Readers of this blog (are there any?) may recall two earlier entries on December 14, 2007 and the May 23, 2008, when I discussed a shortage of technetium for medical imaging. It seems that this problem just won’t go away. According to a recent article in the New York Times, we are once again experiencing a global shortage of technetium, caused by the shutdown of nuclear reactors in Canada and the Netherlands. I fear that although the current shortage may be temporary, disruptions of the supply of technetium will reoccur with increasing frequency as nuclear power plants age. A reactor dedicated to technetium production in the United States would go a long way toward solving the problem, but would be expensive.
Russ Hobbie and I discussed technetium in the 4th edition of Intermediate Physics for Medicine and Biology. Technetium-99m—the key isotope of technetium for medical imaging—is a decay product of molybdenum-99, which in turn is a nuclear fragment that is produced during the fission of uranium. It is widely used in part because its 140 keV gamma emission and its 6 hour half life are particularly suited to nuclear medicine diagnostic procedures. 99mTc is often combined with other molecules to make radiopharmaceuticals, such as 99mTc-sestamibi and 99mTc-tetrofosmin, that can have very specific effects as tracers. For more about the discovery of technetium, see the March 13, 2009 entry of this blog.
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