The Chemical Weapons Convention 1993, of which the US is a signatory, bans the use of tear gas in warfare. Yet something considered too cruel and unusual for the battlefield has been used multiple times in recent years on crowds in America.
Some scientists and international observers contend the tactic of spraying people with tear gas, which commonly uses the chemical agent 2-chlorobenzalmalononitrile (CS), can pose serious dangers.
Sven-Eric Jordt, a nerve gas expert at Yale University School of Medicine, explained, “Tear gases are nerve gases that specifically activate pain-sensing nerves.”
“The use of tear gas in … situations of civil unrest, however, demonstrates that exposure to the weapon is difficult to control and indiscriminate, and the weapon is often not used correctly,” wrote Howard Hu in the Journal of the American Medical Association in 1989. Hu found that if exposed to “high levels of CS,” some victims experienced heart failure or even death.