Comparison of select analytes in aerosol from e-cigarettes with smoke from conventional cigarettes and with ambient air

Abstract

Leading commercial electronic cigarettes were tested to determine bulk composition. The e-cigarettes and conventional cigarettes were evaluated using machine-puffing to compare nicotine delivery and relative yields of chemical constituents. The e-liquids tested were found to contain humectants, glycerin and/or propylene glycol, (⩾75% content); water (<20%); nicotine (approximately 2%); and flavor (<10%). The aerosol collected mass (ACM) of the e-cigarette samples was similar in composition to the e-liquids. Aerosol nicotine for the e-cigarette samples was 85% lower than nicotine yield for the conventional cigarettes. Analysis of the smoke from conventional cigarettes showed that the mainstream cigarette smoke delivered approximately 1500times more harmful and potentially harmful constituents (HPHCs) tested when compared to e-cigarette aerosol or to puffing room air. The deliveries of HPHCs tested for these e-cigarette products were similar to the study air blanks rather than to deliveries from conventional cigarettes; no significant contribution of cigarette smoke HPHCs from any of the compound classes tested was found for the e-cigarettes. Thus, the results of this study support previous researchers' discussion of e-cigarette products' potential for reduced exposure compared to cigarette smoke.

Comparing the cancer potencies of emissions from vapourised nicotine products including e-cigarettes with those of tobacco smoke

“…Biomarkers for the same compounds declined rapidly in smokers switching to ECs at rates similar to abstinence from smoking over 5 days 52. Neither compound is normally detectable in EC vapour yet both have been shown above to account collectively for more than three-quarters of the cancer potency of tobacco smoke 53. This close correlation between reduced emissions in EC vapours and their associated biomarkers for two of the most important carcinogens in tobacco smoke supports the use of emissions in estimating potency and risk.…”

Electronic cigarettes—A review of the physiological health effects

“…Sleiman et al (2016) identified two other potential carcinogens in EC vapour: propylene oxide and glycidol. Other articles showed similar results, with increasing levels of toxicants when higher-powered devices were used (Laugesen 2008;McAuley et al 2012;Goniewicz et al 2014b;Hutzler et al 2014;Kosmider et al 2014;Tayyarah and Long 2014;Geiss et al 2015;Herrington and Myers 2015; Zucchet and Schmaltz 'Connell et al 2015;El-Hellani et al 2016;Jo and Kim 2016;Leigh et al 2016;Sleiman et al 2016;Talih et al 2016). The amount and types of these degradation products vary substantially in different studies, making generalizations about the health effects of ECs difficult.…”

“…Other EC liquids contain toxicants not supposed to be found in such products (Goniewicz et al 2014a;Lisko et al 2015). Many studies have found that EC vapours contain TSNAs (Westenberger 2009;Kim and Shin 2013;Cheng 2014;Goniewicz et al 2014b;Tayyarah and Long 2014;Farsalinos et al 2015a;Flora et al 2016). For example, Kim and Shin (2013) found an average of 12.99 ± 18.23 μg/L of these toxicants in 105 EC liquids from Korean shops.…”

Measurement of an electronic cigarette aerosol size distribution during a puff

“…Knowledge of the particle size distribution and chemical composition is essential because it mainly determines deposition hotspots and the subsequent impact on human health. A chemical analysis of an e-cigarette smoke has been carried out in several studies [3,[6][7][8] and the results were compared with conventional cigarettes concerning the presence of carcinogens and other harmful constituents. The results showed that although the levels of harmful constituents varied considerably among different brands of e-cigarettes, they were around 1 to 2 orders lower than in conventional cigarette aerosol.…”