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.
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.
Tabun is an extremely toxic compound of the organophosphate family. It is not present in nature. At room temperature, the pure compound presents itself as a clear and viscous liquid. However, impurities imparted during its manufacture are almost always present in some amount, turning it into a yellow or brown liquid. Exposed to environs, it slowly volatizes into the atmosphere, with the vapor having a slight fruity or almond-like odor. As the compound has a much higher molecular mass compared to air, Tabun gas tends to accumulate in low-lying areas.
Soman is an extremely toxic chemical substance. It is a nerve agent, interfering with normal functioning of the mammalian nervous system by inhibiting the enzyme cholinesterase. It is an inhibitor of both acetylcholinesterase and butyrylcholinesterase. As a chemical weapon, it is classified as a weapon of mass destruction by the United Nations according to UN Resolution 687. Its production is strictly controlled, and stockpiling is outlawed by the Chemical Weapons Convention of 1993 where it is classified as a Schedule 1 substance. Soman was the third of the so-called G-series nerve agents to be discovered along with GA (tabun), GB (sarin), and GF (cyclosarin).
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.
Carbaryl is a chemical in the carbamate family used chiefly as an insecticide. It is a white crystalline solid previously sold under the brand name Sevin, which was a trademark of the Bayer Company. The Sevin trademark has since been acquired by GardenTech, which has eliminated carbaryl from most Sevin formulations. Union Carbide discovered carbaryl and introduced it commercially in 1958. Bayer purchased Aventis CropScience in 2002, a company that included Union Carbide pesticide operations. Carbaryl was the third-most-used insecticide in the United States for home gardens, commercial agriculture, and forestry and rangeland protection. As a veterinary drug, it is known as carbaril (INN).
In organic chemistry, a carbamate is a category of organic compounds with the general formula R2NC(O)OR and structure >N−C(=O)−O−, which are formally derived from carbamic acid. The term includes organic compounds, formally obtained by replacing one or more of the hydrogen atoms by other organic functional groups; as well as salts with the carbamate anion H2NCOO−.
Tetraethylammonium (TEA) is a quaternary ammonium cation with the chemical formula [Et4N]+, consisting of four ethyl groups attached to a central nitrogen atom. It is a counterion used in the research laboratory to prepare lipophilic salts of inorganic anions. It is used similarly to tetrabutylammonium, the difference being that its salts are less lipophilic, more easily crystallized and more toxic.
Ethion (C9H22O4P2S4) is an organophosphate insecticide. It is known to affect the neural enzyme acetylcholinesterase and disrupt its function.
VE is a "V-series" nerve agent closely related to the better-known VX nerve agent. It was first reported in 1958 as a pesticide.
Dimethylamine is an organic compound with the formula (CH3)2NH. This secondary amine is a colorless, flammable gas with an ammonia-like odor. Dimethylamine is commonly encountered commercially as a solution in water at concentrations up to around 40%. An estimated 270,000 tons were produced in 2005.
Diisopropyl fluorophosphate (DFP) or Isoflurophate is an oily, colorless liquid with the chemical formula C6H14FO3P. It is used in medicine and as an organophosphorus insecticide. It is stable, but undergoes hydrolysis when subjected to moisture.
From 1948 to 1975, the U.S. Army Chemical Corps conducted classified human subject research at the Edgewood Arsenal facility in Maryland. These experiments began after the conclusion of World War II, and continued until the public became aware of the experiments, resulting in significant outcry. 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; grouped under the title "Medical Research Volunteer Program" (1956–1975), driven by intelligence requirements and the need for new and more effective interrogation techniques.
Methiocarb is a carbamate pesticide which is used as an insecticide, bird repellent, acaricide and molluscicide since the 1960s. Methiocarb has contact and stomach action on mites and neurotoxic effects on molluscs. Seeds treated with methiocarb also affect birds. Other names for methiocarb are mesurol and mercaptodimethur.
EPN is an insecticide of the phosphonothioate class. It is used against pests such as European corn borer, rice stem borer, bollworm, tobacco budworm, and boll weevil.
A-234 is an organophosphate nerve agent. It was developed in the Soviet Union under the FOLIANT program and is one of the group of compounds referred to as Novichok agents that were revealed by Vil Mirzayanov. In March 2018 the Russian ambassador to the UK, Alexander Yakovenko, claimed to have been informed by British authorities that A-234 had been identified as the agent used in the poisoning of Sergei and Yulia Skripal. Vladimir Uglev, one of the inventors of the Novichok series of compounds, said he was "99 percent sure that it was A-234" in relation to the 2018 Amesbury poisonings, noting its unusually high persistence in the environment.
EA-3990 is a deadly carbamate nerve agent. It is lethal because it inhibits acetylcholinesterase. Inhibition causes an overly high accumulation of acetylcholine between the nerve and muscle cells. This paralyzes the muscles by preventing their relaxation. The paralyzed muscles include the muscles used for breathing.
Octamethylene-bis(5-dimethylcarbamoxyisoquinolinium bromide) (4-673-745-01) is an extremely potent carbamate nerve agent. It works by inhibiting acetylcholinesterase, causing acetylcholine to accumulate. Since the agent molecule is positively charged, it does not cross the blood brain barrier very well.
EA-3966 is a carbamate nerve agent. It is synthesized by reacting 2-dimethylaminomethyl-3-dimethylcarbamoxypyridine with 10-bromodecyltrimethylammonium bromide.
4-686-293-01, also known as Agent 1-10, is a highly potent experimental carbamate nerve agent, patented in May 1967. Due to its high molecular weight and thermal stability, it can remain embedded within various surfaces and clothes for prolonged periods of time. The agent can be decontaminated using bleach or hot caustic soda. The main effector pathway is through the inhibition and antagonization of acetylcholinesterase, achieved by the presence of quaternary ammonium groups in the structure. Perceived as one of the most potent agents in chemical warfare - it can be disseminated through aerosols, explosives or smoke generating munitions.
