The Canadian study suggests that parents who smoke cigarettes around their kids in cars and homes might trigger symptoms of nicotine dependence in children, as they are increasingly exposed to second hand smoke.
"Increased exposure to second-hand smoke, both in cars and homes, was associated with an increased likelihood of children reporting nicotine dependence symptoms, even though these children had never smoked," said Dr. Jennifer O'Loughlin, senior author of the study, a professor at the Universite de Monteal's Department of Social and Preventive Medicine and a researcher at the Centre Hospitalier de l'Universite de Montreal.
The researchers recruited students from 29 Quebec schools as part of AdoQuest, a cohort investigation that measures tobacco use and other health-compromising behaviours.
Some 1,800 children aged 10 to 12 years old, from all socioeconomic levels, were asked to complete questionnaires on their health and behaviours. Researchers also asked questions about symptoms of nicotine dependence and exposure to second-hand smoke.
"Our study found that 5 percent of children who had never smoked a cigarette, but who were exposed to secondhand smoke in cars or their homes, reported symptoms of nicotine dependence," said Mathieu Belanger, the study's lead author and the new research director of the Centre de Formation Medicale du Nouveau-Brunswick of the Universite de Moncton and Université de Sherbrooke.
"These findings support the need for public health interventions that promote non-smoking in the presence of children, and uphold policies to restrict smoking in vehicles when children are present," added O'Loughlin.
The research team included scientists from the Universite de Sherbrooke, the Universite de Moncton, the University of British Columbia, McGill University, Concordia University and the Institut national de sante publique du Quebec.