Medical Isotope Production Without Highly Enriched Uranium (2009)

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Summary T his report is the product of a congressionally mandated study to examine the feasibility of eliminating the use of highly enriched uranium (HEU) in reactor fuel, reactor targets, and medical isotope production facilities. The report focuses primarily on the use of HEU for the production of the medical isotope molybdenum-99 (Mo-99), whose decay product, technetium-99m (Tc-99m), is used in the majority of medical diagnostic imaging procedures in the United States, and secondarily on the use of HEU for research and test reactor fuel. This summary is organized around the four study charges provided by Congress and a fifth study charge negotiated between the National Academies and the study spon- sor, the Department of Energy’s National Nuclear Security Administration (DOE-NNSA). The fifth charge was formally approved by the sponsor and the National Academies prior to the start of the study. The complete study charge is given in Sidebar 1.2.   The study was mandated by Section 630 of the Energy Policy Act of 2005 (Public Law 109-58). See Appendix A.   HEU is uranium enriched in uranium-235 (U-235) to concentrations greater than or equal to 20 weight percent. Uranium enriched in U-235 to concentrations less than 20 weight percent is low enriched uranium (LEU); see Sidebar 1.1.   The “m” denotes that this radionuclide is metastable.  

 MEDICAL ISOTOPE PRODUCTION WITHOUT HIGHLY ENRICHED URANIUM CHARGE 1: FEASIBILITY OF PROCURING SUPPLIES OF MEDICAL ISOTOPES FROM COMMERCIAL SOURCES THAT DO NOT USE HEU The authoring committee for this report (Appendix B) provides a detailed examination of feasibility in Chapter 10. This examination is supported by information and analyses in Chapters 2, 7, 8, and 9. The committee finds that: • Low enriched uranium (LEU) targets that could be used for large- scale production of Mo-99 have been developed and demonstrated. • These targets could be used in reactors and processing facilities that produce large-scale quantities of medical isotopes for the U.S. market. However, existing producers might have to make modifications to their process equipment and to their chemical separations processes to use these LEU targets. The targets would also have to be compatible with existing or planned reactors. Conversions could require significant expense (tens of millions of dollars) and time (ranging from a few months to about 13 years) depending on whether it was carried out in existing or new facilities. • At the present time there are not sufficient quantities of medical isotopes available from LEU targets to meet U.S. domestic needs. However, the committee sees no technical reasons that adequate quantities cannot be produced from LEU targets in the future. CHARGE 2: CURRENT AND PROJECTED DEMAND AND AVAILABILITY OF MEDICAL ISOTOPES IN REGULAR CURRENT DOMESTIC USE The committee examined the availability and demand for Mo-99 for domestic use in Chapters 3, 4, and 5. The committee finds that: • Current (2006) demand for Mo-99 in the United States is between 5000 and 7000 6-day curies per week. U.S. supply/demand probably has not changed appreciably since 2006. • Demand growth for Mo-99/Tc-99m in the United States over the next 5 years could range from 0 to 5 percent per year with the most likely growth rate in the range of 3 to 5 percent per year. • Demand growth for diagnostic imaging will likely continue over the long term as the U.S. population ages. The extent to which this will be   That is, production of greater than 1000 6-day curies of Mo-99 per week. See Sidebar 3.1.   Most producers calibrate the sale price to the number of curies present in a shipment of Mo-99 6 days after it leaves the producer’s facilities. This quantity is referred to as 6-day curies. See Sidebar 3.1. 

SUMMARY  reflected in the demand for Mo-99/Tc-99m will depend strongly on whether other diagnostic imaging modalities find widespread use in the United States, which is unlikely to happen in the foreseeable future. • Reliability of supply is impacting the availability of Mo-99 for medical use and the continuity of patient care in the United States and elsewhere. Reliability of Mo-99 supply is likely to continue to be a serious problem for the United States in the early part of the next decade without new supply sources. • Conversion from HEU to LEU targets would remove policy uncer- tainties associated with the continued availability of HEU for use in Mo-99 production. However, conversion would not address any of the other ­supply reliability concerns associated with current HEU-based production. • Although there are other potential foreign and domestic sources of Mo-99 supply, it will take several years for substantial supplies from these producers to become available. • Because current supplies of Mo-99 are produced in reactors built largely at government expense, private companies that can provide new domestic supplies of Mo-99 to the market might not choose to compete without government assistance. A possible exception is Babcock & Wilcox, which has indicated that it is interested in producing Mo-99 but has not announced firm plans to build a production facility. CHARGE 3: PROGRESS BEING MADE BY THE DEPARTMENT OF ENERGY AND OTHERS TO ELIMINATE ALL USE OF HEU IN REACTOR FUEL, REACTOR TARGETS, AND MEDICAL ISOTOPE PRODUCTION FACILITIES An examination of the progress that is being made in eliminating HEU use is provided in Chapter 11. The committee finds that: • DOE-NNSA, in collaboration with several other organizations, has made substantial progress in converting reactor fuels and targets to LEU through the Global Threat Reduction Initiative (GTRI). The committee recommends that the GTRI program be continued until research and test reactors worldwide have converted their fuel and targets to LEU or have been permanently shut down and their HEU fuel has been returned to the country from which it originated. • Despite this progress, the GTRI program faces several challenges. There are 78 HEU-fueled research and test reactors operating through- out the world that are out of the scope of GTRI. From a purely techni- cal perspective, it appears that most of these reactors can be converted to LEU even if they have a unique fuel design or a defense mission. The 

