Medical Applications

Dr. Harold Johns of Saskatoon with his “Cobalt Bomb” in 1951
Dr. Harold Johns of Saskatoon with his “Cobalt Bomb” in 1951.

Nowhere is nuclear technology more widely accepted than in the medical field. Canada supplies a significant amount of the world’s medical isotopes for nuclear medicine, which are used every day in thousands of procedures here at home and around the world.

Nuclear medicine largely started in Canada in 1951, when the first two cancer treatment machines using cobalt-60 (radioisotopes) were built. One was built by Dr. Harold Johns of Saskatoon and one by Eldorado Mining and Refining Ltd., later to become part of Atomic Energy of Canada Limited (now Canadian Nuclear Laboratories) and then later again part of Nordion. Nordion provides innovative targeted cancer treatments for a variety of conditions including liver and brain cancer, and non-Hodgkins lymphoma. Many of these target cancer from within the body to deliver a higher concentration of treatment to the tumour.

cancer treatment machine
Cancer treatment machine.

Nordion is a global health science company that provides market-leading products used for the prevention, diagnosis and treatment of disease. We are a leading provider of medical isotopes, targeted therapies and sterilization technologies that benefit the lives of millions of people in more than 60 countries around the world. Although radiotherapy to treat cancer is the most commonly known use of nuclear technology in medicine, its application in diagnostics and research also makes up a significant portion of the use of radioisotopes in the medical field. Nordion is a global leader in supplying the world’s medical isotopes used to capture medical images. These images enable physicians to better diagnose and treat a multitude of diseases including cardiac and neurological conditions, in addition to several types of cancers.  Even today, nuclear medicine is one of the most powerful analytical tools available to physicians and patients because of its ability to provide dynamic views of organ structure and function.

Atomic Energy of Canada Limited’s NRU reactor produces 50% of the world’s medical isotopes
Canadian Nuclear Laboratories’ NRU reactor produces 50% of the world’s medical isotopes.

Canada’s nuclear infrastructure is essential to the global medical isotope supply. Nordion processes materials from Canadian Nuclear Laboratories (CNL) at the Chalk River Laboratories to produce a significant amount of the world’s medical isotopes. The need for radioisotopes and the vulnerability of their production was underscored when the NRU reactor at the Chalk River Laboratories was shut down on May 15, 2009 due to the discovery of a heavy water leak.  Repairs continued for over a year, until the NRU finally returned to service on August 17, 2010.

Thousands of daily diagnostic nuclear medicine procedures worldwide require molybdenum-99 that is produced by the NRU. This isotope is used in four out of five nuclear medicine procedures. Nordion is also the world’s leading supplier of the world’s cobalt-60 used to sterilize more than 40% of the world’s single-use medical supplies and devices, such as bandages, catheters and syringes. This technology is also used to sterilize a vast array of consumer products, including food, contact lens solution and cosmetics.

Research in health sciences and nuclear science has made nuclear technology one of the great tools of modern medicine.


Nordion Medical Isotopes,
Canadian Nuclear FAQ, Other Research and Development, Section 1.3: What is Canada’s role in nuclear medicine and isotope production?,
NRUCanada’s YouTube Channel,