February 6 2013 4 06 /02 /February /2013 17:08
Lachrymatory agents, normally called tear gases, are a group of chemicals that cause non-lethal and temporary irritation of the eyes and respiratory passages.
One of the most common tear gases is the often reddish-colored OC (Oleoresin Capsicum), although it is more often called "pepper spray". It is the least toxic and most potent member of the tear gas group, and it has replaced other gases in hand-held spray containers. In those containers, it is good for personal defense and targeting aggressive individuals, but it is not as good for dispersing an unruly crowd. OC does not evaporate or dissolve in water. There is no effective neutralizer. Copious flushing with cold water is the normal decontamination procedure.
My experience with pepper spray
CS gas is what most people think of as tear gas. It is a colorless solid at room temperature that is either placed in solution and dispersed as an aerosol or placed in a pyrotechnic device and dispersed as a smoke. It has very similar effects as pepper spray, and is only mildly toxic. CS can be neutralized by a solution of sodium bisulfite.
Egypt's regime is well known for using tear gas on protestors, with the tear gas being made in the United States. Here is an article by Russia Today about it: http://rt.com/news/egypt-teargas-us-purchase-328/. Here is a picture of the MADE IN USA label. http://a.abcnews.com/images/Blotter/ht_tear_gas_made_usa_110127_wmain.jpg
Here are military servicemembers going through NBC training, in which they breathe in CS gas:
CN is an older tear gas which has pretty much fallen out of use. It is more toxic and less effective then CS. It used to be dissolved in a hydrocarbon solvent and sold as "Mace". Mace now sells "Triple Action Sprays" which contain CN as well as OC.
Here is an article that compares the merits of defense sprays: http://blog.hardtofinditems.com/health-personal-care/mace-vs-pepper-spray-vs-tear-gas-how-to-select-a-personal-defense-spray/
There are several other tear gases that are less commonly used, such as adamsite, a highly toxic arsenic-containing irritant gas developed during World War I, and xylyl bromide. Some new tear gases synthesized from tear-producing onions are also coming into use as a less-toxic alternative to CS and CN.