NCPA - National Center for Policy Analysis


May 19, 2004

Over the past few years in St. Louis, New York and other areas, pesticides have been used to tame the West Nile virus, a mosquito-borne disease which can lead to flu-like symptoms, and in a few cases, death. But many environmental groups want to halt the use of pesticides used to reduce exposure to mosquito-borne illnesses, according to a study from the Competitive Enterprise Institute.

Environmental activists claim the risks of pesticide use outweigh the benefits, but the data shows otherwise:

  • Activists claim pesticides cause cancer in humans -- but the World Health Organization reports that only about 2 percent of cancer cases are attributable to any form of environmental pollution, whereas diet and cigarette smoking contribute to about 65 percent of cancer cases.
  • Specifically, activists claim that pesticide use contributes to "estrogenic" cancers such as breast and prostate cancer; however, research has not proven this link -- indeed, prostate cancer rates have declined by 11 percent and leveled off since 1992.
  • Activists downplay the seriousness of West Nile virus; however, in New York alone, there were a reported 62 cases and 7 deaths in 2002 -- while these numbers are modest, the unpredictability of the virus raised concerns with health officials.

Moreover, reports that pesticides kill more birds than West Nile are shaky. In studying New York's bird death rate in 2001, science writer Steven Milloy concluded:

  • Out of a sample 3,216 birds, about two-thirds of them died from natural diseases (1,263 deaths were from West Nile virus) -- only 219 deaths were pesticide-related, with the majority of them caused by intentional poisoning or illegal use of pesticide products.
  • Bird Watcher's Digest reported that in 2002, 400 great horned howls were found dead in the Midwest as a result of West Nile virus, and that there could have been as many as 40,000 to 400,000 more unreported cases.

Thus use of pesticides can not only prevent human diseases, but those of animals.

Source: Angela Logomasini, "Pesticides and the West Nile Virus -- An Examination of Environmentalist Claims," Competitive Enterprise Institute, March 2004.


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