A nine-month investigation by Al Jazeera discovered rare, radioactive
polonium on the ex-Palestinian leader's final belongings. The finding
suggests that Arafat was poisoned with polonium, a rare, highly
radioactive element. The polonium was found in blood, sweat, urine and
saliva stains on his personal effects, and the levels recorded by
forensic pathologists in Switzerland - who studied the items - do not
occur naturally. Al Jazeera's Clayton Swisher reports.
(CNN) -- Did Yasser Arafat die eight years ago of natural causes or was the 75-year-old Palestinian leader poisoned, as his widow believes?
That's the question forensic investigators from at least three nations are trying to answer by testing samples taken from Arafat's body, which was exhumed Tuesday and reburied a short time later.
Tests are being performed on those samples for the presence of polonium -- a toxic, radioactive element found on some of his personal belongings earlier this year.
For five decades, Arafat was the most prominent face of Palestinian opposition to Israel, first as the head of the Palestine Liberation Organization, which carried out attacks against Israeli targets, and later as the head of the Palestinian Authority.
The Palestinian Authority, which runs the West Bank, says it is convinced Israel is behind any poisoning of Arafat.
"We had nothing to do with it," Israeli government spokesman Mark Regev told CNN's Wolf Blitzer. "Those charges are ludicrous and it's conspiracy theories which, as you know, sometimes have legs of their own. But, as you know, there is no truth in it whatsoever." more
Yasser Arafat and the Mysteries of Polonium-210
- November 27, 2012
I first wrote about Yasser Arafat and polonium-210 this summer when traces of the radioactive element were found in the personal effects of the dead former Palestinian leader. As his body was exhumedearlier today to look for more conclusive evidence of poisoning, the following is an update of that post.
In the late 19th century, a then-unknown chemistry student named Marie Curie was searching for a thesis subject. With encouragement from her husband, Pierre, she decided to study the strange energy released by uranium ores, a sizzle of power far greater than uranium alone could explain.
The results of that study are today among the most famous in the history of science. The Curies discovered not one but two new radioactive elements in their slurry of material (and Marie invented the word radioactivity to help explain them). One was the glowing element radium. The other, which burned brighter and briefer, she named after her home country of Poland — Polonium (from the Latin root,polonia). In honor of that discovery, the Curies shared the 1903 Nobel Prize in physics with their French colleague Henri Becquerel for his work with uranium.
Radium was always Marie Curie’s first love – “radium, my beautiful radium,” she used to call it. Her continued focus gained her a second Nobel Prize in chemistry in 1911. (Her Nobel lecture was titledRadium and New Concepts in Chemistry.) It was also the higher-profile radium — embraced in a host of medical, industrial, and military uses — that first called attention to the health risks of radioactive elements. I’ve told some of that story here before in a look at the deaths and illnesses suffered by the “Radium Girls,” young women who in the 1920s painted watch-dial faces with radium-based luminous paint.
Polonium remained the unstable, mostly ignored step-child element of the story, less famous, less interesting, less useful than Curie’s beautiful radium. Until the last few years, that is. Until the reported 2006 assassination by polonium 210 of Russian spy turned dissident, Alexander Litveninko. And until the news, first reported by Al Jazeera in July, that a Swiss laboratory had detected surprisingly high levels of polonium-210 in the clothes and other effects of the late Palestinian leader Yasser Arafat.
Arafat, 75, had been held for almost two years under an Israeli form of house arrest when he died in 2004 of a sudden wasting illness. His rapid deterioration led to awelter of conspiracy theories that he’d been poisoned, some accusing his political rivals and many more accusing Israel, which has steadfastly denied any such plot.
Recently (and for undisclosed reasons) his widow agreed to the forensic analysis of articles including clothes, a toothbrush, bed sheets, and his favorite kaffiyeh. Al Jazeera arranged for the analysis and took the materials to Europe for further study. After the University of Lausanne’s Institute of Radiation Physics released the findings, Suha Arafat asked that her husband’s body be exhumed and tested for polonium.
The exhumation was authorized by Mahmoud Abbas, president of the Palestinian Authority, and that order was carried out this morning. Reportedly 20 tissue samples were taken from the eight-year-old remains and will be turned over to independent laboratories in France, Switzerland, and Russia.According to The Washington Post, the laboratories are expected to include a broader toxicology analysis as well. Results are not expected for several months.
And at this point, as we anticipate those results, it’s worth asking some questions about polonium-210 and about the mysteries surrounding this particular death. We might starting with wondering why a killer would pick a poison that might leave a trail of evidence behind. In the case of the Radium Girls, scientists found that their bones were still hissing with radiation years after their deaths. In the case of Litvinenko, public-health investigators found that he’d literally left a trail of radioactive residues across London where he was living at the time of his death.
But this story is different and most of that has to do with time – and timing. Radium has a half-life of about 1,600 years. But polonium-210 is far less stable; it has a half-life of 138 days. Half-life refers to the time it takes for a radioactive element to burn through its energy supply, essentially the time it takes for activity to decrease by half. For comparison, the half life of the uranium isotope U-235, which often features in weapon design, is 700 million years. In other words, polonium is a little blast furnace of radioactive energy.
