Toxic: A History of Nerve Agents from Nazi Germany to Putin’s Russia 
by Dan Kaszeta.
Hurst, 408 pp., £25, July 2020, 978 1 78738 306 7
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History​ is full of mysterious deaths in which lethal substances are alleged to have been responsible, but the accusation is often misplaced: the tenth-century Byzantine empress Theophano wasn’t responsible for the sudden death of her husband, Romanos II, or the historian Rashid al-Din for the death of the Ilkhanid ruler Öljeitü. Some poisoning stories are no more than rumour, like the one about Augustus and the figs. The most prolific court poisoner may have been the eunuch Bagoas, who is said to have killed two Persian kings before succumbing himself during a failed attempt on the life of Darius III (if you believe Diodorus of Sicily). During the long search for an elixir of life several Chinese emperors succeeded in poisoning themselves.

Cases in which rulers definitely were assassinated by poison can be divided according to the method of its administration. The most common is the Claudian approach: stealth (‘thy uncle stole/With juice of cursed hebenon in a vial/And in the porches of my ears did pour/The leperous distilment’). But some assassins opt for the Laertean method: in 661 Abd al-Rahman ibn Muljam killed Ali ibn Abi Talib, Muhammad’s cousin, with a poison-coated sword. Seventy years later, the Shia imam Muhammad al-Baqir was assassinated by means of a poisoned saddle. In popular culture, poison is a woman’s weapon, probably because of stories about Lucrezia Borgia and the notorious Roman poisoner Locusta, who specialised in belladonna. The historical record, though, suggests it is an aristocratic rather than a feminine tool, one method among many in the long tradition of assassination as the ultimate senatorial check on executive power.

In their book The New Nobility: The Restoration of Russia’s Security State and the Enduring Legacy of the KGB, Irina Borogan and Andrei Soldatov describe the modern Russian state as an intelligence aristocracy, pointing to recent assassinations and attempted assassinations of government critics. Compared to the US government’s global assassination programme, which makes use of drone strikes or special forces, Russia’s efforts are paltry. But poisons are its speciality. Not that America hasn’t dabbled in their use: in September 1960, the CIA agent Sidney Gottlieb travelled to Leopoldville, allegedly on the orders of President Eisenhower, to assassinate the Congolese leader Patrice Lumumba by putting poison on his toothbrush (he was too slow, and Lumumba was killed by Belgian and Katangan soldiers instead).

There is a clear pattern in recent assassinations conducted or attempted by the Russian state. In 2002, the Saudi insurgent leader Ibn al-Khattab died in Chechnya after receiving a poisoned envelope. In 2006, radioactive polonium was put in Alexander Litvinenko’s cup of tea. In 2018, a Novichok nerve agent was administered to Sergei Skripal in Salisbury. The attempted killing of Aleksei Navalny in Tomsk last August is just the latest in a long line of poisonings. Dan Kaszeta’s book is a history of nerve agents and their uses, including technical descriptions of what they are and how they work. Old-fashioned poisons like hydrogen cyanide are blood agents, inhibiting the transmission of oxygen to the body’s cells and causing them to suffocate. Nerve agents affect the muscles, leading to twitching, miosis, involuntary urination and defecation, convulsions, breathing difficulties and finally a fatal shutting down of the lungs. They work by inhibiting acetylcholinesterase, the enzyme that helps break down the body’s chemical neurotransmitter. This leads to a build-up of the neurotransmitter that overloads the nervous system. Very small quantities of a nerve agent – usually a colourless liquid – can be deadly, particularly if inhaled. Some nerve agents occur in nature, like the cholinesterase inhibitor contained in the calabar bean. In coastal West Africa it was used as a judicial aid: a person accused of a serious crime was forced to eat the bean – survival meant innocence, death meant guilt. The cholinesterase inhibitor in the calabar bean is a carbamate, one of the two major classes of nerve agent. The other class is organophosphates, the active ingredient in many insecticides and herbicides.

Synthesis of nerve agents began, almost by accident, at the German chemical conglomerate I.G. Farben. In the 1930s most known pesticides were produced using hydrocarbons. Since Germany had no oil of its own, it made sense to develop them by other means. In 1936, I.G. Farben’s chemists synthesised an organophosphate with a mild fruity smell, which they called Compound 9/91. It turned out to be too potent for use as a pesticide: the lead scientist, Gerhard Schrader, was hospitalised soon after creating it. When it was tested on animals, as little as a milligram proved enough to kill a Barbary macaque. This attracted the attention of the military. Chemical weapons – chlorine, phosgene, sulphur mustard – had been underwhelming in the First World War: perhaps this unintentionally toxic pesticide would be an improvement. German military researchers gave the substance a new name: tabun.

