Background: Despite accumulating evidence about its adverse health effects, water-pipe tobacco smoking has become very popular among youth. The aim of this study was to compare smoke exposure and the kinetics of exhaled carbon monoxide (eCO) between water-pipe and cigarette smokers under different conditions.
Methods: Using a cross-over study design, changes in eCO and urinary cotinine levels were measured in a cohort of 32 healthy university students after sessions of water-pipe smoking indoors and outdoors.