Comparison of indoor air quality in smoke-permitted and smoke-free multiunit housing: findings from the Boston Housing Authority.

INTRODUCTION: Secondhand smoke remains a health concern for individuals living in multiunit housing, where smoke has been shown to easily transfer between units. Building-wide smoke-free policies are a logical step for minimizing smoke exposure in these settings. This evaluation sought to determine whether buildings with smoke-free policies have less secondhand smoke than similar buildings without such policies. Furthermore, this study assessed potential secondhand smoke transfer between apartments with and without resident smokers.
METHODS: Fine particulate matter (PM2.5), airborne nicotine, and self-reported smoking activity were recorded in 15 households with resident smokers and 17 households where no one smoked in 5 Boston Housing Authority developments. Of these, 4 apartment pairs were adjacent apartments with and without resident smokers. Halls between apartments and outdoor air were also monitored to capture potential smoke transfer and to provide background PM2.5 concentrations.
RESULTS: Households within buildings with smoke-free policies showed lower PM2.5 concentrations compared to buildings without these policies (median: 4.8 vs 8.1 µg/m(3)). Although the greatest difference in PM2.5 between smoking-permitted and smoke-free buildings was observed in households with resident smokers (14.3 vs 7.0 µg/m(3)), households without resident smokers also showed a significant difference (5.1 vs 4.0 µg/m(3)). Secondhand smoke transfer to smoke-free apartments was demonstrable with directly adjacent households.
CONCLUSION: This evaluation documented instances of secondhand smoke transfer between households as well as lower PM2.5 measurements in buildings with smoke-free policies. Building-wide smoke-free policies can limit secondhand smoke exposure for everyone living in multiunit housing.