List of chemical warfare agents

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A chemical weapon agent (CWA), or chemical warfare agent, is a chemical substance whose toxic properties are meant to kill, injure or incapacitate human beings. About 70 different chemicals have been used or stockpiled as chemical weapon agents during the 20th century. These agents may be in liquid, gas or solid form.

Contents

In general, chemical weapon agents are organized into several categories (according to the physiological manner in which they affect the human body). They may also be divided by tactical purpose or chemical structure. The names and number of categories may vary slightly from source to source, but, in general, the different types of chemical warfare agents are listed below.

Harassing agents

These are substances that are not intended to kill or injure. They are often referred to as Riot Control Agents (RCAs) and may be used by civilian police forces against criminals and rioters, or in the military for training purposes. These agents also have tactical utility to force combatants out of concealed or covered positions for conventional engagement, and preventing combatants from occupying contaminated terrain or operating weapons. In general, harassing agents are sensory irritants that have fleeting concentration dependent effects that resolve within minutes after removal. Casualty effects are not anticipated to exceed 24-hours nor require medical attention.

Tear agents

These sensory irritants produce immediate pain to the eyes and irritate mucous membranes (aka lachrymatory agent or lachrymator).

Vomiting agents

These sensory irritants are also termed sternators or nose irritants. They irritate the mucous membranes to produce congestion, coughing, sneezing, and eventually nausea.

Malodorants

These are compounds with a very strong and unpleasant smell, which produce powerfully aversive effects without the toxic effects of tear agents or vomiting agents.

Incapacitating agents

These are substances that produce debilitating effects with limited probability of permanent injury or loss of life. The casualty effects typically last over 24 hours, and though medical evacuation and isolation is recommended, it is not required for complete recovery. These, together with harassing agents, are sometimes called nonlethal agents. There may be as high as 5% fatalities with the use of these agents.

Psychological agents

These are substances that produce casualty effects through mental disturbances such as delirium or hallucination.

Other incapacitating agents

These substances have also been investigated as incapacitants, though they operate more through interactions outside the central nervous system.

Lethal agents

These substances are for producing chemical casualties without regard to long-term consequences or loss of life. They cause injuries that require medical treatment.

Blister agents

A blister agent is a chemical compound that irritates and causes injury to the skin. These substances also attack the eyes, or any other tissue they contact.

Vesicants

The vesicants are substances that produce large fluid-filled blisters on the skin.

Nitrogen mustards
  • Bis(2-chloroethyl)ethylamine (HN1)
  • Bis(2-chloroethyl)methylamine (HN2)
  • Tris(2-chloroethyl)amine (HN3)
Sulfur mustards
  • 1,2-Bis(2-chloroethylthio) ethane (Sesquimustard; Q)
  • 1,3-Bis(2-chloroethylthio)-n-propane
  • 1,4-Bis(2-chloroethylthio)-n-butane
  • 1,5-Bis(2-chloroethylthio)-n-pentane
  • 2-Chloroethylchloromethylsulfide
  • Bis(2-chloroethyl) sulfide (Mustard gas; HD)
  • Bis(2-chloroethylthio) methane
  • Bis(2-chloroethylthiomethyl) ether
  • Bis(2-chloroethylthioethyl) ether (O Mustard; T)
Arsenicals

Urticants

The urticants are substances that produce a painful wheal on the skin. These are sometimes termed skin necrotizers and are known as the most painful substances produced.

Blood agents

These substances are metabolic poisons that interfere with the life-sustaining processes of the blood.

Choking agents

These substances are sometime referred to as pulmonary agent or lung irritants and cause injury to the lung-blood barrier resulting in Asphyxia.

Nerve agents

Nerve agents are substances that disrupt the chemical communications through the nervous system. One mechanism of disruption, utilized by the G, GV, and V series of chemicals is caused by blocking the acetylcholinesterase, an enzyme that normally destroys and stops the activity of acetylcholine, a neurotransmitter. Poisoning by these nerve agents leads to an accumulation of acetylcholine at the nerve axon, producing a perpetual excited state in the nerve (e.g. constant muscle contraction). The eventual exhaustion of muscles leads to respiratory failure and death. A separate class of nerve agents are related to Tetrodotoxin, frequently abbreviated as TTX, is a potent neurotoxin with no known antidote. Tetrodotoxin blocks action potentials in nerves by binding to the voltage-gated, fast sodium channels in nerve cell membranes, essentially preventing any affected nerve cells from firing by blocking the channels used in the process.

G series

These are high volatility nerve agents that are typically used for a nonpersistent to semipersistent effect.

GV series

These agents have a volatility between the V and G agents and are typically used for a semi-persistent to persistent effect.

V series

These agents have low volatility and are typically used for a persistent effect or liquid contact hazard.

