Müller, Paul Hermann (1899-1965)

Swiss chemist who was awarded a Nobel Prize for Physiology or Medicine in 1948 for his discovery of the first synthetic contact insecticide, DDT, in 1939.

Müller was born in Olten, Solothurn, and studied at Basel. He went to work for the chemical firm of J R Geigy, researching principally into dyestuffs and tanning agents; he subsequently joined the staff of Basel University.

In 1935 Müller started the search for a substance that would kill insects quickly, but have little or no poisonous effect on plants and animals, unlike the arsenical compounds then in use. He concentrated his search on chlorine compounds and in 1939 synthesized DDT.

The Swiss government successfully tested DDT against the Colorado potato beetle in 1939 and by 1942 it was in commercial production. Its first important use was in Naples, Italy, where a typhus epidemic in the period 1943-44 was ended when the population was sprayed with DDT to kill the body lice that are the carriers of typhus.