Determination of Propylene Glycol and Glycerol in Plasma and Urine - Exposure Assessment in E-cigarette Users Compared to Other Nicotine Product User Groups
Propylene glycol (PG) and glycerol (G) are the main e-liquid constituents and of utmost interest to differentiate between e-cigarette users and other nicotine product users as well as non-users. Therefore, a sensitive LC-MS/MS method for the quantification of PG and G in urine and plasma was developed. PG levels in urine and plasma were significantly elevated in e-cigarette users compared to other nicotine product user groups and non-users. In addition, the PG excretion in urine strongly correlates to the vaping behavior. PG is therefore a suitable biomarker of exposure to differentiate e-cigarette users from other nicotine product user groups including smokers and non-users.