Supplement Project: Role of Sweet Flavors in E-Cigarettes

The purpose of this study is to investigate how flavor produced by the components of e-cigarette liquids contribute to a users’ perception of sweetness and what impact flavor has on users’ perception of attractiveness.


Initial data indicate that e-cigarette flavors perceived as sweet are appealing to young adults and smokers trying to quit combustible cigarette smoking; however, little is known about how sweet e-cigarette flavors influence initiation, maintenance, and smoking cessation. There are also little data on the identity and amounts of the chemicals users inhale when using an e-cigarette flavor perceived as sweet. In this supplement to an ongoing study, investigators will measure and examine the subjective responses (using sensory and hedonic scales) to six flavors of a popular commercial e-cigarette from 80 established e-cigarette users (ages 18-21 and older in two age groups); participants will include both former and current combustible cigarette smokers. Investigators will then use standard liquid chromatography techniques and two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS) analysis to analyze the e-cigarette liquids so as to identify and quantify the chemicals most likely associated with perceptions of sweetness; and will evaluate these compounds for toxicity. Finally, to determine how sweet flavors may be used to mask the bitterness of nicotine, investigators will quantify the sweet-associated chemicals across varying nicotine strengths to determine how levels of these compounds may change with changing nicotine level. Study results may inform regulatory activities related to e-cigarettes and flavors.