Characterization of the chemical landscape of commercial e-cigarette liquids and aerosols by liquid chromatography-high resolution mass spectrometry
Publication date: October 5, 2021
Available at: https://doi.org/10.1021/acs.chemrestox.1c00253
DESCRIPTION
The rapid increase in the use of electronic cigarettes (e-cigs) has raised questions about exposure to chemicals that may result from vapor inhalation, but while previous studies have focused on known toxins and comparisons to those present in traditional cigarettes, few have investigated the unknown compounds and transformation products formed during the vapor inhalation process.
The objective of this study was to apply liquid chromatography-high resolution mass spectrometry (LC-HRMS) and chemical fingerprinting techniques for the characterization of e-liquids and aerosols from a selection of popular e-cigarette products.
Four popular e-cig products were used to perform non-targeted and quantitative analyses of the generated tobacco flavored e-liquids and aerosols.
The aerosols were collected using a condenser and analyzed in solution along with the e-liquid by LC-HRMS.
The number of compounds detected increased from e-liquid to aerosol in three of the four commercial products, as did the percentage of condensed hydrocarbon-like compounds associated with combustion.
Kendrick's mass defect analysis suggested that some of the additional compounds detected in the aerosols belonged to a homologous series resulting from the decomposition of high molecular weight compounds during vapor inhalation, lipids in inhalable aerosols were associated with severe respiratory effects, and lipid-like compounds were observed in the aerosols and the e-liquids analyzed.
Six potentially hazardous additives and contaminants, including the industrial chemical tributylphosphine oxide and the irritant caffeine, were identified and quantified in the analyzed e-cigarette liquids and aerosols.
These findings show the potential of non-targeted LC-HRMS to identify previously unknown compounds and compound classes in e-cigarette liquids and aerosols.
