demeton

Demeton, sold as an amber oily liquid with a sulphur like odour under the name Systox, is an organophosphate derivative causing irritability and shortness of breath to individuals repeatedly exposed. It was used as a phosphorothioate insecticide and acaricide and has the chemical formula C8H19O3PS2. Although it was previously used as an insecticide, it is now largely obsolete due to its relatively high toxicity to humans. Demeton consists of two components, demeton-S and demeton-O in a ratio of approximately 2:1 respectively. The chemical structure of demeton is closely related to military nerve agents such as VX and a derivative with one of the ethoxy groups replaced by methyl was investigated by both the US and Soviet chemical-weapons programs under the names V-sub x and GD-7.

== History == Demeton, under the name Systox, was introduced by Bayer in 1951. It was the first systemic insecticide. It was used against aphids, thrips, and sawflies in the agriculture sector. Demeton was distributed through the soil or sprayed over crops and was used widely. In 1982, 162,000 lbs of demeton was used for insecticidal purposes. The registration of the active ingredient of demeton was canceled by the United States Environmental Protection Agency in 1998. Demeton is no longer used in registered pesticides in most countries, including the United States and the Netherlands.