When things get rough in a crowd or a demonstration, or when altercations occur in high tension situations, the best non-lethal way to defuse the chaos would be to use tear gas. But what exactly does tear gas do that makes it effective?
Before the tearing, the choking and the pouring mucus, tear gas burns. It causes searing pain in the eyes, skin, lungs and mouth—or anywhere it touches. “It can be overwhelming and incapacitating. You can be forced to shut your eyes and cannot open them,” says Sven-Eric Jordt, an anesthesiologist at Duke University. And then comes the coughing and the nausea and the vomiting.
“I think of tear gas as a pain gas,” he says. “Because it directly activates pain-sensing receptors.” Weapons like sarin gas cause muscle paralysis that can lead to suffocation. These are designed to kill, while tear gas’ purpose is to repel crowds through maximum misery.
Read more about the chemical components of tear gas in an article by Angus Chen on Scientific American.
(Image credit: Wikimedia Commons)