Tabun is a colorless, odorless nerve agent that was developed in the 1930s as a pesticide. It is classified as a chemical weapon and is highly toxic, affecting the nervous system by inhibiting the enzyme acetylcholinesterase. This leads to an accumulation of the neurotransmitter acetylcholine, causing muscle spasms, respiratory failure, and potentially death. Due to its dangerous properties, tabun is banned under the Chemical Weapons Convention. It has been stockpiled by various countries and has been used in conflicts, raising concerns about its proliferation and the need for strict international regulations to prevent its use in warfare.