The Q & A strikes me as both accurate, and an extremely poor
explanation. Take the first question. "What is polonium?" He doesn't
bother to say it is a naturally occurring element that comes with
several isotopes, that it is always radioactive, that uranium is a
naturally occurring radioactive element, very widespread in small
concentrations, that U decays very slowly, and that the various
isotopes of polonium are indirect decay products of uranium, and thus
will always be found with natural uranium. For a much better
explanation, see the Wikipedia article on polonium and references there.
Incidentally, the Wikipedia article on depleted uranium, when I last
looked at it, seems very informative and more genuinely balanced than
many. Because Wikipedida can always be edited by readers, I suggest
looking at that article soon, and perhaps downloading it. I found one
of its references, a UN report on depleted uranium in Kosovo, also to
be helpful http://www.euro.who.int/document/e71919.pdf
Scientists are very often quite terrible at explaining things to the
public, or presumably even their students, partially because, as
here, they have no sense where to start. I am not sure whether even
the people on this list know even what I have assumed, such as what
is an element, or what are isotopes, and what are nuclei. Again
Wikipedia is a fairly extensive guide, though I was surprised to find
that the article on the nucleus could have been written fifty years
ago. This seems like an area that worthwhile SftP would devote some
energy to.
Best,
Michael
On Dec 3, 2006, at 7:55 PM, Phil Gasper wrote:
> http://www.nationalinterest.org/Article.aspx?id=13132
>
> Q&A on Polonium, the Poison Picked
>
> 11.30.2006
>
> Polonium-210 has been in the spotlight since it was identified as
> the poison that killed Alexander Litvinenko, a former officer in
> Russia's internal security service. Karl K. Turekian, professor of
> geology and geophysics at Yale University, explains its basic
> qualities, where and why it is produced and how it destroys human
> tissue. In an interview with National Interest online editor,
> Ximena Ortiz, Turekian also says that the decision to look for
> polonium as a source of the poisoning required a high-degree of
> sophistication and possibly some prior knowledge.
>
> NIo: Could you explain what polonium is?
>
> KKT: First of all, the basic chemistry of polonium: It's everywhere
> naturally. Polonium-210 occurs in anything that has uranium, but
> the levels are very, very low.
>
> During the development of the atomic bomb, what was needed was an
> initiator, something that would get the uranium-235 to start
> fissioning. They developed a way of manufacturing polonium-210
> artificially with bismuth-209. They took that polonium and combined
> it with beryllium. This emits neutrons at just the right energy to
> initiate a nuclear reaction. That's still the major use of
> polonium-210 now.
>
> When polonium-210 was fabricated in such large quantities-they
> would actually machine it and make shapes, and things like that-
> they also started using it for reactors in satellites. So there is
> that use to it as well.
>
> Anyhow, wherever there is a nuclear arsenal, there's polonium-210.
> It has a half-life of 138 days, which means if you start with ten
> grams, in 138 days it will be down to five grams and in another 138
> days it will be down to 2.5. It will be effectively gone in three
> and a half years. So they have to keep manufacturing it.
>
> NIo: Do all nuclear states manufacture polonium?
>
> KKT: Everyone uses polonium-210. People quickly realized they
> needed an initiator, and polonium-210 is the initiator of choice
> for a lot of reasons.
>
> NIo: Does it make a difference if you manufacture a uranium bomb
> versus a plutonium bomb?
>
> KKT: All of them need something to provide neutrons to initiate the
> reaction.
>
> NIo: Would civilian nuclear reactors also use polonium?
>
> KKT: My guess is that polonium-210 is not necessary for a nuclear
> reactor for energy production, though I'm not an expert in that
> area. It's actually manufactured from bismuth in nuclear reactors.
> Whereas bombs in their compact state-with a core of plutonium-210
> and beryllium-are dependent on it.
>
> NIo: So you wouldn't be producing it if you're not producing a bomb?
>
> KKT: Probably not.
>
> NIo: Once you obtained polonium-210, how would you use it as a poison?
>
> KKT: Polonium-210 is called an alpha emitter. Alpha is essentially
> a helium atom stripped of all its electrons, and it comes out with
> a tremendous amount of energy. It does not have a long range,
> however; you can put a piece of paper over it and it stops the
> particles. They do a lot of damage close up, but they don't go
> great distances. You could carry it around in a box, and no one
> would know you had any by the radiation. It would get warm if you
> had a lot of it, but no one could detect it if you had a vial
> surrounded by sawdust.
>
> That's also the source of its hazards. Being an alpha emitter, with
> these very energetic, charged particles, if it bombards tissue it
> destroys the tissue, or causes it to mutate. People have been
> studying that for quite awhile, for a lot of reasons including the
> hazards of second-hand smoke. It has an interesting history. A
> massive dose of alpha particles next to human tissue would cause
> damage that could lead to sickness and death.
>
> NIo: How could one use it as a poison without hurting themselves?
>
> KKT: Remember the rays aren't like X-rays or gamma rays that
> penetrate a great distance. This stuff, the radiation isn't going
> to go beyond the cardboard box. It's easy to handle as long as
> there's a container.
>
> NIo: What about removing it, how would you poison another person?
> Would you put it into food?
>
> KKT: Well, you could put it into food. It would act like a small
> explosion in the cells, and that's where the damage is done. It
> could also be inhaled, but I don't think that's what you would do
> to someone else. You're not going to use an aerosol spray in the
> air you're breathing.
>
> NIo: How would you go about exposing the food to the polonium?
>
> KKT: I'm not really a chef. You don't need a whole lot of it,
> though; adding it to food in some way or another need not be
> obvious or ostentatious.
>
> NIo: It still seems like such an exotic property to choose, though.
>
> KKT: Well, there's plenty of polonium-210 available-any place
> there's a bomb maintenance facility-and it's always manufactured.
> It is a sophisticated thing to know that polonium-210 is dangerous,
> but that's been known because it did a lot of harm to people
> throughout the Manhattan Project.
> Beyond that, I have no idea. I was surprised that somebody was
> clever enough to look for polonium-210 during the investigation. If
> you were looking for alpha emitters, there is a diagnostic energy
> for polonium-210 no one would mistake. But the act of looking into
> that shows some insight into what might have been used, and I have
> no idea how they got that insight. Maybe they knew something about
> this person or the people he hung around with.
>
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