Producers deny blame for European radioisotope shortage

September 10, 2008

Industry sources blame a shortage of molybdenum-99 that is expected to frustrate nuclear medicine providers into mid-October on sheer bad luck, not a lack of cooperation between facilities.

Industry sources blame a shortage of molybdenum-99 that is expected to frustrate nuclear medicine providers into mid-October on sheer bad luck, not a lack of cooperation between facilities.

The three sites in Europe that generate Mo-99 coordinate their production and maintenance schedules so that at least one reactor is always online, according to Marc Gheeraert, president of the Association of Imaging Producers and Equipment Suppliers.

"When one reactor has a problem, there is usually backup. Here, many factors have been combined together," he said.

Problems began when a closure for technical inspection at the High Flux Reactor (HFR) in Petten, the Netherlands, had to be extended following the discovery of gas bubbles in the reactor's cooling system. This outage then overlapped with scheduled stoppages at Europe's other two Mo-99 producers.

The situation might not have been quite so bad if the inspection team had discovered the problem earlier. The last-minute discovery gave other Mo-99 producers little time to replan their own schedules.

"We saw this anomaly only a week before our stop was due to end," a spokesperson for the Nuclear Research and Consultancy Group that operates the Petten reactor told Diagnostic Imaging online.

Sites in Canada and South Africa that could have helped shore up the supply were initially unable to do so. An electrical storm had forced temporary closure of the NRU reactor at Chalk River in Ontario, while the Safari-1 reactor in Pelindaba, South Africa, was undergoing routine maintenance.

Contractual obligations to other clients make it difficult to alter production and maintenance cycles at short notice, said Bernard Ponsard, radioisotope production manager at the Belgian Nuclear Research Center in Mol, Belgium. The BR-2 reactor at Mol is a major supplier of doped silicon as well as radioisotopes. It also receives considerable funding for scientific research. Shutdowns are used to install the equipment needed for these applications.

European production of Mo-99, required to generate the medical isotope technetium-99m, could have halted earlier this summer if rival sites had not been willing to work together.

The BR-2 reactor was originally going to operate from July 21 until Aug. 18. This production schedule was moved back a week when managers were informed that the HFR would be closed for a technical inspection and core reload from July 28 to Aug. 24. If the BR-2 had stuck to its original plan, no European reactor would have been producing Mo-99 between Aug. 19 and Aug. 24.

"We have several meetings to correlate the reactors producing Mo-99 in Europe. We also have access to information on the operating periods of the Safari-1 reactor in South Africa and sometimes some information on the operation period of the NRU reactor in Canada," Ponsard said. "In the end, we even added an extra day and stopped the reactor on Aug. 26 instead of Aug. 25. We are flexible enough."

The BR-2 reactor is not likely to be back online until mid-October, and the HFR will be out of action until at least the end of October. Together, these two sites account for well over 90% of Europe's Mo-99 production.

"We are considering starting the BR-2 reactor one week early, on Oct.7, but it will be very difficult to satisfy that demand because of other activities that were scheduled a long time ago," Ponsard said.

Although the supply of Tc-99m has previously been good in Europe, radioisotope manufacturers should consider liaising more closely in the future to avoid similar problems, said Prof. Alan Perkins, a professor of medical physics at the University of Nottingham, U.K., and honorary secretary of the British Nuclear Medicine Society.

"Out of this I think will come more international cooperation and agreement about how the reactors are operated," he said.

For more information from the Diagnostic Imaging archives:

European nuclear medicine services respond to technetium supply crisis

Covidien advises customers about impending molybdenum shortage

Nuclear medicine braces for effects of Petten reactor shutdown