How are radioactive isotopes used to sterilize medical instruments?

Radioactive isotopes, most notably cobalt-60, are used to sterilize medical instruments through a process known as radiation processing. This method utilizes the gamma radiation emitted by the isotope to effectively eliminate pathogens on disposable medical supplies, such as syringes, hospital gowns, and blood transfusion kits.1

The sterilization process works because ionizing radiation possesses enough energy to disrupt the molecular structure of biological organisms, often by causing breaks in the DNA molecules within cells, which prevents them from replicating and leads to their destruction.2

To ensure safety, the radioactive source is encapsulated in a double layer of stainless steel to prevent environmental contamination. Importantly, exposure to these gamma rays does not induce radioactivity in the medical instruments themselves, making the technique a safe and efficient alternative to conventional sterilization methods.1