lewisite


Also found in: Dictionary, Medical, Acronyms, Wikipedia.
Related to lewisite: British anti lewisite

lewisite

(lo͞o`əsīt'), liquid chemical compound used as a poison gaspoison gas,
any of various gases sometimes used in warfare or riot control because of their poisonous or corrosive nature. These gases may be roughly grouped according to the portal of entry into the body and their physiological effects.
..... Click the link for more information.
. Like mustard gas and nitrogen mustard, it is a blistering agent; when inhaled, it is a powerful respiratory irritant. The absorption of lewisite, which penetrates ordinary clothing and even rubber, through the skin may be fatal. Chemically, lewisite is dichloro-2-chlorovinyl arsine, ClCHCHAsCl2. It boils with decomposition at 190°C;, and its vapor has a faint odor of geraniums. Lewisite is neutralized by reaction with British antilewisite (2, 3-dimercapto-1-propanol). It is named after its developer, the American chemist Winford Lee Lewis.

Lewisite

 

(after the American chemist W. L. Lewis, 1878-1943), ClCH=CHAsCl2, β-dichloro(2-chlorpvinyl) arsine (αlewisite), a war gas with a toxic (systemic), irritating, vesicant effect. The commercial product contains admixtures of bis (β-chlorovinyl) chloroarsine (ClCH = CH)2AsCl (βMewisite) and tris (β-chlorovinyl) arsine (ClCH=CH)3As (γ-lewisite).

A mixture of cis and trans isomers, a-lewisite is characterized by boiling points of 170° and 196°C (melting points, —44 and -1.2°C; density, 1.6092 g/cm3 at 23.5°C). All of these compounds are colorless liquids, insoluble in water but readily soluble in organic solvents.

In water, α-lewisite undergoes rapid hydrolysis to form toxic β-chlorovinylarsenic oxide C1CH—CHAsO. With oxidants (H2O2, HNO3), it is converted to β-chlorovinyl arsenic acid C1CH = CHAsO(OH)2. In the presence of alkalis, a-lewisite readily dissociates to yield acetylene, and c/s-α-lewisite dissociates to yield vinyl chloride.

Lewisite is formed by the reaction of acetylene and AsCl3 in the presence of AlCl3, HgCl2, and other catalysts.

The human body cannot tolerate lewisite concentrations greater than 2.10-2mg per l, which irritate the upper respiratory passages. The lethal doses are 0.25 mg/per l (15 min) when inhaled and 25 mg per kg when absorbed through the skin. Dimercaptopropanol and its derivatives are effective in the treatment of lewisite-induced affections.

Lewisite was first obtained at the end of World War I (1914-18), but it was never used for military purposes.

REFERENCES

Rukovodstvo po toksikologii otravliaiushchikh veshchestv. Kiev, 1964.
Stepanov, A. A. “Otravliaiushchie veshchestva.” Zhurnal Vsesoiuznogo khimicheskogo obshchestva imeni D. I. Mendeleeva, 1968, vol. 13, no. 6.

R. N. STERLIN

lewisite

[′lü·ə‚sīt]
(mineralogy)
(Ca,Fe,Na)2 A titanian romeite mineral.
(organic chemistry)
C2H2 AsCl3 An oily liquid, colorless to brown or violet; forms a toxic gas, used in World War I.
References in periodicals archive ?
Vilensky, author of "Dew of Death: The Story of Lewisite, America's World War I Weapon of Mass Destruction," notes the chemical degrades in the presence of moisture.
Some of the recovered materials tested positive for lewisite and its arsenic containing degradation products.
"The actual and potential existence of surface contamination by lewisite, mustard gas and ordnance is present at levels above which there are assessed to be moderate risks of adverse effects to human health.
Inevitably, Conant stayed on at Harvard, teaching, but when America was dragged into World War I, he agreed to work on the development of a new arsenic-laced combat gas called lewisite. Conant, an Army major, went to work on the topsecret project, which he imagined would make lewisite into "the great American gas which would win the war." He succeeded in mass-producing lewisite in a Cleveland factory, but just as it was being shipped to the European battlefields the war came to an end.
BAL was developed by the British during World War II as an antidote to an arsenical war gas called lewisite, but It was also found to be effective against heavy metals, such as copper.
(3) There were other uses of dedicated CWA agents during declared combat in the 20th century, notably the German bombing of Warsaw in 1939 and the Japanese use of lewisite in China.
to ensure that examination the efficiency of a numerous bio-weapons, officials were understood to have sprayed mustard gas and other skin-burning, lung-ruining chemicals, like Lewisite, on soldiers without their approval or expertise of the experiment occurring to them.
In 2005, it finished disposing of more than 1,143 tons of yperite, lewisite and their mixtures.
Organic arsenic compounds (such arsenobetaine found in mushrooms, fish, and shellfish) generally are less toxic, although organoarsenicals have been used as chemical warfare agents (e.g., lewisite).
And lastly, while geraniums look pleasant in a bed, Beware their smell in wartime - if it's Lewisite - you're dead.
Some authors regard pederin as a natural mimic of vesicating warfare agents such as mustard and Lewisite. (19) When adult beetles are active, a large number of individuals may be affected, which could lead to the false assumption that a chemical agent was used.
Chelation therapy with chelating agents like calcium disodium ethylenediamine tetra acetic acid (Ca[Na.sub.2]EDTA), British Anti Lewisite (BAL), sodium 2,3-dimercaptopropane 1-sulfonate (DMPS), meso 2,3-dimercaptosuccinic acid (DMSA) etc., is considered to be the best known treatment against metal poisoning.