IN THE LATE 1960s, a Pennsylvania man named Alan Litman fretted that his wife wouldn’t be safe coming home late on the mean streets of Pittsburgh. So he did what any doting husband would do—he figured out a way to fill a portable, easily deployed spray can with tear gas. Then he started marketing the product to law enforcement. Today his invention is known as Mace, a brand now synonymous with private citizens packing a ton of heat. The company’s triple-action variety is a one-two punch of painful riot-control agents—pepper spray and tear gas, which have been used for decades to subdue and incapacitate people without killing them—plus UV dye to make targets readily identifiable post-melee.
The first active ingredient, CN for short, is this early type of tear gas. White, powdery CN reacts with enzymes and other molecules on your body, triggering pain and irritation. It also stimulates TRPA1—the receptor that sends pain signals to your brain when you eat wasabi. The result? Your body overflows with tears, snot, and saliva as it attempts to get the CN off. Oh, and it smells like delightful apple blossoms.
Extracted from dried chili peppers, this oily goop is riddled with molecules that bind to the receptor TRPV1, which alerts you if, say, your hand is on fire. One spritz is a kajillion times more burny than eating a habañero, turning your face into a searing world of hurt.
The formula’s third “action” item is a UV dye, which renders sprayees readily identifiable by making them glow under a black light. Mace is coy about which chemicals it uses, but likely suspects include compounds called stilbenes. They’re optical brighteners, which absorb UV light and reflect blue and purple tinges; laundry detergents often contain them to make yellowed clothing look whiter and thus cleaner.
Dipropylene Glycol Monomethyl Ether
This organic solvent ensures that chloroacetophenone and oleoresin capsicum don’t clump up and fail to deploy.
Another solvent, derived from the oil in orange peels. A fragrant molecule called a terpene, it’s so good at dissolving things that it’s used for tough tasks like removing graffiti and degreasing engines. It also breaks down the neoprene rubber that keeps the Mace sealed in the container, which is why it’s tempered with mellower dipropylene glycol monomethyl ether. D-limonene is also an irritant, familiar to anyone who’s been squirted in the eye by an orange they were peeling.
Compressed and squeezed into the canister, nitrogen gas is the propellant. When you push the button, the nitrogen shoves the pungent, debilitating cocktail along the path of least resistance: up a tube and out onto your soon-to-be-miserable assailant.
source: wired.com by CHELSEA LEU