CHAPTER 2: Toxicology of Vesicants

Originally developed as weapons to bypass the rapid advances in respiratory protection, the vesicants are potent contact poisons. The toxicology of two major vesicant agents, sulfur mustard and Lewisite, is reviewed, combining studies originally published in the defence literature with those published in open scientific journals. Vesicants, as liquids or vapours, cause damage to all tissues that they contact. They produce burn like injuries to the skin that manifest as an inflammatory reaction culminating in the formation of the blisters that give them their name. Although the skin injuries are seldom lethal, the damage caused by vesicants to the lungs can produce a fatal pulmonary oedema and long term breathing difficulties. In this chapter, the acute, repeated dose and reproductive system toxicity of sulfur mustard are reviewed together with its toxicokinetics, mutagenic and carcinogenic potential. This toxicology is compared to that available for similar toxic end points for Lewisite. Although originally developed in the early 1900s, the recent use of vesicant chemical warfare agents demonstrates that these chemicals remain agents of concern and a good understanding of the toxicology of these agents is essential.