The NRU reactor at
Chalk River is offline till 2010

Canadian Isotope Reactor to Be Shuttered Until Next Year

August 14, 2009
by Lynn Shapiro, Writer
Dealing a blow to downstream suppliers and to the medical community alike, the Atomic Energy of Canada Limited (AECL) said it will not reopen its National Research Universal (NRU) reactor in Chalk River, Ontario until the first quarter of 2010, as a result of repairs that forced the 52-year-old plant to shut down in May.

Since AECL produces approximately 40 to 50 percent of medical isotopes used in North America, the extended shutdown has suppliers scrambling for new sources.

In July, AECL said that the generator would be back online by late 2009. AECL shuttered the 52-year-old reactor in May, after a leak was found in the reactor's vessel.

The plant is the only one in North America, and one of five in the world, that makes molybdenum-99, which decays to become technetium-99m, an isotope used in an increasing number of medical imaging tests.

Michael Graham, PhD, SNM's President, and director of nuclear medicine at the University of Iowa, commenting on the shortage, told DOTmed News in June that "the bottom line is that patients needing nuclear medicine tests may not get them, and may even have to undergo exploratory surgery in some cases."

He noted radioisotopes are used for such tests as: looking at blood flow in the heart; for bone scans, and for many other studies, like lung scans and uptake of excretion in the kidneys.

Nine Sites Need Repair

AECL said in a statement that it the agency is dedicated to reopening its reactor as soon as possible, but that "detailed analysis of .... data collected confirms nine sites likely requiring repair. AECL says that high resolution scanning data available recently has identified both wall thinning and localized pitting that suggests different corrosion effects.

"This data points to the need to better understand the nature of the corrosion mechanism," the agency says. "As a result, AECL is considering further testing by taking samples from the vessel wall in order to provide more comprehensive data. Third party corrosion experts have been consulted and will provide feedback," the agency says.

Weld Build-up Technique

The AECL says that it is considering applying a technology known as the "weld build-up technique" over a broader area or band at the inside base of the reactor vessel wall, which will address all nine of the sites that have been identified. "In view of the number and locations of the repair sites, the band weld build-up application may be a more efficient and durable way to proceed in repairing the reactor vessel."

Alternative Technique

Meanwhile, AECL continues to pursue a second mechanical repair technique, in order to address conditions not conducive to band weld repair. "Both techniques are being advanced simultaneously to provide assurance that the appropriate repair technique is available when needed," the agency says.

AECL notes that "guidance on the duration of the shutdown continues to be founded on the best evidence available, including the most up-to-date analysis of the inspection data, progress on repair strategies, and critical path requirements for restart after an extended shutdown. At this time, the application of the band weld build-up technique, and the increased number of sites, indicates the NRU will return to service during the first quarter of 2010. Further guidance on a return to service date will be provided when more data is available," AECL says.

The agency concludes that "there is no threat to workers, the public, the environment or nuclear safety related to this event." More information on the repair and status updates on the NRU is available at

Lantheus Scrambles to Find Suppliers

Responding to the extended shutdown of its major supplier, Lantheus Medical Imaging's President and CEO, Don Kiepert, said on Friday that the company "continues to collaborate with its supply partners and key customers to address the ongoing global isotope shortage of molybdenum-99 (Mo-99), the parent isotope of technetium-99m (Tc-99m), as a result of the prolonged NRU reactor shutdown in Canada and the current shutdown of the High Flux Reactor (HFR) in the Netherlands [expected to be reopened this month].

"Recently, the company announced new Mo-99 supply agreements with NTP Radioisotopes (Pty) Ltd., a subsidiary of the Nuclear Energy Corporation of South Africa (NECSA), the National Institute for Radioelements (IRE), Belgium, and the Australian Nuclear Science and Technology Organisation (ANSTO) as a supplier for low-enriched uranium (LEU) Mo-99 in the North America, to manufacture and supply us with an ongoing volume of Mo-99. These agreements demonstrate our continued commitment to investing in a supply chain diversification strategy to address the limited and fragile global Mo-99 supply chain," Kiepert says.

Meanwhile, Lantheus says it has significantly increased production of Thallium 201 in its cyclotrons on site which are operating at full capacity to meet the demand for this alternate cardiac imaging agent during the Mo-99 shortage.

"As part of our commitment," Kiepert says, "we have recently endorsed the American Medical Isotopes Production Act sponsored by Representatives Edward J. Markey (D-Mass.), chairman of the House Energy and Commerce Committee Subcommittee on Energy and the Environment, and Fred Upton (R-Mich.), the ranking member of the Subcommittee, which seeks to ensure that a reliable supply of critical medical isotopes is produced in the United States as soon as possible," Kiepert says.

Read More on DOTmed

Related DOTmed News reports about the 56th SNM annual meeting, the radiopharmaceutical shortage, and nuclear medicine topics:

Industry Sector Report: Nuclear Medicine, DOTmed Business News, June 2009, now online

SNM and Coalition of Professional Organizations Call for Action on Ongoing Medical Isotope Shortage

NRU Idled Longer Than Expected; Lantheus Gets FDA Nod for LEU

New Research and Isotope Update From SNM

MO-99 Suppliers Find New Sources

PETNET Prepared to Address NaF Production Shortages

SNM Outgoing President Robert Atcher Discusses Isotope Supply and Molecular Imaging

Canadian Health Minister and SNM Leaders Meet in Toronto

Medical Isotope Shortage Reaching Crisis Proportions

SNM Past President Alexander J. (Sandy) McEwan Named Special Advisor to Canada's Minister of Health

Lantheus Medical Imaging Takes Steps on Mo-99 Shortage

MDS Nordion Opens New Radiopharmaceutical Production Facility in Belgium

An Interview With Henry Wagner, M.D.

Serious Concerns as Isotope Shortage Looms

Canada Stops Medical Isotope Reactor Project