Vaporizing cannabis oil at high heats produces a known carcinogen, according to a new study. This increasingly popular way of using cannabis, called ‘dabbing’ uses highly concentrated cannabis oil, and its potency has been the subject of controversy. The Portland State University study found that when a ‘dab’ of highly concentrated cannabis oil was heated and vaporized at very high temperatures, the process produced benzene. This is one of the first studies to confirm a carcinogen in any form of cannabis. Using inexpensive heating methods that don’t have temperature controls increases the likelihood that dabbing will produce benzene. This means that people with lower incomes or lower levels of education are likely at greater risk of exposure, according to one of the study’s authors.