From wikipedia:
Health Effects
that smoking using a waterpipe poses a serious potential health hazard and is not a safe alternative to cigarette smoking.
The average hookah session typically lasts more than 40 minutes, and consists of 50 to 200 inhalations that each range from 0.15 to 0.50 liters of smoke.[SUP][46][/SUP][SUP][47][/SUP] In an hour-long smoking session of hookah, users consume about 100 to 200 times the volume of smoke of a cigarette. The chemical compositions of cigarette smoke and hookah smoke are different, however, as the workings of the charcoal in the modern hookah causes the tobacco mixture to be heated to a lower temperature, as opposed to the higher temperature in a cigarette where the tobacco is directly burnt. Consequently, the potential health effects of hookah smoke are expected to be very different.[SUP]
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Despite a different chemical composition of the smoke, it is expected that heavy and long term use still has the potential to lead to diseases generally induced by tobacco, notably
chronic obstructive pulmonary disease.[SUP]
[50][/SUP] Mixtures with lighter concentrations or tobacco-free alternatives (e.g. tobamel, tea-leaf, molasses and glycerin-soaked stones) are widely available and aim to reduce the negative effects of tobacco.[SUP]
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A 2008 aetiological study on hookah smoking and
cancer led by a group of Pakistani researchers[SUP]
[52][/SUP] found that overall serum
CEA levels (as a biological marker for cancer) in exclusive hookah smokers, who had been using weight equivalents of up to 60 cigarettes of tobacco in daily sessions for decades, were higher than in non-smokers but substantially lower than those recorded in cigarette smokers considering the same amount of tobacco. The study also concluded that heavy and non-moderate hookah smoking (2–4 daily preparations; 3–8 sessions a day; 2 to 6 hours net daily smoking time) substantially raises CEA levels.[SUP]
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