The U.S. Department of Energy is studying whether to sign off on an extension of the legal deadline to end exports of weapon-grade uranium for foreign production of the medical isotope molybdenum-99 (Mo-99).
The agency’s semiautonomous National Nuclear Security Administration (NNSA) is accepting comments from the public through Dec. 27 ahead of the secretarial certification of supply of the isotope produced without use of highly enriched uranium.
Molybdenum-99 decays into the isotope technetium-99m, which the NNSA said in a Nov. 27 Federal Register notice is employed in 40,000 medical diagnostic and therapeutic procedures each day in the United States, including for heart-disease diagnosis and cancer treatments. Prior to last year, the United States for decades had depended entirely on foreign sources of Mo-99. A number of U.S. companies aim to rebuild the domestic capacity – NorthStar Medical Radioisotopes, of Beloit, Wis., has been supplying the isotope for a year as of November, but the nationwide effort remains in its early stages.
The American Medical Isotopes Act of 2012 set a seven-year deadline after which the U.S. Nuclear Regulatory Commission could no longer issue licenses for export of highly enriched uranium for production of the targets that are then used in manufacturing Mo-99. The material itself is supplied by the NNSA, the Energy Department’s civilian steward for the U.S. nuclear arsenal, through the Y-12 National Security Complex in Tennessee.
The intent of the law is to eliminate the potential proliferation danger posed by sending HEU to civilian isotope production plants in other nations. Foreign suppliers have been converting to use of low-enriched uranium (LEU) or other means for isotope manufacturing. Three of the four major providers to the U.S. — from Australia, South Africa, and the Netherlands — have always used LEU or have converted to the proliferation-resistant material. The fourth, Belgium’s Institute for Radioelements (IRE), is in the process of converting, NNSA spokesman Dov Schwartz said by email Friday.
The export prohibition is dependent on a joint certification by the energy and health and human services secretaries that the United States has an adequate supply of Mo-99 produced without highly enriched uranium to meet patient needs, and thus that export of domestic material is no longer necessary. Failing that finding, the export prohibition can be pushed back by as much as six years.
“DOE/NNSA is working closely with the Department of Health and Human Services to analyze all available information to determine the sufficiency of the Mo-99 supply produced to meet the needs of patients in the United States,” Schwartz wrote.
Between 2014 and 2018, the Nuclear Regulatory Commission approved 20 of 21 license applications for export of highly enriched uranium. Ten of the approved licenses were for material to be used in production of medical isotopes, encompassing 54.2 kilograms of weapon-usable plutonium.
The NRC is currently considering an NNSA license application for export of nearly 4.8 kilograms of uranium enriched up to 93.35% for isotope production by the Institute for Radioelements. Isotope production rivals and nonproliferation advocates are objecting to the potential license.
The NNSA is seeking comments on six specific questions, including: Does the United States have a sufficient supply of Mo-99 for patient requirements; do existing supplies of Mo-99 produced without HEU satisfy domestic demand; what has led to supply shortages in the U.S.; and how would the export prohibition affect the nation’s Mo-99 supply.
Comments can be submitted by mail to Joan Dix, deputy director of the NNSA’s Office of Conversion, at 1000 Independence Ave. SW, Washington, DC 20585, or by email to [email protected].