After some difficulty figuring out how to mass-produce it, army scientists managed to load tabun into artillery shells and aircraft munitions. They tested the effects on stray cats because macaques were too expensive. In 1942, the high command ordered factories to be built to manufacture tabun, with concentration camp prisoners conscripted to work in them. Contamination sickness was common and many died. Schrader, meanwhile, returned to his pesticide research at I.G. Farben and synthesised another organophosphate, which he called Substance 146. This was sarin. (The name is an acronym: the ‘s’ is for Schrader and the other letters, according to Kaszeta, honour various functionaries and executives.) Sarin turned out to be even more lethal than tabun. It was also much more difficult – and dangerous – to produce. Again the German military took over and set up a factory at Falkenhagen, but it was slow work.

Schrader is the central figure in the history of nerve agents. Even if he wasn’t at first aware that the substances he was synthesising would be used as chemical weapons, he must have known exactly what was going on when he developed sarin, although Kaszeta concludes that he was a blinkered scientist unconcerned with the practical effects of his discoveries rather than an enthusiastic chemical warrior. In any case, he wasn’t the lone source of nerve agents for long. Two other German chemists, Richard Kuhn and Konrad Henkel, were studying the way nerve agents functioned at the chemical level. As part of their research they synthesised the third compound in what is now called the G series of nerve agents. Soman was twice as powerful as sarin. Fortunately, it was also too expensive to manufacture at scale.

Of all these weapons, only tabun munitions reached the stage of mass production, and thousands of shells and bombs were filled with it. It is still unclear why the German military never used them in battle – perhaps because they were too difficult to move around safely. Kaszeta argues that there may also have been a fear that the Americans had developed similar substances. Despite their deadliness in laboratory tests, neither tabun nor sarin proved the decisive weapon the high command had hoped, though they did enrich I.G. Farben. By November 1944, Germany was losing ground on all fronts and the mass production of tabun munitions was called off.

After the war ended, Germany’s main nerve agent production facilities were taken over by the Soviet army, as was the chemical weapons laboratory in Berlin. US forces intercepted barges carrying tabun down the Danube. Some of it was shipped to Utah, where it was stored until the 1980s. The British army recovered depots containing nerve agent munitions, and sent samples back to the Chemical Defence Experimental Station at Porton Down. More than 70,000 tabun bombs were shipped to Britain and piled up on disused runways in North Wales. In 1954 they were towed out into the Atlantic and sunk. But far from giving up on chemical weapons, the British government launched its own programme. British officials tried, without success, to persuade Schrader to move to Cambridge – but even without him, a sarin factory was set up in Cornwall in 1953. At Porton Down, a new nerve agent, VX, was synthesised and the recipe shared with American military scientists. Kaszeta mentions in passing that, after the war, along with its imperial possessions Britain lost access to chemical weapons testing facilities abroad. At Rawalpindi in the 1930s the British had tried out the effects of sulphur mustard on Indian soldiers. Happily, such large-scale testing wasn’t possible for the nerve agent programme, and military chemists had to make do with a few impoverished volunteers in Wiltshire.

In the US, nerve agent weapons were produced on a predictably larger scale. Sarin was mass-produced in Colorado and more than a million artillery shells, half a million M55 rockets and a large number of bombs were made to deliver it. They tended to leak. In Indiana, the US army manufactured VX and the munitions to put it in, including tens of thousands of landmines. In testing facilities in Maryland, soldiers were subjected to experiments with sarin and VX. Some of the vast stocks of American sarin and VX weapons were held in Japan and Germany but – unlike napalm, Agent Orange, depleted uranium and nuclear weapons – they were never used. Small numbers of nerve agent munitions remain in US army depots.

Although the Soviet Union inherited Germany’s chemical weapons facilities, it benefited less from them than one might imagine: some had been sabotaged during the German retreat. Kaszeta’s account of the Soviet nerve agent programme owes much to the published research of two Russian chemists, Lev Fedorov and Vil Mirzayanov, and to Jonathan Tucker’s 2006 book War of Nerves. Tabun and sarin were manufactured at factories in Beketovka, but the Soviet programme lagged behind that of the US. The Soviet equivalent of Porton Down and the Edgewood Arsenal in Maryland was the State Scientific Research Institute of Organic Chemistry and Technology, or GOSNIIOKhT, which was tasked with recreating the VX developed at Porton Down, but it was misled by false information planted by American intelligence officers: the result was an inferior compound, known as R-33. After this setback GOSNIIOKhT set out to synthesise an entirely new class of nerve agents, safe from potential Western meddling. In the 1970s it succeeded. The resulting compounds – A-230, A-232, A-234, A-242 and A-262 – were called Novichoks.

