A central Newfoundland hospital is facing a serious shortage of medical isotopes, and that means some patients will have to wait longer for some medical tests, officials said.

"Our isotope shipment is projected to be about one-third of what it normal is," said Wayne St. Onge, the director of diagnostic imaging at the James Paton Memorial hospital in Gander.

"We are not going to be able to start cleaning up our backlog, let alone dealing with our day to day demands."

Radioactive isotopes are required for some diagnostic tests, including scans for cancer and heart and lung disease.

Gander's nuclear medicine unit, which has been closed for renovation, is scheduled to reopen later this month.

When it re-opens, St. Onge said, the unit will only be able to handle about half the 250 tests it usually performs in a month, which means only emergency scans will be done.

The hospital in Gander had been getting isotopes for medical scans from the Chalk River nuclear reactor in Ontario, which produced a third of the world's supply until May when it was closed indefinitely for repairs.