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The unseen wonders of nuclear power

Millions of Ontarians benefit from electricity generated at Ontario Power Generation’s nuclear stations.

But did you know the company also brings benefits to people in many countries around the world as a supplier of isotopes such as heavy water, Cobalt-60 and tritium?

Discover how these stable and radioactive isotopes are key components in applications in medicine, sterilization, food preservation, luminescent lighting and fusion research.

The Climate Challengers

In 2020, we launched our Climate Change Plan and made a commitment to being a net-zero company by 2040, and create a net-zero economy by 2050. And while these goals are ambitious, they’re not enough on their own. That's where the Climate Challengers come in. Meet the people who have made it their mission to change the fate of our futures for the better.

For more info on OPG's energy podcast, visit or check out this episode 👉

EP07 - Nuclear medicine: Radiating health

EP07 - Nuclear medicine: Radiating health

Guests Jennifer Chapin & Dr. David Laidley discuss how Ontario’s nuclear reactors are becoming the backbone of the nuclear medicine industry.
See episode

How does Cobalt-60 benefit healthcare?

It's used to sterilize pharmaceutical products, surgical supplies and research equipment.

Breaking down isotopes

You may recall from your high school chemistry studies that every atom of every element is made up of protons, neutrons and electrons. Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons in their nuclei and, therefore, different atomic weights.

Isotopes can be naturally occurring or produced, stable or unstable. Deuterium, which bonds with oxygen to form heavy water, is a stable isotope. Heavy water is used to cool the fuel in CANDU and nuclear research reactors. Unstable isotopes such as Cobalt-60 and tritium undergo radioactive decay. During radioactive decay, energy is emitted and the element turns into a more stable form.

By harnessing the energy released by these isotopes, the medical and industrial worlds are able to provide essential services such as cancer treatment, sterilization and self-powered luminescent emergency lighting.

How does Cobalt-60 help keep hearts pumping?

Cobalt-60 is used to sterilize medical implants.

OPG solutions with Cobalt-60

About 40% of the world’s single-use medical devices, such as syringes, gloves, implants and surgical instruments, are irradiated and sterilized with Cobalt-60. The isotope emits gamma radiation, which makes it ideal to enhance the safety of medical products and perishable foods such as fruits, meats and spices.

Currently, Cobalt-60 is extracted from reactors at Pickering Nuclear and Bruce Power's Bruce B plant every 24 to 30 months. Plans are underway to expand Cobalt-60 production to Darlington Nuclear to ensure a steady supply as operations at Pickering wind down in 2024. Ontario’s CANDU reactors produce 50% of the world’s supply of the isotope.

How does Cobalt-60 help keep food safe?

Cobalt-60 is used to protect food products from harmful bacteria.

Nuclear next and new

OPG will soon expand the production of life-saving medical isotopes to its Darlington Nuclear station.

An innovative collaboration between OPG’s wholly-owned subsidiary, Laurentis Energy Partners, and BWX Technologies (BWXT) will see Molybdenum-99 harvested from reactors at Darlington.

Under this important supply agreement, the station will provide irradiation services to produce the isotope, which is used in over 30 million diagnostic and medical imaging treatments around the world each year, helping to detect illnesses like cancer and heart disease.

Darlington Nuclear will be the only source of Molybdenum-99 in North America, ensuring a stable domestic supply of this critical product.

Because of the unique design of Darlington’s CANDU reactors, medical isotopes can be removed while the reactor is still online, and without interrupting the station’s generation of clean energy. Once harvested, BWXT will utilize its newly designed, proprietary generators, called NeuCap1, to process the Molybdenum-99 into Technetium-99m, the final product that will be used in diagnostic imaging.