Decontamination arsenic vesicants

Reactive oximes and their salts, such as potassium 2,3-butanedione monoximate found in commercially available Reactive Skin Decontaminant Lotion (RSDL), are extremely effective at rapidly detoxifying arsenic vesicants. 

BAL is the standard treatment for poisoning by arsenic compounds and will alleviate some effects from exposure to arsenic vesicants. It may also decrease the severity of skin and eye lesions if applied topically within minutes after decontamination is complete (i.e., within 2-5 minutes postexposure). Additional chelating agents for the treatment of systemic arsenic toxicity include meso-2,3-dimercaptosuccinic acid (DMSA) and 2,3-dimercapto-l-propanesulfonic acid (DMPS). 

Standard burials are acceptable when contamination levels are low enough to allow bodies to be handled without wearing additional protective equipment. Cremation may be required if remains cannot be completely decontaminated. Although arsenic vesicant agents are destroyed at the operating temperature of a commercial crematorium (i.e., above 1000°F), the initial heating phase may volatilize some of the agents and allow vapors to escape. Additionally, combustion will produce toxic and potentially volatile arsenic oxides. 

Medical Management Immediate decontamination after exposure is the only way to prevent damage to victims, followed by symptomatic management of lesions. Hospital care tends to be supportive. It should be repeated that liquid arsenical vesicants produce more serious lesions on dermal surfaces than do liquid mustard. In toxic victims, liberal fluids by mouth or intravenous, and high-vitamin, high-protein, high-carbohydrate diets could be indicated. For those victims where shock is in evidence, provide the usual supportive measures such as intravenous administration, blood transfusions, or other vascular volume expanders should be indicated. 

Small Areas Decontaminate with copious amounts of full strength household bleach. Removal of porous material, including painted surfaces, that may have absorbed Arsenical Vesicant vapor may be required as these materials could continue to re-release vapor after exposure has ceased. 

It hydrolyses in acidic medium to form HC1 and nonvolatile (solid) chlorovinylarsenious oxide, which is a less potent vesicant than ED. Hydrolysis in alkaline medium, as in decontamination with alcoholic caustic or carbonate solution, produces acetylene and trisodium arsenate (Na3AS04). 

Although the vesicant properties of arsenical agents can be eliminated during decontamination, arsenic is an element and cannot be destroyed. Residual arsenical compounds may still possess significant toxicity if they enter the body through ingestion, or broken, abraded, or lacerated skin (e.g., penetration of skin by debris). 

Similar to the mustard agents, exposure prevention is the first line of defense against lewisite. Rapid decontamination is especially relevant to lewisite exposure due to the rapid development of pain (1-2 min) associated with lewisite exposure. Unlike other vesicants, an effective antidote for lewisite toxicity exists in the form of British anti-lewisite (BAL 2,3-dimercaptopropanol) which binds with arsenicals, thereby countering the lewisite-induced damage. Such chelation therapy is associated with notable side effects (e.g. renal effects) and requires carefiil medical management. More effective analogs of BAL have been developed with less significant side effects. 

Almost 100 years after the first use of mustard gas (HD) in warfare, there is stiU no available antidote, although there is an antidote (British anti-Lewisite) to the vesicant Lewisite, an arsenical compound developed in 1919. Treatment is therefore based on early recognition of the exposure and immediate decontamination to prevent further injury. This is particularly important in the case of the eyes. 

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