OTTAWA - The Dutch are bracing for the worst if the world is without its two top sources of medical isotopes next year.

That scenario became more likely last week after Canada's nuclear agency said it will take longer than planned to repair the leaky reactor in Chalk River, Ontario.

An aging Dutch nuclear reactor is scheduled for lengthy maintenance work next spring.

That's the earliest its downed Canadian counterpart is expected back up and running.

The two reactors built a half-century ago supply the bulk of the isotopes used to diagnose cancer and heart ailments.

Government, industry and doctors in the Netherlands have formed a task force to prepare for what is being called the worst-case scenario.

Isotopes have been in short supply since the Chalk River facility closed last May, leaving doctors to make do with an erratic supply of medical isotopes.