Indoor secondhand tobacco smoke emission levels in six Lebanese cities

BACKGROUND To date, Lebanon has failed to enact comprehensive clean indoor air laws despite ratification of the Framework Convention on Tobacco Control (FCTC), which calls for the protection of non-smokers from exposure to secondhand tobacco smoke (SHS). Complicating the problem of SHS exposure in Lebanon is the widespread use of the tobacco water-pipe. While most research on SHS has involved cigarette smoking as a source of emissions, other sources, including tobacco water-pipes, may be an important contributor. METHODS PM(2.5) concentrations (microg/m(3)) were measured in a sample of 28 public venues located in six major Lebanese cities. Active smoker density (number of smokers/100 m(3)) was calculated for both water-pipe and cigarette smokers. Venues were then categorised as having higher density of water-pipe smokers or higher density of cigarette smokers, and resultant emission levels were compared between the two groups. RESULTS Cigarette and water-pipe smoking was observed in 14 venues, while cigarette smoking only and water-pipe smoking only were found in 12 venues and one venue, respectively. Among all smoking-permitted venues, the mean PM(2.5) concentration was 342 microg/m(3). Venues with a higher density of water-pipe smokers (n =14) showed a similar median PM(2.5) concentration (349 microg/m(3)) compared with venues with a higher density of cigarette smokers (n =13; 241 microg/m(3); p=0.159). The mean PM(2.5) concentration in the single venue with a voluntary smoke-free policy was 6 microg/m(3). CONCLUSIONS Despite ratification of the FCTC in 2005, both cigarette and water-pipe smoking are commonly practised in enclosed public places throughout Lebanon, leading to unsafe levels of indoor particulate pollution. Smoke-free policies are needed in Lebanon to protect the public's health, and should apply to all forms of tobacco smoking.