GC–MS analysis of e-cigarette refill solutions: A comparison of flavoring composition between flavor categories

• Published in: Journal of pharmaceutical and biomedical analysis 2020-09, Vol.188, p.113364-113364, Article 113364
• Main Authors: Krüsemann, Erna J.Z., Pennings, Jeroen L.A., Cremers, Johannes W.J.M., Bakker, Frank, Boesveldt, Sanne, Talhout, Reinskje
• Format: Article
• Language: English
• Subjects: e-Liquids; Electronic cigarettes; Flavor compounds; Flavor ingredients; Flavors; Gas chromatography - mass spectrometry
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/j.jpba.2020.113364

•We identified and quantified flavoring ingredients in 320 e-liquids using GC–MS.•The most prevalent flavorings were vanillin, ethyl butyrate, and cis-3-hexenol.•Based on flavoring prevalence, we distinguished 4 clusters of flavor categories.•Flavoring concentrations varied between e-liquids within a category. Electronic cigarette refill solutions (e-liquids) are available in various flavor descriptions that can be categorized as fruit, tobacco, and more. Flavors increase sensory appeal, thereby stimulating e-cigarette use, and flavoring ingredients can contribute to e-cigarette toxicity. We aim to inform toxicologists, sensory scientists, and regulators by determining flavoring compounds in e-liquids with various flavors, and compare results between flavor categories. Gas chromatography - mass spectrometry (GC–MS) was used to identify 79 flavorings in 320 e-liquids, classified in 15 flavor categories. Ten flavorings highly prevalent in e-liquids according to information from manufacturers were quantified. Flavoring prevalence was defined as the number of e-liquids with the flavoring as percentage of the total number of e-liquids. The method was validated in terms of specificity, linearity, repeatability, recovery, and sensitivity. The mean number of flavorings per e-liquid was 6 ± 4. Flavoring prevalence was highest for vanillin (creamy/vanilla flavor), ethyl butyrate (ethereal/fruity), and cis-3-hexenol (fresh/green). Based on similarities in flavoring prevalence, four clusters of categories were distinguished: (1) fruit, candy, alcohol, beverages; (2) dessert, coffee/tea, nuts, sweets; (3) menthol/mint; and (4) spices, tobacco, and unflavored. Categories from cluster 4 generally had less flavorings per e-liquid than fruit, candy, alcohol, beverages (cluster 1) and dessert (cluster 2) (p < 0.05). Flavoring concentrations varied between e-liquids within the categories. We evaluated flavoring compositions of 320 e-liquids using a simple GC–MS method. Flavoring prevalence was similar within four clusters of typically fresh/sweet, warm/sweet, fresh/cooling, and non-sweet flavor categories. To compare flavoring concentrations between individual flavor categories, additional research is needed.