Studies have also shown various synthetic pyrethroids can harm immune and reproductive systems. Dr. Philip Landrigan, chairman of the Department of Community and Preventative Medicine at the Mt. Sinai Medical School in New York City, says the average U.S. medical student gets only about six hours of training in environmental medicine in four years of medical school, and almost none of that focuses on pesticide toxicity. In order to work, the insecticide must hit the mosquito directly, says Dr. David Pimentel, an insect ecologist at Cornell University. But since spray trucks are only fogging the street side of buildings, he doubts that more than one-tenth of 1 percent of the poison is actually hitting its target. None of the dozens of stories reviewed for this piece mentioned there are much safer and more effective alternatives for dealing with adult mosquitoes.
Prevention works best and is the least toxic way to control mosquitoes.
Preventive measures include draining stagnant water where the pests breed, and applying less dangerous larvacides to lakes, ponds, drainage ditches and other areas to stop mosquito eggs from hatching. If communities don't have prevention programs in place, a range of new technology is now available to deal with adult mosquitoes. Or, if officials are wedded to the chemical approach, a new generation of affordable, biologically based substances are now available. However, these biopesticides require greater human skill and attention to the biology of the target pests than broad-spectrum synthetic pesticides. The Pew Environmental Health Commission at the Johns Hopkins School of Public Health points out that chronic illness is now the No. 1 cause of death in the United States.