To understand that difference, it helps to begin by stepping back to some of the details provided in the Curies’ seminal work. Both radium and polonium are links in a chain of radioactive decay (element changes due to particle emission) that begins with uranium. Polonium, which eventually decays to an isotope of lead, is one of the more unstable points in this chain, unstable enough that there are some 33 known variants (isotopes) of the element. The speed of its decay means that eight years after Arafat’s death, it would probably be identified by the its breakdown products rather than the direct radioactive evidence associated with more recent fatalities. And still, the breakdown products remain interesting – and possibly traceable - as an assassin’s weapon.
Like radium, polonium’s radiation is primarily in the form of alpha rays — the emission of alpha particles. Compared to other subatomic particles, alpha particles tend to be high-energy and high-mass. Their relatively larger mass means that they don’t penetrate as well as other forms of radiation; in fact, alpha particles barely penetrate the skin. And they can stopped from even that by a piece of paper or protective clothing.
That may make them sound safe. It shouldn’t. It should just alert us that these are only really dangerous when they are inside the body. If a material emitting alpha radiation is swallowed or inhaled, there’s nothing benign about it. Scientists realized, for instance, that the reason the Radium Girls died of radiation poisoning was because they were lip-pointing their paintbrushes and swallowing radium-laced paint. The radioactive material deposited in their bones — which literally crumbled. Radium, by the way, has a half-life of about 1,600 years. Which means that it’s not in polonium’s league as an alpha emitter. How bad is this? By mass, polonium-210 is considered to be about 250,000 times more poisonous than hydrogen cyanide. Toxicologists estimate that an amount the size of a grain of salt could be fatal to the average adult.
In other words, a victim would never taste a lethal dose in food or drink. In the case of Litvinenko, investigators believed that he received his dose of polonium-210 in a cup of tea, dosed during a meeting with two Russian agents. (Just as an aside, alpha particles tend not to set off radiation detectors so it’s relatively easy to smuggle from country to country.) Another assassin advantage is that illness comes on gradually, making it hard to pinpoint the event. Yet another advantage is that polonium poisoning is so rare that it’s not part of a standard toxicology screen. In Litvinenko’s case, the poison wasn’t identified until shortly after his death. In Arafat’s case — if polonium-210 killed him and that has not been established — obviously it wasn’t considered at the time. And finally, it gets the job done. “Once absorbed,” notes the U.S. Regulatory Commission, “The alpha radiation can rapidly destroy major organs, DNA and the immune system.”
Many Palestinians have long suggested that Israel is behind Arafat’s death – an accusation that country has repeatedly denied, pointing out that it had nothing to gain from his death. But the presence of polonium intensifies that assassination issue. Why?
One obvious reason is that polonium-210 is not very readily available to the average citizen. It’s a rare element. And a rare industrial product. About 100 grams are produced worldwide annually — and production is both limited and controlled. For instance, the NRC licenses polonium-210 for use in certain static-elimination devices in industry. But the amount allowed is so small that the agency estimates that it would take 30,000 devices to assemble a lethal dose.
The element is most commonly produced through neutron bombardment in nuclear reactors, which again suggests that it’s a product available to a chosen few. Which brings me to an assassin disadvantage — traceability. In the case of the Litvinenko killing, investigators suggested that the polonium isotope found in his body had a chemical signature that indicated production in a Russian nuclear reactor. Such clues, according to Al Jazeera, would be sought in analyzing Arafat’s body: “A conclusive finding that Arafat was poisoned with polonium would not, of course, explained who killed him,” the story concludes. “It is a difficult element to produce, though — it requires a nuclear reactor — and the signature of the polonium in Arafat’s bones could provide some insight about its origin.”
As Patrick Walter points out in an excellent analysis in Chemistry World (published by the Royal Society of Chemistry) modern instruments are capable of detecting polonium breakdown products in incredibly small amounts, even the bare trace that might be found here. But as he also notes, the picture is still complicated. Polonium-210 is, after all, a naturally occurring element and finding evidence of exposure doesn’t necessarily mean evidence of foul play.
And as forensics experts emphasized to the BBC, the years of polonium decay may yet make precise identification of the source impossible. Further, the decay of the body itself is likely to render a clear cause of death portrait equally difficult. As one forensic pathologist noted: ”Trying to interpret what levels of radiation there would have been eight years ago and whether [they were] sufficient to be fatal is going to be very, very difficult.”
Realistically, even if the tests are inconclusive, suspicion will remain. And even if this really were a polonium murder — or let’s say a heartless, government-sanctioned killing — forensics still won’t give away the name of the killer or necessarily the country. But there is that slim possibility that tests could reveal the source of the poison and, as a side-effect, the home of the assassin. It’s that latter whisper of a possibility that makes these eventual results so tantalizing – and, I’d add, a little unnerving.
Images: 1) Pierre and Marie Curie: Wikipedia 2) Yasser Arafat: Hans Jørn Storgaard Andersen/Wikimedia Commons
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