The popularity of hookah smoking, in which a fruit-flavored tobacco product is inhaled through a glass pipe, is raising concerns about harmful effects such as cancer and other medical conditions. Hookah smoke contains many of the same carcinogens present in tobacco smoke. There is some indication, in fact, that hookah smoke may be even more dangerous, depending on factors such as how much smoke is inhaled and how deeply.
Toxins and Carcinogens
According to the Centers for Disease Control and Infection (CDC), hookah smoke is at least as toxic as cigarette smoke: A 2015 review of studies looking at the potential toxins in hookah smoke found that it contains 27 known or suspected carcinogens.4
Several of these were found to be in higher concentrations in hookah smoke than in cigarette smoke, including carbon monoxide (from the charcoal that is used to heat the water in a hookah pipie), which can contribute to heart disease; benzene; and high molecular weight polycyclic aromatic hydrocarbons (PAHs) for which levels are higher in hookah smoke than cigarette smoke.5 Other toxins found in both cigarette and hookah smoke include arsenic, cobalt, chromium, and lead.4
Greater Amount of Inhaled Smoke
One reason hookah smoke may be more toxic than cigarette smoke is that more smoke is inhaled. In a typical “session” of water-pipe smoking (roughly an hour), 200 puffs are inhaled versus the 20 puffs ordinarily inhaled in smoking a single cigarette. This translates into a typical hookah session resulting in the inhalation of 90,000 milliliters (ml) of smoke as compared to the 500 to 600 ml of smoke inhaled with a cigarette.
Depth of Inhalation
People tend to inhale hookah smoke more deeply into the lungs than they do cigarette smoke. Although it hasn’t been established that this is significant, it may help to look at changes in lung cancer rates after the addition of filters to cigarettes. Before cigarettes had filters, the smoke was not inhaled as deeply and was more likely to cause a type of lung cancer known as squamous cell carcinoma. This type of lung cancer occurs most often in the large airways entering the lungs (the bronchi) and due to this location, tends to be discovered at an earlier stage of the disease (because it leads to symptoms such as coughing, coughing up blood, wheezing, and frequent infections due to airway obstruction).
With the addition of filters to cigarettes, lung adenocarcinoma became more common. This type of lung cancer often occurs in the periphery of the lungs, and due to this location, is often found in the later stages of the disease.
It is the nicotine in cigarettes that leads to addiction and nicotine is present in hookah smoke just as it is in cigarette smoke. Despite advertising to the contrary, hookah smoke does contain tar as well. It is the process of burning (with cigarettes) or heating (with hookah) which creates tar. In fact, hookah smoking may result in higher exposure to tar as it is smoked for a longer period of time and requires a stronger drag.