Sealed radioactive sources are used every day in equipment to treat cancer, sterilise blood and make food safe to eat. But with circular economy and sustainability in mind, manufacturers and users are looking for ways to reuse and recycle the sources and radioactive devices, and so reduce waste too.
The IAEA has brought together decision makers, users, regulators, manufacturers, suppliers and waste management specialists to share their strategies and experiences. The initiative will lead to the publication of a technical document on the reuse and recycling of disused sealed radioactive sources (DSRS).
“Nowadays, reuse and recycling have become essential steps in the management of DSRS,” said Tamara Djurovic of Montenegro’s nuclear regulatory authority during an IAEA Technical Meeting last month. “But many countries still do not think of DSRS as an in-country resource that can be reused and save funds.”
The sources are robust stainless steel capsules about the size of a small coin or a needle which contain radioactive material – typically Cobalt-60, Caesium-137, Americium-241 or Radium-226. Each capsule is designed to have a recommended working life of 10 to 15 years and is licensed to a specific owner for a specific use. Sources become disused when the owners do not need them anymore or when they have reached their service life for a given purpose.
In many cases, the capsules could be relicensed and reused in the same or similar applications. At the Technical Meeting, several participants reported that such a transfer between companies was a frequent way to reuse a source – for example, the transfer of soil moisture gauges was very common. Sometimes they could be sent to manufacturers to be reconditioned for a different type of applications.
Reuse and recycling of sources is a more sustainable use of resources, and it is cost efficient too. “For example, Cobalt-60 manufacturers are recycling as much Cobalt as they can find because demand is so high. They wouldn’t do that if it didn’t make economic sense,” said John Zarling, an IAEA engineer specialised in DSRS.
With information and practical strategies to deal with disused capsules much in demand, the Technical Meeting – held virtually and in person in Vienna – attracted 108 participants from 59 countries. “It is really encouraging that we already have so many examples of good practice,” said Maura Ioana Petcu of the Romanian National Commission for Nuclear Activities Control. “The reuse or recycling of DSRS could really be a viable option for sustainable management of DSRS.”
Significant challenges remain, however. In particular, transport costs for sending a disused source from one country for recycling in another country can be prohibitively high. To overcome this, several countries including India and the Philippines are venturing into R&D to reuse and recycle the disused sources themselves, so that they no longer need to return them to the supplier.
“It’s our aim that countries will use the information disseminated during the meeting and the Technical Report, once published, as a practical guide for reusing and recycling DSRS,” said Juan Carlos Benitez-Navarro, an IAEA DSRS specialist.