T series

These agents are related to the puffer fish

Other

Related Research Articles

Nerve agents, sometimes also called nerve gases, are a class of organic chemicals that disrupt the mechanisms by which nerves transfer messages to organs. The disruption is caused by the blocking of acetylcholinesterase (AChE), an enzyme that catalyzes the breakdown of acetylcholine, a neurotransmitter. Nerve agents are irreversible acetylcholinesterase inhibitors used as poison.

<span class="mw-page-title-main">Mustard gas</span> Compound used in chemical warfare

Mustard gas or sulfur mustard is any of several chemical compounds that contain the chemical structure S(CH2CH2Cl)2. In the wider sense, compounds with the substituent S(CH2CH2X)2 and N(CH2CH2X)3 are known as sulfur mustards and nitrogen mustards, respectively, where X = Cl or Br. Such compounds are potent alkylating agents, which can interfere with several biological processes. Also known as mustard agents, this family of compounds are infamous cytotoxins and blister agents with a long history of use as chemical weapons. The name mustard gas is technically incorrect: the substances, when dispersed, are often not gases but a fine mist of liquid droplets. Sulfur mustards are viscous liquids at room temperature and have an odor resembling mustard plants, garlic, or horseradish, hence the name. When pure, they are colorless, but when used in impure forms, such as in warfare, they are usually yellow-brown. Mustard gases form blisters on exposed skin and in the lungs, often resulting in prolonged illness ending in death. The typical mustard gas is the organosulfur compound bis(2-chloroethyl) sulfide.

<span class="mw-page-title-main">Phosgene</span> Toxic gaseous compound (COCl2)

Phosgene is an organic chemical compound with the formula COCl2. It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. It can be thought of chemically as the double acyl chloride analog of carbonic acid, or structurally as formaldehyde with the hydrogen atoms replaced by chlorine atoms. Phosgene is a valued and important industrial building block, especially for the production of precursors of polyurethanes and polycarbonate plastics.

<span class="mw-page-title-main">Chemical warfare</span> Using poison gas or other toxins in war

Chemical warfare (CW) involves using the toxic properties of chemical substances as weapons. This type of warfare is distinct from nuclear warfare, biological warfare and radiological warfare, which together make up CBRN, the military acronym for chemical, biological, radiological, and nuclear, all of which are considered "weapons of mass destruction" (WMDs), a term that contrasts with conventional weapons.

<span class="mw-page-title-main">Sarin</span> Chemical compound and chemical warfare nerve agent

Sarin is an extremely toxic organophosphorus compound. A colourless, odourless liquid, it is used as a chemical weapon due to its extreme potency as a nerve agent. Exposure can be lethal even at very low concentrations, where death can occur within one to ten minutes after direct inhalation of a lethal dose, due to suffocation from respiratory paralysis, unless antidotes are quickly administered. People who absorb a non-lethal dose and do not receive immediate medical treatment may suffer permanent neurological damage.

<span class="mw-page-title-main">Tabun (nerve agent)</span> Chemical compound

Tabun or GA is an extremely toxic synthetic organophosphorus compound. It is a clear, colorless, and tasteless liquid with a faint fruity odor. It is classified as a nerve agent because it can fatally interfere with normal functioning of the mammalian nervous system. Its production is strictly controlled and stockpiling outlawed by the Chemical Weapons Convention of 1993. Tabun is the first of the G-series nerve agents along with GB (sarin), GD (soman) and GF (cyclosarin).

3-Quinuclidinyl benzilate (QNB) is an odorless and bitter-tasting military incapacitating agent. BZ is an antagonist of muscarinic acetylcholine receptors whose structure is the ester of benzilic acid with an alcohol derived from quinuclidine.

<span class="mw-page-title-main">Chemical weapons in World War I</span> Contains Chlorine, phosgene (a choking agent) and mustard gas

The use of toxic chemicals as weapons dates back thousands of years, but the first large-scale use of chemical weapons was during World War I. They were primarily used to demoralize, injure, and kill entrenched defenders, against whom the indiscriminate and generally very slow-moving or static nature of gas clouds would be most effective. The types of weapons employed ranged from disabling chemicals, such as tear gas, to lethal agents like phosgene, chlorine, and mustard gas. This chemical warfare was a major component of the first global war and first total war of the 20th century. The killing capacity of gas was limited, with about 90,000 fatalities from a total of 1.3 million casualties caused by gas attacks. Gas was unlike most other weapons of the period because it was possible to develop countermeasures, such as gas masks. In the later stages of the war, as the use of gas increased, its overall effectiveness diminished. The widespread use of these agents of chemical warfare, and wartime advances in the composition of high explosives, gave rise to an occasionally expressed view of World War I as "the chemist's war" and also the era where weapons of mass destruction were created.

<span class="mw-page-title-main">CS gas</span> Chemical compound

The compound 2-chlorobenzalmalononitrile (also called o-chlorobenzylidene malononitrile; chemical formula: C10H5ClN2), a cyanocarbon, is the defining component of tear gas commonly referred to as CS gas, which is used as a riot control agent.

