Not exactly a poison, Adamsite is used as a riot control agent, as a *super tear gas* and vomit-inducing agent that causes the victim to begin uncontrollable projectile vomiting. While it can be lethal in large enough quantities, as in enclosed rooms, when the target begins throwing up pieces of small intestine and blood, it's real value is in forcing the removal of protective gas masks, and so is commonly mixed with other agents, particularly tear gas. Chemically known as diphenylaminochloroarsine, it's blessedly known as agent DM in US use, most usually packaged as the M6 or M6A1 CN-DM riot control hand grenade.
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