Isotopes and Medical Isotopes
Isotopes are atoms that have the same number of protons as each other, but different numbers of neutrons. There are both stable and non-stable isotopes, of which the unstable forms exhibit characteristic radioactive decay via electromagnetic (gamma) or particulate (alpha, beta, Auger, etc.) emission.
A “medical isotope” is simply a isotope that is used in the practice of medicine. Medical isotopes are the cornerstone of nuclear medicine, a branch of medical science that uses radioactive sources, atoms, and molecules to diagnose, characterize, and treat disease. Nuclear medicine encompasses the imaging techniques Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET), as well as the therapeutic interventions brachytherapy, radioembolic therapy, and Targeted Internal Radionuclide Therapy (TIRT). Some types of External Beam Radiation Therapy (EBRT) also use medical isotopes. Nuclear medicine physicians rely on access to more than a dozen different isotopes, which are matched to different applications depending on their chemical and radioactive decay properties.
Isotopes Production Chain
Isotopes are essential components of modern health care, natural resource development, and infrastructure management. Isotopes are used to characterize human disease, to detect contraband at international borders, to sterilize medical equipment, and to power batteries for space exploration. Isotopes also enable research in agriculture, astronomy, biology, chemistry, materials science, medicine, and nuclear safety. Canada has historically been a world leader in isotope production — a multi billion-dollar global industry — and has the physical and knowledge infrastructure necessary to make a major contribution to this important field on the international stage.
There is widespread awareness of the use of radiation and isotopes in medicine, particularly for diagnosis and therapy of various medical conditions. Medical isotopes are very important, particularly for diagnostic purposes in oncology; cardiology and neurology. Therapeutic applications, however, are quickly growing in use and will be a potential driver of market demand in the coming years. In therapeutics, by linking the correct medical isotope to a suitable tracer, the nuclear medicine specialist is able to deliver the medical isotopes to the correct site in the body. This significantly minimizes the damage to healthy cells while effectively killing the diseased cells.
QUICK FACTS ABOUT
Isotopes in Canada
Nuclear technology saves lives through use of isotopes for screening, diagnosis and therapy of a wide variety of medical conditions.
The Canadian Nuclear Safety Commission licenses the use and production of
over 250 isotopes in Canada.
In industrial radiography, nuclear substances are used for the non-destructive examination and testing of new materials. Radiation from the substances passes through the material and allows defects in welds or constituency to be recorded on film or a digital imager.
accounts for approximately 80% of nuclear medicine diagnostic procedures in Canada. According to the National Research Council of Canada, almost 5,500 diagnostic procedures are carried out every day with Tc-99m.
Canadian scientists were the pioneers in a number of nuclear applications.
In 1951, the world’s first cancer treatment with Co-60 took place in London, Ontario. This marked an important milestone for both the fight against cancer and Canada’s emergence as a leader in the field of nuclear power.
Irradiation technology is increasingly being used to preserve food
— spices, grains, fruit, vegetables and meat. It avoids the use of potentially harmful chemical fumigants and insecticides.
According to the Canadian Medical Imaging Inventory there were
diagnostic imaging procedures
in Canada in 2017.
Worldwide there are over
40 million nuclear medicine procedures
performed each year using isotopes, with approximately 36 million for diagnostic nuclear medicine and four million for therapy.
Currently, Lutetium-177 (Lu-177) accounts for 16% of the beta emitters in the Canadian therapeutic product market.
60% of the world’s market of Iodine-125 is produced at The McMaster Nuclear Reactor at McMaster University.
“Canada has been a pioneer in the development of radioisotopes, saving millions of lives in more than 80 countries for over six decades. We have demonstrated world-class nuclear expertise and achievements, leading to significant advancements in medical imaging, cancer therapy, sterilization, food and water safety, and disease prevention.”
John Gorman, President and CEO, Canadian Nuclear Association
How do we produce Isotopes in Canada
The production of medical isotopes is achieved using two overarching technologies: i) nuclear reactors, and ii) particle accelerators. Both reactor and accelerators/cyclotrons production methods rely on various chemical processes to separate, purify and prepare isotopes for medical use.
i. Nuclear reactors embody neutron-based production by using fission of a fuel material (typically uranium-235) to produce neutrons that are used to bombard target materials to form unstable products.
ii. Accelerators/cyclotrons utilize charged particles (proton, electron, neutron alpha, etc.) to accomplish the same.
Do accelerators and reactors produce the same isotopes?
Particle accelerators and nuclear reactors are complementary technologies. Radioisotopes generated in a particle accelerator are typically neutron-poor, meaning that they are unstable because they have too few neutrons. Radioisotopes generated in a nuclear reactor are typically neutron-rich – unstable because they have too many neutrons.