Canadian clinics still have to wait for medical isotopes because a fledgling Australian nuclear reactor isn't yet making enough isotopes to cover for a downed Canadian reactor that used to produce one-third of the world's supply.

Doctors said Australia's OPAL reactor could still be a few months away from running at full speed.

"I've been told unofficially about two months, two to three months," said Dr. Christopher O'Brien, head of the Ontario Association of Nuclear Medicine. "So, some time mid-fall."

That's longer than first hoped.

Five reactors built a half-century ago supply most of the world's isotopes, which are used to diagnose cancer and heart ailments.

Health Canada and the U.S. Food and Drug Administration, in anticipation of the Australian reactor getting up and running sooner than expected, approved isotopes from OPAL as safe to use in June.

Around the same time, Natural Resources Minister Lisa Raitt told the House of Commons the Australian reactor would start making isotopes more quickly than first thought.

And Lantheus Medical Imaging, a Massachusetts-based company that supplies clinics with "generators" used in medical imaging, said recently it expected to receive isotopes from the Australian reactor starting this month.

The company said it expected shipments to begin around now and ramp up over the next few months.

But O'Brien said production problems seem to have slowed delivery.

"They're having volume-of-production issues," he said.

"They have to get their processing unit up to speed to produce more than they have been … So it's a matter of just getting more in the pipeline."

No one from the Australian Nuclear Science and Technology Organization, which operates the OPAL reactor, was immediately available to comment.

Reactor isn't making enough isotopes

Natural Resources Canada said the Australian reactor isn't making enough isotopes yet to ship to Canada.

"Australia is producing isotopes, but not enough for export yet," spokeswoman Micheline Joanisse said.

The head of the Canadian Association of Nuclear Medicine said the Australians warned Canadian doctors in June they had limited ability to refine the raw isotopes from the reactor.

Dr. Jean-Luc Urbain said that's what has really slowed things down.

"My common sense is telling me that they have issues there for their own supply," he said.

"It's likely unlikely that they'll be able to help anybody else."

Atomic Energy of Canada Ltd.'s reactor at Chalk River, Ont., used to make a third of the world's supply.

But the Crown corporation, which the Conservative government plans to break up and sell off, shut down its 52-year-old reactor in May after finding a radioactive water leak.

So it has fallen to the four remaining reactors — and eventually the Australian facility — to pick up the slack.

A Dutch reactor that also makes a third of the world supply of isotopes had increased its output until it was shut down in July for a month of maintenance.

A smaller Belgian reactor is now shouldering the load until its Dutch counterpart is restarted later this month.

The two-year-old Australian reactor would have helped ease the burden on its aging peers.

O'Brien said an August start-up may have been wishful thinking.

"That was a pie in the sky hope," he said. "Some things take a little longer than anticipated."