Nerve agents are highly toxic synthetic chemical compounds, primarily recognized as chemical weapons. They severely disrupt the nervous system, making them exceptionally hazardous. Even small amounts can have profound and rapid effects on the human body.
What Nerve Agents Are
Nerve agents are a specific class of organophosphorus compounds, chemicals designed to interfere with the normal functioning of the nervous system. They are man-made and developed for use in chemical warfare, though some related compounds are found in pesticides. These agents are typically liquids at room temperature, with varying evaporation and persistence rates. For example, Sarin (GB) evaporates quickly, while VX is oily and evaporates slowly, persisting longer.
Historical examples include Sarin (GB), Soman (GD), Tabun (GA), and VX. While some nerve agents may have a slight odor, many are odorless or have only a faint smell, meaning odor is not a reliable indicator of their presence. Their classification also depends on volatility and persistence, with “G-series” agents being more volatile and “V-series” agents more persistent.
How Nerve Agents Affect the Body
Nerve agents affect the body by targeting the enzyme acetylcholinesterase (AChE). This enzyme breaks down acetylcholine, a neurotransmitter that transmits signals between nerve cells and to muscles and glands. When AChE is inhibited, acetylcholine rapidly accumulates at nerve endings, leading to continuous overstimulation of muscles and glands throughout the body. This overstimulation results in a “cholinergic crisis,” where the body’s systems become overwhelmed.
Nerve agents can enter the body through several routes, including inhalation of vapor or aerosol, absorption through the skin or eyes, and ingestion. The speed of effects depends on the agent, dose, and exposure route. Inhalation causes symptoms within seconds to minutes, while skin exposure to liquid agents can delay symptoms for minutes to hours, or even up to 18 hours for small amounts.
Recognizing Exposure
Exposure to nerve agents can manifest through a range of signs and symptoms, varying in severity based on the amount of agent absorbed and the route of entry. Initial signs often include pinpoint pupils (miosis), runny nose, watery eyes, and increased salivation and sweating. Individuals might also experience headache, chest tightness, nausea, vomiting, and abdominal pain. These symptoms are due to the overstimulation of muscarinic receptors.
As exposure progresses or if the dose is higher, more severe effects can develop due to the impact on nicotinic receptors and the central nervous system. This can lead to muscle twitching, weakness, and fasciculations (involuntary muscle contractions), potentially progressing to paralysis. Respiratory distress, including bronchospasm and excessive bronchial secretions, can occur. In severe cases, seizures, loss of consciousness, and respiratory failure may follow rapidly.
Immediate Actions After Exposure
If nerve agent exposure is suspected, immediate action is vital to seek medical intervention. The primary step involves removing the affected individual from the contaminated area to prevent further exposure. If clothing is contaminated, it should be removed quickly, preferably by cutting it off to avoid contact with unaffected skin, and then sealed in a plastic bag.
Skin decontamination should be performed promptly by washing thoroughly with large amounts of soap and water. Eyes should be flushed with plenty of water or saline solution.
After initial decontamination, immediate medical attention is necessary, as nerve agent poisoning requires professional treatment. Medical professionals can administer specific antidotes, such as atropine and pralidoxime, which counteract the effects of the nerve agent and help restore normal bodily functions.