Nuclear Weapons

Finally, Some Sense About Uranium and Dirty Bombs

03.21.08 | 3 min read | Text by Ivan Oelrich

The Columbian military recently raided FARC camps just across their borders. The Columbians confiscated lap top computers containing emails between the FARC and dealers offering to sell them explosives, which the emails suggested included uranium that the dealer was willing to sell for about one million dollars a pound. The press has several times bit on these types stories, sensationalizing them and getting the science all wrong.

There seems to be a widespread idea that uranium can be used for nuclear weapons. Well, it can. That is, one isotope of uranium can be, but natural uranium is less than 1% of that isotope and enriching it is a daunting technical challenge. (Many chemical elements have more than one isotope, atoms that have identical chemical properties but slightly different weights.) Since uranium can power nuclear weapons and nuclear bombs, it must be highly radioactive and could at least be used as a dirty bomb, right? Wrong, but you would never know by reading most such stories in the newspapers. So it is refreshing to read a story that gets it right and is properly skeptical. Kelly Hearn of The Washington Times has written that piece.

Since uranium is available on the spot market for about $70 per pound, the asking price of a million a pound should raise suspicions. This price might be justified if the uranium were enriched, that is, mostly uranium-235. If the uranium were enriched, it would be a huge story. I find it very difficult to imagine how a non-state terrorist organization could enrich natural uranium; the technology and manufacturing are simply too much. If a terrorist group could, however, get hold of sufficient quantities of uranium-235, then I can easily imagine how they could construct the simplest possible nuclear bomb that would have an explosive force equal to a few thousand tons of TNT. Exploding such a bomb in a major city would make every past terrorist attack pale. Given the consequences, any possibly, even a remote possibility, that terrorists might have got hold of enriched uranium should be taken seriously and investigated.

But many related past newspaper articles have been weak on several points: they are vague on the important differences between uranium and enriched uranium; they incorrectly assert or imply that, even if not useful for a nuclear bomb, then uranium could be used to make a dirty bomb; and they are insufficiently skeptical of these reports, failing to put them into context by explaining how common uranium and dirty bomb scams are. Most recently, there was a flurry of articles about the supposed highly enriched uranium that was found in Slovakia. The story did not make sense from the beginning and most of the science in the press coverage was, at best, muddled if not flatly wrong. Notice that that story has totally disappeared. I asked a couple of the reporters who wrote about it what had happened and they tell me that the Slovak police simply stopped talking about it. Perhaps because they had some big case but my guess is because they realized they had misspoken early on. So I welcome Hearn’s article. The story really is not so much about this one case in Columbia but about the need to be cautious in all such cases. Certainly, loose enriched uranium is something to worry about, but we need to keep our heads, not sensationalize, and get the science straight if we are to have any hope of making good decisions.


Update on 27 March 2008: Interesting story in the Miami Herald. The Columbians have found 20 kg of uranium that is described as “impoverished” in the story. I assume this means it is depleted uranium, that is, uranium that actually has a lower concentration of the important U-235 than does natural uranium. Depleted uranium is widely available.

 Update on 28 March:  Another good story from the AP’s Frank Bajak.