What Tear Gas Is and How It Works

Tear gas, or lachrymatory agent, refers to any of a number of chemical compounds that cause tears and pain in the eyes and sometimes temporary blindness. Tear gas can be used for self-defense, but it is more commonly used as a riot control agent and as a chemical weapon. How Tear Gas Works Tear gas irritates the mucous membranes of the eyes, nose, mouth, and lungs. The irritation may be caused by a chemical reaction with the sulfhydryl group of enzymes, though other mechanisms also occur. The results of exposure are coughing, sneezing, and tearing. Tear gas generally is non-lethal, but some agents are toxic. Examples of Tear Gas Actually, tear gas agents arent usually gases. Most compounds used as lachrymatory agents are solids at room temperature. They are suspended in solution and sprayed as aerosols or in grenades. There are different types of compounds that may be used as tear gas, but they often share the structural element ZC-C-X, where Z denotes carbon or oxygen and X is bromide or chloride. CS (chlorobenzylidenemalononitrile)CRCN (chloroacetophenone) which may be sold as Macebromoacetonephenacyl bromidexylyl bromidepepper spray (derived from chili peppers and most commonly dissolved in a vegetable oil) Pepper spray is a little different from the other types of tear gas. It is an inflammatory agent that causes inflammation and burning of the eyes, nose, and mouth. While it is more debilitating than a lachrymatory agent, it is harder to deliver, so it is used more for personal protection against a single individual or animal than for crowd control. Sources Feigenbaum, A. (2016). Tear Gas: From the Battlefields of WWI to the Streets of Today. New York and London: Verso. ISBN 978-1-784-78026-5.Rothenberg, C.; Achanta, S.; Svendsen, E.R.; Jordt, S.E. (August 2016). Tear gas: an epidemiological and mechanistic reassessment. Annals of the New York Academy of Sciences. 1378 (1): 96–107.  doi:10.1111/nyas.13141Schep, L.J.; Slaughter, R.J.; McBride, D.I. (June 2015). Riot control agents: the tear gases CN, CS and OC-a medical review. Journal of the Royal Army Medical Corps. 161 (2): 94–9. doi:10.1136/jramc-2013-000165