Both the US and Soviet Union refrained from using nerve agents as battlefield weapons. But they were used elsewhere. By 1984, French, German, Dutch, Swiss, Belgian and American companies had supplied enough chemical precursors to Iraq to enable it to produce modest amounts of tabun. It was used, with the help of American satellite imagery, in the Iran-Iraq War, and nerve agents contributed to the Halabja massacre – without much objection from Saddam Hussein’s Western backers. Later this record would play a part in justifications for the invasion of Iraq.

Little information has been published on the Syrian government’s nerve agent programme before the civil war broke out in 2011, but sarin was used in the government attacks on Khan al-Assal and Saraqib. It was employed again in the much larger Ghouta attack in August 2013, in which between 300 and 1500 people were killed. Since Obama had declared that Assad would be crossing a ‘red line’ if he used chemical weapons, there were fears that the Iraq WMD debacle would be repeated to justify increased American military intervention. Some, including Seymour Hersh in the LRB (19 December 2013), argued that Ghouta might have been a false flag operation conducted by rebel factions with Turkish support, but the weight of evidence suggests that the attack was carried out by the loyalist side. In 2017, sarin attacks on al-Lataminah and Khan Sheikhoun prompted a US cruise missile strike.

Kaszeta was involved in the debate over Ghouta, so it isn’t surprising that he reprises his arguments here. But it still isn’t clear how effective nerve agents actually are as a weapon of war. Terrible though the Ghouta attack was, it contributed a tiny fraction of the civil war’s casualties. Sarin munitions, alongside chlorine gas, seem to have penetrated underground bomb shelters, and were effective against unprepared victims in Iraq and Syria. But they were hardly transformative, even before taking into account the bad press they tend to attract.

If nerve agents​ , contrary to their reputation, haven’t been much use as battlefield weapons, what of their uses in the more delicate art of assassination? Assassination attempts with nerve agents haven’t been the exclusive preserve of the Russian state. In February 2017, Kim Jong-nam, the exiled former heir to Kim Jong-il, was attacked in Kuala Lumpur’s international airport. Two women, one Indonesian and one Vietnamese, possibly recruited by North Korean intelligence officers, threw VX in his face and held a cloth over his mouth; he died in an ambulance on the way to hospital. This success may have helped inspire the assassination attempt the following year on Sergei Skripal, the former Russian spy and defector, with the Novichok A-234. The results were less impressive. Skripal and his daughter, Yulia, quickly received treatment with atropine, which counteracts the effect of cholinesterase inhibitors. The Skripals survived, but a local woman, Dawn Sturgess, was killed after her partner picked up the discarded perfume bottle the poison had been carried in. All the details of the plot came to light, including the identity of the assassins. In short, it was a fiasco.

Kaszeta’s account of the renaissance of nerve agents ends with the Skripal case, which showed that ‘nerve agents are not merely of historic interest.’ His point was reinforced a month after his book was published. On 19 August last year, Aleksei Navalny was visiting the city of Tomsk when members of Unit 34435 of the FSB’s Criminalistics Institute entered his hotel room and applied a Novichok to his underwear; he fell ill the following morning on a flight back to Moscow.* He later described the poison’s effect: ‘You feel no pain, but you know you’re dying.’ The plane was landed in Omsk, but Navalny slipped into a coma. He was spirited out of Russia to receive medical treatment in Berlin, where the presence of a nerve agent was detected, with the Organisation for the Prohibition of Chemical Weapons confirming the finding. He emerged from the coma two weeks later.

That the poisoning was conducted by the Russian state was never really in doubt, but an investigation carried out by Cristo Grozev of Bellingcat with Navalny’s team, the Insider, Der Spiegel and CNN confirmed it. By exploiting Russia’s poor data protection laws and obtaining black market airline booking data and phone metadata, they were able to uncover the identities of the men who had been tailing Navalny. Three FSB officers, Ivan Osipov, Vladimir Panyaev and Aleksei Aleksandrov, had followed him to Tomsk. Their identities were traceable to the FSB’s Criminalistics Institute. The black market data was so extensive that CNN was able to find and visit the house of one of the FSB men. Navalny, posing as a superior officer, recorded a 45-minute phone conversation with another member of the FSB unit, Konstantin Kudryavtsev, who described the whole operation. In a country where you can buy the phone logs and location data of intelligence officers for a couple of hundred euros it is hard to keep secrets.

