Hookah's hidden harm: Unsafe exhaled CO levels after visiting hookah cafés

Introduction: Dangers of hookah use are increasingly documented, including case reports of carbon monoxide (CO) poisoning from consumption.  This pilot study sought to assess the uptake of CO among hookah users and non-users in hookah cafés.

Methods: Personal exhaled carbon monoxide was assessed using a Bedfont Scientific Ltd. Micro Smokerlyzer Breath CO monitor.  The CO monitor was zero-calibrated before each use and one or two researchers used the CO monitor to measure personal, exhaled CO pre- and post- patronizing a hookah café.  When two researchers were available for data collection, one researcher smoked hookah and one did not.  Neither researcher is a consumer of cigarettes.  Ambient carbon monoxide levels and particulate matter were also assessed.

Results: The mean boost in exhaled carbon monoxide during hookah smoking sessions (n=6) was 20.3ppm (3.8% COHb), while the mean boost in exhaled carbon monoxide for a non-smoker in a hookah café environment (n=4) was 3.5ppm (1.3% COHb).  Mean ambient carbon monoxide levels in the venues were 22ppm, and mean ambient particulate matter measured 701 µg/m³.  Mean time spent in the venues was 58 minutes.

Conclusions:  Hookah use is associated with significant CO uptake, and many users may be unaware of the related health risks.  Non-users within the hookah café environment are exposed to CO, this suggests that employees and entertainers at these venues (bellydancers, DJs, etc.) are also subject to health risks.  Future research is warranted on the uptake of carbon monoxide among both hookah users and non-users in venues where hookah is smoked.