Evaluation of Presence or Absence of α-Tocopherol and α-Tocopheryl Acetate in Various E-Liquids

The presence of α-tocopheryl acetate in e-liquids is linked to EVALI (Electronic Cigarette, or Vaping, product use-Associated Lung Injuries). Typical e-liquids containing flavors and nicotine have a glycerin/propylene glycol carrier and are highly unlikely to contain α-tocopherol or α-tocopheryl acetate. However, the e-liquids containing cannabinoids, most notably tetrahydrocannabinol (THC), may contain α-tocopherol or α-tocopheryl acetate for enhancing the solubility of THC which is a lipophilic compound. For the analysis of α-tocopherol and of α-tocopheryl acetate in e-liquids a new HPLC technique was adopted which has been developed for the analysis of these compounds in tobacco and cigarette smoke and was previously reported. Both UV and MS/MS (MRM mode) were used as detection procedure.

Thirty four e-liquids containing different levels of nicotine were evaluated using this method. None of the e-liquids contained either α-tocopherol or α-tocopheryl acetate. Also, three e-liquids containing cannabidiol (CBD) were analyzed. Two of the CBD containing liquids did not contain α-tocopherol or α-tocopheryl acetate. However, one of these e-liquids did contain α-tocopherol, but the level was low at about 10 μg/g, which is lower than the level of α-tocopherol per smoke of one cigarette (ISO smoking), and significantly lower than the level of α-tocopherol in tobacco.