People who smoke tobacco through a water pipe, also known as a hookah, are still exposing themselves to a harmful mix of toxins, according to a small new study.
Researchers from the University of California, San Francisco (UCSF), cautioned that water pipes are not less harmful than cigarettes. And those who use a water pipe appear to face higher levels of carbon monoxide and benzene, which has been linked to increased risk for leukemia.
"People want to know if it is a lesser health risk if they switch from cigarettes to smoking a water pipe on a daily basis," Peyton Jacob III, a UCSF research chemist at San Francisco General Hospital and Trauma Center, said in a university news release. "We found that water pipe smoking is not a safe alternative to cigarette smoking, nor is it likely to be an effective harm-reduction strategy."
Increased risk of cancer
In addition, Dr. Neal Benowitz, a UCSF tobacco researcher at San Francisco General Hospital and Trauma Center, pointed out that "if you are smoking from a hookah daily, you are likely to be at increased risk for cancer."
The study involved eight men and five women who have smoked cigarettes and also have experience using water pipes. The participants smoked an average of three water pipe sessions daily -- the equivalent of 11 cigarettes per day. Because people metabolise toxic substances differently, the researchers had the participants smoke a water pipe and cigarettes on different days.
After analysing the participants' urine, the investigators found that using a water pipe doubled the levels of a benzene byproduct.
The participants' breath was also tested over 24 hours. The study revealed that carbon monoxide levels were two and a half times higher after water pipe use than cigarette smoking.
Although intake of nicotine is less among water pipe users, the researchers said, they are smoking more than just tobacco.
"You're basically burning a charcoal briquette on top of the tobacco, and most of what you're smoking is a moist fruit preparation, which is mixed with the tobacco," Benowitz said. "It smells good and it tastes good."
But, Jacob said, "In addition to delivering toxic substances from the charcoal and tobacco, the heat causes chemical reactions in the mixture, which produce toxic volatile organic compounds and polycyclic aromatic hydrocarbons (PAHs). Some PAHs are highly carcinogenic and can cause lung cancer."
A 2009 U.S. survey found three in 10 university students had smoked tobacco from a water pipe at least once. Research also showed that water pipe use is more common among white students, men, and fraternity and sorority members.
The study was published online recently in the journal Cancer Epidemiology, Biomarkers & Prevention.
The U.S. Centers for Disease Control and Prevention has more about water pipes.