Effects of E-cigarette Flavors on Youth TCORS 2.0

This study is an examination of the influence of sweet and cooling flavors on the appeal and abuse potential of nicotine-containing e-cigarettes among susceptible youth.

Researchers will examine the influence of sweet and cooling flavors on the appeal and abuse potential of nicotine-containing e-cigarettes among susceptible youth. Participants will rate the flavor intensity, coolness, sweetness, and irritation experienced using validated rating scales. Forty youth (18-20 years of age) who have experience with e-cigarettes and will participate in 1 laboratory session. They will receive 1 nicotine concentrations (36mg/ml nicotine salt) during the session; during the session they will be exposed, in random order, to sweet (watermelon) and sweet-cooling (watermelon-menthol) flavors combined with the assigned session nicotine concentration.

Flavor and nicotine concentration is blinded to participant. Research staff and investigators are blinded to flavor order administer to participants.

The Labeled Hedonic Scale will be used to ask about liking and wanting of the e-cigarette (one item Visual Analog Scale with ratings ranging from "most disliked sensation imaginable" to "most liked sensation imaginable" with higher values indicating greater liking).

Following administration of e-cigarette condition 1 (+10 minutes), following administration of e-cigarette condition 2 (+40)

Difference between e-cigarette effects for each e-cigarette condition as measured by the computerized version of the Drug Effects Questionnaire (DEQ). Participants will self-report their responses using a computer mouse to indicate where on the scale response falls. A modified version of the Drug Effects Questionnaire (DEQ) will be used in which participants rate acute responses to the e-cigarette on a 0-100mm scale from "not at all" (0mm) to "extremely" (100mm).

Following administration of e-cigarette condition 1 (+10 minutes), following administration of e-cigarette condition 2 (+40)

Difference from baseline in craving for each e-cigarette condition will be measured by the Generalized Labeled Magnitude Scale (gLMS). Participants will self-report their craving for e-cigarettes using a computer mouse to indicate where on the scale response falls. The Generalized Labeled Magnitude Scales (gLMS) are category ratio scales with seven semantic labels: "no sensation", "barely detectable", "weak", "moderate", "strong", "very strong", and "strongest imaginable", positioned quasi-logarithmically as per empirically determined semantic magnitudes on a 0-100 scale (strongest imaginable at the 100 end).

At baseline (+0 minutes), Following administration of e-cigarette condition 1 (+10 minutes), following administration of e-cigarette condition 2 (+40)

Difference in irritation at each e-cigarette condition as measured by the computerized Generalized Labeled Magnitude Scale (gLMS). Participants will self-report their responses using a computer mouse to indicate where on the scale response falls. The Generalized Labeled Magnitude Scales (gLMS) are category ratio scales with seven semantic labels: "no sensation", "barely detectable", "weak", "moderate", "strong", "very strong", and "strongest imaginable", positioned quasi-logarithmically as per empirically determined semantic magnitudes on a 0-100 scale (strongest imaginable at the 100 end).

Following administration of e-cigarette condition 1 (+10 minutes), following administration of e-cigarette condition 2 (+40)

Inclusion Criteria: Ages 18-20 years Able to read and write Used e-cigs at least 10 times in lifetime Used e-cigs in past 30 days Exclusion Criteria: Current use of non-prescription substances besides nicotine, marijuana, alcohol Any significant current medical or psychiatric condition Known hypersensitivity to propylene glycol Pregnant or lactating females Uncontrolled asthma Nut/e-liquid flavorant allergy current marijuana (tetrahydrocannabinol) vaping + E-cigarette or vaping use Associated Lung Injury (EVALI) symptoms

Lim J, Wood A, Green BG. Derivation and evaluation of a labeled hedonic scale. Chem Senses. 2009 Nov;34(9):739-51. doi: 10.1093/chemse/bjp054.