 MEDICAL ISOTOPE PRODUCTION WITHOUT HIGHLY ENRICHED URANIUM committee recommends that DOE-NNSA, in cooperation with the Inter- national Atomic Energy Agency (IAEA), make an effort to maintain an up-to-date and comprehensive database of the research and test reactors of the world, including large pulse reactors, critical facilities, and reactors with a defense-orientated mission. The committee also recommends that these reactors be investigated to determine if it is feasible to convert them to LEU; if so, they should become in-scope for the program. • Converting Mo-99 production worldwide to LEU will continue to be a major challenge for GTRI and its Reduced Enrichment for Research and Test Reactors (RERTR) Program. Recommendations on additional steps that can be taken to encourage conversion are provided in response to the fifth study charge. The committee recommends that the RERTR Program increase its focus on eliminating HEU wastes that result from Mo-99 production facilities using U.S.-origin HEU by examining options to downblend this waste or encouraging its return to the United States. CHARGE 4: POTENTIAL COST DIFFERENTIAL IN MEDICAL ISOTOPE PRODUCTION IN THE REACTORS AND TARGET PROCESSING FACILITIES IF THE PRODUCTS WERE DERIVED FROM PRODUCTION SYSTEMS THAT DO NOT INVOLVE FUELS AND TARGETS WITH HEU The committee focused on costs of producing Mo-99 because it is the precursor of Tc-99m, which is by far the major medical isotope used ­today. The committee provides a detailed examination of Mo-99 production costs in Chapters 6 and 10. The committee estimated average costs at three points in the Mo-99/Tc-99m supply chain, Mo-99 production, technetium generators, and Tc-99m doses: • Costs of Mo-99 production in 2008: about $225 per 6-day curie with a cost variation of about ± 40 percent. • Average prices for technetium generators sold in the United States in 2005: about $1900 for a generator with 10 curies with a variation of about ± 25 percent. • Average prices for Tc-99m sold in the United States in 2005: about $11.00 per 30 mCi dose of Tc-99m sodium pertechnetate, with a variation greater than ± 20 percent.   These reactors do not include HEU-fueled naval propulsion reactors or related test beds and training reactors.   The quantity of Mo-99 in a technetium generator is typically calibrated to be the quantity present on the day or day after it is delivered to a customer. This quantity is different from the 6-day curie quantities sold by Mo-99 producers. 

SUMMARY  The committee finds that: • The anticipated average cost increase to convert to the produc- tion of medical isotopes without the use of HEU would likely be less than 10 percent for at least three of the four current large-scale producers (MDS Nordion, Mallinckrodt, and Institut National des Radioéléments). This is true for costs and/or prices at all three points in the Mo-99/Tc-99m ­supply chain that were examined by the committee. In fact, a 10 percent cost i ­ncrease for Mo-99 would provide very substantial resources for conver- sion and would have a negligible impact on the cost of common diagnostic imaging procedures. The committee has insufficient information regard- ing ­ potential conversion costs for the South African producer Nuclear T ­ echnology Products Radioisotopes. This result is based on assumed future facility operations of 30–50 years. For the High Flux Reactor (HFR) at Petten, it is assumed that development of LEU targets and processes would carry over to the to-be-built Pallas ­reactor, so that a long amortization period is justified. The committee is unable to as- sess whether the use of a 30-year operating period is consistent with Atomic Energy of Canada Limited’s (AECL) long-term plans for Mo-99 production. AECL has not indicated what plans it has for producing Mo-99 beyond 2016 and was not willing to discuss with the committee what refurbishment is needed to keep National Research Universal (NRU) running until 2016. If AECL decides to get out of the business of producing Mo-99, then obvi- ously a shorter amortization period would need to be used. CHARGE 5: IDENTIFY ADDITIONAL STEPS THAT COULD BE TAKEN BY DOE AND MEDICAL ISOTOPE PRODUCERS TO IMPROVE THE FEASIBILITY OF SUCH CONVERSIONS The committee recommends that Mo-99 producers and the U.S. gov- ernment consider several steps to improve the feasibility of conversion; additional details are provided in Chapter 10: • Mo-99 producers: Commit to conversion, announce a best-effort schedule for selecting and implementing an LEU-based Mo-99 produc- tion process, and identify additional needs for technical assistance. Work with industry organizations and scientific and medical societies concerned with Mo-99 production for marshalling, coordinating, and supporting an i ­ndustry-wide conversion strategy. • DOE: Make the considerable technical expertise of the DOE n ­ ational laboratory system available to assist existing producers with conversion-related research and development (R&D) and examine options 

 MEDICAL ISOTOPE PRODUCTION WITHOUT HIGHLY ENRICHED URANIUM to share R&D costs with existing and potential new producers that could supply the U.S. market as a means to incentivize the conversion process and encourage new domestic production. Remove disincentives to conversion by maintaining the cost of LEU so that it is no more expensive than HEU on a common U-235 mass basis. • Department of State: Intensify the diplomatic pressure on countries that still use HEU (fuel or targets) to induce them to convert. In particular, those countries that are partners in GTRI and have made a commitment to the “minimization of HEU” should be encouraged to live up to their com- mitments; this includes Canada, the Netherlands, Belgium, and France. • Food and Drug Administration (FDA): Work with industry and DOE’s technical experts to ensure that there is a common understanding of LEU-based production of Mo-99 from a regulatory perspective, and also that there is a good understanding of likely FDA requirements for obtaining regulatory approvals for the use of this isotope in radiopharmaceuticals. • U.S. Congress: Provide clear and consistent policy signals con- cerning conversion to LEU-based Mo-99 production. Consider additional controls on the use of U.S.-origin HEU for medical isotope production and incentives to motivate conversion and the development of domestic sources of Mo-99. Some possible incentives are described in Chapter 10.