Smoking has been banned in workplaces, restaurants and theatres, leaving the great outdoors as the next frontier for anti-smoking campaigns.

"People understand the concept of air pollution, that it may be everywhere," said Roberta Ferrence of the Ontario Tobacco Research Unit and the Centre for Addiction and Mental Health in Toronto. "Somehow [with] second-hand smoke outdoors they feel it's magically whisked away, and it isn't."

Newfoundland and Labrador, and Nova Scotia are working on provincewide bans on smoking on restaurant patios, which is already the law in 16 municipalities across Canada.

The governments have acted although there is little published research on levels of outdoor second-hand smoke or its health implications.

Ferrence's colleague, Pam Kaufman of the Ontario Tobacco Research Unit, points to other reasons to ban or reduce outdoor smoking. "Studies have shown that with restrictions, people are more likely to quit and possibly cut down on the amount that they smoke, even if they don't quit."

For Filip Palda, an economist and senior fellow at the Fraser Institute, the move to restrict or ban smoking outdoors is less about protecting people's health than preaching.

"It's a big business, the anti-tobacco lobby gets a lot of government funding," said Palda. "I'm not saying this in a cynical way, but where there's funding to study something and even to repress it, there will be people who come to take the funding."

The lobbyists' activities are so intense that Palda questions why they don't seek to outlaw smoking altogether. Some smokers lighting up on a sidewalk outside a hospital in Halifax asked the same question.

For their next move, anti-tobacco advocates say they want governments to address what they consider a form of child abuse: parents who smoke in their own cars or homes with children present.