Identification of Cytotoxic Flavor Chemicals in Top-Selling Electronic Cigarette Refill Fluids

Introduction:
This text provides an in-depth analysis of the scientific report on the potential health risks associated with the use of electronic cigarettes (ECs) and their refill fluids. Readers will learn about the adverse health effects, cytotoxic flavors, and flavor chemicals found in EC refill fluids, as well as the implications for product regulation and consumer safety.

Key Points:

* The study identifies and quantifies flavor chemicals in 20 popular refill fluids, establishing which are cytotoxic and identifying their flavor chemical ingredients.
* EC users (N = 789) indicated their flavor preferences from 18 possible flavor categories, with the top six being "Berries/Fruits/Citrus," "Sweet," "Bakery/Dessert," "Mint/Menthol," "Candy," and "Buttery/Cream/Caramel/Vanilla."
* a total of 99 flavor chemicals were identified and quantified in the 20 EC refill fluids purchased in local shops, with concentrations ranging from 0.63 mg/ml to 27.9 mg/ml.
* The y-axis of the heat map ranks chemicals by their safety classification, with most flavor chemicals being esters, terpenes, phenols, alcohols, ketones, or aldehydes.
* The cytotoxicities of the 20 popular refill fluids were evaluated using the MTT assay, with some products reaching at least an IC70 (30% inhibition vs control) or IC50 (50% inhibition vs. control), indicating cytotoxicity.
* Cytotoxicity was found to be positively correlated with the total number and total concentration of flavor chemicals in each product.
* The majority of flavor chemicals were esters, consistent with fruity flavors being the most popular.
* The study identified a small subset of available flavor chemicals used in EC refill fluids, which should help focus future research in this area.

Main Message:
The scientific report highlights the potential health risks associated with the use of electronic cigarettes and their refill fluids. With a wide variety of cytotoxic flavors and flavor chemicals found in EC refill fluids, it is crucial to establish concentration limits and labeling requirements for these substances. The findings emphasize the need for further research and regulation to ensure consumer safety and protect public health.

hua, My, Esther E. Omaiye, Wentai Luo, Kevin J. McWhirter, James F. Pankow, and Prue Talbot. “Identification of Cytotoxic Flavor Chemicals in Top-Selling Electronic Cigarette Refill Fluids.” Scientific Reports 9, no. 1 (February 26, 2019): 2782. https://doi.org/10.1038/s41598-019-38978-w.