Waterpipe (hookah, shisha) tobacco smoking has spread worldwide. Many waterpipe smokers
believe that, relative to cigarettes, waterpipes are associated with lower smoke toxicant
levels and fewer health risks. For physicians to address these beliefs credibly, waterpipe
use and cigarette smoking must be compared directly.
The purpose of this study is to provide the first controlled, direct laboratory comparison
of the toxicant exposure associated with waterpipe tobacco and cigarette smoking.
Participants (N=31; M=21.4 years, SD=2.3) reporting monthly waterpipe use (M=5.2 uses/month,
SD=4.0) and weekly cigarette smoking (M=9.9 cigarettes/day, SD=6.4) completed a crossover
study in which they each smoked a waterpipe for a maximum of 45 minutes, or a single
cigarette. Outcome measures included expired-air carbon monoxide (CO) 5 minutes after
session's end, and blood carboxyhemoglobin (COHb), plasma nicotine, heart rate, and
puff topography. Data were collected in 2008-2009 and analyzed in 2009.
On average, CO increased by 23.9 ppm for waterpipe use (SD=19.8) and 2.7 ppm for cigarette
smoking (SD=1.8), while peak waterpipe COHb levels (M=3.9%, SD=2.5) were three times
those observed for cigarette smoking (M=1.3%, SD=0.5; p's<0.001). Peak nicotine levels
did not differ (waterpipe M=10.2 ng/mL, SD=7.0; cigarette M=10.6 ng/mL, SD=7.7). Significant
heart rate increases relative to pre-smoking were observed at 5, 10, 15, 20, 25, and
35 minutes during the cigarette session and at 5-minute intervals during the waterpipe
session (p's<0.001). Mean total puff volume was 48.6 L for waterpipe use as compared
to 1.0 L for cigarette smoking (p<0.001).
Relative to cigarette smoking, waterpipe use is associated with greater CO, similar
nicotine, and dramatically more smoke exposure. Physicians should consider advising
their patients that waterpipe tobacco smoking exposes them to some of the same toxicants
as cigarette smoking and therefore the two tobacco-smoking methods likely share some
of the same health risks.