First of all, the study was performed based on the finding of high levels of benzoic acid in JUUL (about 45 mg/mL or 4.5%). JUUL is a prefilled e-cigarette with very high levels of nicotine (they found 6% nicotine, i.e. 60 mg/mL) which protonates nicotine with the use of acid (benzoic acid). It is unique for JUUL to use so high levels of benzoic acid; the authors mention they tested commercial liquids and found benzoic acid at levels of 0.02-2 mg/mL (0.002-0.2%). Benzoic acid could be transformed to benzene, but the study found NON-DETECTED levels of benzene in JUUL despite the use of 5 seconds puff duration.
