Organic arsenicals lewisite

Dimercaprol (BAL, British Anti-Lewisite) was developed in World War 11 as an antidote against vesicant organic arsenicals (B). It is able to chelate various metal ions. Dimercaprol forms a liquid, rapidly decomposing substance that is given intramuscularly in an oily vehicle. A related compound, both in terms of structure and activity, is di-mercaptopropanesulfonic acid, whose sodium salt is suitable for oral administration. Shivering, fever, and skin reactions are potential adverse effects. 

Lewisite [dichloro(2-chlorovinyl)arsine] is an organic arsenical known for its vesicant properties (Rosenblatt et al., 1975). It has a molecular weight of 207.32, vapor pressure of 0.58 mm HG at 25°C, a liquid density of 1,89 g/cm at 25°C, freezing point of -18°C, boiling point of 190°C, and is negligibly soluble in water (DA, 1974). The chemical structure of lewisite is shown below. Lewisite may occur as a trans-isomer and as a cis-isomer. In aqueous solutions, the cis-isomer undergoes photoconversion to the trans-isomer (Clark, 1989). hi the presence of moisture, lewisite is rapidly converted to the more stable but highly toxic lewisite oxide (2-chlorovinylarsenous acid) (Cameron et al., 1946). 

Potentiometric titration and colorimetric methods have been described for the determination of )5-chlorovinyldichloroarsine (Lewisite) . In the latter the organic arsenic is mineralized by refluxing with aqueous sodium hydrogen carbonate and then oxidized to... 

Other organic arsenical chemical warfare agents are methyldichlorarsine (MD), phenyldichloroarsine (PD), and ethyldichloroarsine (ED). These plus lewisite (L), mustard agents, and phosgene oxime make up the vesicant class. 

Treatment of inorganic arsenic poisoning involves decontamination procedures and use of the antidote BAL (British anti-lewisite compound 2,3-dime-rcaptopropanol). Use of demulcent to coat the gastrointestinal tract and the use of antibiotics is also recommended. Organic arsenic poisoning treatment involves only withdrawal of the feed involved, with recovery occurring in 3-5 days. Severely affected pigs should be culled. 

Use Antidote to Lewisite, organic arsenicals, and heavy metals. 

Blister agents Also known as vesicants, these are chemical weapon compounds that cause severe blistering of the skin, as well as damage to the eyes, mucous membranes, respiratory tract and internal organs. This class of chemical weapon agent includes the arsenicals/Lewisites (L), phosgene oxime (CX), and sulfur mustards (HD, HN). 

Lewisite (L). Colorimetric tubes are available which can detect organic arsenic compounds as well as arsine. Detection with PIDs or FIDs may be possible. Detection and identification with FT-IR is possible provided that the appropriate reference spectra are available. 

Liquids Some, but not all components of Sulfur/Arsenical Vesicants can be detected by M8 paper. All components of Sulfur/Arsenical Vesicants can be detected by M9 papers. The APD 2000 provides semi-quantitative identification of sulfur mustard/Lewisite mixtures. Colorimetric tubes are available which can detect thioethers, organic arsenic compounds as well as arsine (AsHg). Detection with PIDs or PIDs may be possible. Detection and identification with FT-IR is possible provided that the appropriate reference spectra are available. 

B. The detection of lewisite is facilitated by the fact that it forms colored products with many reagents. Draeger tubes are available which react with organic arsenicals. However, no automatic detectors are available for use in the field. 

Organic arsenical L (lewisite) Nerve agents GA (tabun)... 

The found high concentrations of arsenic may be caused both by inorganic and organic arsenous compounds and a-lewisite or its hydrolysis product P-chlorovinylarsineoxide in particular. 

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