THE IDEA OF POISONING — radioactive or otherwise — is not new to Russian intelligence. According to former Russian intelligence officer Boris Volodarsky, now a historian and one-time associate of Litvinenko, the Russians have a history of substance assassination going back nearly a century. It was Lenin who ordered the establishment of their first laboratory, known simply as the ‘Special Room’, for developing new lethal toxins.

“There is also a long succession of poisonings by Russian intelligence services in different countries, starting in the early 1920s,” he says.

At its height, says Volodarsky, the Soviet Union had the largest biological warfare program in the world. Sources have claimed there were 40,000 individuals, including 9,000 scientists, working at 47 different facilities. More than 1,000 of these experts specialized in the development and application of deadly compounds. They used lethal gasses, skin contact poisons that were smeared on door handles and nerve toxins said to be untraceable. The idea, at all times, was to make death seem natural — or, at the very least, to confuse doctors and investigators. “It’s never designed to demonstrate anything, only to kill the victim, quietly and unobtrusively,” Volodarsky writes in The KGB’s Poison Factory. “This was an unbreakable principle.”

Murderous poisons come in three varieties: chemical, biological, and radiological. It’s believed that the first Soviet attempt at a radiological assassination took place in 1957. The target was Nikolai Khokhlov, a defector who had left for the United States a few years earlier. He became drastically ill after drinking coffee at an anti-communist conference he was speaking at in West Germany. After his collapse, he was successfully treated at a US army hospital in Frankfurt for what was believed to be poisoning by radioactive thallium.

In the years before Litvinenko’s murder, a series of other killings bore similar hallmarks. In 2004, Roman Tsepov, a prominent and controversial political operative from St Petersburg, died after being poisoned with an unidentified radioactive substance on a visit to Moscow. The year before, Yuri Shchekochikhin had died in similarly mysterious circumstances. An investigative journalist and member of parliament, he had exposed a series of scandals, including an FSB racket that laundered money through the Bank of New York. His death came after a brief, undiagnosed illness with familiar symptoms: hair loss, vomiting, red blotches, fatigue. He was due to fly to the United States to meet FBI agents just days later.

The Russians may not be the only ones to have used nuclear technology for targeted execution, however. East Germany’s secret police, the Stasi, are alleged to have used radioactive poisons and even deployed modified x-ray machines to irradiate and injure political prisoners. They also used radiation as a tool, surreptitiously tagging dissidents with chemicals so they could trace and track them with Geiger counters.

And in November 2013, scientists in Switzerland announced that they had found heightened levels of polonium in the remains of the former Palestinian leader, Yasser Arafat. Investigations began two years previously, when researchers discovered the strange news that some of the personal items that Arafat had been wearing shortly before his death appeared to be contaminated with high levels of polonium-210 and were emitting alpha radiation. It was a finding that raised difficult questions for those who may have wanted to get rid of him.

But still, Russia’s ability to source and use radioactive poisons seems to be pre-eminent. Only about 100 grams of polonium are manufactured each year, and just three countries are known to produce it reliably: Israel, the United States, and Russia. And 97 percent of that supply is manufactured in one place — a converted nuclear weapons facility that operates under high security, on the banks of the Volga, 450 miles south east of the Kremlin.

The case for official Russian involvement in Litvinenko’s death was growing. And there was more evidence to come: unbeknown to them, the assassins had left a trail — and it seemed to lead east…………

This story was written by Will Storr, edited by Deborah Blum, fact-checked byFangfei Shen, and copy-edited by Rupert Goodwins. The illustrations were by Ed Tucker, and the audiobook was narrated by Ian Parkinson.  https://medium.com/matter/how-radioactive-poison-became-the-assassins-weapon-of-choice-6cfeae2f4b53