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Derek Lowe The 2002 Model

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Derek Lowe, an Arkansan by birth, got his BA from Hendrix College and his PhD in organic chemistry from Duke before spending time in Germany on a Humboldt Fellowship on his post-doc. He's worked for several major pharmaceutical companies since 1989 on drug discovery projects against schizophrenia, Alzheimer's, diabetes, osteoporosis and other diseases. To contact Derek email him directly: Twitter: Dereklowe

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« The Paper Mountain | Main | The Litvinenko Case: More On Polonium and Alpha Particles »

November 27, 2006

Polonium Poisoning

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Posted by Derek

I was going to write up a piece on thallium poisoning, until word came out over the long weekend that the Russian spy case was instead an instance of polonium poisoning. That's a very different matter indeed.

For starters, polonium isotopes (like most radioactive substances) are much more hazardous as radiological agents than as chemical ones. Unraveling the two isn't always easy, but this case is pretty clear. It's likely that polonium is chemically toxic, since it's in the same series as selenium and tellurium (which both are), but it's also likely that any reasonable dose would kill a person from alpha radiation rather than from whatever enzyme inhibition, etc., that might also ensue. People have been dosed with fairly robust amounts of tellurium and survived, albeit uncomfortably, but I can't imagine that anyone has been exposed to a systemic dose of a hard alpha emitter and pulled through.

This takes us into the long-standing arguments about the toxicity of such isotopes. Readers who remember the anti-nuke days of the 1970s and 80s may recall the statements about plutonium's incredible toxicity, generally expressed in terms of how miniscule an amount would be needed to kill every human being on the planet. Left unsaid in those calculations was that said plutonium would have to be dosed intermally in some bioavailable form. More Pu was surely vaporized in the atmospheric bomb tests of the 1950s, without depopulating the Earth to any noticeable extent. (See the arguments here, for example).

Here, though, we have a case of that exact bioavailable dosing of a strong radioisotope, with the unfortunate effects that you'd predict. There were some experiments early in the atomic research era where patients were dosed with radioactive isotopes. Oddly, the polonium experiments may have been the only ones that stand up to ethical scrutiny. A good review of what's known about polonium exposure, at least as of 1988, can be found here.

One thing that many people may not realize is that every person on the planet has some polonium exposure. There are many people who equate "radioactive" with "man-made", but those categories don't completely overlap. Polonium is a naturally occurring element, although certainly not in high abundance, but there's enough for Marie Curie to have isolated it. It's part of the radioactive decay series of U-238, and as a daughter radionuclide is a contributor to the toxicity of radium and radon exposure. You've had it - but not like this.

Comments (17) + TrackBacks (0) | Category: Current Events | Toxicology


1. Chrispy on November 27, 2006 3:11 PM writes...

Why the heck would anyone use polonium to poison someone with? It's hard to get, traceable... I mean it's not like the guy isn't going to know he was poisoned as his hair falls out and throat swells shut.

Perhaps the answer is creepier than I had imagined: maybe having the fellow fall victim to a known poisoning sends a message more clearly than having him die of an apparent heart attack (for example). And what is even more horrible is that there is more than one group of people capable to carrying this off in Russia right now -- to the point where the message isn't even clear... Don't piss off the KGB, don't piss off the mob, whatever...

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2. david on November 27, 2006 5:49 PM writes...

I'd suggest that you change "don't overlap" to "aren't the same" or "aren't congruent". As written, it gives the lay reader the impression that "manmade" and "radioactive" are entirely disjoint, which is certainly not the case.

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3. Harry on November 27, 2006 10:06 PM writes...

Well- elemental selenium isn't all that toxic, probably because, as you pointed out, it's not all that bioavailable. In fact, selenium is an essential micronutrient and seleniuum deficiency can result in (IIRC) some sort of cardiomyopathy, which I'm too lazy to look up just now.

