The Demon in the Freezer by Richard Preston

There is a certain genre of American science writing that prides itself in checking facts. So much so, indeed, that professional fact-checking is part and parcel of the editing process. Robert Preston, who uses facts like a builder uses bricks, is gracious enough to acknowledge his own fact-checker, who no doubt had his work cut out with The Demon in the Freezer.

The most astounding fact in Preston's book is that the former Soviet Union, in the late 1980s and the early 1990s, had produced some 20 tons of smallpox virus at its Zagorsk Virological Centre, about 30 miles north-east of Moscow. Such a production facility would have broken just about every rule in the biological weapons book.

After smallpox was eradicated in the wild in the 1970s following a worldwide vaccination campaign, the World Health Organisation co-ordinated the collection or destruction of laboratory stocks. Only two places were officially allowed to retain live smallpox. As Cold War politics dictated, one was in the US and the other in the USSR. The rules stipulated that the virus was only to be used for medical research.

Combining both stocks would have probably filled a container no bigger than a small jam jar, so there is only one possible purpose for producing 20 tons of the stuff. Preston believes the plan was to put it into specially adapted ballistic missiles with refrigerated warheads, in a flagrant breach of the Biological Weapons and Toxins Convention.

Preston's principal sources for these astounding facts were the Soviet bio-weapons defectors, Kanatjan Alibekov (now Ken Alibek) and Vladimir Pasechnik. As the USSR's Ministry of Health was donating smallpox vaccine to the WHO to help in the eradication campaign, its Ministry of Defence was apparently making and stockpiling vast stocks that could be loaded into missiles aimed at Washington or London.

Pasechnik even told his MI6 debriefers that the old Soviet regime had ordered its scientists to genetically engineer the smallpox virus to make it even more deadly than nature intended. This was the last straw for such a principled man. "I couldn't sleep at night, thinking about what we were doing in our laboratories and the implications for the world," Pasechnik told MI6. According, that is, to the facts unearthed by Preston.

Why the Soviet Union would want to unleash smallpox on the world remains something of a puzzle, given that it had enough nuclear weapons to destroy everything and everyone hundreds of times over. It is just possible that Pasechnik and Alibek were elaborating on what they knew to be true in order to gain favour with their new masters. Richard Preston – and presumably his professional fact-checker – obviously doesn't think so.

It is slightly irritating that Preston has fallen into the simplistic Cold War notion of good and evil. He paints a picture of the Russians as persistent and unscrupulous liars who cannot be trusted. Even when they offer their American guests vodka, there is an ulterior motive. American scientists, meanwhile, are the sort of upstanding comic-strip heroes you come across in Hollywood movies. No doubt Preston is already working on the film script.