Canada’s National Research Universal (NRU) reactor appears days away from coming back on-line – a move that should temporarily alleviate a shortage of medical isotopes that has plagued clinicians for more than a year.
The Canadian Nuclear Safety Commission gave its approval July 7 to restart the NRU reactor, with loading of molybdenum targets and reactor fuel set to begin within the next week.
“We are still tracking to be in isotope production by the end of July,” said Dale Coffin, director of corporate communications for Atomic Energy of Canada Ltd., which operates the reactor.
Molybdenum-99 (Mo-99) and its decay product, technetium-99m, the most widely used medical radioisotope, have been in short supply in recent years, with just five multipurpose research reactors supplying more than 95% of the world’s supply of Mo-99.
Before it shutdown in May 2009, the NRU in Chalk River, Ontario, produced roughly 30% of the global supply of medical isotopes and 50% of the United States’ supply, Mr. Coffin said.
Holland’s Petten reactor was taken out of service most recently in February 2010, and is anticipated to be restarted sometime next month.
The shutdown of the two reactors has forced clinicians across the globe to ration available isotope materials, reschedule nuclear imaging procedures and find alternative ways of diagnosing patients.
According to a survey released last month by the Canadian Institute for Health Information, the number of cardiac, bone and lung diagnostic tests on Canadian patients decreased 22% in October 2009, compared with October 2008. This represents about 12,000 fewer exams over this period. The drop in nuclear exams ranged from highs of 18% for lung perfusion and bone exams to 25% for cardiac tests.
The resumption of operations at NRU will alleviate the shortage of Mo-99 and other reactor produced isotopes, and keep the U.S. market from experiencing the issues of transportation delays from sites in Europe and South Africa, said Robert Atcher, Ph.D., with the Los Alamos National Laboratory, past president of the Society of Nuclear Medicine and chair of its isotope task force.
It will not, however, resolve the long-term problem of maintaining a consistent supply to the medical and veterinary communities.
“All the reactors that are currently providing material to the U.S. market are approaching 50 years of age; they can’t be expected to operate forever,” Dr. Atcher said. “More to the point, the Canadian government has made it clear that they no longer believe that they should serve the world market with isotopes.”
He noted that the government decided not to replace the NRU with another multi-purpose nuclear reactor, despite the recommendation of an expert panel it commissioned to examine the problem. In addition, the government is focusing its research funding on potential solutions to the problem that will only provide material for the Canadian market, a move Dr. Atcher said was reinforced at a meeting last month of the High Level Group on the Security of Supply of Medical Radioisotopes.
“There is no question that we need to develop alternative production capacity to supply the U.S. market, which represents 50% of the world demand for Mo-99,” he said.
– Patrice Wendling (on Twitter @pwendl)