Roberta Ferrence

Not just ‘a few wisps’: real-time measurement of tobacco smoke at entrances to office buildings

Introduction An unintended consequence of indoor smoking restrictions is the relocation of smoking to building entrances, where non-smokers may be exposed to secondhand smoke, and smoke from outdoor areas may drift through entrances, exposing people inside. Tobacco smoke has been linked to numerous health effects in non-smokers and there is no safe level of secondhand smoke (SHS) exposure. This paper presents data on levels of tobacco smoke inside and outside entrances to office buildings. Methods Real-time air quality monitors were used to simultaneously measure respirable particulate matter (PM2.5; air pollutant particles with a diameter of 2.5 μm or less) as a marker for tobacco smoke, outside and inside 28 entrances to office buildings in downtown Toronto, Ontario, in May and June 2008. Measurements were taken when smoking was and was not present within 9 m of entrances. Background levels of PM2.5 were also measured for each session. A mixed model analysis was used to estimate levels of PM2.5, taking into account repeated measurement errors. Results Peak levels (10 s averages) of PM2.5 were as high as 496 μg/m3 when smoking was present. Mixed model analysis shows that the average outdoor PM2.5 with smoking was significantly higher than the background level (p<0.0001), and significantly and positively associated with the number of lit cigarettes (p<0.0001). The average level of PM2.5 with ≥5 lit cigarettes was 2.5 times greater than the average background level. Conclusions These findings support smoke-free policies at entrances to buildings to protect non-smokers from exposure to tobacco smoke.

Is nicotine dependence related to smokers' support for restrictions on smoking?

OBJECTIVES To examine the relationship between nicotine dependence and attitudes, predicted behaviours and support regarding restrictions on smoking. DESIGN Population-based, computer-assisted, telephone survey of adults in Ontario, Canada using a two-stage stratified sampling design; 1764 interviews were completed (65% response rate) yielding 424 (24%) cigarette smokers, of whom 354 (83%) smoked daily. The Heaviness of Smoking Index was used as a measure of nicotine dependence. MAIN OUTCOME MEASURE Attitudes toward smoking restrictions, predicted compliance with more restrictions, and support for total smoking bans. RESULTS Attitudes favorable to smoking restrictions tended to decrease with increased nicotine dependence, but the associations were not statistically significant after adjusting for demographic variables. Predicted compliance with more restrictions on smoking decreased with higher levels of dependence, as did support for a total ban on smoking in restaurants, workplaces, bingo halls, and hockey arenas. Support for smoking bans in food courts, family fast food restaurants, and bars and taverns did not vary significantly with level of nicotine dependence. CONCLUSIONS Level of nicotine dependence is associated with intended behaviors and support for smoking restrictions in some settings. These results have implications for tobacco control programs and policies.

The Impact of Ontario Smoke-Free Legislation on Secondhand Smoke in Enclosed Public Places

Many studies have evaluated the impact of indoor smoking bans on secondhand smoke (SHS) exposure. No studies have assessed the impact of a smoking ban on SHS in enclosed areas outside separately ventilated, designated smoking rooms (DSRs). This study evaluated the overall impact of the Smoke-Free Ontario Act implemented May 31, 2006, on SHS in bars and coffee shops and the impact of banning DSRs on SHS outside DSRs. Air particulate matter (PM) and carcinogenic particulate polycyclic aromatic hydrocarbons (PPAH) were measured in May 2006 before the ban inside and outside DSRs in Toronto venues (13 coffee shops and 14 bars) that allowed smoking only in DSRs, and in Windsor venues (10 coffee shops and 10 bars) where smoking was allowed in shared spaces. Measurements were repeated 2 months post-ban. Air quality index values (AQIs) were calculated. Mixed model analysis was applied, taking into account measurement errors for repeated measures. Post ban, mean PM and PPAH levels were reduced by 87% (from 494 to 67 mm2/m3) and 94% (from 196 to 11 ng/m3), respectively, inside Toronto DSRs. Mean PM and PPAH levels were reduced by 10% (from 124 to 111 mm2/m3) and 46% (from 45 to 24 ng/m3), respectively, outside Toronto DSRs. In all Windsor venues, mean PM and PPAH levels were reduced by 83% (from 488 to 81 mm2/m3) and 90% (from 107 to 10 ng/m3), respectively. All reductions were statistically significant (p < 0.0001). In Toronto venues, the AQI was reduced from the “very unhealthy” range inside DSRs and the “moderate” range outside Toronto DSRs to the “good” range, and in Windsor venues from the “unhealthy for sensitive groups” range to the “good” range post-ban. Pre-ban PPAH levels including those outside Toronto DSRs may be associated with cardiovascular injury. DSRs did not provide adequate protection from SHS. The Smoke-Free Ontario Act produced a significant and firm reduction in SHS exposure in venues both with and without DSRs.