Flavoring Chemicals and Aldehydes in E-Cigarette Emissions

• DOI: 10.1021/acs.est.7b02205
• Publication Date: 2017-08-17T20:40:06Z
• Authors: Skylar Klager; Jose Vallarino; Piers MacNaughton; David C. Christiani; Quan Lu; Joseph G. Allen
• Keywords: Flavoring Agents; Aldehydes; Nicotine; 13. Climate action; Formaldehyde; Electronic Nicotine Delivery Systems; Volatilization; 01 natural sciences; 3. Good health; 0105 earth and related environmental sciences

Regulations on e-cigarettes in the U.S. do not provide guidelines on the chemical content of e-cigarette liquids. We evaluated emissions of aldehydes and flavoring chemicals in e-cigarette vapor under typical usage conditions. We selected 24 e-cigarette flavors from the top selling disposable e-cigarette brands. E-cigarettes were connected to a pump drawing air for two second puffs with sixty-second intervals between puffs. The vapor was analyzed for the presence of aldehydes using high-performance liquid chromatography-ultraviolet detector and for the presence of flavoring chemicals with gas chromatography and an electron capture detector. All e-cigarette emissions tested contained at least one aldehyde and/or flavoring chemical on either the FEMA "High Priority Chemicals" or FDA Harmful and Potentially Harmful Constituents lists when sampled at typical usage conditions. Diacetyl, a known respiratory hazard, along with acetoin, were the most prevalent of the flavoring chemicals in e-cigarette vapor, being found in more than 60% of samples. The presence of propionaldehyde, acetaldehyde and formaldehyde were correlated, corroborating previous work suggesting thermal degradation as a pathway for aldehyde generation in e-cigarette vapors. Median formaldehyde concentrations of 626 μg/m3 in e-cigarette vapor exceed the ACGIH maximum concentrations allowable for workers of 370 μg/m3.