Mustard Gas (ClCH₂CH₂)₂S

characteristics: pure form is odorless and colorless oily liquid, but the impure agent has the odor of mustard, garlic, horseradish

symptoms of exposure: reddening and blistering of skin, blistering in lining of lungs, burning sensation in eyes

effects: blistering, chronic respiratory impairment, blindness, cancer, death

chemical properties:

source: http://spectrum.troyst.edu/~cking/

molecular formula: (Cl₂CH₂CH₂)₂S

molecular name: 2,2’-dichlorodiethyl sulfide

molecular weight: 159.08 g/mol

melting point: 13˚C

boiling point: 217˚C

density: 1.262 g/cm³ (at 293K)

mechanism:

Mustard gas is actually an oily liquid at room temperature, not a gas. During use, mustard gas would be fit into a shell and the liquid would be dispersed during the explosion into an aerosol.

The chemical mechanism is as follows:

1. nucleophilic attack of carbon by sulfideàintermediate sulfonium salt
2. attack by wateràhemi-mustard HCl
3. attack by waterà thiodiglycol + HCl
4. internal displacementà1,4-thioxane + HCl

The sulfonium ion ring can bind to guanine nitrogen in DNA, thus making it carcinogenic. Furthermore, mustard is lipid soluble, which means that it can be absorped rapidly by the skin.

source: http://www.paulgross.org/tale.html

references:

o http://www.intox.org/databank/documents/chemical/mustardg/mustardg.htm

o http://www.bris.ac.uk/Depts/Chemistry/MOTM/mustard/mustard.htm

o http://en.wikipedia.org/wiki/Mustard_gas

o http://www.rand.org/publications/MR/MR1018.5/MR1018.5.chap3.html