soman

Soman, commonly designated GD, is a highly toxic organophosphorus nerve agent of the G-series. It was discovered in 1944 by German researchers during wartime chemical weapons research. Soman is a colorless liquid with high potency as a cholinesterase inhibitor, and it is considered one of the most dangerous nerve agents ever developed.

Mechanism and effects: Soman inhibits acetylcholinesterase (AChE) irreversibly, causing an accumulation of acetylcholine at muscarinic and nicotinic receptors throughout the nervous system. This leads to a cholinergic crisis with symptoms such as pinpoint pupils, excessive sweating and secretions, bronchospasm, bronchorrhea, vomiting, diarrhea, muscle fasciculations, weakness, seizures, and potentially fatal respiratory failure. Onset is rapid after inhalation or dermal exposure. The treatment window for effective anticholinergic and reactivating therapies is limited because the AChE–soman complex ages rapidly, reducing the effectiveness of oximes.

Physical properties and persistence: Soman is a volatile, persistent liquid under certain conditions and can contaminate surfaces and equipment. Compared with some other nerve agents, it may demonstrate considerable environmental stability, though hydrolysis and degradation do occur depending on temperature, humidity, and soil or material.

Regulation and history: Soman is a Schedule 1 chemical under the Chemical Weapons Convention, with production, stockpiling, and transfer tightly controlled. Its use is prohibited except for highly restricted research and development. International and national authorities maintain stockpile destruction programs and monitoring to prevent illicit production or deployment.

Medical and safety notes: Immediate decontamination and medical care are essential following exposure. Standard antidotal treatment includes atropine and oximes, with supportive care as needed.