<span class="mw-page-title-main">VX (nerve agent)</span> Chemical compound and chemical warfare nerve agent

VX is an extremely toxic synthetic chemical compound in the organophosphorus class, specifically, a thiophosphonate. In the class of nerve agents, it was developed for military use in chemical warfare after translation of earlier discoveries of organophosphate toxicity in pesticide research. In its pure form, VX is an oily, relatively non-volatile liquid that is amber-like in colour. Because of its low volatility, VX persists in environments where it is dispersed.

<span class="mw-page-title-main">Blister agent</span> Chemicals that result in blistering and skin irritation and damaging

A blister agent, is a chemical compound that causes severe skin, eye and mucosal pain and irritation. They are named for their ability to cause severe chemical burns, resulting in painful water blisters on the bodies of those affected. Although the term is often used in connection with large-scale burns caused by chemical spills or chemical warfare agents, some naturally occurring substances such as cantharidin are also blister-producing agents (vesicants). Furanocoumarin, another naturally occurring substance, causes vesicant-like effects indirectly, for example, by increasing skin photosensitivity greatly. Vesicants have medical uses including wart removal but can be dangerous if even small amounts are ingested.

<span class="mw-page-title-main">Chemical burn</span> Medical condition

A chemical burn occurs when living tissue is exposed to a corrosive substance or a cytotoxic agent. Chemical burns follow standard burn classification and may cause extensive tissue damage. The main types of irritant and/or corrosive products are: acids, bases, oxidizers / reducing agents, solvents, and alkylants. Additionally, chemical burns can be caused by biological toxins and by some types of cytotoxic chemical weapons, e.g., vesicants such as mustard gas and Lewisite, or urticants such as phosgene oxime.

<span class="mw-page-title-main">Chlormethine</span> Chemical compound

Chlormethine, also known as mechlorethamine, mustine, HN2, and embikhin (эмбихин), is a nitrogen mustard sold under the brand name Mustargen among others. It is the prototype of alkylating agents, a group of anticancer chemotherapeutic drugs. It works by binding to DNA, crosslinking two strands and preventing cell duplication. It binds to the N7 nitrogen on the DNA base guanine. As the chemical is a blister agent, its use is strongly restricted within the Chemical Weapons Convention where it is classified as a Schedule 1 substance.

Phosgene oxime, or CX, is an organic compound with the formula Cl2CNOH. It is a potent chemical weapon, specifically a nettle agent, which is a type of blister agent. The compound itself is a colorless solid, but impure samples are often yellowish liquids. It has a strong, disagreeable and irritating odor. It is used as a reagent in organic chemistry.

Benzyl chloride, or α-chlorotoluene, is an organic compound with the formula C6H5CH2Cl. This colorless liquid is a reactive organochlorine compound that is a widely used chemical building block.

This is the list of extremely hazardous substances defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act. The list can be found as an appendix to 40 CFR 355. Updates as of 2006 can be seen on the Federal Register, 71 FR 47121.

<span class="mw-page-title-main">Edgewood Arsenal human experiments</span> US military chemical warfare research

From 1948 to 1975, the U.S. Army Chemical Corps conducted classified human subject research at the Edgewood Arsenal facility in Maryland. The purpose was to evaluate the impact of low-dose chemical warfare agents on military personnel and to test protective clothing, pharmaceuticals, and vaccines. A small portion of these studies were directed at psychochemical warfare and grouped under the prosaic title of the "Medical Research Volunteer Program" (1956–1975). The MRVP was also driven by intelligence requirements and the need for new and more effective interrogation techniques.

Acute inhalation injury may result from frequent and widespread use of household cleaning agents and industrial gases. The airways and lungs receive continuous first-pass exposure to non-toxic and irritant or toxic gases via inhalation. Irritant gases are those that, on inhalation, dissolve in the water of the respiratory tract mucosa and provoke an inflammatory response, usually from the release of acidic or alkaline radicals. Smoke, chlorine, phosgene, sulfur dioxide, hydrogen chloride, hydrogen sulfide, nitrogen dioxide, ozone, and ammonia are common irritants.

<span class="mw-page-title-main">Bis(2-chloroethyl)sulfide</span> Chemical compound formerly used in warfare

Bis(2-chloroethyl)sulfide is the organosulfur compound with the formula (ClCH2CH2)2S. It is a prominent member of a family of cytotoxic and blister agents known as mustard agents. Sometimes referred to as mustard gas, the term is technically incorrect: bis(2-chloroethyl)sulfide is a liquid at room temperature. In warfare it was dispersed in the form of a fine mist of liquid droplets.

References

  1. Chemical Warfare Bulletin. Vol 12. p 312.
  2. Chris Trueman. "Poison Gas and World war One". History Learning Site. Retrieved 2010-08-26.