farm fields or suburban lawns and carry with it eroded soils and pesticides was dismissed for many years. While Rachel Carson raised the specter of groundwater contamination early on, the federal government commission that responded to her warnings did not heed her concerns.
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