Mustard agents reactivity

Once chemical agents are fully dispersed, they do not tend to persist in the environment because of their high chemical reactivity, particularly with water (hydrolysis). However, in extremely dry desert climates, they can persist for considerable periods of time (U.S. Army, 1988). The major environmental degradation products of nerve and mustard agents have recently been assessed and their persistence and toxicity evaluated. A potential hydrolysis product of VX (S-(2-diisopropylaminoethyl) methylphosphonothioic acid [EA-2192]) is a degradation product expected to display a high level of mammalian toxicity. Some mustard partial hydrolysis products are also toxic (Munro et al., 1999). 

An antidote is available for lewisite exposure. BAL (British-Anti-Lewisite dimercaprol) was developed by the British during World War II. The antidote is produced in oil diluent for intramuscular administration to counter the systemic effects of lewisite. There is no effect, however, on the skin lesions (eyes, skin, and respiratory system) from the antidote. Mustard agents (H), (HD), (HS), and (HT), like nerve agents, would be classihed as Class 6.1 poisons by the DOT and would have NFPA 704 designations of health 4, flammability 1, reactivity 1, and special... 

Results from a study using live mustard agent showed that the dry wipe was able to adsorb the off-gassing mustard vapors better than the particulate activated carbon and M291 reactive adsorbent substrate. In addition, this wipe performed better in its material compatibility characteristics with strong acids and bases. Another study has proven that the dry decontamination wipe is capable of adsorbing vapors from organophosphorus compoimds like methyl parathion. " ... 

The adventitious discovery of the antitumor action of the nitrogen mustard poison war gases led to intensive investigation of the mode of action of these compounds. In brief, it has been fairly well established that these agents owe their effect to the presence of the highly reactive bis(2-chloroethyl)amine group. The cytotoxic activity of... 

Very reactive nitrogen mustards and aziridine-containing molecules are usually too toxic for general therapeutic use, but find use in neoplastic disease. Benzodepa (182) is such an agent. Treatment of ethyl carbamate with phosphorous pentachloride leads to cyanate 180 which readily adds benzyl alcohol to produce carbamate 181. Displacement of the active... 

Rapid advances in chemistry during the nineteenth and twentieth centuries, coupled with the success of mustard gas as a toxic weapon in World War I, attracted attention to the warfare potential of chemical agents. This led to support for research on lethal nerve agents during and immediately after World War II. The research was followed by the development of treatment methods, and prominent among these was the use of cholinesterase reactivators to reverse the lethal effects of anticholinesterase nerve gases. 

Cyclophosphamide (72) was made as a latent form of nitrogen mustard with fairly low toxicity. It undergoes oxidation by microsomes in the liver and then breaks down to give much more reactive derivatives of 2,2 -dichlorodiethylamine (Scheme 3). Several aziridines are used as alkylating agents. They include triethylenemelamine (73), triaziquone (74), TEPA (triethylenephosphoramide) (75 X = O) and thio-TEPA (75 X = S). Ethylene oxide... 

Among the most biologically reactive alkylating agents are the nitrogen and sulfur "mustards" such as bis-(2-chloroethyl)sulfide. These toxic bifunctional compounds cause lethal crosslinking of DNA chains... 

The sulfur mustards gave rise to the nitrogen mustards, which are less reactive alkylating agents that are used as anticancer drugs. Nitrogen mustards alkylate DNA, which prevents its reproduction and ultimately kills the cells. 

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