I do know that selenium can be incorporated into a number of amino acids (selenohomocystine and selenomethionine for example) and I seem to recall that there is at least one seleno co-enzyme system in humans (although the memory is hazy).

I expect that it may not take a great deal organoselenium to overwhelm the enzyme systems responsible for processing it.

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4. Jan on November 28, 2006 5:45 AM writes...

I worked with selenides and tellurides and read some MSDS etc.. The chemical toxicity of these elements is quite high. H2Te (gaseous) has a LC50 of 1 ppm. Sodiumselenite has a LD50 of 3 mg/kg. I think polonium is even worse. It is not only the radiation...

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5. Harry on November 28, 2006 8:46 AM writes...


I agree with you about the toxicity of Hydrogen Selenide in particular and selenides in general, elemental selenium, (TDLo-480 mg/kg, Oral, mouse)however is not taken up readily and thus is not nearly as toxic as are more available forms.

My work has been mostly with organoselenium compounds (Diphenyl Diselenide, Selenophene, etc), which vary widely in their toxicity.

Certainly Selenium and its compounds are not things to be treated lightly.

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6. Jim Hu on November 29, 2006 8:17 AM writes...

On my site, I noted an argument that smokers have more Po 210 exposure than nonsmokers, and that it is claimed that this is related to increased use of mined CaPhos fertilizers on tobacco, which are contaminated with Radon.

Haven't followed this up in the literature, though.

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7. Craig Reed on November 29, 2006 10:20 PM writes...

Is there some reason that the polonium can't be a breakdown product of some other radioactive substance?

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8. Jon H on December 2, 2006 8:41 PM writes...

"Why the heck would anyone use polonium to poison someone with?"

Well, if Russia wants to send a message to its critics, radioactive poisoning with a relatively exotic material is going to be pretty clear.

If they just shot or poisoned him, for instance, there might be some question of who is responsible - it could also be Russian organized crime, or a Russian oligarch.

Using Polonium makes it pretty clear that the culprit was most likely a government.

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9. Casper on December 6, 2006 8:51 AM writes...

what I like to konw, in this case. What was the killing blade -- chemical toxicity or radioloigcal dose from Po-210? Thank you in advance!

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10. chemist on December 9, 2006 7:56 PM writes...

Although I am not a big fan of Russian goverment, but the entire story seems to be strange. First, the guy wasn't the enemy #1 to the Russian goverment. Second, the last thing Russian goverment wants to do is to look as flash-eating monsters. Third, the poisoned guy wasn't a spy. He was controlling the radioactive material smugglers when he was working in Russia. And, fourth, Russia presidential elections are taking place in a year.

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11. eugene on December 10, 2006 10:35 AM writes...

The guy was a friend of the odious Berezovsky, which further complicates things. Think of someone who is despised across the board in the USA, like Rumsfeld, starting to criticize the president and the CIA after 'retirement' and then defecting to Russia. Well, I guess Rumsfeld is responsible for combat deaths and not for cheating countless out of their savings via pyramid schemes.

Now Rumsfeld also owns a TV channel, and it carries a special news conference where some CIA agents get together and say that they have an order from the government to assassinate Rumsfeld, but they refuse to do so because it's not right, and that's why they are giving this nation-wide news conference on live TV on Rumsfeld's channel. Oh and by the way, the government is probably responsible for the poison order (after the defection of Rumsfeld to Russia). One of those agents is Litvinenko. Eight years later, after he sets up shop with Rumsfeld and becomes a business partner, he's poisoned and dies in Russia. You can see as to why I'm not that concerned.

That they (whoever the hell they are) wouldn't go after Berezovsky first is what's surprising. Although I'm sure Litvinenko probably knows more state secrets (than Rumsfeld-Berezovsky would in this case). Russians are already programmed to not overly like Jews too much. Berezovsky is giving way too many opportunities to them to hate our people even more.

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12. chemist on December 10, 2006 5:45 PM writes...


