Gas Chromatography-Tandem Mass Spectrometry Method for the Selective Detection of Glycols and Glycerol in the Liquids and aerosols of E-Cigarette, or Vaping, Products.

Introduction:
This text describes a study that developed and validated a method for detecting and quantifying certain chemicals in e-cigarette liquids and aerosols using gas chromatography-tandem mass spectrometry. The study aimed to determine the specificity, accuracy, linearity, limits of detection, matrix effects, precision, and ruggedness/robustness of the method. The method was then applied to the analysis of e-cigarette products associated with the 2019 outbreak of e-cigarette, or vaping, product use-associated lung injury (EVaLI).

Key points:

* The study developed a method for detecting and quantifying propylene glycol (PG), glycerin (GLY), ethylene glycol (EG), and diethylene glycol (DEG) in e-cigarette liquids and aerosols.
* The method was validated and found to be specific, accurate, linear, and precise, with limits of detection of 0.0109 mg for PG, 0.0132 mg for GLY, 0.250 µg for EG, and 0.100 µg for DEG.
* The method was applied to the analysis of 141 e-cigarette products associated with the EVaLI outbreak, and no products were found to contain glycol contaminants above the recommended maximum residue safety limit.
* The study found typical levels of PG and GLY in nicotine-containing products, CBD products, and products with neither nicotine nor CBD.
* The study also found that inhaled vitamin E acetate has been strongly linked with the EVaLI outbreak.
* The method can be used to ensure e-cigarettes containing PG/GLY mixtures comply with USFDa and USP standards.
* The study demonstrated the versatility of the method by extending its applicability to oil-based e-cigarettes.

Main message:
The study describes the development and validation of a sensitive and specific method for detecting and quantifying PG, GLY, EG, and DEG in e-cigarette liquids and aerosols. The method was applied to the analysis of e-cigarette products associated with the EVaLI outbreak and found no products with glycol contaminants above the recommended safety limit. The study highlights the importance of monitoring e-cigarette products for harmful chemicals and the potential of the developed method for regulatory compliance and safety assessment.

Pérez JJ, Watson Ch, Blount BC, Valentín-Blasini L. Gas Chromatography-Tandem Mass Spectrometry Method for the Selective Detection of Glycols and Glycerol in the Liquids and aerosols of E-Cigarette, or Vaping, Products. Frontiers in chemistry. 2021;9:709495. doi:10.3389/fchem.2021.709495