18 Dec (NucNet): The production of the most widely used medical radioisotope, molybdenum-99 (Mo-99), depends largely on a small number of reactors that are ageing and facing unplanned outages, refurbishment outages or permanent shutdowns, increasing the risk of disruption to the supply chain, a joint declaration signed by 11 countries says.
The declaration, presented yesterday to the Organisation for Economic Cooperation and Development’s (OECD) Council, says new infrastructure needs to be developed to replace these facilities before they shut down.
It also says “an unsustainable economic structure” is threatening the reliability of the Mo-99 supply chain and that global action to move to “full-cost recovery” is necessary to ensure economic sustainability and long-term secure supply. Full-cost recovery would ensure that for-profit companies involved in the supply chain recover the full cost of their operations including the relevant proportion of overheads.
The OECD’s Nuclear Energy Agency (NEA) said the declaration sends a clear signal to those in the supply chain that governments have “the resolute intention” to take coordinated action to ensure the long-term security of supply of Mo-99.
The governments of Australia, Canada, Germany, Japan, the Netherlands, Poland, South Korea, Russia, Spain, the UK and the US have formally adhered to the declaration.
The declaration promotes full cost recovery of isotope production and the availability of reserve capacity. It also provides a platform for discussions among participating countries on their involvement in the supply chain for Mo-99.
It says governments that have adhered to the declaration intend to ensure that producers of Mo-99 and its decay product technetium-99m (Tc-99) implement “a verifiable process” for introducing full-cost recovery at all facilities that are part of the supply chain.
Mo-99 is the most widely used medical isotope, used approximately 40 million times worldwide every year in advanced medical diagnoses. It is produced through irradiation of uranium targets in various research reactor facilities around the world.
Mo-99, which has a 66-hour half-life, decays to Tc-99 as it is packaged and shipped for use by physicians. It is the Tc-99 which is injected into patients to enable sophisticated imaging techniques needed to diagnose cancer, heart disease and other ailments. Tc-99 has a very short half-life – only six hours – and it decays to nonradioactive materials and thus limits patient exposure.
Because Mo-99 and Tc-99 have such short half-lives, they must be produced continuously. Disruptions in the supply chain can lead to cancellations or delays in important medical testing services.
The NEA said: “Unfortunately, supply reliability has declined over the past decade due to unexpected or extended shutdowns at a few of the ageing, Mo-99-producing research reactors and processing facilities. These shutdowns have created conditions for global supply shortages.”
At the request of its member countries, the NEA became involved in efforts to ensure a secure supply of Mo-99. Since June 2009, the NEA and its High Level Group on the Security of Supply of Medical Radioisotopes have examined the causes of supply shortages.
Governments are involved in the supply chain primarily at each end, at the reactor and end-use levels. Most Mo-99 producers represented in between are commercial, for-profit entities. Although governments have been reducing their support for Mo-99 irradiations at reactors, much remains to be done to achieve universal implementation of full-cost recovery, the NEA said.
Some governments continue to subsidise Mo-99 production, thus supporting healthcare systems both nationally and in other countries. While it is their prerogative to fund basic research at reactors, any commercial Mo-99 production as part of the global supply chain should comply with the principle of full-cost recovery to avoid distorting the market, the NEA said.
Five reactors produce the bulk of global Mo-99 supply. They are the High-Flux Reactor (HFR) at Petten in the Netherlands, BR2 in Belgium, Osiris in France, Safari in South Africa and the National Research Universal (NRU) reactor in Canada.
The joint declaration is online: http://www.oecd-nea.org/med-radio/jointdeclaration.html
