Molybdenum-99 (99Mo): Past, Present, and Future

Mushtaq Ahmad, George Vandegrift, Pablo Cristini
2014 Science and Technology of Nuclear Installations  
Molybdenum-99 ( 99 Mo, half-life = 66 h) is a parent radionuclide of a diagnostic nuclear isotope. It decays in technetium-99 m ( 99m Tc, half-life = 6 h), which is used in over 30 million procedures per year around the world. To meet worldwide demand for 99m Tc-radiopharmaceuticals, fresh 99 Mo/ 99m Tc must be delivered regularly to nuclear medical centers, week after week. The risks of global 99 Mo supply disruptions increased significantly since 1995 and have been experienced for different
more » ... asons. Since the last quarter of 2007, global Mo-99 supplies have been severely disrupted by recurring operational problems at a handful of aging research reactor (NRU Canada, HFR Netherlands, SAFARI-1 South Africa, BR2 Belgium and OSIRIS France) and processing facilities (MDS Nordion in Canada, Mallinckrodt in the Netherlands, IRE in Belgium, and NTP in South Africa). These few facilities are meeting the bulk of the worldwide demand. With the aging of the 99 Mo supply network, it is necessary for world Mo-99 market to consider new reliable supply sources. The present and future shortage of 99m Tc or its parent is a worldwide issue. A research reactor is only one piece of the linear supply chain of 99 Mo/ 99m Tc that exists today. In April 2010, the United States and 46 other countries signed an agreement to phase out HEU for civilian uses to reduce proliferation concerns. Now scientists and engineers involved in 99 Mo production are working to determine how to continue to make 99 Mo with (1) low-enriched uranium (LEU, <20% 235 U) or (2) other alternatives that do not require fissioning of 235 U. To overcome the shortage of various routes of its production by accelerators and reactors generating high and low specific activity 99 Mo or 99m Tc directly is being researched. Investigators were invited to contribute original research articles as well as review articles to stimulate the continuing efforts to understand the issues related to production of 99 Mo that is acceptable to end users and environmentalists. The article selected for this special issue represent the rich and many-faceted technical know-how that we have the pleasure of sharing with our readers. We would like to thank the authors for their excellent contributions and patience in assisting us. Finally, the fundamental work of all reviewers on these papers is also highly appreciated. This special issue contains nine papers, where four papers deal with the production of 99 Mo using LEU targets in a reactor. Two papers are on 99m Tc generators development and its utilization. One paper deals with the production of 99 Mo and 99m Tc using a cyclotron. An article on immobilization of higher activity wastes from reactor production of 99 Mo is also included in this issue. One paper deals with research and development of chemical process, hot-cell infrastructure, and commercial production of 99 Mo. In the paper entitled " 99 Generator Development: Up-to-date 99 recovery technologies for increasing the effectiveness of 99 Mo utilization" by V. S. Le (Australia) presents a review on the 99 Mo sources available today and on the 99m Tc generators developed up to now for increasing the effectiveness of 99 Mo utilization. The latest results of the endeavors in this field are also surveyed in regard to the technical solution for overcoming the shortage of 99 Mo
doi:10.1155/2014/839369 fatcat:37ukiprt7zd5lhlqnku47sisra