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 acetylcholinesterase inhibitors used as poison.
The Organisation for the Prohibition of Chemical Weapons (OPCW) is an intergovernmental organisation and the implementing body for the Chemical Weapons Convention (CWC), which entered into force on 29 April 1997. The OPCW, with its 193 member states, has its seat in The Hague, Netherlands; it oversees the global endeavour for the permanent and verifiable elimination of chemical weapons.
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 fatally interferes 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).
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 recent years, VX was found to be the agent used in the assassination of Kim Jong-nam. 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.
The Russian Federation is known to possess or have possessed three types of weapons of mass destruction: nuclear weapons, biological weapons, and chemical weapons. It is one of the five nuclear-weapon states recognized under the Treaty on the Non-Proliferation of Nuclear Weapons.
Novichok is a group of nerve agents, some of which are binary chemical weapons. The agents were developed at the GosNIIOKhT state chemical research institute by the Soviet Union and Russia between 1971 and 1993. Some Novichok agents are solids at standard temperature and pressure, while others are liquids. Dispersal of solid form agents is thought possible if in ultrafine powder state.
VR is a "V-series" unitary nerve agent closely related to the better-known VX nerve agent. It became a prototype for the series of Novichok agents. According to chemical weapons expert Jonathan Tucker, the first binary formulation developed under the Soviet Foliant program was used to make Substance 33, differing from VX only in the alkyl substituents on its nitrogen and oxygen atoms. "This weapon was given the code name Novichok."
Cholinesterase inhibitors (ChEIs), also known as anti-cholinesterase, are chemicals that prevent the breakdown of the neurotransmitter acetylcholine or butyrylcholine. This increases the amount of the acetylcholine or butyrylcholine in the synaptic cleft that can bind to muscarinic receptors, nicotinic receptors and others. This group of inhibitors is divided into two subgroups, acetylcholinesterase inhibitors (AChEIs) and butyrylcholinesterase inhibitors (BChEIs).
EA-3148 is a "V-series" nerve agent related to the better-known compounds VX and VR. It was studied by both the US and Soviet chemical weapons programmes during the Cold War, and is notable as the only V-series organophosphate nerve agent specifically identified in public domain sources as having a higher absolute potency as an acetylcholinesterase inhibitor than VX. However, both the US and Soviet investigations of the compound concluded that despite its high potency, the physicochemical properties of the substance made it unsuitable for weaponisation, and further research was not conducted.
Vil Sultanovich Mirzayanov is a Russian chemist of ethnic Tatar origin who now lives in the United States, best known for revealing secret chemical weapons experimentation in Russia.
On 4 March 2018, Sergei Skripal, a former Russian military officer and double agent for the British intelligence agencies, and his daughter, Yulia Skripal, were poisoned in the city of Salisbury, England. According to UK sources and the Organisation for the Prohibition of Chemical Weapons (OPCW), they were poisoned by means of a Novichok nerve agent. Both Sergei and Yulia Skripal spent several weeks in hospital in a critical condition, before being discharged. A police officer, Nick Bailey, was also taken into intensive care after attending the incident, and was later discharged.
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.
Chemical weapons have been a part of warfare in most societies, although their use has been particularly controversial since the 20th century.
On 20 August 2020, Russian opposition figure and anti-corruption activist Alexei Navalny was poisoned with a Novichok nerve agent and was hospitalized in serious condition. During a flight from Tomsk to Moscow, he became ill and was taken to a hospital in Omsk after an emergency landing there, and put in a coma. He was evacuated to the Charité hospital in Berlin, Germany, two days later. The use of the nerve agent was confirmed by five Organisation for the Prohibition of Chemical Weapons (OPCW) certified laboratories. On 7 September, doctors announced that they had taken Navalny out of the induced coma and that his condition had improved. He was discharged from the hospital on 22 September 2020. The OPCW said that a cholinesterase inhibitor from the Novichok group was found in Navalny's blood, urine, skin samples and his water bottle. At the same time, the OPCW report clarified that Navalny was poisoned with a new type of Novichok, which was not included in the list of controlled chemicals of the Chemical Weapons Convention.
A-230 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. A-230 is possibly the most potent nerve agent for which specific toxicity figures have been published, with a human lethal dose estimated to be less than 0.1 mg. However it was felt to be less suitable for weaponisation than other agents such as A-232 and A-234, due to issues with the liquid agent exhibiting low volatility and solidifying at low temperatures, as well as poor stability in the presence of water.
A-242 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. Mirzayanov gives little specific information about A-242, stating that it is highly toxic but no figures are given to compare it to other related agents. It is reportedly a solid rather than a volatile liquid as with most nerve agents, and in order to weaponise it successfully, it had to be milled into a fine powder form that could be dispersed as a dust.
A-262 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. Mirzayanov gives little specific information about A-262, stating that it is highly toxic but no figures are given to compare it to other related agents. It is reportedly a solid rather than a volatile liquid as with most nerve agents, and in order to weaponise it successfully, it had to be milled into a fine powder form that could be dispersed as a dust.
Lev Alexandrovich Fyodorov was a Russian chemist.
The State Research Institute of Organic Chemistry and Technology (GosNIIOKhT) is a Russian research institute engaged in the development of chemical technologies for use in the national economy and the production of relevant goods and products.
