Abstract
Air pollutants generated by indoor and outdoor sources adversely affect indoor air quality in many microenvironments. Exposure to indoor air pollutants such as hazardous volatile organic compounds (VOCs), particulate matter with diameters less than 2.5m (PM2.5) and 1m (PM1), and oxocarbons (e.g. CO and CO2) is of great concern to policy makers and environmental authorities due to their adverse impact on public health. Indoor air pollution from smoking tobacco using a waterpipe has been a worldwide public health challenge due to its toxic, carcinogenic and cardiovascular effects. This study investigates the release of PM2.5, PM1, CO2, CO and 72 VOCs to assess the indoor air quality during waterpipe tobacco smoking in a controlled microenvironment and a public cafe. Particulate matters, CO and CO2 were measured using an OSIRIS instrument, a 3M EVM-7, and a CO2 meter, respectively. The VOCs were sampled using pre-evacuated silicon-coated stainless-steel canisters with a 6-l capacity and analysed by an Agilent gas chromatograph with an Entech cryogen system following the US EPA Compendium Method (TO15). All measured pollutants in the controlled microenvironment showed increasing concentrations during the waterpipe smoking session with PM2.5, PM1, CO2 and total VOC contents reaching 31.4, 26.6, 142 and 38.4%, respectively, above their respective background concentrations. CO showed a build-up rate of 0.6mgm(-3)min(-1) in the controlled microenvironment, reaching 16mgm(-3) at the end of the session. In the public waterpipe cafe, the maximum hourly concentrations of PM1, PM2.5, CO and CO2 reached 27 g m(-3), 92 g m(-3), 49.5 mg m(-3) and 3244 mg m(-3), respectively. These optimum values corresponded to the number of smokers present at the cafe late at night. Overall, the public waterpipe cafe had a higher concentration of pollutants compared with the controlled microenvironment due to the number of waterpipes used in the cafe. These results will provide exciting insight into waterpipe emissions in real-world settings.