This organochlorine insecticide can be considered as the pesticide of the greatest historical significance, due to its effect on the environment, agriculture, and human health. First synthesized by a German graduate student in 1873, it was rediscovered by Dr. Paul Mueller, a Swiss entomologist, in 1939 while searching for a long-lasting insecticide for the clothes moth. DDT subsequently proved to be extremely effective against flies and mosquitoes, ultimately leading to the award of the Nobel Prize in medicine for Dr. Mueller in 1948. Effective January 1, 1973 the Environmental Protection Agency (EPA) officially canceled all uses of DDT, but not before more than 1 billion kilograms of DDT had been introduced into the United States. Like endosulfan, DDT disrupts the delicate balance of sodium and potassium within neurons. The pesticide is effective against a wide spectrum of insects in the agricultural arena and also mosquitoes that transmit malaria and yellow fever as well as body lice that carry typhus.