But at Stanford's nuclear medicine department that day, a patient had missed his appointment. This meant the dose -- which cost the hospital an irretrievable $500 -- had decayed and was now useless. The technician threw the syringe in the trash.
The supply chain's vulnerability, acutely felt during a severe worldwide shortage in 2009 and 2010 when two reactors shut down unexpectedly, has led some doctors to shift to more dependable, but more toxic, imaging agents. "For cardiac imaging, we had to shift to a more expensive agent and expose patients to more radiation," said Dr. Andrei Iagaru, chief of the division of nuclear medicine at Stanford Health Care.
After the worldwide shortage, the volume of nuclear medicine tests went down, and stayed down. "It definitely had an impact on the way many practices run their cardiac stress tests," Iagaru said.
American patients consume nearly half of the world's supply of moly-99. And despite plans to ramp up production in Australia, reactor construction is notoriously tricky. In addition, reactors that are converting for security reasons to low-enriched uranium have lower yields and more waste, according to nuclear scientists.
Concerns about moly-99 shortages heightened in October 2016, when the Canadian government mothballed a reactor in Chalk River, Ontario, that supplied about 40 percent of the American market. The government's decision to shutter the plant was, in part, due to frustration that Canada had had to spend $70 million in 2009 to repair the facility -- in effect, subsidizing the American health care industry. That is a complaint of European governments as well.
William Magwood, director of the Nuclear Energy Agency in Paris, said that moly-99 production at Chalk River "went from being incidental to being the only reason to operate the reactor."
"Canadians didn't want to continue to operate a high-cost reactor to sell isotopes to the U.S.," he said.
Some European governments have begun charging moly-99 producers higher rates to rent reactor time, and prices are expected to rise sharply when governments strip for-profit companies of subsidies originally meant to support academic research.
"How much will get passed on to the health care providers?" said Leah Gannon, senior portfolio executive of radiopharmaceutical distribution sourcing for Vizient, a company that negotiates contracts for hospitals. "Probably almost all of it."
With no source of moly-99 anywhere in North America, American nuclear medicine specialists appointed by the National Academies of Sciences, Engineering and Medicine warned in a 2016 report commissioned by Congress of a more than 50 percent likelihood of another severe shortage in the coming years.