DDT

Dichlorodiphenyltrichloroethane (DDT) is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. DDT was first synthesized in 1874 by the Austrian chemist Othmar Zeidler. DDT's insecticidal action was discovered by the Swiss chemist Paul Hermann Müller in 1939. DDT was used in the second half of World War II to limit the spread of the insect-borne diseases malaria and typhus among civilians and troops. Müller was awarded the Nobel Prize in Physiology or Medicine in 1948 "for his discovery of the high efficiency of DDT as a contact poison against several arthropods". The World Health Organization's (WHO) anti-malaria campaign of the 1950s and 1960s relied heavily on DDT and the results were promising, though there was a resurgence in developing countries afterwards.

The widespread use of DDT after World War II soon raised environmental concerns, highlighted in the United States by Rachel Carson's 1962 book Silent Spring, which helped spur public opposition and contributed to the 1972 US ban on its agricultural use. The restrictions by governments worldwide that followed were also driven by growing evidence of environmental, wildlife and health harm, and the evolution of insect resistance to DDT. These measures aided the recovery of endangered species. Agricultural use was later largely banned worldwide under the Stockholm Convention on Persistent Organic Pollutants of 2004, although limited public-health use for malaria control remains permitted under WHO guidelines.