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Overview of Chemical-Warfare Agents


James M. Madsen

, MD, MPH, U.S. Army Medical Research Institute of Chemical Defense (USAMRICD)

Last full review/revision Feb 2021| Content last modified Feb 2021
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Chemical weapons are developed by governments for wartime use and include

  • Toxic agents (intended to cause serious injury or death)

  • Incapacitating agents (intended to cause only temporary, non–life-threatening effects)

  • Incendiary agents (intended to produce light and flame)

Toxic industrial chemicals, as produced for industry, are also capable of causing mass casualties Overview of Incidents Involving Mass-Casualty Weapons Mass-casualty weapons are weapons that can produce a mass-casualty incident. Mass-casualty incidents overwhelm available medical resources because they involve so many injured people (casualties)... read more . Some chemicals (such as chlorine, phosgene, and cyanide compounds) have both industrial and chemical warfare uses.

Toxic agents are divided into four major classes:

Incapacitating agents are divided into

Opioids Opioids Opioids are a class of drugs derived from the opium poppy (including synthetic variations) that are pain relievers with a high potential for misuse. Opioids are used to relieve pain, but they... read more , especially potent fentanyl derivatives such as those reputedly used by Russia against Chechnyan terrorists in 2002, can be considered incapacitating. Although their use is not typically intended to cause serious injury or death, they can easily cause death by stopping breathing when they are used as mass-casualty weapons. In mass-casualty situations, an aerosolized form of opioids will most likely be used. Larger-than-usual doses of naloxone, the rescue drug for opioids, may be needed to reverse the effects of fentanyl derivatives.

In high doses, incapacitating agents can cause serious injury or death.

Incendiary agents, designed to create light and flame, may also cause burns in large numbers of casualties.

In addition to their chemical names and common names, most chemical warfare agents also have a one- to three-letter North Atlantic Treaty Organization (NATO) code. For example, chloroacetophenone is a form of tear gas that is marketed as Mace® and has the code CN.

The views expressed in this article are those of the author and do not reflect the official policy of the Department of Army, Department of Defense, or the US Government.

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