Source: www.medicalnewstoday.com Author: staff Tobacco use is the leading preventable cause of mortality worldwide and is responsible for the deaths of 6 million people annually. Hookah smoking, a form of tobacco use that employs a partially filled water jar, has come under scrutiny in a new study, which suggests hookah smokers and non-smokers exposed to the smoke have increased uptake of benzene, a substance linked to increased risk of leukemia. Hookah smokers The study is published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research. According to the researchers - led by Nada Kassem, associate director at the Center for Behavioral Epidemiology and Community Health at San Diego State University in California - the World Health Organization (WHO) and the US National Toxicology Program have classified benzene as a Group 1 carcinogen. WHO further report that benzene is carcinogenic to humans, recommending that there is no safe level of exposure. Hookah smoke, however, is a source of benzene exposure and is, therefore, a risk factor for leukemia. The most popular kind of hookah tobacco is known as Moassel, which is sweetened and flavored tobacco that contains about 30% tobacco fermented with molasses and fruits mixed with glycerin and chemical flavors. Kassem and her colleagues note that in the US in 2013, it was reported that 26.6% of male and 23.2% of female college students have used hookah at some point in time. Alarmingly, 8.1% of male and 6.6% of female middle and high school [...]