The effects of alcohol-containing e-cigarettes on young adult smokers

Abstract

Background: The liquids (e-liquids) used in an electronic cigarette (e-cigarette) contain myriad chemicals without adequate human inhalation safety data. Furthermore, the absence of e-liquid labeling requirements poses a formidable challenge to understanding how e-liquid constituents may promote nicotine addiction and/or have independent or synergistic biological effects when combined with nicotine. Ethyl alcohol is such a constituent, but has received little scientific interest in this context.

Methods: Using a randomized, double blind, crossover design, acute changes in subjective drug effects, motor performance and biochemical measures of alcohol and nicotine intake were evaluated after directed and ad lib puffing from two commercially available e-liquids containing nicotine (8 mg/ml), vanilla flavor and either 23.5% (high) or 0.4% (trace) alcohol.

Results: While no differences in subjective drug effects were observed between alcohol conditions, performance on the Purdue Pegboard Dexterity Test (PPDT) improved under the trace, but not under the 23.5% alcohol condition. Although plasma alcohol levels remained undetectable during testing, urine ethyl glucuronide (EtG), an alcohol metabolite, became measurable in three participants after puffing from the 23.5% alcohol e-cigarette.

Conclusions: Brief use of a widely available type of e-cigarette containing an e-liquid purchased from an internet vendor can negatively impact psychomotor performance and in some instances, produce detectable levels of a urine alcohol metabolite. Given the widespread and unregulated use of e-cigarettes, especially by youth and other vulnerable populations, further studies are needed to evaluate both the acute safety and long-term health risks of using alcohol-containing e-cigarettes.

Keywords: Alcohol; Alcohol inhalation; Nicotine; Vaping; e-Cigarettes; e-Liquid.

Fig. 1

The subjective ratings of stimulant effects and sedating effects of the BAES under high (23.5%) and trace (0.4%) alcohol e-liquid conditions. Assessments were obtained at baseline, after directed puffing and at the end of the first ad lib session. No significant treatment differences were observed (p>0.05). Error bars = SEM

Fig. 2

Change in composite Purdue Pegboard Dexterity Test (PPDT) performance scores under high and trace alcohol conditions. Assessments were obtained at baseline, after directed puffing and at the end of the first ad lib session. With repeated administration, PPDT performance improved (more pins completed in allotted time) in the trace alcohol condition, but not under the high alcohol condition. Error bars = SEM.