Smoking a water-pipe or hookah may be chic, but the carbon monoxide, nicotine, tar and heavy metals contained in the smoke pose often-ignored health threats, researchers say.
The concentration of cancer-causing and addictive substances in tobacco blends smoked in water-pipes can be higher than those found in cigarettes, according to a report published in the medical journal, Pediatrics.
Common for centuries in the Arabian Peninsula, Turkey, India, Pakistan and some regions of China, water-pipe smoking had been in decline in the past century and principally become a habit of older men in bazaar cafes.
But the report cited an upsurge in hookah smoking in recent years with "hookah bars" in major cities. It estimated that more than 100 million people globally smoke a water-pipe on any given day.
In Israel, sharing a water-pipe is a way for the nation's Jewish and Arab youth to mesh two cultures, and a survey of 6000 teenagers found 40% of Jews and 31% of Arabs had smoked a water-pipe.
The tobacco used in hookahs comes in three forms: maasel contains tobacco mixed with honey or molasses, tumbak or ajami is pure tobacco paste, and jurak usually contains fruits or oils. Some smokers add alcohol, hashish or marijuana.
Water-pipe or hookah smoking is known by various names including narghile, aggileh, goza, hubble-bubble, and shisha, and was believed to have originated in India.