Trends in adult exposure to secondhand smoke in vehicles: Findings from the 2009-2012 Canadian Tobacco Use Monitoring Survey

Introduction: A growing number of jurisdictions have implemented smoke-free vehicles when children are present due to the substantial health effects of secondhand smoke (SHS). Prior studies on the prevalence of SHS exposure in vehicles have mainly focused on adolescents. This study examined the prevalence and socio-demographic correlates of SHS exposure in vehicles among Canadian adults. Methods: A repeated cross-sectional data on youth and adult data were drawn from the 2009-2012 Canadian Tobacco Use Monitoring Survey (. n=. 58, 195). Multivariable logistic regression analysis was used to examine the socio-demographic correlates of exposure to SHS in vehicles. Results: Overall, 19% in 2009 and 18% in 2012 of adults reported SHS exposure in vehicles in the past month. Disparities in the SHS exposure prevalence were observed, with a higher SHS exposure among current smokers, former smokers, males, younger adults, living in a household with smoking-related exposure, and those with less education. The multivariable analyses showed significant associations between socio-demographic characteristics and SHS exposure. Higher odds SHS exposure was found for those younger (aged 20-24, OR. =. 16.27, CI. =. 11.09-23.88; 25-44, OR. =. 6.12, CI. =. 4.14-9.06; 45-64, OR. =. 2.79, CI. =. 1.95-4.02) compared to those aged 65 and over. Likewise, those with less education had greater odds of SHS exposure. Conclusions: Findings suggest that adults SHS exposure is high, especially for young adults and those with less education. Adult passengers may need protection from SHS given that no level of SHS exposure is safe.