(This is the first in a series of two HillNotes on The International Security of Medical Isotope Supply. Part two provides an assessment of potential technologies.)
The global supply of medical isotopes remains uncertain, despite increased efforts at home and abroad to secure production sources. The isotope technetium-99m (99mTc) is of particular concern, given its role in enabling early, accurate and non-invasive diagnosis of diseases such as heart conditions and cancer.
Supplies of 99mTc, and its parent isotope molybdenum-99 (99Mo), have been a pressing issue since the 2009–2010 shortage triggered by unplanned nuclear reactor shutdowns in Canada and the Netherlands. Over the past decade, some of the world’s most important 99Mo-producing reactors have been approaching the end of their operational lives, which has undermined the security of the international 99Mo/99mTc supply chain.
In Canada, the federal government announced last February that it would discontinue its routine 99Mo-production from the country’s leading isotope-producing facility, the National Research Universal (NRU) reactor, by 2018. The government has been investing in non-reactor-based technologies to supply the domestic market.
Medical isotope security, an international issue
The security of the 99Mo/99mTc supply chain is an international issue because, currently, only a handful of government-owned nuclear reactors supply over 90% of the world’s 99Mo demand. 99Mo is the predominant source of 99mTc, the isotope used for roughly 80% of the world’s nuclear medicine procedures (about 30–40 million examinations every year).
The “niche” 99Mo/99mTc market, according to the Canadian Nuclear Safety Commission, has been distorted by direct or indirect government subsidies, causing the cost of medical isotopes to remain artificially low, and undermining competition from private developers. Now that the primary 99Mo-producing reactors are becoming less reliable, it is widely recognized that new or replacement technologies are needed under a more sustainable economic structure.
In its most recent forecast of future 99Mo/99mTc supply, the OECD Nuclear Energy Agency (NEA) predicts that the current global irradiation and processing capacity will likely be insufficient over the 2015–2020 period. The Agency stresses the need to establish an economically sustainable supply chain, as quickly as possible, to avoid further disruptions of important medical diagnostic tests.
International progress “slower-than-desired”
An international policy approach was set forth by the High-level Group on the Security of Supply of Medical Radioisotopes (HLG-MR) and endorsed, in a joint declaration, by the ministers and representatives of 13 countries, including Canada. The HLG-MR approach urges governments and industry to work towards:
- implementing full-cost recovery for all new and replacement technologies;
- establishing a reserve capacity that is sourced and paid for by the supply chain;
- fostering market-driven investment through a business and regulatory environment that promotes safe and efficient market operation;
- promoting nuclear non-proliferation by favouring low-enriched uranium (LEU) technologies; and
- international collaboration towards a globally consistent approach to secure 99Mo/99mTc supplies.
Based on the most recent self-assessment of individual countries, the NEA concluded that progress towards implementing the HLG-MR principles has been “slower-than-desired.” According to the Agency, commercial considerations continue to threaten the long-term sustainability of 99Mo production, thereby perpetuating an environment of unhealthy competition and inefficient market outcomes.
The NEA is of the view that a secure global supply of 99Mo will likely be based on a network of research reactors in the foreseeable future, especially given the reliance of the current supply chain on reactor-driven production.
Canada pursues alternative technologies
In Canada, the federal government is discontinuing its routine 99Mo-production, while investing in alternative, accelerator-based technologies to supply the domestic market.
The government will decommission the NRU reactor in Chalk River, Ontario, after March 2018 (17 months later than originally planned), effectively ending Canada’s contribution to the global 99mTc supply chain. The ageing NRU is one of the largest and most versatile research reactors in the world. While capable of producing almost half of the global 99Mo demand in a normal week, it currently supplies about 33% of the international market.
Meanwhile, the government has invested $60 million in the research, development and demonstration of cyclotrons and linear accelerators, through the Non-reactor-based Isotope Supply Contribution Program and the Isotope Technology Acceleration Program. The anticipated technologies are expected to supply the domestic market only. Cyclotrons, which produce 99mTc directly, must be located close to end-use facilities, given the isotope’s short half-life of only six hours, while the linear accelerator option will likely be used to supply remote locations.
Canada’s accelerator-based production is expected to operate on a full cost-recovery basis after 2016.
Uncertainty moving forward
For the time being, the future security of 99mTc supply remains largely a work in progress. Recent announcements by TRIUMF, the Canadian Light Source centre and the Sherbrooke Molecular Imaging Centre indicate possible headway in advancing the commercial viability of accelerator-based technologies in Canada.
Internationally, there is hope that the anticipated commissioning of new capacity may counterbalance the planned exit of some reactors before 2020, especially now that the decommissioning of the NRU has been extended to 2018.
- Health Canada. Medical Isotopes – Frequently Asked Questions.
- OECD Nuclear Energy Agency. Supply of Medical Radioisotopes series.
- Zakzouk, Mohamed. The 2009–2010 Medical Isotope Shortage: Cause, Effects and Future Considerations. Publication no 2009-04E. Parliamentary Information and Research Service, Library of Parliament, Ottawa, 17 November 2010 (archived).
For more information on potential technology options, please see part two of this HillNote series: Assessment of Potential Technologies
Author: Mohamed Zakzouk, Library of Parliament