That news, coupled with the summer’s production problems in Canada and the Netherlands, gave backers of using low-enriched uranium an opportunity to break the decades-long stalemate. “It was fortuitous that the supply interruption occurred and got things moving,” Kuperman says.

Interested parties who often had been at odds—nuclear medicine specialists, national security experts, politicians and scientists–began to collaborate on what became the American Medical Isotopes Production Act. Markey and Rep. Fred Upton, R-Mich., introduced legislation last summer, and the House passed the bill Nov. 5. The measure still requires Senate action and President Obama’s signature to become law.

It would provide $163 million over five years to establish domestic production of molybdenum-99 from low-enriched uranium. It also sets a timeline to phase out highly enriched uranium exports for medical isotope production. And the Obama administration has committed an additional $20 million in funds to speed the conversion

Future production
Foreign producers see the handwriting on the wall. In September, a top Department of Energy official testified that the foreign makers of isotopes have approached the United States for financial and technical assistance in converting to lower-grade uranium.

As for the dire shortages of isotopes predicted this summer, most hospitals around the country fared relatively well, although certain regions, including the Midwest, experienced shortages. Belgium, France and South Africa increased output to meet demand. Doctors ordered doses of TC-99m more efficiently and used alternative isotopes for certain diagnostic tests.

“It was not the huge crisis that we were concerned about,” Graham says.

That doesn’t mean that supply problems won’t crop up again soon, warns Jeffrey Norenberg, executive director of the National Association of Nuclear Pharmacies. Chalk River’s future is uncertain. And things “will go from bad to worse” early next year when the Netherlands reactor begins a scheduled six-month outage, Norenberg says.

He’s hopeful new isotope reactors in Australia and Argentina—which both use low-enriched uranium—will eventually be certified by the U.S. Food and Drug Administration and be able to fill up to 15 percent of U.S. demand for TC-99m.

At Maine Medical Center, Chet Bradbury worries, too. Although supply problems haven’t inconvenienced his patients so far, he says, that may change. “As to what our pharmacy can get, it will be on a week-to-week basis, based on production worldwide.”

Susan Q. Stranahan is a freelance writer who lives in Maine.