[The reactor] produces about 20% of the world's supply of technetium; the rest comes from six other aging reactors in Europe, Australia and South Africa. These reactors bombard highly-enriched uranium targets to produce molybdenum-99, which decays into technetium. Stockpiling the radioisotopes is impossible because of their short half-lives — 66 hours for molybdenum-99, and six [hours] for technetium-99m. As a result, supply disruptions can quickly translate into shortages at hospitals, as happened when two reactors shut down for repairs and maintenance in 2009.
One of the most common medical uses for technetium is single-photo emission computed tomography (SPECT), which can be used to monitor blood flow in the heart and brain and scan bones for tumours.
[...] The United States currently provides the bulk of the world's [highly-enriched uranium] targets but plans to halt shipments of highly enriched uranium by 2020. However, Russia has indicated that it may begin production of molybdenum-99 in the future, and has not yet committed to using [low-enriched uranium] targets.
http://www.nature.com/news/reactor-shutdown-threatens-world-s-medical-isotope-supply-1.20577
https://en.wikipedia.org/wiki/Single-photon_emission_computed_tomography
(Score: 2) by butthurt on Tuesday September 13 2016, @11:25PM
I looked at two earlier Nature articles, from 2012 and 2013. They explain that 99mTc could in theory be made by using particle accelerators instead of nuclear reactors and that efforts to do so had begun.
http://www.nature.com/doifinder/10.1038/504202a [nature.com]
http://www.nature.com/doifinder/10.1038/nature.2012.10064 [nature.com]