Jane VaynmanAssassination by Polonium

Everyone has probably caught the bits and pieces of headlines on the former Russian spy, Alexander Litvinenko, who was poisoned and died last week. There is little conclusive information and the assassination has been linked in the press both to the murder of Russian journalist Anna Politkovskaya and the Yukos affair. It’s a James Bond style mystery, but in that great BBC news voice.

The interesting part is that he was poisoned with polonium-210, an extremely rare and highly radioactive element. It is even rarer in quantities that could be used for poisoning, since they would have to be manmade. Most of the news sources are quoting experts as saying that the Po-210 could have only been produced in major laboratory. This point makes the theories (which I will describe below) about Litvinenko’s death very troubling from the standpoint of securing access to radioactive materials.

What’s Polonium-210 and where do I get some?

Polonium-210 is highly radioactive with a half life of 138 days. A very small amount, about the size of a pin head, would be enough to kill an exposed person. Exposure means swallowing or inhaling; although polonium-210 releases large amounts of alpha particles as it decays, these particles would not for example be able to penetrate your skin. (Take a look at this basic overview on Po-210 which the Royal Society of Chemistry put up on the web recently.)

Polonium-210 is often used as a neutron initiator in nuclear weapons, although it does have some civilian uses (batteries for satellites). Iran was found to have done Po-210 experiments in 2004, raising IAEA concerns. Polonium-210 of a substantial quantity would had to have been produced with a particle accelerator or nuclear reactor. Here is where all eyes turn to Russia. (Oh, beside of course Litvinenko also being a Russian spy and blaming Putin for poisoning him. That’s too obvious.)

The Observer (UK) points out why Russian institutes seem like a like source:

Such material, it is believed by experts, could only have come from the massive nuclear structures of the old Soviet Union where, during the collapse of the empire, security was often sacrificed. Polonium can only be gained from such reprocessing plants or equally complex nuclear research plants. You cannot buy this stuff from local criminals.

The speculations about this case generally fall into two groups: intentional the Russian government (or governmental organization) or intentional by someone who just had it out for this guy. (There is no evidence yet that the material did come from Russia. They detected Po-210 in Litvinenko’s body, the restaurant where he ate day he got sick, a hotel, his home, and a few other locations.)

Neither of these theories makes me feel any better about the security of radiological materials.

Assassination Theory 1 – The FSB, or someone otherwise acting on orders of the Kremlin.

The Kremlin wanted Litvinenko gone, they gave the word to someone (FSB, etc) and voila. The access to the radioactive material was easy though a number of Russian nuclear facilities.

There are several problems with this theory. If the material does turn out to be Russian, and traceable, then why would any government sponsor have chosen this particularly self incriminating method of assasination? The Moscow Times quotes Alexander Pikayev on this point:

[Alexander] Pikayev said that if a Russian intelligence agency had wanted to kill Litvinenko, it would have been foolish to use polonium because its source could probably be traced.

This of course does not rule out the FSB involvement. They could have just gotten non-Russian polonium-210, or even acted without Kremlin directive or approval. The government-sponsor or government agency theory leads to two possible conclusions: 1) Russian secret services like using overly elaborate and exotic assasination techniques 2) to high powered buyers, radioactive materials are available from either in Russia or perhaps even other sources. Since polonium is very difficult to make, only countries with highly developed nuclear programs have this capability. So where else did it come from?

note: Jeffrey pointed out that polonium-210 may be very difficult to detect, especially in a poisoning case where symptoms may suggest other substances, making this not such a crazy sounding approach after all. Perhaps those carrying out the attack actually hoped that it would leave not evidence, but miscalculated on dosage.

Assassination Theory 2 – One of Litvinenko’s many many enemies

No one denies that Litvinenko had many enemies. Perhaps one or several of these enemies acquired some polonium-210 from a less than perfectly guarded or bribe-able source, and carried out the attack independently.

However, some experts argue that this kind to lone attack would not be possible without government sponsorship and sophisticated technology.

