Minister of Natural Resources Lisa Raitt acknowledged Thursday the global supply of medical isotopes for diagnostic tests is tenuous due to the shutdown of Canada's Chalk River reactor, the world's biggest supplier of isotopes.
The minister met with an international group of isotope experts in Toronto to discuss short-term supply concerns.
Raitt said other nuclear facilities in the Netherlands, South Africa, Belgium and France are making up for the shortfall, but only just.
"Even with Canada down the total global demand for medical isotopes is met by those other four reactors, the question is having them work together," Raitt said, but then warned "should one of the reactors be down, the total global supply will not be met."
Chalk River's NRU reactor was shut down in mid-May, and is expected to be out of commission for three months or longer.
It supplies up to 40 per cent of the global demand, and 50 per cent of the North American demand.
Canadian-produced isotopes are used in 50,000 medical procedures a day, 10 per cent of those here in Canada.
Raitt acknowledged that managing the global supply is "very difficult knowing that the Canadian reactor plays such a big part in the global supply chain."
The minister reiterated that the repair of Chalk River is the top priority for the nuclear agency, AECL.
"The government has made it very clear to AECL that this is their priority, and getting Chalk River's reactor up and running safely and producing medical isotopes is the most important thing they can be doing right now," Raitt said.
Raitt said repair work on the 52-year-old reactor has been slow going, but safety, not speed, is of the essence.
"They are using techniques to visually inspect the leak, find where the leak is, and then from there they'll devise ways in which to repair the leak and report out to the Canadian public," Raitt said.
The taskforce on the Security of Supply of Medical Radio Isotopes was established by the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD). The group has met twice already since January, even before the Chalk River shutdown moved the shortage problem into a full crisis.
It was Canada that requested the formation of the group to address anticipated challenges to the supply of Technetium 99m (Tc-99m), a key medical isotope derived from Molybdenum-99 (Mo-99), produced at Chalk River.
Riatt says it's been no secret that the 52-year-old Chalk River NRU reactor has been nearing the end of its useful life and the government did try to prepare more than 10 years ago. In 1997, Canada began building two reactors dedicated to producing medical isotopes, the MAPLE project.
Those reactors were supposed to be running by 2000, but after 12 years of cost overruns, the reactors never worked well enough to be put into commercial production. AECL concluded last year that the project would have to be cancelled altogether.
Those alternatives include having patients use other forms of diagnostic imaging. Heart patients for example, are having tests using an older-technology isotope called thallium 202, which is more expensive than Tc-99m. Iodine 123 is being used to generate images of the thyroid. Like thallium, it's produced in a cyclotron, so is expensive and can be difficult for some hospitals to acquire.
