Medical Isotopes

Medical isotopes are used by medical professionals to diagnose and treat health conditions such as heart disease and cancer.

The production of medical isotopes is achieved by using two overarching technologies: nuclear reactors, and particle accelerators (linear accelerators, cyclotrons). Canada is home to one research reactor, three nuclear power stations (with reactors producing medical isotopes), twenty-five cyclotrons, and two linear accelerators.

Canada is a key player in the international supply chain of several medical isotopes, including:

• Cobalt-60, used in cancer radiation treatments, sterilizing medical devices and treatment of food and consumer products; and,
• Iodine-125 used for a number of medical uses including diagnostic procedures (nuclear medicine imaging, biological assays) and as brachytherapy in the treatment of some types of cancer.

Federally, Health Canada and the Canadian Nuclear Safety Commission (CNSC) play an important role in monitoring and regulating medical isotopes. Health Canada ensures that Canadians have access to safe and effective drugs and health products, including medical isotopes which are regulated and approved as medical devices or pharmaceuticals. The CNSC regulates the use of nuclear energy and materials, to protect the health, safety and security of Canadians and the environment.

Natural Resources Canada and Atomic Energy of Canada Limited once had a major role in the global and North American supply of Molybdenum-99 (Mo-99) and Iodine-131 (I-131), two of the most commonly used medical isotopes in Nuclear Medicine. Technetium-99m, which is derived from Mo-99, is used for about 82% of diagnostic imaging procedures^{Footnote 1} and I-131 is used for diagnosing and treating thyroid cancer and hyperthyroidism. With the closure of Canada’s National Research Universal Reactor in 2018, Canada now relies on foreign sources of these medical isotopes. Fluorine-18 (F-18) for diagnostic imaging using positron-emission tomography (PET) is produced using cyclotrons situated in most major medical centres across Canada.