Sulfur mustard (SM) or mustard gas [bis(2-chloroethyl)sulphide; CASRN: 505-60-2] was first synthesized by Despretz in 1822, and was rediscovered later by Guthrie and Niemann.^1,2  The latter researchers noted the typical vesicant properties of SM and there is some evidence that Niemann suffered from pulmonary late effects resulting in an early death.

Meyer synthesized SM of higher purity, which was an important step towards the production of large quantities of this compound.³  SM toxicity and its easy synthesis were the main reasons why the German chemists Lommel and Steinkopf made the decision to use this substance as a chemical warfare agent. Although SM was first used in the last year of World War I (WWI), it achieved the title “king of chemical warfare agents”. The mortality of SM is comparatively low, but the burden to the medical system is high. Many victims need long lasting medical care after exposure. After the Iraq–Iran war (1980–1988), nearly 30 000 Iranian victims still suffer from late effects.