Nerve agents (also known as nerve gases, though these chemicals are liquid at room temperature) are a class of phosphorus-containing organic chemicals (organophosphates) that disrupt the mechanism by which nerves transfer messages to organs. The disruption is caused by blocking acetylcholinesterase, an enzyme that normally relaxes the activity of acetylcholine, a neurotransmitter. As chemical weapons, they are classified as weapons of mass destruction by the United Nations according to UN Resolution 687, and their production and stockpiling was outlawed by the Chemical Weapons Convention of 1993; the Chemical Weapons Convention officially took effect on April 29, 1997.
Poisoning by a nerve agent leads to contraction of pupils, profuse salivation, convulsions, involuntary urination and defecation, and eventual death by asphyxiation as control is lost over respiratory muscles. Nerve agents can be absorbed through the skin, requiring that those likely to be subjected to such agents wear a full body suit in addition to a respirator.
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