DDT (dichlorodiphenyltrichloroethane) is a synthetic bug killer known as an organochlorine pesticide. It was developed during the 1940s to kill mosquitos and prevent insect-borne diseases such as malaria. Farmers later sprayed it on crops to control insects.
The U.S. banned DDT in 1972 because of potential health risks. However, the chemical and its breakdown products, or metabolites, can persist in the environment for many years.