Environmental and Economic Costs of the Application of Pesticides Primarily in the United States 

Abstract 

An obvious need for an update and comprehensive study prompted this investigation of the complex environmental costs resulting from the nation’s dependence on pesticides. Included in this assessment of an estimated $12 billion in environmental and societal damages are analysis of pesticide impacts on public health; livestock and livestock product losses; increased control expenses resulting from pesticide-related destruction of natural enemies and from the development of pesticide resistance in pests; crop pollination problems and honeybee losses; crop and crop product losses; bird, fish, and other wildlife losses; and governmental expenditures to reduce the environmental and social costs of the recommended application of pesticides. The major economic and environmental losses due to the application of pesticides in the USA were: public health, $1.1 billion year-1; pesticide resistance in pests, $1.5 billion; crop losses caused by pesticides, $1.1 billion; bird losses due to pesticides, $2.2 billion; and ground water contamination, $2.0 billion.

 Keywords Agriculture · Costs · Crops · Environment · Livestock · Natural resources · Pesticide · Pesticide resistance · Public health

4.1 Introduction

 Worldwide, about 3 billion kg of pesticides are applied each year with a purchase price of nearly $40 billion per year (Pan-UK, 2003). In the U.S., approximately 500 million kg of more than 600 different pesticide types are applied annually at a cost of $10 billion (Pimentel and Greiner, 1997).

Despite the widespread application of pesticides in the United States at recommended dosages, pests (insects, plant pathogens, and weeds) destroy 37% of all potential crops (Pimentel, 1997). Insects destroy 13%, plant pathogens 12%, and weeds 12%. In general, each dollar invested in pesticide control returns about $4 in protected crops (Pimentel, 1997). Although pesticides are generally profitable in agriculture, their use does not always decrease crop losses. For example, despite the more than 10-fold increase in insecticide (organochlorines, organophosphates, and carbamates) use in the United States from 1945 to 2000, total crop losses from insect damage have nearly doubled from 7% to 13% (Pimentel et al., 1991). This rise in crop losses to insects is, in part, caused by changes in agricultural practices. For instance, the replacement of corncrop rotations with the continuous production of corn on more than half of the corn acreage has nearly resulted in an increase in corn losses to insects from about 3.5% to 12% despite a more than 1,000-fold increase in insecticide (organophosphate) use in corn production (Pimentel et al., 1991). Corn today is the largest user of insecticides of any crop in the United States. Most benefits of pesticides are based on the direct crop returns. Such assessments do not include the indirect environment and economic costs associated with the recommended application of pesticides in crops. To facilitate the development and implementation of a scientifically sound policy of pesticide use, these environmental and economic costs must be examined. For several decades, the U.S. Environmental Protection Agency pointed out the need for such a benefit/cost and risk investigation (EPA, 1977). Thus far, only a few scientific papers on this complex and difficult subject have been published. 

4.2 Public Health Effects 

4.2.1 Acute Poisonings

 Human pesticide poisonings and illnesses are clearly the highest price paid for all pesticide use. The total number of pesticide poisonings in the United States is estimated to be 300,000 per year (EPA, 1992). Worldwide, the application of 3 million metric tons of pesticides results in more than 26 million cases of non-fatal pesticide poisonings (Richter, 2002). Of all the pesticide poisonings, about 3 million cases are hospitalized and there are approximately 220,000 fatalities and about 750,000 chronic illnesses every year (Hart and Pimentel, 2002). 

4.2.2 Cancer and Other Chronic Effects

 Ample evidence exists concerning the carcinogenic threat related to the use of pesticides. These major types of chronic health effects of pesticides include neurological effects, respiratory and reproductive effects, and cancer. There is some evidence that pesticides can cause sensory disturbances as well as cognitive effects such as memory loss, language problems, and learning impairment (Hart and Pimentel, 2002). The malady, organophosphate induced delayed poly-neuropathy (OPIDP), is well documented and includes irreversible neurological damage. In addition to neurological effects, pesticides can have adverse effects on the respiratory and reproductive systems. For example, 15% of a group of professional pesticide applicators suffered asthma, chronic sinusitis, and/or chronic bronchitis (Weiner and Worth, 1972). Studies have also linked pesticides with reproductive effects. For example, some pesticides have been found to cause testicular dysfunction or sterility (Colborn et al., 1996). Sperm counts in males in Europe and the United States, for example, declined by about 50% between 1938 and 1990 (Carlsen et al., 1992). Currently, there is evidence that human sperm counts continue to decrease by about 2% per year (Pimentel and Hart, 2001). The U.S. data indicate that 18% of all insecticides and 90% of all fungicides are carcinogenic (NAS, 1987). Several studies have shown that the risks of certain types of cancers are higher in some people, such as farm workers and pesticide applicators, who are often exposed to pesticides (Pimentel and Hart, 2001). Certain pesticides have been shown to induce tumors in laboratory animals and there is some evidence that suggest similar effects occur in humans (Colborn et al., 1996). A UFW (2003) study of the cancer registry in California analyzed the incidence of cancer among Latino farm workers and reported that per year, if everyone in the U.S. had a similar rate of incidence, there would be 83,000 cases of cancer associated with pesticides in the U.S. The incidence of cancer in the U.S. population due to pesticides ranges from about 10,000 to 15,000 cases per year (Pimentel et al., 1997). Many pesticides are also estrogenic – they mimic or interact with the hormone estrogen – linking them to increase in breast cancer among some women. The breast cancer rate rose from 1 in 20 in 1960 to 1 in 8 in 1995 (Colborn et al., 1996). As expected, there was a significant increase in pesticide use during that time period. Pesticides that interfere with the body’s endocrine – hormonal – system can also have reproductive, immunological, or developmental effects (McCarthy, 1993). While endocrine disrupting pesticides may appear less dangerous because hormonal effects rarely result in acute poisonings, their effects on reproduction and development may prove to have far-reaching consequences (Colborn et al., 1996). The negative health effects of pesticides can be far more significant in children than adults, for several reasons. First, children have higher metabolic rates than adults, and their ability to activate, detoxify, and excrete toxic pesticides differs from adults. Also, children consume more food than adults and thus can consume more pesticides per unit weight than adults. This problem is particularly significant for children because their brains are more than 5 times larger in proportion to their body weight than adult brains, making chloinesterase even more vital. In a California study, 40% of the children working in agricultural fields had blood cholinesterase levels below normal, a strong indication of organophosphate and carbamate pesticide poisoning (Repetto and Baliga, 1996). According to the EPA, babies and toddlers are 10 times more at risk for cancer than adults (Hebert, 2003). 

Although no one can place a precise monetary value on a human life, the economic “costs” of human pesticide poisonings have been estimated (Table 4.1). For our assessment, we use the EPA standard of $3.7 million per human life (Kaiser, 2003). Available estimates suggest that human pesticide poisonings and related illnesses in the United States cost about $1 billion per year (Pimentel and Greiner, 1997).