Journal Article

A Device-Independent Evaluation of Carbonyl Emissions from Heated Electronic Cigarette Solvents

Shusterman, Dennis, Chen, Wenhao, Matsuo, Toshiki, Ito, Kazuhide, Fowles, Jeff, Kumagai, Kazukiyo, Mendell, Mark, Liao, Jiawen, Wang, Ping

2017

Overview

To investigate how the two main electronic (e-) cigarette solvents-propylene glycol (PG) and glycerol (GL)-modulate the formation of toxic volatile carbonyl compounds under precisely controlled temperatures in the absence of nicotine and flavor additives. PG, GL, PG:GL = 1:1 (wt/wt) mixture, and two commercial e-cigarette liquids were vaporized in a stainless steel, tubular reactor in flowing air ranging up to 318°C to simulate e-cigarette vaping. Aerosols were collected and analyzed to quantify the amount of volatile carbonyls produced with each of the five e-liquids. Significant amounts of formaldehyde and acetaldehyde were detected at reactor temperatures ≥215°C for both PG and GL. Acrolein was observed only in e-liquids containing GL when reactor temperatures exceeded 270°C. At 318°C, 2.03±0.80 μg of formaldehyde, 2.35±0.87 μg of acetaldehyde, and a trace amount of acetone were generated per milligram of PG; at the same temperature, 21.1±3.80 μg of formaldehyde, 2.40±0.99 μg of acetaldehyde, and 0.80±0.50 μg of acrolein were detected per milligram of GL. We developed a device-independent test method to investigate carbonyl emissions from different e-cigarette liquids under precisely controlled temperatures. PG and GL were identified to be the main sources of toxic carbonyl compounds from e-cigarette use. GL produced much more formaldehyde than PG. Besides formaldehyde and acetaldehyde, measurable amounts of acrolein were also detected at ≥270°C but only when GL was present in the e-liquid. At 215°C, the estimated daily exposure to formaldehyde from e-cigarettes, exceeded United States Environmental Protection Agency (USEPA) and California Office of Environmental Health Hazard Assessment (OEHHA) acceptable limits, which emphasized the need to further examine the potential cancer and non-cancer health risks associated with e-cigarette use.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Acetaldehyde / Acetaldehyde - analysis / Acetone / Acrolein / Acrolein - analysis / Additives / Air Pollution - analysis / Biology and Life Sciences / Breakdowns / Cancer / Carbonyl compounds / Carbonyls / Cigarette smoking / Cigarettes / Electronic cigarettes / Electronic Nicotine Delivery Systems - adverse effects / Emissions / Engineering schools / Environmental assessment / Environmental hazards / Environmental health / Environmental protection / Flavor / Flavors / Formaldehyde / Formaldehyde - analysis / Glycerol / Glycerol - chemistry / Hazard assessment / Health hazards / Health risks / Indoor air quality / Interdisciplinary aspects / Laboratories / Liquids / Medicine and Health Sciences / Molecular weight / Nicotine / Physical Sciences / Propylene / Propylene glycol / Propylene Glycol - chemistry / Public health / Reactors / Smoking / Smoking cessation / Social Sciences / Solvents / Stainless steel / Temperature / Test procedures / Tobacco / Topography