This document focuses on the exposure, effects, and treatment of nerve agents.
Nerve agents are the most toxic chemical warfare agents known, causing effects within seconds and death within minutes. Though used in only one war, these agents are in the military stockpiles of several countries. They can be manufactured by terrorist groups and have been used in terrorist attacks. Some nerve agents are tabun (GA), sarin (GB), soman (GD), and VX. The effects produced by nerve agent vapor depend on the concentration of vapor. Symptoms include dim vision, "tightness in the chest," and moderate-to-severe impairment of ventilation or gasping for air. The early effects of a drop of nerve agent on the skin depend on the amount of nerve agent, site on the body, the temperature, and the humidity. Effects can be sweating, gastrointestinal symptoms, or fatigue. Nerve agents cause biological effects by inhibiting the enzyme AchE, causing an excess of the neurotransmitter to accumulate. Hyperactivity in those organs innervated by cholinergic nerves results, with increased secretions from exocrine glands, hyperactivity of skeletal muscles leading to fatigue and paralysis, hyperactivity of smooth muscles with bronchoconstriction, and central nervous system changes such as seizure activity and apnea. Behavioral and psychological changes include excessive dreaming, insomnia, and jitteriness, restlessness, increased tension, emotional changes, and fearfulness. Therapy is based on the administration of atropine to minimize the effects of the agent, which may not require complete reversal of all of the effects. Also used in therapy is the oxime 2-PAM C1, which breaks the agent-enzyme bond formed by most agents. Assisted ventilation and other supportive measures are also required in severe poisoning. 160 references