It was difficult to follow your message. I still don't see how a person who was living in the UK for 8 years may know any secrets at all. What secrets are you talking about?

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13. eugene on December 10, 2006 8:07 PM writes...

Yeah sorry, to be able to follow my message I guess you had to follow Russian news. I pretty much tried to summarize the story of Berezovskiy and Latvinenko in a few paragraphs, and it can't really be done that well.

As for someone who was living in the UK for 8 years not knowing any secrets, that is preposterous. Somebody who, let's use the example of the CIA, was a CIA agent for most of their life, then defected, is not going to know the names of other operatives, or how the CIA functions, where its secret prisons are, or its command structure? They aren't going to change everything just for one defector, even if he does start spilling it to MI5 five or six years down the road from the time of defection.

It would be much easier to kill him. If the person was hated back in the States, the Americans would accept his sudden death with no problems. The Brits would be up in arms about it (especially MI5 since they lost their source), and would not understand why the Americans are not indignant about the whole thing.

A little different though, Latvinenko is not that hated, but his friends Berezovski and Zakaev certainly are. Those two are definitely better targets for an assassination if it was to go spectacularly wrong. That's why this whole story is sorta fishy.

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14. chemist on December 12, 2006 1:50 PM writes...


This guy wasn't a spy. He did criminal investigation and was catching radioactive isotope smugglers (FBI rather than CIA analogy).

BTW, German police found the potential murderer. It was his business partner, an immigrant. It looks as they were trading the isotopes or running some business togeather.

If this information is true, I am never going to read a single british newspaper. I can watch an agent 007 tails in movie, I don't need to read the same ... in real life.

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15. eugene on December 12, 2006 4:21 PM writes...

If the guy wasn't a spy, then how come in 1998, he appeared on a TV newscast paid for by Berezovski, saying that he was ordered by the government and the secret service that he worked for (be it CIA or FBI analogy), to murder Berezovski?

If he wasn't a spy, then he was a liar and an opportunist out to make a buck and run away to England for an easy life.

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16. John on February 26, 2007 10:29 PM writes...

It is still legal to use phosphate fertilizers contaminated with Po-210 on tobacco. Because of the "furry" nature of the leaves, that is probably the worst plant on which to use such stuff.
Well, it's also the worst because the end cigarette product, one called just "tobacco" instead of Radioactive, Pesticide-Contaminated Tobacco, is about inhalation, thus sending the tiny rads to the furthest reaches of an ininformed, unwarned, unprotected, deceived victim's lungs.

To add injury to injury, many tobacco pesticides are chlorine chemicals which, when burned, produce dioxin in cigarette smoke (along with what's produced by burning the bleached cigarette paper and more pesticides from the many non-tobacco agricultural additives). I believe it is called The Promoter Effect whereby the dioxin accelerates the cell damage...the cancer...caused by the radiation. Not that dioxin isn't one of the worst carcinogens on its own.

(Though dioxin is easily the worst of the "Dirty Dozen" POPs slated for global phase-out by international treaty, in spite of wide concerns for "smoking and health", dioxin is still permitted in cigarette smoke, without a shred of warning, information, outrage, or legal challenges.)

With most research and most media and most gov't officials solidly in the hands of all sorts of chlorine and radiological industries (and their insurers and investors), its no wonder it is said that "little research has been done" etc.

Search the relevant terms for plenty. Look for the work of the late Edw. Martell on rads in cigarette smoke. Search up "pesticides tobacco"
"tobacco pesticides GAO", and even "dioxin in cigarette smoke".
Info is out there. Just ignored in order to a) save the perpetrators from liabilities, PR disasters and prosecution, and b) protect the careers of those who might, in a less oppressive time, otherwise do something positive for the sake of scientific and medical integrity, and humanity.

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17. The Coder on October 13, 2011 6:55 PM writes...

Derek, whats the best way to survive to a poison of Polonium (or its impossible)? Thanks!

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