Short supply of molybdenum-99 cited for some delayed or canceled nuclear imaging tests

A recent shut-down of a nuclear reactor in Canada raised concerns for adequate supply of the isotope.

The recent shut-down of a nuclear reactor at Chalk River Laboratories in Canada (a producer of molybdenum-99) caused concern among nuclear imaging specialists.

“Over the years, and including this year, we have had many times where, for one reason or another, the supply gets interrupted or scaled back,” said Ami Iskandrian, MD, a professor of medicine and radiology at the University of Alabama in Birmingham and a member of the Cardiology Today editorial board, said. “We do what we can, such as rescheduling patients or using thallium.”

The decay product of molybdenum-99 (technetium-99m) is the most widely-used radio-isotope in the world for molecular and nuclear diagnostic imaging tests. Nearly two-thirds of the 22.5 million diagnostic radiopharmaceuticals injected into patients in the United States in 2008 were used for cardiac exams. Interruptions in the supply chain of molybdenum-99 can cause physicians to postpone or cancel nuclear imaging tests.

Lantheus Medical Imaging recently announced an agreement with a subsidiary of the South African Nuclear Energy Corporation for the continued manufacture and supply of the isotope. The company said in a press release that other recent interruptions in the global supply chain of molybdenum-99 have been due to reliance on aging or unreliable nuclear reactors, according to the company.

Iskandrian said another possible problem is that the majority of the molybdenum-99 used in the United States is imported from foreign manufacturers.

“There are other suppliers of molybdenum-99 in the world, such as in Europe and Japan,” Iskandrian said. “The real answer, however, is that the United States needs to produce its own and supply the excess to the rest of the world.” – by Eric Raible