Why would you use this to poison somebody?
I was very surprised, because it's an alpha emitter, which is a heavy ionizer, but generally it's a difficult one to use if you were to have it ingested in food or something like that. One of the things about human beings is that our gut is designed to protect us from being poisoned. So the gut lining doesn't pass toxins into the blood. This would be seen as a metal, and if you look -- health physicists have what they call gut-transfer factors, and the gut-transfer factor for polonium is quite low. Not a lot of it can get through.
The first challenge, if you're going to administer this as a toxin via the mouth or by liquid -- you've got to somehow cut it chemically with something to make it diffuse into the gut and out of the gut into the bloodstream so you can get it into key organs. The way in which you cause the collapse of this victim is to concentrate the radioactivity in a number of key organs: the kidneys, the liver, and in this case in the bone itself, on the bone surfaces. You then get a lack of red blood cells, and the whole system starts collapsing. Now, to do that as an ingested thing is quite difficult. You'd probably need some sophisticated chemical cut into it.
If you could get it into the respiratory tract, down into the depths of the lungs -- and if the particles are small enough, less than, say, 5 millionths of a meter, 5 microns -- then you can pass it through the lung tissue into the bloodstream, where it can do its evil work. Even then, and I haven't done the sums on this, but I would guess to get a lethal dose, about 5 units of radiation, would take some months.
That's what's so strange about this. First of all, how was it administered? Was it administered through the ingestion pathway or the respiration pathway? The respiration pathway would require some quite sophisticated chemistry, and if it was [administered that way], it seems a bit too effective. So was there some trick, not only a chemical trick but a radiological trick, applied to this?
Almost 30 years ago in London, we had the Bulgarian dissident [Georgi] Markov, who was injected with a ceramic pellet from an umbrella. That was very advanced technology for its day, and I'm beginning to sense that this particular radionuclide might be part of a very advanced designer toxin. It may even involve nanotechnology. But it's certainly caught everyone by surprise here; we were just ill-prepared for this.
Everybody's focusing on the sushi Litvinenko ate, but you're talking about the respiratory tract. Do you think it wasn't in the sushi?
I think it was the respiratory tract. [And] I think if it was via the respiratory tract, it would take a lot longer than the sushi bar, so you'd look for somewhere he'd stayed, perhaps for several hours.
But who knows? The problem is, if it was a well-designed toxin, then it could have gone in anywhere. It could have been an injection.
This is absolutely unique. It's an awkward thing to administer, because, as we've seen, it leaves a trail. If you administer this to anyone, it's not only got a radiological half-life, but it's also got a biological half-life. Put this stuff in the body, and an amount of it will come out in a number of days, and it will continue. Most obviously in the urine, but also in sweat. So your victim will leave a trail.
The initial reports were saying this shouldn't have been detectable.
Oh, no, of course it would be detectable. First of all, the initial reports were wrong in that they assumed it was a pure alpha emitter. Well, it's going to have some beta gamma, so that makes it readily detectible. Secondly, the symptoms he was displaying were that of radiation poisoning: loss of hair, low blood count, et cetera.
In Britain we have something similar to your Homeland Security system. We have something called Resilience. Last year we had an exercise for a radiation dirty bomb attack, and the police took over an area of London and displayed how wonderful they were, with all their different-colored spacesuits and chemical suits, and they had police cadets playing the injured, and of course everything went off absolutely smoothly, the disaster was averted and a nation was saved. Of course, [laughs] come, instead of a terrorist with a dirty bomb, one assassin with some polonium, and the whole system just collapses.
