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NRU could be up and running soon
By Hamish Johnston
The shortage of medical isotopes caused by the year-long shutdown of Canada’s NRU reactor could soon be over.
Atomic Energy of Canada (AECL) – which operates the 53-year-old facility in Chalk River, Ontario – will appear before the Canadian Nuclear Safety Commission on 28 June to ask permission to restart the reactor.
If it gets the thumbs up, AECL says that isotope production could resume by the end of July.
Over the past few years the supply of Mo-99, which is used to make the medical isotope Tc-99m, has been threatened by two safety-related shutdowns of the ageing reactor. Normally, NRU supplies North America with Tc-99m and accounts for a significant chunk of world production.
The first shutdown began in December 2007 and lasted one month. The second started in May 2009 and is ongoing.
You can read more about how AECL plans to restart NRU here .
These are good news indeed, but the lengthy sutdown of the NRU, and the more recent maintenance shutdown of the HFR reactor at Petten (The Netherlands), are a serious call of attention regarding the dependability on so few sources of Mo-99. The MAPLE reactors project in Canada was scrapped after they turned out to show positive reactivity coefficient, and there seems no be no interest in redesigning them. The problem is apparently solved for the time being, but a long term solution is badly needed, specially when the availability of highly enriched U-235 targets, needed for Mo-99 production, will be restricted, due to the nuclear security reasons. Maybe a net of cyclotrons, appropriately distributed, might be a safe way of providing Tc-99m.