New ways to make molybdenum-99

ONEFEAR raised by those who oppose Britain’s leaving the European Union without a deal is that the import of radioactive isotopes for medicine would be at risk. These short-lived substances might, people worry, encounter bureaucratic obstacles that slowed down their delivery and thus increased the fraction lost to radioactive decay.Particular concern surrounds molybdenum-99 (Mo), the workhorse of diagnostic nuclear-imaging. Mo, which has a half-life of just 66 hours, decays into a substance called technetium-99m (Tc) that has a half-life of six hours. Tc emits gamma rays, so its location in the body is easy to see using appropriate cameras. And it can be incorporated into a variety of chemicals, called radiopharmaceuticals, that accumulate preferentially in different bodily organs. This lets doctors observe what is going on in those organs. About 80% of diagnostic nuclear-imaging of this kind involves Tc, so without a continuous supply of Mo to make it from, this whole branch of medicine would grind to a halt.