Lewisite chlorovinyl dichloroarsine

SYNS (2-CHLOROETHENYL) ARSONOUS DICHLORIDE P-CHLOROVINYLBICHLOROARSINE 2-CHLOROVINYLDICHLOROARSINE (2-CHLOROVINYL)DICHLOROARSINE DICHLORO(2-CHLOROVINYL)ARSINE n LE STSITE n LEWISITE (ARSENIC COMPOUND)... 

Yellow Cross Gases. This includes substances with a low vapour tension and high toxic and vesicatory power dichloroethyl sulphide (mustard gas), chlorovinyl dichloroarsine (lewisite), etc. 

Lewisite (2-chlorovinyl dichloroarsine) was first synthesized in 1904 and rediscovered by Captain W. Lee Lewis in the USA, after whom the agent was named (Vilensky and Redman, 2003). Lewisite was first synthesized in bulk in the US A and, according to Prentiss (1937), the first shipment was on its way to Europe when the 1918 armistice was signed and apparently this shipment was destroyed at sea. Lewisite rapidly acquired a remarkable reputation as the dew of death although there remains no proof of it having been used in war. 

Chlorovinyl arsines chlorovinyl dichloroarsine, dichlorovinyl chloroarsine and trichlorovinyl arsine and mixtures of these qv. It is interesting that several authors refer to the many varieties of lewisite. The chlorovinyl dichloroarsine variant qv is said to be typical. 

Lewisite (a-lewisite or 2-chlorovinyl dichloroarsine) is only slightly soluble in water but when dissolved it hydrolyses rapidly into 2-chlorovinylarsine oxide. The oxide is fairly soluble in sea water. In an alkali solution a further reaction into acetylene and arsenic acid might be possible. With high turbulence, lewisite can dissolve more rapidly in large volumes of water. Because lewisite is 36 per cent arsenic by weight, even if broken down, a toxic element would always remain. 

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