An alternate title might be
Inject All You Want. We'll Make More!
Roger Z brought in a clipping about
account of a technetium-99m shortage.
My first thought on skimming this was "There's always a technetium-99m shortage. There's always going to be a technetium-99m shortage."
Technetium-99m has a six-hour half-life.
Alas, the news proves to be non-trivial. Hospitals obtain fresh technetium-99m from a supply of molybdenum-99, which has a 66-hour half-life, with 99mTc as a decay product. Make the molybdenum isotope in a reactor, transport it to hospitals, then "milk" fresh technetium from a solution containing 99Mo. This works for many days, then eventually fresh 99Mo is needed.
If the Chalk River reactor is down for a few days, no problem. If it's down for several weeks, trouble.