May 12, 2021
Julia Phillips, Miles A. Pomper, William Tobey
The following was originally published at the Bulletin of the Atomic Scientists.
Neutrons are keys that unlock atomic explosions and the controlled generation of electricity in nuclear power reactors, and they advance a wide variety of human purposes. Among other uses, they help to: test and qualify new power reactor designs and fuels; manufacture medical isotopes to treat and diagnose deadly diseases such as cancer and cardiovascular ailments; and advance basic research in chemistry, physics, and the life sciences.
A wide variety of institutions own and operate the research reactors that produce neutrons to meet these needs, including governments, universities, private companies, and national laboratories. Perhaps because of this diverse ownership base, there is no central mechanism within the United States or globally that assesses neutron needs for medical, scientific, and industrial purposes and how to meet them. Yet, such reactors are not cheap. Jordan’s Research and Training Reactor, which first went critical in 2016, reportedly cost $161 million. Moreover, because of long construction lead times, extensive and lengthy regulatory reviews, and the finite operational lifetimes of existing reactors, accurate planning is essential. Gaps in neutron production could cost lives; excessive redundancy would be very expensive.
For these reasons, a 2016 National Academies of Sciences, Engineering, and Medicine study committee (chaired by Phillips and including Tobey) recommended that the United States develop a 50-year strategy “that enumerates and evaluates the importance of anticipated US civilian needs for neutrons and provides a roadmap for how these can best be provided by reactors and other sources that do not use highly enriched uranium.”
That recommendation, however, didn’t go far enough. After all, the market for neutrons and their products and benefits is global. Fifty-three countries operate some 224 research reactors, with nine new plants under construction. Ten such facilities supply more than 95 percent of one of the world’s leading medical isotopes, and many of those, including all of the high-performance reactors in the United States, have operated for nearly half a century, if not more. Thus, international planning and coordination of neutron needs and how to supply them are vital.
The issue is complicated by today’s use of highly enriched uranium in the production of some medical isotopes, either as research reactor fuel or in the targets that are transformed into the beneficial isotopes. Using highly enriched uranium incurs risk that the material will be diverted or stolen for use in nuclear weapons. To prevent this, more than 100 research reactors fueled by highly enriched uranium have been converted to use low enriched uranium or been shut down. More work, however, remains to be done, as some 72 highly enriched uranium-fueled research reactors powered continue to operate.
Continue reading at the Bulletin of the Atomic Scientists.
