Some hospital officials in Ontario are questioning the auditor general's concern that CT scans could expose children to unsafe levels of radiation.

In his annual report, Auditor General Jim McCarter said people of all ages could be at risk from excess radiation from CT (computed tomography) scans, but referred to children in particular.

Hospitals do not take enough precautions to ensure patients receive the right dose, McCarter said in his report.

But there is no evidence to support the claim, said Hilary Short, president of the Ontario Hospital Association.

"What the auditor is saying that [with] prolonged exposure to multiple CT scans over a long period of time, then there is a potential long-term risk," said Short. "There are no examples, we have none, and we're not aware of any, nor is the auditor general."

A rigorous system governs diagnostic equipment in hospitals, said Karen Pearson, who is in charge of CT scans at Kingston General Hospital in eastern Ontario.

"There are so many checks and balances in place," said Pearson. "It would be some very unusual circumstance that would ever allow over-radiation to ever occur."

The public should not be worried about the concerns raised by the auditor general, said Michael Bronskill, a medical biophysics professor at the University of Toronto.

Everyone is exposed to small amounts of radiation daily, and the long-term cancer risk from diagnostic machines is low, he said.

A poorly calibrated machine would raise the risk only slightly, even in children, said Bronskill, who suggested changing provincial legislation to allow medical physicists to act as radiation safety officers at hospitals.

"It's a tempest in a teapot," Bronskill said. "Could it be done better? Yes. Would it have a major effect on the health of the population of Ontario? No."

Health Minister George Smitherman said his ministry is working with the OHA and the College of Physicians and Surgeons of Ontario to create universal standards on radiation doses.

With files from the Canadian Press