PSEG’s Salem nuclear plant is preparing to produce cobalt-60, an isotope used to sterilize billions of medical devices and support cancer treatment.
TLDR:
1. PSEG, Westinghouse and Nordion plan to produce cobalt-60 at New Jersey’s Salem nuclear plant.
2. Cobalt-60 sterilizes more than 16 billion single-use medical devices annually in the United States, but the country currently depends entirely on foreign production.
3. The first cobalt targets could be installed in fall 2026, subject to federal approval; the first commercial harvest is expected around 2029.
New Jersey’s largest nuclear generating site is preparing to take on a second role beyond producing electricity: strengthening the nation’s medical supply chain.
PSEG Nuclear, Westinghouse Electric Company and medical isotope supplier Nordion plan to begin producing cobalt-60 at the Salem Nuclear Generating Station in Salem County. If successful, the project would establish the first commercial-scale cobalt-60 production platform in the United States and introduce the isotope to a type of reactor that accounts for most of the world’s commercial nuclear fleet.
The companies expect to install the first cobalt targets in Salem Units 1 and 2 later this fall, subject to federal regulatory approval and plant operating schedules. The first commercial supply of cobalt-60 is expected to be harvested around 2029, following several years inside the reactors.
The project could eventually supply at least half of U.S. demand for an isotope that is essential to modern health care but is not currently produced domestically.
What is cobalt-60?
Cobalt-60 is a radioactive isotope used primarily as a source of gamma radiation. Its largest application is sterilizing medical products that cannot withstand the heat, moisture or chemicals used in other sterilization methods.
Gamma irradiation can pass through sealed packaging and destroy bacteria, viruses and other microorganisms without leaving radioactive material behind in the treated product. The process is used on syringes, surgical gloves, catheters, implants, wound-care products and equipment used in pharmaceutical manufacturing.
Cobalt-60 is used to sterilize more than 16 billion single-use medical devices annually in the United States, according to the companies. It also supports certain cancer treatments, including stereotactic radiosurgery, and can be used to treat food, cosmetics, polymers and other commercial products.
The United States consumes approximately half of the world’s cobalt-60 supply because of its large medical-device manufacturing and health care sectors. However, it currently depends entirely on foreign reactors to produce the isotope.
Only about 20 reactors worldwide produce cobalt-60. Most of the supply comes from reactors in Canada, Argentina, China and India, while Russia also produces it. After the cobalt is removed from a reactor, it must be processed into sealed radiation sources by one of only a handful of specialized manufacturers.
How Salem would produce it
Cobalt-60 production begins with cobalt-59, the stable and naturally occurring form of the element. The cobalt-59 is placed inside a reactor, where it absorbs neutrons and gradually transforms into cobalt-60.
Westinghouse and Nordion began working together in 2019 to adapt that established process for use in pressurized water reactors. PSEG later joined the effort to prepare Salem Units 1 and 2 for the first commercial deployment.
Most cobalt-60 has traditionally been produced in Canadian-designed CANDU reactors or Russian RBMK reactors. Those facilities provide a different operating environment from Salem’s pressurized water reactors, which operate at higher temperatures and pressures.
At Salem, cobalt targets would be held at temperatures of about 608 degrees Fahrenheit and pressures of approximately 2,250 pounds per square inch. They could remain in the reactor for two or three 18-month operating cycles, resulting in a total irradiation period of three to five years.
To withstand those conditions, the companies developed a Cobalt Burnable Absorber, or COBA, insert. Each insert contains a series of rodlets holding capsules filled with cobalt-59. The insert is placed within a Westinghouse fuel assembly, but the cobalt remains separate from the nuclear fuel rods. The cobalt initially functions as a burnable absorber, a component used to help control reactivity inside a nuclear reactor. As it absorbs neutrons, it is converted into cobalt-60.
Once the material reaches the required activity level, it can be removed during a scheduled refueling outage and transported to Nordion for processing. The companies say the work can be performed without extending the outage or requiring permanent changes to the plant.
A second product from existing infrastructure
Salem Units 1 and 2 are pressurized water reactors; neighboring Hope Creek uses a different boiling water reactor design. Together, the Salem and Hope Creek plants produce more than 40 percent of the electricity generated in New Jersey and approximately 85 percent of the state’s carbon-free electricity.
The cobalt-60 project would allow Salem to produce a valuable medical material while continuing to generate electricity. It could also create a new recurring source of revenue from infrastructure already operating at the site.
The significance extends beyond New Jersey. Pressurized water reactors represent roughly 70 percent of the world’s more than 400 operating commercial nuclear reactors. Demonstrating that cobalt-60 can be produced safely and economically at Salem could provide a model for other U.S. plants.
PSEG submitted a license amendment request to the U.S. Nuclear Regulatory Commission in late 2025. The application includes both Salem-specific information and a broader technical component that could support future applications from other nuclear operators across the country.
Reducing dependence on foreign suppliers
Domestic production would not replace Canada and other existing suppliers immediately. Nordion, which has produced medical isotopes since 1946, would continue to operate within an international supply network.
However, adding U.S. reactors would diversify that network and reduce the consequences of an outage, transportation disruption or geopolitical conflict affecting one of the limited number of existing suppliers. The U.S. Department of Energy has identified cobalt-60 as a radioisotope for which domestic production capacity is critically needed. The Salem project could meet at least half of current U.S. demand, according to the companies. It would also create room to expand production if demand grows, particularly if the technology is adopted by other pressurized water reactors.
The timeline remains dependent on NRC authorization and the operating schedules of Salem’s two reactors. Even after the first targets are installed, the cobalt must remain inside the reactors for several years before the first commercial supply can be collected.
Sources:
American Nuclear Society. (2026, September 3). Westinghouse, Nordion, and PSEG team up to produce Co-60 in the United States. https://www.ans.org/news/2026-09-03/article-8326/westinghouse-nordion-and-pseg-team-up-to-produce-co60-in-the-united-states/
U.S. Nuclear Regulatory Commission. (2025, September 25). Salem Generating Station, Units 1 and 2: License amendment request to modify renewed facility operating licenses in support of cobalt-60 production. https://www.nrc.gov/docs/ML2526/ML25268A072.pdf
Westinghouse Electric Company. (2026, January 27). Westinghouse, Nordion and PSEG reach key milestones to launch first-ever production of cobalt-60 in U.S. pressurized water reactors. https://info.westinghousenuclear.com/news/westinghouse-nordion-and-pseg-reach-key-milestones-to-launch-first-ever-production-of-cobalt-60-in-u.s.-pressurized-water-reactors
