Policy effects of secondhand smoke exposure in public places in the Republic of Korea: evidence from PM2.5 levels and air nicotine concentrations.

OBJECTIVE The purpose of this study was to evaluate secondhand smoke (SHS) exposure inside selected public places to provide basic data for the development and promotion of smoke-free policies. METHODS Between March and May 2009, an SHS exposure survey was conducted. PM2.5 levels and air nicotine concentrations were measured in hospitals (n=5), government buildings (4), restaurants (10) and entertainment venues (10) in Seoul, Republic of Korea, using a common protocol. Field researchers completed an observational questionnaire to document evidence of active smoking (the smell of cigarette smoke, presence of cigarette butts and witnessing people smoking) and administered a questionnaire regarding building characteristics and smoking policy. RESULTS Indoor PM2.5 levels and air nicotine concentrations were relatively higher in monitoring sites where smoking is not prohibited by law. Entertainment venues had the highest values of PM2.5(μg/m3) and air nicotine concentration(μg/m3), which were 7.6 and 67.9 fold higher than those of hospitals, respectively, where the values were the lowest. When evidence of active smoking was present, the mean PM2.5 level was 104.9 μg/m3, i.e., more than 4-fold the level determined by the World Health Organization for 24-hr exposure (25 μg/m3). Mean indoor air nicotine concentration at monitoring sites with evidence of active smoking was 59-fold higher than at sites without this evidence (2.94 μg/m3 vs. 0.05 μg/m3). The results were similar at all specific monitoring sites except restaurants, where mean indoor PM2.5 levels did not differ at sites with and without active smoking evidence and indoor air nicotine concentrations were higher in sites without evidence of smoking. CONCLUSION Nicotine was detected in most of our monitoring sites, including those where smoking is prohibited by law, such as hospitals, demonstrating that enforcement and compliance with current smoke-free policies in Korea is not adequate to protect against SHS exposure.