Which of the following is a nerve agent example?

• A. Sarin
• B. Mustard gas
• C. Chlorine gas
• D. Hydrogen cyanide

Answer: (A)

Nerve agents disrupt the nervous system by inhibiting acetylcholinesterase, the enzyme that breaks down acetylcholine at synapses. When this enzyme is blocked, acetylcholine builds up, causing excessive stimulation of both muscarinic and nicotinic receptors. That leads to a surge of cholinergic symptoms: severe secretions, bronchoconstriction, slowed heart rate, pinpoint pupils, tremors, seizures, and potentially respiratory failure. Sarin is a classic example because it is an organophosphate nerve agent that rapidly inhibits acetylcholinesterase. In contrast, mustard gas is a vesicant causing blistering, chlorine gas mainly irritates the airways, and hydrogen cyanide blocks cellular respiration. Thus sarin best fits the nerve agent category.