Introduction: Secondhand smoke (SHS) exposure is associated with numerous adverse health effects, including cancer, cardiovascular disease, asthma, respiratory infections, and decreased pulmonary function. This study provides population estimates of SHS exposure among the Canadian nonsmoking population based on self-report and urinary cotinine concentrations.
Methods: The 2007-2009 Canadian Health Measures Survey, a nationally representative cross-sectional survey, collected data from Canadians aged 6-79 years, and it includes self-report and urinary cotinine measures of tobacco smoke exposure (n = 4,455).
Results: An estimated 22% of nonsmokers reported being exposed to SHS every day or almost every day. Of those, 70% of children (6-11 years) and 48% of adolescents (12-19 years) had detectable cotinine levels compared with 23% of adults (20-79 years). An estimated 77% of nonsmokers exposed to SHS only in the home had detectable cotinine levels compared with 11% of nonsmokers exposed to SHS only outside the home. Of those exposed to SHS only in the home, a higher percentage of children (5.1%) had detectable cotinine levels compared with adults (3.1%).
Conclusions: Despite well-known health risks associated with exposure to tobacco smoke, a substantial proportion of the Canadian population continues to be exposed to SHS. Higher percentages of certain subpopulations had detectable cotinine concentrations, including children, adolescents, and those exposed to SHS in the home.