Dieldrin is a chlorinated hydrocarbon originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide

Insecticide

An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...

. Dieldrin is closely related to aldrin

Aldrin

Aldrin is an organochlorine insecticide that was widely used until the 1970s, when it was banned in most countries. It is a colourless solid. Before the ban, it was heavily used as a pesticide to treat seed and soil...

, which reacts further to form dieldrin. Aldrin is not toxic to insects; it is oxidized in the insect to form dieldrin which is the active compound. Both dieldrin and aldrin are named after the Diels-Alder reaction

Diels-Alder reaction

The Diels–Alder reaction is an organic chemical reaction between a conjugated diene and a substituted alkene, commonly termed the dienophile, to form a substituted cyclohexene system. The reaction can proceed even if some of the atoms in the newly formed ring are not carbon...

 which is used to form aldrin from a mixture of norbornadiene and hexachlorocyclopentadiene

Hexachlorocyclopentadiene

Hexachlorocyclopentadiene is an organochlorine compound that is a precursor to several pesticides. This colourless liquid is an inexpensive reactive diene. Many of its derivatives proved to be highly controversial, as studies showed them to be persistent organic pollutants. Collectively, the...

.

Originally developed in the 1940s as an alternative to DDT

DDT

DDT is one of the most well-known synthetic insecticides. It is a chemical with a long, unique, and controversial history....

, dieldrin proved to be a highly effective insecticide and was very widely used during the 1950s to early 1970s.