A research team of the Quebec Heart and Lung Institute at the Université Laval designed a study to investigate the impact of a 1 hour acute vaping session on the pulmonary functions and respiratory mechanics. The originality of their study was to focus on healthy and asthmatic individuals and to use nicotine-free and flavour-free e-liquid.
No significant outcome after acute exposure to PG/VG e-vapor
The study was designed, in the absence of nicotine and flavor, to “create the best-case scenario where unwanted and possibly harmful contaminants are absent”. The pulmonary effects of PG and VG, which make up to 90% of the e-liquid, have been investigated on a panel constituted of asthmatic (10) and healthy volunteers (20).
The main finding of their trial is that acute exposure to e-cigarette vapors does not seem to cause significant functional pulmonary alterations in healthy and asthmatic individuals.
A few subjects however noticed symptoms when using the loaded e-cigarette. Cough, chest tightness, and secretions, were reported but no consensual differences in symptoms were noticed in healthy or asthmatic volunteers. The principal markers of a disorder like increased FeNO and serum CRP levels, were not observed in response to e-vapor exposure in the asthmatic group, no changes in lung functions were observed using either spirometry or forced oscillation technique.
An “urgent need to study the effects of chronic use”
The study doesn’t however report the type of e-cigarette used for this experiment. No indication either is given for the power used to vaporize the experimental e-liquid. The presence of acrolein and formaldehyde in e-vapor has been shown to originate from VG and PG, respectively, at high power. It was obviously not the case, here, but for the sake of experimental reproducibility, such information should be included.
The authors point out the urgent need to study the effects of chronic use, especially in more susceptible populations such as teenagers, smokers, and individuals with chronic lung diseases such as asthma and chronic obstructive pulmonary disease.
Boulay, M. È., Henry, C., Bossé, Y., Boulet, L. P., & Morissette, M. C. (2017). Acute effects of nicotine-free and flavour-free electronic cigarette use on lung functions in healthy and asthmatic individuals. Respiratory Research, 18(1), 33.
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