CS Gas

CS Gas Chemical formula

Chemical information

CS Gazi; CS Spray; Gas CS.
Chemical formula: C10H5ClN2 = 188.6.
CAS — 2698-41-1.


CS gas (more properly CS spray) is the name commonly given to a particulate dispersion of α-(o-chlorobenzylidene) malonitrile, used as a riot-control agent or ‘tear gas’. Its toxic effects include irritation of the eyes and nose, with copious lachrymation and rhinorrhoea; blepharospasm; a burning sensation of the mouth and throat; tightness in the chest, with difficulty in breathing; coughing; an increase in salivation; and retching and vomiting. These effects usually disappear within 15 minutes after exposure ends. The effects of pre-existing disease of the respiratory tract may be exacerbated. Erythema and blistering of the skin may occur. If symptoms persist, the patient should be removed to a well ventilated area. Treatment is symptomatic. Contaminated skin may be washed with soap and water, but only if symptoms persist since exposure to water may initially exacerbate symptoms. If contamination of the eyes has been severe they should be irrigated with physiological saline or water.
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Published May 08, 2019.