HAZMAT Technician Practice Exam

Nerve agents are primarily known to affect the central nervous system. These agents work by disrupting the normal functioning of neurotransmitters, leading to an uncontrolled reaction in the nervous system. Nerve agents inhibit the enzyme acetylcholinesterase, which is responsible for breaking down the neurotransmitter acetylcholine. When this enzyme is inhibited, acetylcholine accumulates, leading to excessive stimulation of nerve cells.

This over-stimulation can manifest as symptoms such as muscle spasms, respiratory failure, convulsions, and ultimately, if not treated promptly, can lead to loss of bodily functions and death. The central nervous system, which includes the brain and spinal cord, is critical in coordinating and regulating most of the body's functions, which is why the primary and most severe effects of nerve agents occur here.

While nerve agents may also impact other systems as a secondary effect—such as causing respiratory distress due to muscle paralysis or affecting heart rate—they fundamentally disrupt the central nervous system's ability to control these functions, demonstrating why they are categorized primarily according to their impact on this system.