The Russian government claims that the whole affair was made up by the Americans. If the state had wanted to kill Navalny, Putin said, ‘we would probably take it to the end.’ The fact that such a denial was necessary is evidence of how badly the operation went. The poison was successfully administered but the assassins didn’t account for the possibility that Navalny’s flight would be grounded: the intervention of medics in Omsk was critical. In the end it was more of a disaster than Salisbury. For Putin, Navalny has been an irritant for years. Navalny himself believes that the attempt to kill him was provoked by his decision to run in the 2018 presidential election. The revelations his team have made, often with humour, about Putin and his family have been embarrassing for the government. But before the assassination attempt Navalny’s significance to Russian politics was limited. The poisoning, his arrest on returning to Russia and his hunger strike appear to have increased his influence, prompting street protests and a large number of arrests. His message, that Putin and his clan are not sincere nationalists but self-interested thieves, is essentially a conservative one, which is the reason that it’s threatening.

The US and European national security establishment has unsurprisingly sought to frame the scandal in a way that suits them. In Britain, the Royal United Services Institute called the Navalny poisoning an act of ‘chemical warfare’. The former UK national security adviser Mark Sedwill claimed that the Salisbury poisoning was ‘the first use of chemical weapons against a country in Europe in a century’. But not all forms of violence of which one disapproves are acts of war. A sarin bomb dropped from an aircraft is chemical warfare. The case of the poisoned underpants was a botched attempt on the life of a political opponent. A better comparison for Russia’s nerve agent assassination programme is drone assassinations, which are much less discriminate than poisons. But the easy conflation of poisoning and war has become so routine for British national security officials, journalists and politicians that they seem no longer capable of distinguishing between their own thoughts and propaganda.

Why choose a nerve agent over a hail of bullets, as used in the assassination of the Iranian nuclear scientist Mohsen Fakhrizadeh, probably by Israel, in November? The logic behind using nerve agents in the Skripal and Navalny cases was that the target could be poisoned through contact with their own belongings, a method that allowed the would-be killers to operate at a safe distance. The death would be formally deniable but the result plain enough to send a message. In both cases the plot ran into the classic problem for assassins: the difficulty of actually killing the victim. It’s surprisingly common for people to survive assassination attempts, particularly when single gunshots or explosives are used. The recent record of attempted nerve agent assassinations leads to the suspicion that they, too, are a poor choice of weapon. Contrary to popular belief, they aren’t always fatal, since they aren’t quickly absorbed through the skin (death is quicker if they’re inhaled, or enter through the eyes). They’re expensive to produce and their effects can be treated with atropine. In this respect they aren’t a dramatic improvement over traditional poisons: hydrogen cyanide, pentobarbital, potassium chloride – or fentanyl derivatives of the kind used in the attempted assassination of the former Hamas leader Khaled Meshal in 1997 – do just as good a job. A mundane explanation for their recent use is that the FSB unit in charge of assassinations happens to be the division that oversaw the old Novichok labs. They used what they had.

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Vol. 43 No. 10 · 20 May 2021

Tom Stevenson, writing about the history of nerve agents, records the synthetic work carried out at I.G. Farben from 1936 onwards (LRB, 6 May). He doesn’t mention the work carried out in England in the late 1930s, much of it secret for many years and for obvious reasons. One of the leading scientists in this endeavour was Bernard Saunders, who was my PhD supervisor in the late 1960s. I recall asking him how his thinking had led to the development (and, indeed, the large-scale manufacture) of such unpleasant compounds. He replied that two of the most toxic elements in the periodic table were phosphorus and fluorine, so the idea was that synthesising compounds containing both might be a promising approach to making very toxic chemicals. His monograph Phosphorus and Fluorine (1957) records in surprising detail his work on nerve agents, their synthesis and properties. In it he gives a full account of ‘testing’ one of the early compounds, di-isopropyl fluorophosphate (DFP), on himself, at the one part per million level, in a specially designed cabinet. The frontispiece of the book shows the effect on the pupil of one of his eyes (a pinpoint). He never attempted to justify this work as anything other than necessary preparation for war or potential war, though the subsequent development of phosphorus-based pesticides might have been some justification. To the end of his life he remained a committed Christian.

Peter Baker
Prestwood, Buckinghamshire

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