Analysis of the composition of e-cigarette liquids using Gas Chromatography-mass spectrometry (2016)

Undergraduate: Justin Lackey

Faculty Advisor: Gary Glish
Department: Biology

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Electronic cigarettes (e-cigarettes) are an increasingly popular mode of nicotine delivery, available in many flavors from tobacco and menthol to numerous varieties of food and candy flavors. E-cigarettes are often thought to be safer than conventional tobacco products. However, the composition of e-cigarette liquids is not commonly disclosed by manufacturers and is essentially unregulated. These liquids typically consist of a humectant such as propylene glycol for consistency, a variety of flavorings, and nicotine. To volatilize nicotine and flavoring compounds the liquid is heated in an e-cigarette and the resulting vapor is inhaled. The first step in understanding the chemistry of e-cigarette vapor is determining the composition of the liquids. A selection of e-cigarette liquids was purchased from a local e-cigarette liquid manufacturer and distributor (The Vapor Girl, Chapel Hill NC) as well as samples taken from large distributors around the country. E-cigarette liquids were analyzed by gas chromatography-mass spectrometry, using a library search to identify the compounds detected. GC-MS was used to determine the constituent flavoring compounds used. Additionally, methods were developed to quantify and identify certain compounds found to be potentially of danger to health and that were particularly difficult to detect. Finally, the base of the locally purchased e-liquids was analyzed in order to determine the matrix in which the e-liquids were formulated.