The Pros and Cons of DDT

     The widespread use of DDT began in 1945 to control agricultural pests and mosquitoes. DDT is extremely toxic to insects-both those that benefit the crops and those that destroy them. DDt is inexpensive, kills most pests, and provides lasting protection because it breaks down slowly. DDT is believed to have helped same millions of human lives. The military used it during WWII to control body licw and thus typhus fever, and th Wold Health Organization (WHO) used it to control mosquitoes and consequently the malaria they carry.
     In 1962m Rachel Carson wrote the book Slient Spring, which opened our eyes to the fact that long-term pesticide use in the United States could be harmful. Subsequent studies showed that DDT ( and other pesticides) can become concentrated in the food chain. DDt is known to have led to the decline of birds of prey, such as the bald eagle, because it causes thinning of egg shells. Adults then inadvertently crush the eggs when attempting to incubate them, killing the embryos before they hatch.
     Because of public concerns about DDT's effects on the environment and possible long-term effects on human health, th U.S. Environmental Protection Agency banned DDT in 1972. Recently, the United nations passed the international Persisten Organic Pollutants treaty to cut back on DDT in the environment by permitting its used only under strict regulations.
     Still, DDT is the most cost-effective chemical we have for preventing malaria because it kills the mosquitoes that carry the disease. According to the WHO, malaria causes 300 million acute illnesses and over 1 million deaths each year in the tropics, subtropics and portions of the Middle East. Researchers state in the Journal of Infectious Diseases, "Today, DDT is still needed for malaria control. If the pressure to abandon this effective insecticide continues, millions of additional malaria cases world-wide [will result]." So, should we continue to cut back on the use of DDT because of long term environmental effects on animals and people? Or should we consider allowing its use to help control malaria and prevent some of the many deaths from that disease that occur eash year?

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FROM YOUR OWN OPINION

1. Present regulations ban the manufacture and use of DDT in many, but not all, countries. Should it be banned everywhere? Why or why not?
2. Under what circumstances might the use of DDT be acceptable? Explain
3. Currently in the Unites States, the insecticide malathion is widely used to control mosquitoes that may carry Westi Nile virus. Although malathion breaks down more quickly than DDT, some evidence suggests it can be harmful to amphibians and fish. What date are needed before making decisions on continued widespread use of malathion?

From: Sylvia Mader, Inquiry Into Life