“No individual could do this,” said John Large, an independent nuclear consultant. “What you are talking about is the creation of a very clever little device, a designer poison pill, possibly created by nanotechnology. Without nanotechnology you would be talking about a fairly big pill, a pea-sized pill. Either way you are looking at intricate technology which is beyond the means and designs of a hired assassin without a state sponsor.”

So far, experts have not found prior cases where polonium-210 was used as a poison.

Going with the non-government independent assassin theory is perhaps even more disturbing than FSB agents running around poking people with umbrellas or what not. It means that an extremely well prepared person or group of people managed to get their hands on a deadly radioactive substance which most seem to think is nearly impossible to acquire.

Regardless of which theory is true (and of course there are others), this incident also shows that it was clearly possible to smuggle polonium-210 into the UK. (Alpha particles do not set off radiation detectors.)

Lastly, an interesting side note. The Russian press is covering this story a bit differently. The papers are generally not touching the theory of a Kremlin sponsored assassination. Rather, they focus on other theories including some of their own, involving even Chechen militants, and comment on the British investigation.


  1. Georg Schoefbaenker (History)

    In the U.S. everyone can order PO-210. By post.


    PO-210 costs 69 U.S. $. So, nobody needs a state actor involved though it is most likely that state actors are a part of the assassination.

  2. Michael Roston (History)

    Good work, Jane. Questions that arise include:

    1. Is it illegal to use radiological weapons? Clearly, this act would be illegal on other grounds. But I’ve been thinking through my treaties and don’t know of anything that bans outright the use of radiological weapons. That’s a shame, and clearly this incident points to the need for a new treaty regime to outlaw use of radiological weapons by states and non-state actors.

    2. If Russia is responsible for this, can the United States continue cooperation with the country in socalled Radiological Device protection control and accounting under the Global Threat Reduction Initiative? Some will certainly say no.

  3. Alex (History)

    You’d have some trouble accumulating enough $69 samples and preparing them into a deliverable form before they decayed (half-life=138 days), and I like to think UnitedNuclear would notice someone buying half a million bucks’ worth of the stuff.

  4. J. (History)

    To Micheal – I don’t know what laws exist in the United Kingdom on the lethal use of radiological material, but I can tell you that it’s a federal crime in the United States. The DOJ got Congress to pass a section in public law back in 1994 (not sure exact reference) on use of WMD. And by WMD, they meant any chemical, biological, radiological, or nuclear material used in a crime or terrorist act, irrespective of amount or mass casualty potential.

  5. Laurens (History)

    The license exempt sources sold for $69 by United Nuclear and others can only be bought in limited quantities, so you would have to set up a few thousand shell addresses to get deliveries. Then you have the problems Aex mentions of getting the stuff out of the “holder”. Unfortunately the assumption that any level of radiation is as dangerous as the milliCurie level implied here is all too common. If it were true we would all be dead from background radiation.

  6. mark gubrud (History)

    1. “Polonium-210 is often used as a neutron initiator in nuclear weapons” – Often? With a half-life of 138 days, thus requiring frequent replacement? I think this refers to the days of Fat Man and perhaps a threshold state such as Iran. Modern weapons use spallation tubes, right?

    2. ”…a designer poison pill, possibly created by nanotechnology. Without nanotechnology you would be talking about a fairly big pill, a pea-sized pill.” What does this mean? You need a little bit of Po-210 in an ingestible form. Nothing here has anything to do with anything conventionally known as “nanotechnology.”

  7. mark gubrud (History)

    3. I get 32,467 $69 0.1uCi samples needed to amass 1 ug of Po-210, so that’s $2.24M, definitely an expensive hit, if you don’t have a direct line to the supplier.

    4. The fact that it took 3 weeks to kill Litvinenko suggests that the dosage was actually pretty well calibrated, within a factor of ten or so of the minimum in order to ensure prompt death.

  8. mark gubrud (History)

    5. Please, folks, this isn’t cute. A man was murdered, apparently because he stood up to Putin and the FSB. Maybe they didn’t do it, but it sure looks like they did. Maybe they thought it was okay because he was an ex-spy. But it sure says some ugly and disturbing things not only about nuclear security but about the Putin gang and the state of law and morality in this world. Oh and our own little post-9/ll dictatorship has certainly set a great example, eh?

