A coordinated international response to the global shortage of radioactive isotopes used to diagnose and treat cancer patients is urgent, says the IAEA. The global shortage of molybdenum-99, caused by the shutdown of nuclear reactors in Canada in the fall of 2007 and in the Netherlands in recent months has led to a decrease in the delivery of critical nuclear medicine diagnostic services worldwide.
"It is very important to guarantee the uninterrupted supply of molybdenum-99 to serve the needs of the nearly 100,000 patients who undertake daily medical procedures with radiopharmaceuticals containing technetium-99m radio isotope," said Werner Burkart, the International Atomic Energy Agency's Deputy Director General for Nuclear Sciences and Applications.
The isotope technetium-99m, derived from molybdenum-99 (a related radioactive substance), is injected into patients undergoing cardiac stress tests or body scans for cancer, heart disease and bone or kidney illnesses. The procedure is used in about 25 million medical diagnoses annually.
"Hospitals and doctors are having to prioritize diagnostic procedures for really critical care," said Ralph Butler, Director of the Missouri university research reactor (MURR), as quoted by the Associated Press.
A month long shutdown of a government-owned reactor in Canada last year created a critical shortage, with doctors forced to delay necessary tests. The Canadian reactor supplies half the world's supply of the medical isotopes. The world's second leading supplier of the radioactive isotope, a reactor in the Netherlands, shut down in August and is not scheduled to reopen until mid February 2009 at the earliest. The other major facilities producing for the international market are in Belgium and South Africa.
Fueling the need for more production of what experts call "moly-99" is the surge in nuclear medicine technology, said Natesan Ramamoorthy, Director of the International Atomic Energy Agency's physical and chemical sciences division. "Use has been expanding. Simultaneously, production facilities are getting older and older. So we need more players," he said.
In addition, the growing international consensus to eliminate the civilian use of Highly Enriched Uranium is leading to pressure on the commercial manufacturers of molybdenum-99 to convert to the use of low-enriched uranium targets for the production of Mo-99 to reduce nuclear proliferation and security risks. The IAEA is helping to promote the adoption of LEU-based Mo-99 production technology under a Coordinated Research Project (CRP).
"There is broad technical agreement that (low-enriched uranium) is viable" for medical isotopes," said Ira Goldman, a project manager with the International Atomic Energy Agency."Anybody that would a start new facility now would use LEU," he said. "The more you are able to produce these isotopes closer to where they are being used, the greater the advantage in both cost and security," said Goldman.
In response to the shortage, scientists participating in the CRP and observers from 18 countries, including Argentina, Chile, India and Poland, met at the University of Missouri Research Reactor in October to coordinate research and spur commercial development of the substance.
An Argentinean reactor that sells molybdenum-99 to nine countries (as technetium-99m generators) already manufactures this isotope with low-enriched uranium. In its turn, the U.S. Department of Energy has been working since 1978 to make it possible for research reactors and isotope production to use low-enriched uranium.
The issue, according to Werner Burkart, is cost: converting the old reactor technology from highly enriched uranium to low enriched uranium. "Most of this moly-99 is produced in aging research reactors; more investment is required," he said.
As the world body with the mandate for the dissemination of nuclear technology for peace and development, the IAEA acts as a liaison, facilitating the transfer of technology among countries for the conversion of Highly Enriched to Low Enriched Uranium, both reactor fuel and target for isotope production.