Composition and chemical health hazards of the most common electronic cigarette liquids in nine European countries.

Background: The aim of the present study was to identify the composition and reported chemical health hazards of the most common electronic cigarette liquids (e-liquids) in nine European Union (EU) Member States (MS) prior to adoption of the Tobacco Product Directive (TPD).

Materials And Methods: Within the Horizon2020, EUREST-PLUS study, 122 of the most commonly sold e-liquids in 9 EU MS were randomly selected and purchased. A quantitative and qualitative chemical analysis was performed using a previously validated based gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry method. The most commonly detected compounds were then divided according to the Danger Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and Warning GHS codes.

Results: Within our qualitative analysis, 171 different compounds were detected. Discrepancies in measured versus reported nicotine concentration were identified. Forty-one (85.4%) of the most commonly detected compounds were registered with Warning GHS codes, 11 with Danger GHS codes and 9 with both codes. Of the total number of the detected compounds, 293 were attributable to fruits flavor, followed by tobacco flavor (204), nonalcoholic drinks (n = 64), desserts-sweets (n = 50), menthol - mint (n = 42) and alcohol (n = 39). Menthol which is classified as a strong irritant to skin and eye was the most frequently detected compound.

Conclusion: A large plethora of compounds with varying warning codes was identified in e-cigarette samples. The systematic monitoring and chemical evaluation of e-liquids are warranted, so as to ensure consumer protection.