Medical Aspects of Chemical Warfare (2008) - The Black Vault

Decontamination of Chemical CasualtiesabFig. 16-3. (a) Reactive Skin Decontamination Lotion (E-Z-EM Canada Inc, Anjou, Quebec, Canada) packets and (b) bluetraining packets.Photographs: Courtesy Lt Col Charles Boardman, US Air Force, US Army Medical Research Institute of Chemical Defense.The manufacturer (E-Z-EM Inc, Lake Success, NY)also produces a training stimulant (Figure 16-3[b])without oxime, packaged in a blue pouch, that allowsfor realistic training and the incorporation of humandecontamination into civil defense scenarios.Chemical Decontaminants: OxidationElectrophilic reactions are the oxidative processesassociated with CWA detoxification. The most importantcategory of chemical decontamination reactionsis oxidative chlorination. This term covers activechlorine chemicals (such as hypochlorite), whichunder the proper conditions generate the positivelycharged chloride ion, a very reactive electrophile.The pH of a solution is important in determining theamount of active chlorine concentration; an alkalinesolution is advantageous. Hypochlorite solutions actuniversally against the organophosphorus and mustardagents. 1,8Both VX and HD contain sulfur atoms that are readilysubject to oxidation. Current US doctrine specifiesthe use of 0.5% sodium or calcium hypochlorite solutionfor decontamination of skin and a 5% solution forequipment. 1 Decontamination preparations such asfresh hypochlorite solution (either sodium or calciumhypochlorite) react rapidly with some chemical agents(eg, the half-time for destruction of VX by hypochloriteat pH 10 is 1.5 min), but the half-times of destructionof other agents such as mustard are much longer. If alarge amount of agent is initially present, more time isneeded to completely neutralize the agent.Dilute hypochlorite (0.5%) is an effective skin decontaminantfor patient use. The solution should bemade fresh daily with a pH in the alkaline range (pH10–11). Plastic bottles containing 6 ounces of calciumhypochlorite crystals are currently fielded for this purpose.1 Dilute hypochlorite solution is contraindicatedfor the eye; it may cause corneal injuries. It also is notrecommended for brain and spinal cord injuries. Irrigationof the abdomen with hypochlorite solution, whichcan cause adhesions, is also contraindicated. The useof hypochlorite in the thoracic cavity may be less of aproblem, but the hazard remains unknown. 1537