Medical isotopes

It is technically and financially feasible to use low-enriched uranium to produce medical isotopes on a commercial scale. That is the conclusion of a National Research Council (NRC) report released in January.

Congress commissioned the report to explore the conflicting goals of restricting exports of highly enriched uranium (HEU) for medical isotope production, per the Energy Policy Act of 1992, and ensuring a reliable supply of isotopes, to which end a later law lifted the export restrictions (see Physics Today, May 2008, page 22 ). “The question we pursued was the feasibility of achieving both,” the chair and vice chair of the study write in the report.

The most common radioisotope used in medicine is technetium-99m, a decay product of molybdenum-99, which is obtained from uranium fission. The NRC report finds that facilities can convert from HEU, which poses a proliferation risk, to LEU to produce ⁹⁹ Mo with a cost increase of less than 10%, and that the cost increase is “much less important than is reliability of supply.” Moreover, the increased cost to patients for radioisotope pharmaceuticals would be less than 1%.

“I think Congress is likely to adopt the report’s two main recommendations—restoring restrictions on HEU exports and enacting incentives for production and/or purchase of medical isotopes produced with LEU,” says Alan Kuperman, director of the nuclear proliferation prevention program at the University of Texas at Austin. “The days—or at least the years—of HEU-based isotope production are numbered.”