Lewisite other effects

One such decontaminant is supertropical bleach (STB). STB is a mixture of chlorinated lime and calcium oxide containing about 30% available chlorine. It can be used either as a dry mix or as a slurry to decontaminate some equipment surfaces and terrain. The dry mix is prepared with two parts bleach to three parts earth by volume. A slurry typically consists of 40 parts STB to 60 parts by weight of water. This material is then sprayed or swabbed on the contaminated surface (see Bleaching agents). STB is an effective decontaminant for mustard, lewisite, and VX. It is less effective against nerve agents other than VX. 

Liquid lewisite applied by eye-dropper to the forearms of men caused blanching and discoloration of the skin followed by extensive erythema within 15 to 30 minutes and vesication within 12 hours or less (Wardell, 1941, as cited in Goldman and Dacre, 1989). The pain associated with these dermal exposures reportedly occurred within two minutes and considerable discomfort persisted for about one week. Other tests with human subjects and clinical reports also indicate a similar temporal sequence of events. Exposure to lewisite vapor (0.06 to 0.33 mg/L) caused discoloration and blistering with the maximum effect occurring by 36 to 48 hours after exposure (Wardell, 1941). At a concentration of 0.01 mg/L, lewisite vapor caused inflammation of the eyes and swelling of the eyelids after 15 minutes of exposure, and inhalation of 0.5 mg/L for five minutes is considered to be potentially lethal. 

Human data regarding reproductive/developmental effects due to lewisite exposure are inconclusive because of confounding factors such as concurrent exposure to other agents such as sulfur mustards and incomplete exposure data. Yamakido et al. (1985) studied workers from the Okuno-jima (Japan) factory where mustard and lewisite were manufactured in the World War II era, and noted no evidence of agent-induced mutations. 

Copper toxicity has been observed, althongh it is not a function of dietary overload. Abnormally low levels of ceruloplasmin associated with the genetic disorder, Wilson s disease, lead to excessive deposition of copper in the central nervous system, ocular tissue, liver, and other organs. Severe psychotic symptoms are observed. Urinary excretion of the copper can be achieved with specific chelating agents such as British anti-lewisite (BAL, 2,3-dimercaptopropanol) or penicillamine, orally administered. Symptoms of the disease are reversed as the copper levels return to normal. Reduction of dietary copper nptake by competition with relatively high levels of oral zinc is also effective. ... 

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. 

In acute exposure prompt medical attention is critical. The victim should be immediately removed to fresh air and away from the source of exposure. Oxygen should be provided if there is a respiratory distress. Initial therapy should be directed at stopping the ongoing hemolysis by performing exchange transfusion. Currently there is no other treatment to decrease arsine hemolysis however, studies in vitro have shown that some dithiol chelators (meso-2,3-dimercaptosuccinic acid, DMSA 2,3-dimercapto-l-propanesulfonic acid, DMPS and 2,3-butanedithiol) are effective (see Further Reading). This should be followed by aims to restore renal function or compensate for lost renal function (hemodialysis). This process does not remove any formed arsenic from the exposed body. Administration of dimercaprol (British Anti-Lewisite, BAL) has no effect on arsine hemolysis, but it lowers blood arsenic levels resulting from arsine exposure. The use of chelators must be... 

Little is known about lewisite s stability in the environment, but it can react with water in a manner whereby its volatility and most of its blistering potency are lost. As a potent blister agent, it has irritant effects on the eyes and respiratory system, and has similar toxicities to the other blister agents mentioned above (except that it exhibits less bone marrow suppression). Similar to its dichloroarsine cousins and phosgene oxime, but unlike the mustard vesicants, it can cause pain at the time of initial contact. There is often no erythema around the vesicles as with other mustard agents. 

Research on anesthetic gases during the nineteenth century facilitated the development and use of poisonous war gases in the twentieth. This led to attempts to counteract the effects of chemical warfare agents and other toxic compounds, particularly arsenicals, introduced by Paul Ehrlich (1854-1915) for the treatment of syphilis. This resulted in the synthesis of the first specific chemical antidote, British anti-Lewisite (BAL), in 1945 by R.A. Peters, L.A. Stocken, and R.H.S. Thompson in Oxford. Studies on the mechanistic bases for toxicity were applied to the synthesis of effective insecticides. For example, during the 1940s, the Swiss chemist Paul Muller discovered a compound, now known as DDT, that poisons insects on contact. 

After sulfur and nitrogen mustards are absorbed and interact with body tissues, they are no longer intact molecules. Therefore, unlike nerve gas victims, the body fluids of decontaminated mustard-exposed patients pose no risk to health care providers or other responders (2). In contrast to the other vesicants, Lewisite does not require a cyclization reaction, so its effects are immediate. Through direct inhibition of thiol-containing enzymes. Lewisite disrupts energy pathways, causing ATP depletion, cell death, and clinical effects (15). 

Management of Lewisite or Mustard-Lewisite exposure is similar to that of nitrogen and sulfur mustard exposures with two exceptions. First, patients exposed to Lewisite or the mixture will have an abrupt onset of symptoms and will likely present to emergency rooms immediately after exposure. On the other hand, because of the delayed effects, most patients with severe exposures to nitrogen or sulfur mustards will go home or elsewhere after their exposure and may only present later at emergency rooms or physicians offices when they begin developing symptoms. 

Lewisite. British anti-lewisite is also effective against other heavy metals, such as gold, excessive copper deposition seen in Wilson s disease (El-Youssef, 2003), and mercury (Goldman and Dacre, 1989). Newer analogs of BAL have been synthesized to improve efficacy, such as DMSA, 2,3-dimer-capto-1-propane sulfonic acid, and A-(2,3 dimercaptopropyl-phthalamidic acid) (DMPA). 

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