A new way to identify chemical compounds in e-cigarettes

Mar. 3, 2020
Cover of Analytical Methods

Ilias KavourasTo date, there have been nearly 3,000 hospitalizations and 68 deaths due to electronic cigarette or vaping product use-associated lung injury in the United States. Data from the CDC show that vitamin E acetate, an unregulated additive in some THC-containing vaping products, is strongly linked to this outbreak.

Electronic cigarettes heat a solution of nicotine to generate nicotine vapors. The solution (e-liquid or vape juice) contains the solvents propylene glycol and glycerol and many other compounds as flavorings and preservatives. Manufacturers are not required to disclose the names or levels of these compounds in their products or their potential health impact on humans. Since there is a great range of what these chemicals could be, it is challenging and costly to identify them consistently.

In a study featured on the cover of Analytical Methods, CUNY SPH Professor Ilias Kavouras and team came up with a method to quickly and accurately determine the content and functional characteristics of the compounds used as flavorings and preservatives in vape juices.

Kavouras and his team used nuclear magnetic resonance (NMR) spectroscopy, a nondestructive method that requires minimal sample preparation, to analyze the e-liquid and the resultant e-vapors holistically. This method provides unique, robust, and reproducible qualitative and quantitative information on all chemical species in the sample.

“While more advanced steps can be taken to uniquely determine the chemical structure of these compounds, our method affords a precise and accurate approach to screen what is in the vape juices, compare and group them,” says Kavouras. “This is useful as there are more than 5,000 flavors currently on the market, up 50 percent from a few years ago. Our method allows for the rapid characterization of them.”

The study can be used to inform toxicological and risk assessment investigations leading to a better understanding of the risks of e-cigarettes.

Oluwabunmi M. Dada, Marie-Cecile G. Chalbot and Ilias G. Kavouras. “Functional characterization of flavorings in electronic cigarette refill liquids by nuclear magnetic resonance spectroscopy,” Analytical Methods, 2020, 12, 611.