Europeans face potential Mo-99 supply nightmare; key nuclear reactor closed until February 2009

The Nuclear Research and Consultancy Group (NRG) has announced that the High Flux Reactor in Petten, the Netherlands, will remain shut down until Feb. 16, 2009, raising the possibility of another four months of molybdenum-99 shortages for thousands of European nuclear imaging services.

Most Mo-99 generated in Europe comes from two nuclear reactors: the HFR and the BR-2 reactor in Mol, Belgium. One of two plants in Europe that processes irradiated targets, the Institut des Radioéléments (IRE) in Fleurus, Belgium, has also been out of action.

The HFR and IRE facilities have been shut down since August for safety-related repairs. The BR-2 reactor halted operations at about the same time for routine maintenance and upgrades.

Mo-99 is the precursor isotope for the production of technetium-99m, a radionuclide used in about eight of 10 nuclear imaging procedures.

Radioisotope suppliers have drawn heavily on excess Mo-99 from the NRU reactor at Chalk River in Ontario, and the Safari-1 reactor in Pelindaba, South Africa, during this period. An agreement was also struck to allow radioisotope supplier Covidien to process material irradiated at the Osiris reactor in Saclay, France, at its own plant in Petten. This task is usually performed at the IRE.

"In this way for the past two weeks the only available reactor in Europe with production capacity has been coupled to the only available production line in Europe at the time. This has contributed significantly to limiting isotope shortages," according to an Oct. 14 statement from the NRG.

None of these backup strategies has been sufficient to make up the Mo-99 shortfall entirely. The supply of generators that produce Tc-99m from Mo-99 has fluctuated considerably through September and October, leading to imaging scheduling problems.

Many nuclear medicine departments were warned by suppliers in early October to expect a sizeable reduction in Tc-99m generator activity from Oct. 12 to 18 (week 42), owing to maintenance and refueling at reactor sites outside Europe.

But the supply situation has been less dire than expected. Providers received 65% to 70% of their normal deliveries of Mo-99 on Oct. 10, after being informed to expect less than 30%.

"The reactor in France produced remarkably more Mo-99 than expected," said Dr. J. Fred Verzijlbergen, nuclear medicine physician at the St Antonius Hospital in Nieuwegein, the Netherlands. "This means that week 42 will not be remembered as the expected nightmare."

Not all of the threatened supply problems for this week have been resolved, however. Some hospitals that usually receive a second Tc-99m generator shipment midweek have been advised that delivery will be delayed, possibly until Oct. 20.

"The problem is that we do not know when we will get the next supply or what will be the activity in this next shipment," said Dr. Serge Goldman, head of nuclear medicine at the ULB-Erasme Hospital in Brussels. "Since the crisis began, the shipments are not made following the usual schedule: the producers send what they can, when they can. So this week it is OK, but it remains difficult to schedule our examinations for the following weeks."

The full implication of today's announcement from the NRG has yet to be digested. In the short term, suppliers are predicting that Europe's Mo-99 shortage will ease considerably as material from the BR-2 reactor, scheduled to restart today, filters through the supply chain. This anticipated period of normality could be short-lived, however, with shortages predicted to again arise in November.

"It is our understanding that there will be another period of very limited availability of supply in November when several of the reactors in Europe are scheduled for maintenance at the same time," a spokesperson for Covidien said. "Our ability to supply Tc-99m generators to our customers will continue to be limited over the next few weeks, depending on the day of production and the availability of Mo-99 from the global reactors."

GE Healthcare has warned its customers that Tc-99m supply difficulties could continue while the HFR is offline. An open letter dated 1 Oct. posted on the British Nuclear Medicine Society website notes that until the Petten reactor restarts: "... there are still risks that we may not receive the full activity that we order, which could lead to a reduced offering or delayed service."

For additional information from the Diagnostic Imaging archive:

Producers deny blame for European radioisotope shortage

European nuclear medicine services respond to technetium supply crisis

Nuclear medicine braces for effects of Petten reactor shutdown