Tear Gas and Pepper Spray Toxicity

Tear gas and pepper spray are a group of heterogeneous agents known under broader categories as riot control agents, harassing agents, incapacitating agents, or lacrimators. Although initially utilized by the military in World War I, they are now used for personal protection or by law enforcement agencies as a non-lethal option for subduing combative subjects as well as crowd control. As a group, these substances cause acute eye pain, tearing, skin irritation, and respiratory tract irritation.  The prototypical tear gasses are o-chlorobenzylidenemalononitrile (CS), chloroacetophenone (CN), and dibenzoxazepine (CR). CN was initially developed at the end of the first world war, although it did not get used during combat. After this time, CN was primarily utilized by military and law enforcement agencies until the development of CS, which is more potent and less toxic. CS, named for its creators Corson and Stoughton, was first developed in 1928 and first used in 1958 by the British army. CS was an attractive agent for law enforcement because it was more effective in the open air. It has mostly replaced CN by law enforcement agencies. Pepper spray was created in the late 1970s and found use by law enforcement agencies in the early 1980s. Oleoresin capsicum (OC) is the active agent in pepper spray, which is an oily concentrated extract from plants of the genus , more commonly referred to as the chili pepper. The physiologic and pharmacologic effects of capsaicin have been a topic of study since the 1920s. More recently it has found favor as a riot-control agent with law enforcement agencies. It produces some similar effects compared to the other tear gases and has become the popular agent for civilian use.