Ultima Thule

In ancient times the northernmost region of the habitable world - hence, any distant, unknown or mysterious land.

Monday, December 11, 2006

Polonium 210

By Aussiegirl

An article on the history and relative ubiquity of polonium 210. Polonium was of course discovered by Marie Curie in 1898 and named after her native Poland.
Accompanying this photograph of Pierre and Marie was this charming and sweet excerpt of a letter that Pierre wrote to Marie exploring the possibility of marriage:

“We have promised each other (is it not true?) to have, the one for the other, at least a great affection. Provided that you do not change your mind! For there are no promises which hold; these are things that do not admit of compulsion.

“It would, nevertheless, be a beautiful thing in which I hardly dare believe, to pass through life together hypnotized in our dreams: your dream for your country; our dream for humanity; our dream for science. Of all these dreams, I believe the last, alone, is legitimate. I mean to say by this that we are powerless to change the social order. Even if this were not true we should not know what to do.... From the point of view of science, on the contrary, we can pretend to accomplish something. The territory here is more solid and obvious, and however small it is, it is truly in our possession.”

Polonium - Alexander V. Litvinenko - Vladimir V. Putin - New York Times

Published: December 3, 2006

THE trail of clues in the mysterious death of Alexander V. Litvinenko may lead to Moscow, as the former spy claimed on his deathbed. But solving the nuclear whodunit may prove harder than Scotland Yard and many scientists at first anticipated.

The complicating factor is the relative ubiquity of polonium 210, the highly radioactive substance found in Mr. Litvinenko’s body and now in high levels in the body of an Italian associate, who has been hospitalized in London. Experts initially called it quite rare, with some claiming that only the Kremlin had the wherewithal to administer a lethal dose. But public and private inquiries have shown that it proliferated quite widely during the nuclear era, of late as an industrial commodity.

“You can get it all over the place,” said William Happer, a physicist at Princeton who has advised the United States government on nuclear forensics. “And it’s a terrible way to go.”

Today, polonium 210 can show up in everything from atom bombs, to antistatic brushes to cigarette smoke, though in the last case only minute quantities are involved. Iran made relatively large amounts of polonium 210 in what some experts call a secret effort to develop nuclear arms, and North Korea probably used it to trigger its recent nuclear blast.

Commercially, Web sites and companies sell many products based on polonium 210, with labels warning of health dangers. By some estimates, a lethal dose might cost as little as $22.50, plus tax. “Radiation from polonium is dangerous if the solid material is ingested or inhaled,” warns the label of an antistatic brush. “Keep away from children.”

Peter D. Zimmerman, a professor in the war studies department of King’s College, London, said the many industrial uses of polonium 210 threatened to complicate efforts at solving the Litvinenko case. “It’s a great Agatha Christie novel,” he said. “She couldn’t have written anything weirder than this.” [....]

As in any good murder mystery, the deadliness was foreshadowed. Marie Curie, who discovered the radioactive element in 1898 and named it after her native Poland, organized its close study. One of her polonium workers died in 1927 from apparent poisoning, according to Susan Quinn, author of “Marie Curie: A Life” (Simon & Schuster, 1995). Another worker lost her hair.

At first, mines provided minute samples nearly invisible to the human eye. But the debut of nuclear reactors let scientists make polonium 210 by the pound. The substance emits swarms of subatomic rays, and the Manhattan Project in 1945 used them to trigger the world’s first atom bombs. Such initiators became the global standard for basic nuclear arms.

President Eisenhower, eager to promote “atoms for peace,” had the high heats of polonium 210 turned into electricity for satellites. But the batteries lost power relatively fast because of the material’s short half-life, just 138 days. The United States made few such spacecraft.

By the 1960’s, researchers worried increasingly about polonium 210’s deadly health effects. Harvard researchers found it in cigarette smoke and argued that its concentrations were high enough to make its radioactivity a contributing factor in lung cancer.

Vilma R. Hunt, who helped lead the studies, called polonium 210 a nightmare for health workers, and perhaps sleuths, because it tended to move about in unexpected ways. “It crawls the walls,” she said in an interview. “It can be lost for a while and then come back.”

Though dangerous when breathed, injected or ingested, the material is harmless outside the human body. Skin or paper can stop its rays cold.

Industrial companies found polonium 210 to be ideal for making static eliminators that remove dust from film, lenses and laboratory balances, as well as paper and textile plants. Its rays produce an electric charge on nearby air. Bits of dust with static attract the charged air, which neutralizes them. Once free of static, the dust is easy to blow or brush away. [....]

An antistatic fan made by NRD, of Grand Island, N.Y., contains 31,500 microcuries of polonium 210 — or, in theory, more than 10 lethal doses. The unit often sells commercially for $225.00. Repeated calls to NRD were not returned, but the company in sales literature describes its products as unusually safe.

The company’s antistatic brushes contain less polonium, typically 500 microcuries of radiation. The three-inch brush often sells on the Web for $33.99. In theory, by spending $203.94, before tax and any handling charges, and then disassembling six brushes, someone with lab experience could accumulate a lethal dose.

In Tennessee, the Oak Ridge National Laboratory sells dozens of types of rare nuclear materials to American manufacturers. But Bill Cabage, a lab spokesman, said it sold no polonium 210 because Russia was able to do so much more inexpensively.

“That’s typical” of exotic radioisotopes, he said. “We can’t compete with their prices.” [....]

Still, several experts held out the possibility that close examination of polonium 210 residues from Mr. Litvinenko’s body or from the multiple sites where it has been found around London might reveal nuclear fingerprints that could throw light on the baffling case.

“What they’ll be looking for is radioactive contaminants made at the same time,” said Dr. Happer of Princeton. “They’ll do the best they can technically,” hoping to find a match between the London samples and the known attributes of the world’s stocks of polonium 210. “But my guess,” he added, “is that it will take an informant” to clear up the mystery.


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