'Thirdhand' smoke beliefs linked to home smoking bans

You've probably heard of secondhand smoke, the passive exposure to tobacco smoke implicated in the deaths and illnesses of nonsmokers. Smoking bans in workplaces or in bars and restaurants became more likely after a 1986 Surgeon General's report equated such exposure with involuntary smoking.

But what about thirdhand smoke? That's the term for smoke contamination that lingers after the cigarette is stubbed out. Residual toxins remain in the air, on surfaces including clothing, and even in household dust, according to research cited in an article published today in Pediatrics, the journal of the American Academy of Pediatrics.

Researchers led by Dr. Jonathan P. Winickoff of Massachusetts General Hospital point out that children are especially vulnerable to thirdhand smoke exposure because they breathe near, crawl on, play with, touch, and put in their mouths contaminated surfaces. But do their parents believe that breathing air in a room where people smoked the day before poses a danger to their children?

Among 1,478 people who responded to that question in a national survey, about two-thirds of nonsmokers agreed that thirdhand smoke could hurt their children compared to just under half of smokers. When asked about secondhand smoke -- inhaling smoke from a parent's cigarette -- almost all nonsmokers and almost as many smokers agreed it was harmful.

Believing that thirdhand smoke was harmful was linked to home smoking bans, while the same was not true for beliefs about secondhand smoke. As might be expected, nonsmokers were much more likely than smokers to have smoking bans in their homes. Smokers might open windows, turn on fans, or smoke only in certain rooms of the home to protect others from secondhand smoke rather than prohibit smoking altogether, the authors said.

"Emphasizing that thirdhand smoke harms the health of children may be an important element in encouraging home smoking bans," the authors write.