Editing VG (nerve agent) (section)

==History==
By the 1950s, the use of [[Insecticide#Organophosphates|organophosphate insecticides]] was well established, despite their known toxicity to mammals.<ref>{{Cite journal |last1=Worek |first1=Franz |last2=Thiermann |first2=Horst |last3=Wille |first3=Timo |date=2020 |title=Organophosphorus compounds and oximes: a critical review |journal=Archives of Toxicology |volume=94 |issue=7 |pages=2275–2292 |doi=10.1007/s00204-020-02797-0 |issn=0340-5761 |pmc=7367912 |pmid=32506210|bibcode=2020ArTox..94.2275W }}</ref> For example, [[parathion]] had been developed in the 1940s and became widely used in agriculture despite its known oral toxicity.<ref>{{Cite web|url=https://www.fao.org/3/w5715e/w5715e05.htm |title=Parathion |website=fao.org |date=1997 |access-date=2025-03-18}}</ref> Many chemical companies continued to research this type of [[acetylcholinesterase inhibitor]], seeking to develop alternatives which had greater human safety while retaining their activity on pests. In 1952, Dr. Ranajit Ghosh, a chemist at [[Imperial Chemical Industries]] (ICI), investigated [[Organophosphorus compound|organophosphate]] [[Ester|esters]] of substituted amino[[Ethanethiol|ethanethiols]] and compared their properties to parathion, which ICI was already marketing as Fosferno.<ref name=JH50>{{Cite book |last=Calderbank |first=Alan |title=Jealott's Hill: Fifty years of Agricultural Research 1928-1978 |publisher=Imperial Chemical Industries Ltd. |year=1978 |isbn=0901747017 |editor-last1=Peacock |editor-first=F.C. |pages=49–54 |url=https://archive.org/details/jealottshillfift0000peac/page/49 |chapter=Chapter 6: Organophosphorus Insecticides |url-access=registration}}</ref><ref>{{Cite book |title=The Pesticide Manual |edition=8 |date=1987 |page=633 |editor-first1=Charles R. |editor-last1=Worthing |publisher=British Crop Protection Council |isbn=0948404019}}</ref>

Amiton was found to be much less toxic than parathion to many insects but was considerably more toxic to [[acarid]] pests such as the spider-mite ''[[Tetranychus|Tetranychus telarius]]''. [[Field trials]] demonstrated its utility against the red mite ''[[Panonychus ulmi]]'': a single treatment of 20&nbsp;ppm was shown to give season-long control. This led to plans to market the compound under the [[brand name|trade name]] '''Tetram''' but the oral LD<sub>50</sub> of 5&nbsp;mg/kg to rats meant that the compound was comparable to parathion in mammalian toxicity while having a more limited use, so its development was halted as not being commercially viable.<ref name=JH50/> It had been intended to [[Pesticide formulation|formulate]] it as its [[hydrogen oxalate]] ({{chem2|HC2O4−}}) salt, to minimise any hazard from the vapour.<ref>{{cite journal |doi=10.1002/jsfa.2740090808 |title=Amiton—a new acaricide and scalicide |date=1958 |last1=Baldit |first1=G. L. |journal=Journal of the Science of Food and Agriculture |volume=9 |issue=8 |pages=516–524 |url=https://www.cabidigitallibrary.org/doi/full/10.5555/19590500962 |bibcode=1958JSFA....9..516B |url-access=subscription }}</ref>

The [[British Government]] was aware of the extreme toxicity of organophosphate compounds and some of the ICI materials were sent to [[Porton Down]], [[Great Britain|Britain’s]] [[Chemical weapon|chemical weapons]] research facility, for evaluation. This led to the identification of a new class of [[Nerve agent|nerve agents]], later named [[Nerve agent#V-series|V (venomous) agents]]. Britain officially renounced chemical and biological weapons in 1956, but the United States continued research into this class, leading to the mass production of [[VX (nerve agent)|VX]]—a chemically similar but far more toxic compound—in 1961. Amiton was no longer pursued for chemical warfare or as a pesticide.<ref name="JH50" /><ref name=Borrett2003>{{Cite journal |last1=Borrett |first1=Veronica T |last2=Gan |first2=Tiang-Hong |last3=Lakeland |first3=Barry R |last4=Ralph Leslie |first4=D |last5=Mathews |first5=Robert J |last6=Mattsson |first6=Eric R |last7=Riddell |first7=Stuart |last8=Tantaro |first8=Vince |date=2003-06-27 |title=Gas chromatographic–mass spectrometric characterisation of amiton and the recovery of amiton from concrete, paint, rubber and soil matrices |journal=Journal of Chromatography A |volume=1003 |issue=1 |pages=143–155 |doi=10.1016/S0021-9673(03)00774-X |issn=0021-9673}}</ref><ref>{{cite web |title=A Short History of the Development of Nerve Gases |url=http://www.mitretek.org/AShortHistoryOfTheDevelopmentOfNerveGases.htm |url-status=dead |archive-url=https://web.archive.org/web/20061112085443/http://www.mitretek.org/AShortHistoryOfTheDevelopmentOfNerveGases.htm |archive-date=November 12, 2006 |access-date=2025-03-18 |work=Mitrek Systems}}</ref>