Health Canada also said that many new devices that use X-rays to push thin tubes into arteries and blood vessels have not been sufficiently tested and their efficacy and safety remains unknown.
"In general, these procedures are of benefit to Canadians since they allow a shorter stay in hospital and reduce the need for surgery. However, the risks of cancer and deterministic effects (injuries) are not negligible," the document that was obtained by Ottawa researcher Ken Rubin, said.
The report adds that nearly three million Canadians will have a CT scan of their brain, lungs, joints, stomachs or other organs annually and thousands will have an angioplasty or other X-ray guided procedures for various problems like clogged arteries. While the benefits of these procedures are not disputed, Health Canada says the safety remains a problem.
Dr. Richard Semelka, professor and vice-chair of research in University of North Carolina's department of radiology agreed with the document's findings. "They undergo a CT, but nobody says to them that there is a small but definite risk you could get cancer. And I think that is wrong."
But Dr. Benjamin Chow, a cardiologist at the University of Ottawa Heart Institute, said the risk of cancer was very minimal, "Twenty-five per cent of the population will get cancer -- one in four. So you're increasing their risk of cancer from 25 per cent to 25.001 per cent," he said. "From a medical perspective, we don't think this is a significant increase in risk."