A Rapid and Sensitive Chemical Screening Method for E‑Cigarette Aerosols Based on Runtime Cavity Ringdown Spectroscopy

Growing demand of Juul and other electronic cigarettes, despite critical knowledge gaps about their chemical composition, has led to concerns regarding their potential health effects. We introduce a novel analytical approach, runtime cavity ringdown spectroscopy (rtCRDS) for rapid detection of oxidative products in e-cigarette aerosols, to facilitate the study of aerosol from a single puff of e-liquid. We report a systematic investigation of three flavors of commercial Juul pods (Virginia tobacco, mango, and menthol) and known commercial e-liquid ingredients (propylene glycol (PG), vegetable glycerin (VG), nicotine, ethyl maltol, benzoic acid, and nicotine benzoate) vaped using Juul devices. Juul e-liquids and neat chemical additives spiked into a 30:70 PG/VG solution were vaped and their aerosols were collected in 1-L Tedlar gas bags and analyzed using rtCRDS. Acetaldehyde, formaldehyde, and acetone were identified as primary oxidative products in aerosolized PG/VG. Ethanol was detected as a major constituent of the three commercial Juul flavors. Spectral intensities of carbonyl compounds increased with the addition of spikes, benzoic acid, ethyl maltol, and nicotine to PG/VG, suggesting that oxidative product generation increases with common additives. The method of direct, rapid analysis of e-cig aerosols introduced here can be used to complement traditional methods in vaping exposures.