Indoor air quality in waterpipe cafés: exposure level to particulate matter.

Waterpipe is increasingly being used worldwide. Despite waterpipe cafés gaining popularity among Iranian population, there is a paucity of research measuring exposures and assessing the health effects of waterpipe smoke in these places. The objective of the current study was to investigate the exposure to PM10, PM2.5, and PM1 concentrations and risk assessment of PM2.5 exposures in different age groups in the indoor air of waterpipe cafés. The study samples were taken from indoor air of 50 waterpipe cafés in Ardabil, Iran. The PM10, PM2.5, and PM1 concentrations were assessed using a portable GRIMM dust monitors. The mean (±SD) concentrations of indoor air PM10, PM2.5, and PM1 were 765 ± 352, 624 ± 327, and 500 ± 305 μg/m3, respectively. The mean of HQ (hazard quotient) for PM2.5 in all age groups of 16 and older was > 1, which corresponds to an unacceptably high risk for human health. Also, the mean of ELCRs (excess lifetime cancer risk) for PM2.5 in different age groups exceeded the limit value by the USEPA. The results indicated that the PM concentration is significantly influenced by the number of waterpipe smokers, type of ventilation system, and kind of tobacco. Therefore, waterpipe cafés are a potential source for exposure to PM10, PM2.5, and PM1 and increase the risk of respiratory diseases and cardiovascular problems among waterpipe smokers.