The Russian name, in translation, sounds innocuous, even jaunty: “newcomer”, “novice” or “new boy”. But the Soviet-developed family of advanced nerve agents collectively known as Novichok is among the deadliest substances ever created by humankind. The German government on Wednesday announced “unequivocal” proof that hospitalised Russian anti-corruption crusader Alexei Navalny, who fell gravely ill August 20 while aboard a domestic flight, was poisoned by a military-grade agent from the banned Novichok group. Nearly two weeks after being stricken, Navalny, 44, remains in a medically induced coma, his condition described as stable. Amid an international outcry, he was brought to Berlin two days after his hospitalisation in Siberia. Russian doctors who initially treated him denied any sign of poisoning, suggesting – ludicrously, critics said – a metabolic disorder such as low blood sugar. Western outrage after Putin critic Navalny ‘poisoned with Novichok’ Little was known of the Novichok family of toxins until 2018, when they were used in the English city of Salisbury in the attempt to kill a Russian ex-spy, an attack that Western agencies blamed on the Kremlin. Development This class of organophosphate nerve agents was the fruit of a Cold War-era effort by the then-Soviet Union to develop chemical weapons. Operating under the code name Foliant, the programme created a number of Novichok variants, continuing into the early 1990s. Russian scientist Vil Mirzayanov, who disclosed the programme’s existence before he defected to the West, wrote a 2008 book about secret Soviet-era chemical weapons experimentation. Now 85 and living in the United States, he has freely voiced his suspicions about Novichok’s continuing use. Russia has said the development of Novichok was halted by 1992, a year after the break-up of the Soviet Union. In 1997, Moscow joined the Chemical Weapons Convention, which last year put Novichok on its list of controlled substances, in effect banning it. Effects on humans They are agonising, by all accounts. Novichok is part of a class of cholinesterase inhibitors, which prevent nerves from giving “messages” to muscles, triggering a cascade of collapse of bodily functions. Early signs of exposure include constricted pupils and ringing ears, followed by convulsions, vomiting and difficulty breathing as the lungs fill with fluid. Several Novichok variants are far more toxic and powerful than the deadly VX nerve agent, which was believed to have been used by the North Korean government in 2017 to kill the half-brother of North Korean dictator Kim Jong-un. Russia tells UK victim he would have died if Moscow was behind Salisbury attack Soviet scientists got a grisly glimpse of the effects when one of Novichok’s developers, Andrei Zheleznyakov, was accidentally exposed to residue in a laboratory mishap in 1987. He survived, but suffered debilitating ailments that were thought to have directly contributed to his death five years later. “It’s got me,” he was said to have told lab colleagues at the time. Novichok toxins are thought to be used in the form of an ultrafine powder, or like other nerve agents, in liquid or vapour form. Atropine antidote The Charite hospital in Berlin has said Navalny was being kept in a medically induced coma and treated with the antidote atropine. This relieves symptoms by blocking acetylcholine – a chemical transmitter that controls muscle contraction. Nerve agents attack the enzyme that controls acetylcholine, leading to an overproduction and muscle malfunction. With time, the body clears out the nerve agent and starts producing the acetylcholine-controlling enzyme itself. “But in the main it is wait-and-see – you have to wait for the body to break down the non-functioning cholinesterase enzyme and produce more, and this can take a long time,” said Richard Parsons, senior lecturer in Biochemical Toxicology at King’s College London. Risk to others In the Salisbury poisoning, former Russian double agent Sergei Skripal and his daughter escaped death after medical treatment. But the 2018 attack also led to the death of a British woman who came into contact with the nerve agent, as well as injuring several others including a policeman. The decontamination operation in the sleepy Wiltshire town took almost a year and involved a dozen sites. Moscow denied all involvement and insists it has destroyed all of its chemical weapons. Navalny’s supporters believe he was poisoned by a substance in the cup of tea he drank at the airport. Parsons said this may mean the risk to others “may be significantly reduced, but you cannot rule out contamination of other areas, in particular the hospital and the aeroplane”. In adding Novichoks to an annex of the Chemical Weapons Convention’s in November 2019, the global watchdog said it was adapting to “changing threats”. It was the first time that it had been revised since its entry into force in 1997. Tribune News Service, Agence France-Presse