  9. mark gubrud (History)

    [Correction] It would take 45,000 $69 orders of Po-210 to make 1 ug. That’s $3.1M.

  10. Haninah

    Great post, Jane! It seems to me like some of the theories floating around the media are really missing the significance of the short half-life aspect… for example, given the half-life, it’s not really relevant to this story that Russian facilities were unsecured when the USSR collapsed (forty half-lifes ago). All that’s relevant to the materials-theft hypothesis is how well-secured they are today. More generally, the fact that the material has to be so fresh to be useful tips the balance in my mind towards explanations that involve a well-organized, holistic operation…

  11. Alex (a different one) (History)

    If the material does turn out to be Russian, and traceable, then why would any government sponsor have chosen this particularly self incriminating method of assasination?

    How about: to send a message?

    One which reads: “We’ll kill you, no matter where you are, not matter whether you are a trained KGB agent or not; we’ll do it with impunity, and with painful, scary, slow-killing, exotic weapons. So don’t think you can flee the country and then tell our little secrets to anyone else. Keep your mouth shut or die a lonely—bald—martyr’s death.”

    That’s my little theory, anyway. If we don’t assume that Russia really thinks that killing one of its former spies is going to result in any real international difficulties, the whole thing becomes a much simpler question. I don’t think Putin is worried much about accountability at this point, if he ever was in these sorts of affairs.

  12. Iouli Andreev

    It is strange, but nobody mentioned that in Russia it is common opinion that both Politkovskaya and Litvinenko were killed by Russin criminal billionere Beresovosky. Не currently lives in London under the patronage of the UK government.

  13. Alex (History)

    Alex (not me), that is close enough to my opinion that it could have been “Alex (me)” who wrote it.

    Maybe it was?

  14. superdestroyer

    According to the National Council on Radiation Protection and Measurements Report 65, an acute lethal dose of polonium-210 would be 36 microcuries/kg. For a 200 pound adult that is about 3 millicurires.

    You can buy a 31 millicurie source (static eliminator) for $229 http://www.ricelake.com/docs/viewProduct.php?productID=91906

    However, if Mr. Litvinenko ingested the polonium, the lethal dose will be higher than 3 millicuries since the fraction that is absorbed by the gut is very important (it is refer to as the f value).

    Also, I believe that the hair falling out is not a symptom of acute alpha particle toxicity. According to animal studies, polonium will deposit in the lung, liver, muscle, lymph modes, kidney, spell, and blood. Destroying the hair folicles without developing edema should raise suspicions that the poison was not polonium.

  15. lucabrazi (History)

    Nothing cute about this and even a facetious comparison of our “own little post-9/ll dictatorship” to Putin’s thugish regime in downright insulting and obscene. It’s this sort of mindless partisan snark than undermines the value of discussions like this.

  16. jane (History)

    Responses to several comments:

    On Polonium 210 and hair loss, the impression I got from several articles was that hair loss would be consistent with polonium exposure. From NYT: “The particles disperse through the body and first destroy fast-growing cells, like those in bone marrow, blood, hair and the digestive tract. That would be consistent with Mr. Litvinenko’s symptoms, which included hair loss, inability to make blood cells and gastrointestinal distress.”

    In response to Iouli Andreev’s comment about Berezovsky, I am not clear on the relationship between him and Litvinenko (and I doubt that anyone is). Traces of radiation were found in Berezovsky’s London office. He recently released a statement saying how saddened he was by the death of his close friend.

    Lastly, Mark is right, polonium-210 with beryllium was used as an initiator in early nuclear weapon design. More on history of uses and production of polonium here.

