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  1. Tobacco Science & Research

Yale TCORS: Irritant Flavor Products in Heated E-Cigarette Liquids and Vapors

Principal Investigator: Suchitra Krishnan-Sarin and Stephanie O'Malley

Funding Mechanism: National Institutes of Health - Grant

ID number:  3 P50 DA036151-03S1

Award Date: 8/28/2015

Institution: Yale University


While many of the flavorings used in e-cigarette liquids are generally recognized as safe in food, the safety of inhaling flavorings when using e-cigarettes has not been established. Popular e-liquid flavor mixes contain aldehydes such as cinnamaldehyde (cinnamon), carvone (spearmint), and terpenoids such as menthol (mint) and limonene (citrus). Notably, aldehydes and other chemicals are known to activate the transient receptor potential (TRP) ion channels in respiratory cells, thereby causing irritation in the respiratory system. The goal of the project is to study the impact of flavor chemicals on the TRP ion channels. Specific aims are: (1) to identify the chemical reaction products of e-liquid flavorings produced during heating and aerosolization; (2) to compare responses of TRP ion channels to e-liquids and their aerosols; and (3) to examine the sensitivity of newly-identified chemosensory receptors to flavorings and their products. To investigate these aims, researchers will use a variety of analytical techniques, including high performance liquid chromatography-mass spectrometry (HPLC-MS), gas chromatography-mass spectrometry (GC-MS), gas chromatography-flame ionization detector (GC-FID), and other screening approaches. The study will provide new data that may inform regulatory activities related to toxic and potentially toxic constituents in e-cigarette liquids.