Effects of sweet flavorings and nicotine on the appeal and sensory properties of e-cigarettes among young adult vapers: Application of a novel methodology

Abstract

Introduction Product characteristics that impact e-cigarette appeal by altering the sensory experience of vaping need to be identified to formulate evidence-based regulatory policies. While products that contain sweet flavorings and produce a “throat hit” (i.e., desirable airway irritation putatively caused by nicotine) are anecdotally cited as desirable reasons for vaping among young adults, experimental evidence of their impact on user appeal is lacking. This experiment applied a novel laboratory protocol to assess whether: (1) sweet flavorings and nicotine affect e-cigarette appeal; (2) sweet flavorings increase perceived sweetness; (3) nicotine increases throat hit; and (4) perceived sweetness and throat hit are associated with appeal. Methods Young adult vapers (N=20; age 19–34) self-administered 20 standardized doses of aerosolized e-cigarette solutions varied according to a 3 flavor (sweet [e.g., cotton candy] vs. non-sweet [e.g., tobacco-flavored] vs. flavorless) × 2 nicotine (6 mg/mL nicotine vs. 0 mg/mL [placebo]) double-blind, cross-over design. Participants rated appeal (liking, willingness to use again and perceived monetary value), perceived sweetness and throat hit strength after each administration. Results Sweet-flavored (vs. non-sweet and flavorless) solutions produced greater appeal and perceived sweetness ratings. Nicotine produced greater throat hit ratings than placebo, but did not significantly increase appeal nor interact with flavor effects on appeal. Controlling for flavor and nicotine, perceived sweetness was positively associated with appeal ratings; throat hit was not positively associated with appeal. Conclusions Further identification of compounds in e-cigarette solutions that enhance sensory perceptions of sweetness, appeal, and utilization of e-cigarettes are warranted to inform evidence-based regulatory policies.

Effects of electronic cigarette liquid solvents propylene glycol and vegetable glycerin on user nicotine delivery, heart rate, subjective effects, and puff topography

“…In addition, surveys of ECIG users have demonstrated consistently that greater throat hit is associated with positive sensory effects such as overall device/liquid satisfaction and better taste (Etter, 2016;McQueen, Tower, & Sumner, 2011;Pokhrel, Herzog, Muranaka, & Fagan, 2015). However, in the present study higher ratings of "Throat Hit" did not coincide with more positive sensory effects and other experimental studies have demonstrated that throat hit is inversely associated with product satisfaction among young adult ECIG users (Goldenson et al, 2016). Because the 100PG:0VG liquid produced less positive sensory effects overall, the higher ratings of "Throat Hit" observed in this condition is likely another example of a negative sensory effect resulting from the use of this liquid.…”

Impact of e-liquid flavors on nicotine intake and pharmacology of e-cigarettes

“…Although average nicotine exposure between the usual and tobacco e-liquids were similar, the usual brand e-liquid was rated as more satisfying than the tobacco e-liquid, indicating that flavors play an important role in e-cigarette appeal. One study showed that while nicotine produces the throat-hit, it was the sweet flavors and not nicotine content that increased e-cigarette appeal (Goldenson et al, 2016). We did not see similar precise titration of nicotine exposure when we compared the strawberry flavor to the usual brand and tobacco e-liquids, respectively.…”

“…We did not see similar precise titration of nicotine exposure when we compared the strawberry flavor to the usual brand and tobacco e-liquids, respectively. The perceived better taste of the strawberry flavor likely made it more appealing than the tobacco flavor, and hence greater consumption and nicotine exposure (Goldenson et al, 2016). …”

Assessing electronic cigarette effects and regulatory impact: Challenges with user self-reported device power

“…In two of the studies, 121 young adult ECIG users (Study 1 n=101, Study 2 n=20; 57.5% current smokers) attended a single laboratory visit in which they self-administered experimenter-provided ECIGs (for details on the paradigm see Goldenson et al, 2016). In the other study, adult concurrent combustible cigarette and ECIG users (N=44) attended five visits in which they smoked their own preferred-brand cigarettes and used their own ECIGs.…”