Comprehensive overview of common e-liquid ingredients and how they can be used to predict an e-liquid’s flavour category

Abstract

Objectives Flavours increase e-cigarette attractiveness and use and thereby exposure to potentially toxic ingredients. An overview of e-liquid ingredients is needed to select target ingredients for chemical analytical and toxicological research and for regulatory approaches aimed at reducing e-cigarette attractiveness. Using information from e-cigarette manufacturers, we aim to identify the flavouring ingredients most frequently added to e-liquids on the Dutch market. Additionally, we used flavouring compositions to automatically classify e-liquids into flavour categories, thereby generating an overview that can facilitate market surveillance. Methods We used a dataset containing 16 839 e-liquids that were manually classified into 16 flavour categories in our previous study. For the overall set and each flavour category, we identified flavourings present in more than 10% of the products and their median quantities. Next, quantitative and qualitative ingredient information was used to predict e-liquid flavour categories using a random forest algorithm. results We identified 219 unique ingredients that were added to more than 100 e-liquids, of which 213 were flavourings. The mean number of flavourings per e-liquid was 10±15. The most frequently used flavourings were vanillin (present in 35% of all liquids), ethyl maltol (32%) and ethyl butyrate (28%). In addition, we identified 29 category-specific flavourings. Moreover, e-liquids' flavour categories were predicted with an overall accuracy of 70%. Conclusions Information from manufacturers can be used to identify frequently used and category-specific flavourings. Qualitative and quantitative ingredient information can be used to successfully predict an e-liquid's flavour category, serving as an example for regulators that have similar datasets available.

The p53/p21/p16 and PI3K/Akt signaling pathways are involved in the ameliorative effects of maltol on D‐galactose‐induced liver and kidney aging and injury

“…C.A Meyer) and other Traditional Chinese Medicines (Figure 1a). To date, as an approved food additive in many countries, maltol has been widely used in food, personal care products, and tobacco products for enhancing flavor to reduce the amount of sugar needed (Krusemann et al, 2020). The effect of maltol on slowing down biological aging and injury in models has recently drawn considerable attention, and it has been confirmed that maltol can diminish behavioral dysfunction and neurological deficits, and slow age‐associated brain aging in one of our previous work (Sha et al, 2019).…”

An Observational Study of Vaping Knowledge and Perceptions in a Sample of U.S. Adults

“…Vape products come in a variety of styles, and there are over 7,000 available flavors in the market [ 9 - 11 ]. A cross-sectional survey in a large cohort (N = 728) was carried out to examine the relationship between product characteristics and e-cigarette appeal [ 12 ].…”

Flavor-Toxicant Correlation in E-cigarettes: A Meta-Analysis

“…This observation is in agreement with the results of a recent report that analyzed the flavor ingredients in ECIG liquids marketed in The Netherlands using information provided by the manufacturers. 36 …”