Tear Gas - Effects and Use

Effects and Use

Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes. One of the most probable protein targets is the TRPA1 ion channel that is expressed in sensory nerves (trigeminal nerve) of the eyes, nose and mouth. First used in 1914, xylyl bromide was a popular tearing agent since it was easily brewed.

Lachrymatory agents are commonly used as riot control and chemical warfare agents. During World War I, more toxic lachrymatory agents were used. Certain lachrymatory agents are often used by police to force compliance, most notably tear gas. In some countries (e.g., Finland, Australia, and the United States), another issued substance is mace, which is the same as CN and is used as a personal attack repellent. Xylyl bromide, CN and CS are the oldest of these agents, and CS is the most widely used.

Military use of tear gas (as all other chemical weapons) is prohibited by various international treaties . Police use is not banned in the same manner.