In addition to producing isotopes using nuclear reactors, there are also non-nuclear production alternatives. There is a technique to produce medical isotopes using so-called cyclotrons, or accelerators. Experimentation with this technique is ongoing. Cyclotrons can produce isotopes such as fluor-18 (widely used for PET scans), iodine-123 (for diagnosis of thyroid function), thalliuym-201 and rubidium-82 (with which doctors can detect heart disease). A number of medical isotopes can be produced on a large scale in a reactor, but not in an accelerator. This is the case for most of the therapeutic medical isotopes, and currently also for the well-known isotope molybdenum-99. Cyclotrons will never be able to replace reactors, but they can complement each other.
The ‘Lighthouse Initiative’ (Belgium) and Shine Medical Technologies LLC (‘SHINE’) (USA) hope to have the isotope molybdenum-99 available for diagnosis in the future. These projects are still in a development phase and the technology has yet to be proven.
For example, SHINE is investigating the possibilities of producing the molybdenum-99 (Mo-99) diagnostic isotope from low-enriched uranium (LEU) by using particle accelerator technology. With this technology, neutrons are shot via an accelerator at a liquid uranium mixture, which results in Mo-99. The advantage according to SHINE is that this new technology consumes less energy and the amount of radioactive waste relative to reactor-produced Mo-99 would also be smaller.
In addition to Mo-99, PALLAS also focuses on therapeutic isotopes. The market demand for therapeutic isotopes is expected to increase sharply worldwide. This only applies to a limited extent to diagnostic isotopes. The vast majority of therapeutic isotopes, including lutetium, can only be effectively produced in a reactor, and not in a accelerator. This also applies to SHINE technology. SHINE currently has a partnership with a research organization that is developing a purification process for irradiated lutetium, this process still needs to be scaled up. However, irradiation remains dependent on reactor capacity.
Different production techniques needed side by side
PALLAS embraces initiatives such as Lighthouse and Shine. After all, it is essential that there are enough medical isotopes available. The expectation is that the demand for medical isotopes will become so large in the future that we will need all different techniques for the production of isotopes alongside each other. In addition to SHINE and Lighthouse, PALLAS keeps a close eye on all alternative technologies and in its business case takes into account the success of one or more of them in the future.