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

Medical Aspects of Chemical WarfareEXHIBIT 16-2DESIRABLE TRAITS OF A SKINDECONTAMINANT• Effective against chemical, biological, radiological,and nuclear agents, toxic industrial material,toxic industrial chemicals, and new threatagents.• Neutralizes all chemical and biologicalagents.• Safe (nontoxic and noncorrosive) for skin,eyes, and wounds.• Removes agent from below the skin surface.• Applied easily by hand.• Readily available.• Acts rapidly over a wide temperaturerange.• Produces no toxic end products.• Stable in long-term storage.• Stable in the short term (after issue to unit /individual).• Affordable.• Does not enhance percutaneous agent absorption.• Nonirritating.• Hypoallergenic.• Disposed of easily.Data sources: (1) Chang M. A Survey and Evaluation of ChemicalWarfare Agent Contaminants and Decontamination. DugwayProving Ground, Utah: Defense Technical InformationCenter; 1984. AD-202525. (2) Baker JA. Paper presented at:COR Decontamination/Contamination Control Master PlanUsers’ Meeting; 11–13 September 1985. (3) Joint RequirementsOffice for Chemical, Biological, Radiological and NuclearDefense. Joint Service Personnel / Skin Decontamination System(JSPDS). Washington, DC: Joint Requirements Office, 2004.found in VX and the G agents. The hydrolysis rateis dependent on the chemical structure and reactionconditions such as pH, temperature, the kind ofsolvent used, and the presence of catalytic reagents.The rate increases sharply at pH values higher than8, and increases by a factor of 4 for every 10°C rise intemperature. 37 Many nucleophilic agents are effectivein detoxifying chemical warfare agents; unfortunately,many of these (eg, sodium hydroxide) are unacceptablydamaging to the skin. Alkaline pH hypochloritehydrolyzes VX and the G agents quite well. 1,38,39The rate of detoxification of HD in water, however,is slow and depends more on the limited solubility ofHD in water (approximately 0.8 g/L at room temperature)than on the reaction rate of hydrolysis (half-lifeat 20°C is 14.7 min). HD is highly soluble in oils andfats. 40 The hydrolysis rate is not affected by pH anddecreases with increasing salt concentration in aqueoussolutions (seawater and saline intravenous bag). Usingstronger nucleophiles such as sulfides and aminesdoes not increase the reaction rate, because the ratedeterminingstep is the initial formation of the cyclicethylene sulfonium ion, which forms directly from theHD molecule. Thus, while nucleophilic detoxificationof HD is possible, oxidative chlorination is much moreeffective, although still slow. 8Liquids are best for decontaminating large or irregularsurface areas. Soapy water solutions are wellsuited for MTFs with adequate water supplies. Soapand water are low-cost materials that remove agentsby hydrolysis and by simply washing them away ifused in copious amounts. These solutions do not killbiological agents or neutralize radiological or chemicalagents; therefore, water run-off must be collected. Liquidsoap acts as a surfactant. The surfactant moleculereduces the water surface tension, making it “wetter”so that it spreads out. Also, one end of the surfactantmolecule is soluble in oily substances, and the otherend is soluble in water. 41,42 This enables water to betterloosen and suspend agent particles in the water so theycan be washed away. Fat-based soaps and emulsifiers/surfactants (eg, Dawn dishwashing liquid [Procter &Gamble, Cincinnati, Ohio], 43 baby shampoo, castileliquid soap, or soft soap) are much more effective thandetergents that dry the skin (the latter should not beused). 44 Soap and water is best used during patientthorough decontamination, but also can be used forimmediate and operational patient decontaminationif available and practical. Copious amounts of soapand water should not be used on the joint service lightweightintegrated suit technology or similar MOPPgarments, because dampening the fabric reduces itsprotective abilities.Dry DecontaminantsAny material that can absorb a liquid and thenbe brushed or scraped off without abrading the skincan be used as an effective skin or equipment decontaminantto remove liquid agents. Clean sand, bakingpowder, fuller’s earth, diatomaceous earth, and babywipes (dry or wet) can be applied to the agent, allowedto absorb it, and then carefully wiped away. Initially,large quantities of thickened liquid agent can be removedfrom clothing and skin by scraping it off withan uncontaminated stick or similar device.Van Hooidonk 45 conducted animal studies todetermine the effectiveness of common householdcompounds for decontamination of liquid agents on534