Police across the United States widely used anti-riot agents such as tear gas and OC powder pepper spray to drive away the protesters.
Tear gas was used during the Second World War and is now widely used in riot control as a kind of riot control agent. At present, the anti-riot agents used in hand-held jet self-defense devices at home and abroad mainly include chloroacetophenone (CN), o-chlorobenzylidene malononitrile (CS gas powder), capsaicin (OC), piperine and so on. 2-chlorobenzalmalononitrile (CS, 2-chlorobenzalmalononitrile) has gradually replaced the old tear gas chemical chloroacetophenone due to its low toxicity and strong potency.
OC powder is an oily extract extracted from pepper plants, the main active ingredient of pepper spray. Weapon manufacturers emulsify it in water and propylene glycol, or dissolve it in organic solvents to make pepper spray. The OC powder extract is mainly composed of capsaicin, which is a compound that gives spicy food a spicy taste. The spiciness of OC pepper spray is 2,000,000 spiciness units. In contrast, Sriracha, a hot sauce that is very popular in the United States, has a spiciness of 1000-2500 spiciness units. And there is the OC powder for sale.
When pepper spray is inhaled or absorbed by the mucous membranes of the eyes or nose, the capsaicin and other substances in it will act on the pain receptor TRPV1 in nerve cells. TRPV1 is a cation channel on these nerve cells, which plays an important role in the production and transmission of pain. When capsaicin and other related molecules activate TRPV1, they promote the secretion of pro-inflammatory neuropeptides, and the generated nerve impulses are transmitted to the spinal cord through the central fiber, thereby producing pain. Whether it is powder OC or liquid OC can have such an effect.
The effect of these chemicals is to irritate the mucous membranes of the eyes, nose and throat. They make people cough, sneeze, and make people take off their masks when trying to improve breathing.