Even on an outdoor patio, second-hand cigarette smoke can produce air quality comparable to a smoggy day in Los Angeles or even a forest fire, new research contends.
The findings are based on a series of air quality tests performed on Montreal patios.
Ryan Kennedy, a university researcher, said he found poor air quality even there was a breeze and no restrictions blocking the flow of air, such as an awning or umbrella.
"I think what's important is for us to remember that tobacco smoke is a Class A carcinogen, and any level of exposure bears a risk," Mr. Kennedy, based at Johns Hopkins University in Baltimore, Md., said in an interview Saturday.
Anti-tobacco advocates are hoping the findings help make the case for a patio smoking ban in Quebec, and across the country.
Several provinces have already banned smoking on patios, including Newfoundland, Nova Scotia, and Alberta. Yukon has also introduced a ban, along with Ottawa and a number of municipalities on Vancouver Island and in the lower mainland of British Columbia.
Quebec is among the provinces that has so far resisted going that route.
Montreal, in particular, is well-known for its sidewalk cafes and bars.
Bar owners are worried a ban would mean losing patrons, just as they did after smoking was banned inside restaurants and bars.
Peter Sergakis, the head of the province's bar owner association, said he's skeptical of the study and plans to conduct his own tests.
"It doesn't make sense," said Mr. Sergakis, who owns several Montreal bars.
"Everybody made terrasses so our customers can go out and smoke. And now they're telling us they can't smoke there. What's going to be next — they can't smoke on the sidewalk?"
Flory Doucas, a spokeswoman for the Quebec Anti-Tobacco Coalition, said businesses will need to adapt.
Ms. Doucas said wait staff are especially vulnerable under the current rules.
"In the case of workers, they are walking back and forth across these areas filled with smoke. This is a health issue," she said.
Mr. Kennedy said some of the air quality measurements he recorded on patios were on par with with levels recorded in Kelowna, B.C. when forest fires ravaged the region a few years ago.