Water Content in E-Liquids

Study Overview
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Brief Summary
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This study looks at the effect of manipulating the water concentration of certain e-liquids on sensory perception.

Detailed Description
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This study looks at the effect of manipulating water concentration on e-cigarettes that contain aldehyde flavor chemicals on sensory perception. Regular e-cigarette users will be asked to complete 2 lab sessions in which they will sample 4 nicotine containing e-liquids. Each e-liquid will be sampled in four water concentration manipulations. Researchers will examine influence of flavor and water concentrations on sensory experience including appeal/liking and irritation and harshness.

Official Title
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Water Content In E-Liquids

Conditions
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Nicotine E-Cigarette Use

Intervention / Treatment
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* Other: Water Concentration 1
* Other: Water Concentration 2
* Other: Water Concentration 3
* Other: Water Concentration 4


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: at least 21 years old able to read/write >/= 6 mths e-cig use regular e-cig use (>/= 4 days/week) use of flavored e-cigs use of nicotine containing e-cigs urine cotinine >/= 200ng/ml no plan to quit e-cig use Exclusion Criteria: breastfeeding, pregnant, trying to become pregnant Medical conditions that increase risk of respiratory problems among participants Current use of illegal substances Medical conditions increasing risk of respiratory problems in nonpatient populations Current diagnosis of an untreated psychiatric condition Not fully vaccinated for Coronavirus-19

Ages Eligible for Study
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Minimum Age: 21 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Within subject design, all participants will receive all e-liquid flavors/water concentrations
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Experimental E-Liquid Order A<br>All participants will be given all e-liquids (i.e. all 16 flavor*water concentration combinations (4 flavors and four water concentrations)) in this within subject cross-over design study. Participants will be randomized in the order in which they receive the flavor conditions (across the 2 visits). For each flavor condition, water will be presented in the same order from hypothesized least irritating to most irritating. | Other: Water Concentration 1<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with no alteration to water concentration.<br>Other: Water Concentration 2<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 5% total water concentration of e-liquid.<br>Other: Water Concentration 3<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 10% total water concentration of e-liquid.<br>Other: Water Concentration 4<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 20% total water concentration of e-liquid.<br>|
| Experimental: Experimental E-Liquid Order B<br>All participants will be given all e-liquids (i.e. all 16 flavor*water concentration combinations (4 flavors and four water concentrations)) in this within subject cross-over design study. Participants will be randomized in the order in which they receive the flavor conditions (across the 2 visits). For each flavor condition, water will be presented in the same order from hypothesized least irritating to most irritating. | Other: Water Concentration 1<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with no alteration to water concentration.<br>Other: Water Concentration 2<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 5% total water concentration of e-liquid.<br>Other: Water Concentration 3<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 10% total water concentration of e-liquid.<br>Other: Water Concentration 4<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 20% total water concentration of e-liquid.<br>|
| Experimental: Experimental E-Liquid Order C<br>All participants will be given all e-liquids (i.e. all 16 flavor*water concentration combinations (4 flavors and four water concentrations)) in this within subject cross-over design study. Participants will be randomized in the order in which they receive the flavor conditions (across the 2 visits). For each flavor condition, water will be presented in the same order from hypothesized least irritating to most irritating. | Other: Water Concentration 1<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with no alteration to water concentration.<br>Other: Water Concentration 2<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 5% total water concentration of e-liquid.<br>Other: Water Concentration 3<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 10% total water concentration of e-liquid.<br>Other: Water Concentration 4<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 20% total water concentration of e-liquid.<br>|
| Experimental: Experimental E-Liquid Order D<br>All participants will be given all e-liquids (i.e. all 16 flavor*water concentration combinations (4 flavors and four water concentrations)) in this within subject cross-over design study. Participants will be randomized in the order in which they receive the flavor conditions (across the 2 visits). For each flavor condition, water will be presented in the same order from hypothesized least irritating to most irritating. | Other: Water Concentration 1<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with no alteration to water concentration.<br>Other: Water Concentration 2<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 5% total water concentration of e-liquid.<br>Other: Water Concentration 3<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 10% total water concentration of e-liquid.<br>Other: Water Concentration 4<br>* E-liquid containing 36mg/ml pronated nicotine will be administered with 20% total water concentration of e-liquid.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Irritation/Harshness | Change in irritation at each water level 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). | immediately after intervention, up to 15 minutes | 
| Appeal | Change in appeal at each water level as measured by the computerized Labeled Hedonic Scale (LHS). Participants will self-report their responses using a computer mouse to indicate where on the scale response falls. The Labeled Hedonic Scale (LHS) is a bipolar category ratio scale that ranges from -100 (most disliked) to 100 (most liked), with 'neither liked nor disliked' as midpoint. | immediately after intervention, up to 15 minutes | 
| Appeal | Change in appeal at each water level 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). | immediately after intervention, up to 15 minutes |