Determination of Selected Chemical Levels in Room Air and on Surfaces after the Use of Cartridge- and Tank-Based E-Vapor Products or Conventional Cigarettes

Abstract

There is an ongoing debate regarding the potential of secondhand exposure of non-users to various chemicals from use of e-vapor products (EVPs). Room air levels of 34 chemicals (nicotine, propylene glycol (PG), glycerol, 15 carbonyl chemicals, 12 volatile organic chemicals (VOCs), and four selected trace elements) were measured where EVPs and cigarettes were used by n = 37 healthy adult tobacco users in an exposure chamber. The products used were MarkTen^® 2.5% Classic (Group I), a Prototype GreenSmoke^® 2.4% (Group II), Ego-T^® Tank with subjects' own e-liquids (Group III) and subjects' own conventional cigarettes (Group IV). Products were used under controlled conditions and 4-h ad libitum use. Background (without subjects) and baseline levels (with subjects) were measured. Cumulative 4-h. levels of nicotine, PG and glycerol measured were several-fold below the time-weighted average limits used in workplace exposure evaluation. Most the other chemicals (>75%) were at or below the limit of quantification during EVP use. Significant levels of chemicals (17 out of 34) were observed in Group IV. Overall, our results indicate that under the study conditions with the products tested, cumulative room air levels of the selected chemicals measured over 4-h were relatively small and were several-fold below the current occupational regulatory and consensus limits.

Keywords: conventional cigarettes; electronic cigarettes; electronic vapor products; glycerol; nicotine; passive vaping; propylene glycol; room air chemicals; secondhand smoke; thirdhand exposure.

Figure 1

Overall Study Conduct and Sampling Schedule.

Figure 2

Schematic of the exposure chamber with air sampling points. HVAC: Heating, Ventilating, and Air Conditioning.

Figure 3

Mean levels of nicotine (A); propylene glycol (B); glycerol (C) and formaldehyde (D) in RAS at baseline and from the use of the two EVPs (Groups I and II) and the tank product (Group III) over four hours of use. The dashed lines represent limits for air contaminants set by various agencies (value shown as 8-h time weighted average permissible exposure limit); nicotine: Occupational Safety and Health Administration (OSHA) limit of 500 μg/m³; PG: American Industrial Hygiene Association (AIHA) limit of 10,000 μg/m³ (wide dashed lines) and Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (OEHHA) limit of 7000 μg/m³ (narrow dashed lines); glycerol: OSHA limit of 10,000 μg/m³; and formaldehyde: OSHA limit of 980 μg/m³ (wide dashed lines) and OEHHA limit of 9 μg/m³ (narrow dashed lines).

Figure 3

Mean levels of nicotine (A); propylene glycol (B); glycerol (C) and formaldehyde (D) in RAS at baseline and from the use of the two EVPs (Groups I and II) and the tank product (Group III) over four hours of use. The dashed lines represent limits for air contaminants set by various agencies (value shown as 8-h time weighted average permissible exposure limit); nicotine: Occupational Safety and Health Administration (OSHA) limit of 500 μg/m³; PG: American Industrial Hygiene Association (AIHA) limit of 10,000 μg/m³ (wide dashed lines) and Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (OEHHA) limit of 7000 μg/m³ (narrow dashed lines); glycerol: OSHA limit of 10,000 μg/m³; and formaldehyde: OSHA limit of 980 μg/m³ (wide dashed lines) and OEHHA limit of 9 μg/m³ (narrow dashed lines).