Researchers from 9 Canadian institutions have found that second-hand smoke may trigger symptoms of nicotine dependence in children.

“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,” says senior author Jennifer O’Laughlin of l’Université de Montréal.

The study consisted of 1800 children aged 10 to 12 years old from 29 Quebec schools representing all socioeconomic statuses. Researchers asked questions about symptoms of nicotine dependence and exposure to second-hand smoke in addition to having participants complete questionnaires on their health and behaviors.

“Our study found that 5% of children who had never smoked a cigarette, but who were exposed to second-hand smoke in cars or their homes, reported symptoms of nicotine dependence,” says lead author Mathieu Bélanger, of the Université de Sherbrooke.

“These findings support the need for public health interventions that promote non-smoking in the presence of children, and up hold policies to restrict smoking in vehicles when children are present,” says O’Laughlin.

The study is published in the September issue of the journal Addictive Behaviors.