Insecticide

Name:
Insecticide
Detailed information:
A type of pesticide designed to control insect life that is harmful to humans, either directly as disease vectors or indirectly as destroyers of crops, food products, or textile fabrics. General types are as follows: (1) Inorganic: arsenic, lead, and copper (inorganic compounds and mixtures); the use of these has diminished sharply in recent years because of the development of more effective types less toxic to humans. (2) Natural organic compounds, such as rotenone and pyrethrins (relatively harmless to humans since they quickly decompose to nontoxic compounds), nicotine, copper naphthenate, and petroleum derivatives. (3) Synthetic organic compounds: (a) chlorinated hydrocarbons such as DDT, dieldrin, endrin, chlordane, lindane, p-dichlorobenzene; (b) the organic esters of phosphorus (the parathions and related substances). (4) Of comparatively recent development are pyrethroids, or insect growth regulators, which act as neurotoxins, preventing larvae from becoming adult forms (juvenile hormones); and metabolic inhibitors, e.g., imidazole, which function as structural antagonists.

Hazard:

Insecticides are toxic to humans in varying degrees. Among the safest are the pyrethrins, rotenone, and methoxychlor. Most of the organophosphorus types (parathion and related compounds) are highly toxic but are reasonably biodegradable. The chlorinated hydrocarbons resist biodegradation; their use has been restricted and in some cases (DDT) banned for agricultural application, due to their harmful ecological effects. EPA is constantly monitoring new insecticides and issues warnings or restrictions on their use; its approval is required before they can be registered.

See Pesticide; Fumigant; Herbicide; Rodenticide; Repellent.