A Health Canada task force is working out plans to bring in new, tighter guidelines on radon levels in homes - a move critics say should have happened more than 20 years ago.
One of Canada's top radiation experts says the department ignored a warning in the mid-1980s that the country needed a tougher guideline on radioactive radon seeping into homes, leading to thousands of needless premature deaths from lung cancer.
Fergal Nolan, president of the Radiation Safety Institute of Canada, said he asked Health Canada in 1986 to adopt the same strict standard on acceptable radon levels in homes as had been set that year by the U.S. Environmental Protection Agency, but the federal government took no action.
Instead, Health Canada set a guideline two years later that was more than four times as permissive as the U.S. level. The amount of radon considered acceptable for Canadians to be exposed to in their homes would cause damage equal to that of smoking about a pack of cigarettes a day.
"We said to them they should adopt the U.S. guideline, that the guideline they had in Canada was insufficient," Mr. Nolan said in an interview.
"I don't think the Health Canada group took seriously the risk to people's lives; they didn't take seriously other people's assessments. I think they were too complacent about it."
Earlier this year, Health Canada, with little fanfare, changed its view on the dangers of radon. It issued a report proposing the country set a far more rigorous regulatory level, nearly as low as the one in the United States and similar to one prevailing in much of Europe.
The report also estimated that about 10 per cent of lung-cancer deaths are from radon exposure in the home, making it the second leading cause of the deadly illness after smoking.
The radiation safety institute reviewed health statistics for lung cancer from 1986 onward, including a projection for fatalities this year. Using the Health Canada estimate, it concluded the country had 32,833 premature deaths from radon over the period. A significant portion of those deaths could have been avoided, as the department's previous guideline is associated with an approximate doubling of lung-cancer risk, compared with the proposed stricter guideline.
"I think it's unconscionable that this was neglected for so long," Mr. Nolan said.
A federal-provincial working group is now planning the implementation of the new guideline.
Health Canada disputes Mr. Nolan's statement that it failed, in the 1980s, to accurately assess the dangers posed by radon. In an e-mail, the department said its proposal to change the guideline was based on new research conducted in 2004 and 2005 that conclusively established the link between residential radon exposure and lung cancer.
When the existing guideline was adopted in 1988, "there was no direct evidence of lung cancer causation by exposure to radon at levels commonly found in homes. It was known only that exposures to radon levels above [the Canadian guideline]in uranium mines was a factor in lung cancer," Health Canada said.
Mr. Nolan, however, contends the research in 2004 and 2005 was not new because it only pooled results from about 20 previous studies on radon to quantify residential hazards. "These were studies that really confirmed the prudential judgment taken in the early eighties by both European countries, Germany, Sweden, and others and by the U.S. [Environmental Protection Agency]" he said.
The institute, based in Toronto and Saskatoon, is a non-profit organization that promotes radiation safety and was established to help deal with the high incidence of lung cancer caused by radon in the uranium-mining industry in Ontario. It was established through joint funding from the federal and Ontario governments, and the mining industry.
Health Canada had a representative on the institute's board in the 1980s, when Mr. Nolan said he asked the department's radiation protection bureau to consider the U.S. standard for Canada. He said he got nowhere with Health Canada.
Mr. Nolan said the department's attitude at the time was that it knew more about radon than U.S. officials.
He cited one of the institute's newsletters from 1986, in which the head of Health Canada's radiation protection bureau was quoted ridiculing U.S. moves against radon, dismissing the U.S. Centers for Disease Control and Protection as "not experts on radiation. I don't think they have a sufficient understanding of what it's all about."
After being rebuffed, the institute began applying the more restrictive U.S. guideline in its radon testing program in Canada because it viewed Health Canada's position as a health hazard.
The view that the department should have done more to protect Canadians from radon is shared by others.
Ontario's representative on an intergovernmental committee that came up with the proposed radon standard, Arthur Scott, said he believes federal regulators failed to move aggressively against radon because they feared such an effort would divert money and attention from the link between smoking and lung cancer.
"There was some division of opinion in Health Canada on whether the standard was appropriate or not," he said.
He said Health Canada's limit was developed to show the level at which a home was so polluted by radon it "was dangerous" and required remedial action, while U.S. regulators were trying to set a level that signified a home was safe to live in.
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