Secondhand Tobacco Smoke Exposure in Open and Semi-Open Settings: A Systematic Review

Table 2. Main characteristics of reviewed studies from before September 2012 assessing outdoor SHS exposure in non-hospitality settings.
Reference, location Study design: venue type, and sample size SHS marker Potential confounders SHS marker concentration Background concentration (control)
Presence of smokers Absence of smokers
cig, cigarettes.
CARB 2005, California, USA Observational: an airport, a junior college campus, a public building, an office complex, and a park Airborne nicotine No. of cigarettes smoked, wind speed, and direction Range, 0.013–3.1 µg/m3   Range, 0.009–0.12 µg/m3
Repace 2005, Baltimore, USA Experimental: various locations on the UMBC campus (outdoors and indoors) PM3.5 and PAH Distances, number of smokers, and wind conditions Range, 100–150 µg/m3 outdoors in proximity to smokers    
Boffi et al. 2006, Copenhagen, Denmark Observational: in a car park, inside a nonsmoking conference center, outdoors in front of the conference center, with smokers under a roof, along the motorway, and inside a Copenhagen restaurant where smoking was allowed PM2.5 None Outside in front of a conference center: 17.8 µg/m3. Along the motorway: 4.6 µg/m3 Car parking area: 6.0 µg/m3. Inside a conference center: 3.0 µg/m3 5.7 µg/m3
Klepeis et al. 2007, California, USA Observational and experimental: 10 outdoor public places including parks, sidewalk cafés, and restaurant and pub patios. Results provided for hospitality venues and other settings combined PM2.5 Wind conditions, source proximity, and no. of cigarettes Overall mean: 30 µg/m3. Maximum: 1,000 µg/m3 at distances within 0.5 m    
Wilson et al. 2007, New Zealand Observational: 10 transportation settings, 9 non-hospitality indoor settings, and 6 non-hospitality outdoor settings. Also in this study: 34 pubs, restaurants, and bars and 6 outdoor smoking areas of bars and restaurants PM2.5 No. of people in room/area and no. of lit cigarettes among occupants   Transportations settings (= 10): 13 µg/m3. Non-hospitality indoors (= 9): 3 µg/m3. Non-hospitality outdoors (= 6): 7 µg/m3 14 µg/m3
Kaufman et al. 2010b, Toronto, Canada Observational: entrances to 28 office buildings both indoor and outdoor PM2.5 No. of cigarettes, wind direction and strength, and distance from the nearest lit cigarette to the monitor Overall median outdoors: 11 µg/m3 (1–4 cig); 16 µg/m3 (≥ 5 cig). Maximum: 496 µg/m3. Overall median indoors: 6 µg/m3 (1–4 cig); 4 µg/m3 (≥ 5 cig) Overall median outdoors: 8 µg/m3. Overall median indoors: 5 µg/m3 8 µg/m3
Parry et al. 2011, New Zealand Observational: streets (no. of samples not indicated) PM2.5 No. of smokers, smoking proximity, and coverage Overall mean: 14.2 µg/m3. Maximum: 186.0 µg/m3 Overall mean: 5.9 µg/m3  
Sureda et al. 2012, Barcelona, Spain Observational: 47 public building main entrances (both outdoors and indoors) PM2.5 and airborne nicotine No. of lit cigarettes, coverage, and distance to roadways Overall PM2.5 concentration outdoor: 17.16 µg/m3. Overall PM2.5 concentration indoor: 18.20 µg/m3. Nicotine concentration in 28 main entrances outdoors: 0.81 µg/m3. Maximum value PM2.5 (outdoor): 128.44 µg/m3 Overall PM2.5 concentration Control point indoor: 10.40 µg/m3 PM2.5 concentration: 13.00 µg/m3
Wilson et al. 2011, New Zealand Observational: 15 inside public buildings, 15 inside transportation settings, and 22 various outdoor street/park settings. Also in this study: 20 outdoor smoking areas of hospitality venues, 13 inside bars adjacent to outdoor smoking areas, 10 pubs/sports bars, 18 bars, 9 restaurants, and 5 cafés PM2.5 None   Inside non-hospitality settings (= 30): range, 2–13 µg/m3. Non-hospitality outdoor settings: range, 2–11 µg/m3 11 µg/m3