title: Clinical aspects of percutaneous poisoning by the chemical warfare agent VX: effects of application site and decontamination.
abstract: O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothioate (VX) is an extremely toxic organophosphate nerve agent that has been weaponized and stockpiled in a number of different countries, and it has been used in recent terrorist events. It differs from other well-known organophosphate nerve agents in that its primary use is as a contact poison rather than as an inhalation hazard. For this reason, we examined the effects of application site and skin decontamination on VX toxicity in anesthetized domestic swine after topical application. VX applied to the surface of the ear rapidly resulted in signs of toxicity consistent with the development of cholinergic crisis, including apnea and death. VX on the epigastrium resulted in a marked delayed development of toxic signs, reduced toxicity, and reduction in the rate of cholinesterase depression compared with animals exposed on the ear. Skin decontamination (15 minutes post-VX on the ear) arrested the development of clinical signs and prevented further cholinesterase inhibition and death. These results confirm earlier work that demonstrates the importance of exposure site on the resultant toxicity of this agent and they also show that decontamination postexposure has the potential to be an integral and extremely important component of medical countermeasures against this agent.
authors.affiliation: Medical Therapy Group, Chemical Biological Defence Section, Defence Research and Development Canada, Suffield, Box 4000, Medicine Hat, Alberta T1A 8K6, Canada.
authors.forename: Murray G
authors.initials: MG
authors.lastname: Hamilton
authors.forename: Ira
authors.initials: I
authors.lastname: Hill
authors.forename: John
authors.initials: J
authors.lastname: Conley
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Sawyer
authors.forename: Duane C
authors.initials: DC
authors.lastname: Caneva
authors.forename: Paul M
authors.initials: PM
authors.lastname: Lundy
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D001049:Apnea / Q000139:chemically induced; D002619:Chemical Warfare Agents / Q000633:toxicity*; D002802:Cholinesterases / Q000097:blood* / Q000187:drug effects; D003666:Decontamination; D004423:Ear / Q000473:pathology; D006801:Humans; D008297:Male; D023421:Models, Animal; D009946:Organothiophosphorus Compounds / Q000633:toxicity*; D011092:Polyethylene Glycols / Q000008:administration & dosage; D012867:Skin / Q000187:drug effects*; D012869:Skin Absorption / Q000187:drug effects* / Q000502:physiology; D034421:Sus scrofa; D013997:Time Factors; D018675:Toxicity Tests
chemical_list: D002619:Chemical Warfare Agents; D002802:Cholinesterases; D009946:Organothiophosphorus Compounds; D011092:Polyethylene Glycols; C009680:VX-agent