Second-hand smoke exposure in settings not regulated by the Spanish law

Introduction To assess exposure to second-hand smoke (SHS) in bus stops and markets, settings excluded from the Spanish Law 42/2010 regulating smoking in closed and open public places. Material and Methods Cross-sectional study in Barcelona assessing SHS exposure in 20 bus stops, 8 open markets, and 9 closed for comparison. We measured PM2.5 and vapour-phase nicotine as markers of SHS during 30 min (both in μg/m3), using a SidePak AM510 monitor and a cassette containing a filter treated with sodium bisulphate, respectively. We computed medians and interquartile ranges (IQR) and compared them according to traffic density, evidence of smoking (tobacco smell/butts), presence of smokers, wind speed, and type of bus stop (with/without shelter) or type of market (open/closed). Results Median (IQR) PM2.5 concentration was 13.52 µg/m3 (9.62–17.68 µg/m3) in bus stops, being higher in those with evidence of smoking (14.04 vs. 8.84 µg/m3; p