  17. pflatlyne (History)

    The idea that the Russian government would use polonium to poison someone does seem odd on its face,however there might be reasons. Nuclear materials in Russia are poorly guarded and he DID have enemies other than the Russian government which gives them a level of deniability. On the other hand, other critics of the Russian government probably believe that they carried out the assination. Perhaps it was meant as a warning. Something that their critics would understand as being definitively the work of the government,but that they could plausibly deny to everyone else. Had he been shot, it wouldn’t look so bad for the Russian government. On the other hand,its really all speculation. Certainly there were a lot of people that wanted him dead.

  18. Mike (History)

    With regard to the static eliminator source of Po-210, would not the Po-210 be in a chemical substrate and thus difficult to extract for another use?

  19. Jeffrey Lewis

    I have to say that, much though I find the Bush Administration to be a disappointment, the Putin regime is truly odious. No comparison.

  20. got mercury (History)

    I thought Wiki tells that the lethal dose of polo 210 is 6.8×10-12 g. Close to six orders of magnitude under the 1 ug that mark is amassing. That makes Polo 210 a very cheap hit. Look out for our reservoirs!

  21. jane (History)

    The discussion of the Russian government being involved has another interesting aspect, which I notice comes up more in my conversations in Moscow (with both Russians and foreigners). Referring to the Russian government can be very misleading, as it is far from monolithic, especially when talking about the FSB. The involvement the FSB does not necessarily mean that there is a connection to the Kremlin or to Putin. Putin is the public face of Russian policy, but it is also very possible that policy is made and carried out by other actors, over which the extent of his power is unclear.

    Also, there is much ado today about how you can buy polonium-210 over the internet for $69 dollars. There was some in the Russian commentary, and probably in the western news too. A number of people asked me today if I knew what that was all about, “Have you seen that website selling polonium!?” Thank you ACW readers for not only pointing out that site ago but also calculating that it would be rather expensive and probably unfeasible to buy enough online. And all a day ahead of the media commentators. MSNBC’s blog has an explanation about this website which also says that, “The radioactive samples that United Nuclear is selling over its Web site are encased in disks of inert material, or planchettes, as a safety measure, and thus aren’t considered all that hazardous, Eckerman told me. ‘It’s physically bound to that substrate, so it’s not possible to mechanically remove it,’ he said. ‘You’d have to dissolve the whole planchette.’”

  22. Jim (History)

    The 6.8×10-12gr mentioned by gotmercury is the maximum permissible body burden. This is a quantity not expected to result in any health effects in a persons lifetime. It would take a much larger quantity to be lethal in a manner of days.

  23. Andy (History)

    Not much to add except that United Nuclear has updated its isotope website with a good explanation of why their products can’t be used as a poison.


  24. Cody

    Po-210 is part of the natural U-238 decay series, and it has been indicated as a primary contributor to the cancer risk associated with smoking. It is deposited from the atmosphere onto the broad leaves of tobacco plants, and from there it makes it way to the smoker’s lung.

    Death from acute radiation poisoning generally occurs through one of 2 avenues. At the lower end of the lethal dose range, the cells that absorb nutrients from the digestive tract are destroyed. The victim then proceeds to die over a period of weeks. Medical recovery is possible, but requires quite a heroic effort.

    The other avenue occurs at higher doses, and is the result of central nervous system failure. The system failure is caused by the breakdown of a protective barrier that nerve cells have. Death can be instantaneous or slow as the victim dies from loss of nervous control.

    Ingestion of Po-210 would seem to lead to the gastro-intestinal syndrome, and this is fairly well aligned with the timeline of Litivenko’s death. It does not seem that the dose was high enough to produce central nervous system failure due to the relatively long hospital stay.

    GI-failure is treatable, yet the spy is dead. I’m not convinced that acute radiation syndrome is the cause of death.

  25. Mark Gubrud (History)

    * The discussion about United Nuclear’s $69 Po-210 alpha sources was made moot by “superdestroyer” pointing out that far stronger sources, sufficient for someone with sufficient knowhow to glean a lethal dose, are available commercially, embedded within antistatic devices. This means that it is possible, if doubtful, that Litvinenko was poisoned with Po-210 prepared by someone not working for the Russian or another government.

