Sarin

Sarin (also called GB) is a colorless, odorless liquid that is extremely potent as a nerve agent. As a result, it is utilized as a chemical weapon by countries and organizations. In fact, sarin is so potent as a nerve agent that it is classified as a weapon of mass destruction.

Sarin was discovered in 1938 in Wuppertal-Elberfeld in Germany by scientists at IG Farben while they were attempting to create stronger pesticides. It was classified as the most toxic of the four G-Series nerve agents made by Germany. The sarin compound was named in honor of the people who discovered it: Schrader, Ambros, Gerhard Ritter, and Van der Linde. It is 26 times more deadly than cyanide.

Effects
Sarin possesses a high volatility that is relative to similar nerve agents. As a result, inhaling it is extremely dangerous and even vapor concentrations may penetrate the skin almost instantly. A person's clothing can release sarin for about a half-hour after it comes in contact with sarin gas, which can lead to exposure of other people. People who absorb a non-lethal dose but do not get immediate treatment may suffer permanent neurological damage.

Even at extremely low concentrations, sarin can be fatal to humans. Death may follow in 1-10 minutes after direct inhalation unless antidotes, typically atropine and pralidoxime, are administered. Atropine is given to treat the physiological symptoms of poisoning (though it cannot counteract the muscular symptoms), while pralidoxime can regenerate cholinesterases if administered within approximately five hours.

Initial symptoms following exposure to sarin are a runny nose, tightness in the chest, and constriction of the pupils. Soon after, there is breathing difficulties, along with nausea and drooling. As the person affected continues to lose control of bodily functions, he or she vomits, defecates, and urinates, quickly followed by twitching and jerking. Ultimately, the victim becomes comatose and is asphyxiated during a series of convulsive spasms.

On Criminal Minds
The unsub of The Witness will use sarin gas in an attack against a Los Angeles city bus.