    * The United States under President Bush has used assassination and extrajudicial execution (as well as torture) as instruments of national policy. Bush referred to this openly in his 2003 State of the Union address:

    All told, more than 3,000 suspected terrorists have been arrested in many countries. Many others have met a different fate. Let’s put it this way—they are no longer a problem to the United States and our friends and allies. (Applause.)

    Our closest ally in the Middle East has openly practiced such “targeted killing” for far longer. The methods we and they have used include aerial bombing, often based on weak intelligence, often killing and wounding many innocent people and often missing the intended targets. We have added a terrifying new dimension with our Predator flying robot assassins.

    Although proof is lacking, the US military has been accused of targeting journalists in Iraq, and in any case, Bush’s unjustified and illegal invasion of Iraq has caused about a half-million deaths.

  26. Voyager (History)

    “Micheal – I don’t know what laws exist in the United Kingdom on the lethal use of radiological material”

    Well you simply don’t get access to it at all. 130 institutes are licensed to handle it in the United Kingdom, but they don’t get to take it on planes to/from Moscow.

    This would be an easy weapon in countries which did not have Atomic Weapons Establishment scientists to trace it………and it is not only polonium 210 they expect to find, but other metals too.

    If Putin didn’t order this execution he should hire a few food-tasters himself.

    WE don’t like people flying in from Moscow to murder a British Citizen in London; it is very impolite of the FSB to be so obnoxious when 14.000 Russians live in London

  27. Jarhead (History)

    As Stephen Colbert put it, forget negative campaigning and attack ads, just plain attack you opponents, literally.

    Per Colbert: Putin has demonstrated by this case just the kind of strong and decisive leadership on “nuclear issues” that Bush has shown himself incapable of to date. Putin ‘08?

  28. Mikhail Krylov (History)

    Though some Russian media are different, nearly all media of nation-wide coverage assume that the Kremlin sponsored assassination was not possible.

    But it not necessary is a result of the Kremlin having gotten ahead of the game in news coverage. There is at least one other relevant explanation for media being eager to blame everybody except the government.

    The Kremlin sponsored assassination theory is not favored by Russian media partially because there generally is easier to be an expert, or seem to, when there is no data in your realm of expertise. The more evidence you have the longer time it takes to read. If one assumes a Kremlin involvement was possible, there is need to analyze current politics, which is either way difficult. If not, then the only pertinent framework is confrontational. That discourse is the most comfortable for many analysts.

    In addition, there is no hard evidence yet for any theory, and if you were Russian, any accusations against the government, even with a catchword ‘allegedly’, would be reprehensible, both morally and judicially.

  29. Jonathan Brooks (History)

    Thought American Elements’ website (www.americanelements.com)would a useful resource—info on Po 210 and 100s of other Isotopes, Nanomaterials, etc. (Disclaimer: I’m an engineer with the company!)

  30. logical? Jon (History)

    There are still many un-answered and un-addressed questions concerning this case. For example, why is the press not concerned with who had access to the food at the sushi bar? Were they all immediately cleared? I haven’t seen such a report. It would seem from the Italian’s report that the most likely route of ingestion would be via the soup. (And what about the report that the Italian government suspects him of dealing in illegal waste disposal? Hmmmm…) If it was the soup, then someone must have placed the Po immediately prior to ingestion since the Italian reported that Litvenenko selected the soup himself. Obviously the entire original batch of soup was not contaminated or all who ate it would be dead. But if the soup was the carrier then why has Po been detected in so many people and at so many locations? Then I wonder if Po is emitted by contaminated persons via exhale or other body emmissions. It’s hard to imagine that an assassin would allow himself to be contaminated and then wander around rubbing Po off on every surface he touched. It then strikes me that an aerosol delivery would explain a lot of the puzzles. If the Po was delivered that way, everyone in the restaurant might have inhaled some of it or gotten some on their clothing. Alternatively, if the soup was hot (>131 F – see http://en.wikipedia.org/wiki/Polonium), some portion of the Po in the soup might have vaporized and become airborne (10 ng is listed as a fatal inhaled dose!) That way, at least the workers and others-in-the-sushi-bar contamination could be explained.