AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Quantitative Assessment of Organic Compound Deposition in the Human Respiratory System from Rechargeable E-Cigarettes
YUAN SHAO, Kirsten Koehler, Ana Rule, Wentai Luo, Kevin McWhirter, Jim Pankow, Johns Hopkins Bloomberg School of Public Health
Abstract Number: 585 Working Group: Health-Related Aerosols
Abstract To better understand exposure to inhalation hazards from e-cigarette aerosols, it is important to characterize the particle size-specific deposition in human airways. A foam sampler has been developed to capture the fraction of aerosols that deposits in the human respiratory system as a function of particle size. The objective of this study was to simulate e-cigarette vaping, and to quantify the fraction of organic compounds deposited in the human respiratory tract. We evaluated aerosols generated by JUUL devices (Virginia Tobacco flavor) using foam lung deposition samplers (LDS). An automated e-cigarette aerosol sampling system was designed for this study. E-cigarette emissions were generated at a flow rate of 4 LPM for 3 seconds with a 30-second break between puffs. The emissions were pulled through the LDS and the fraction of aerosol not collected in the LDS was collected with a 25mm Teflon filter to represent the exhaled fraction. JUUL samples were collected with 0, 20, 40 and 60 puffs per sample, each with 5 replicates. Total concentrations of Propylene Glycol (PG), Nicotine, and Glycerin (GL) in the LDS and filters were analyzed using GC-MS. The median mass collected in the LDS was 168.8 ug/puff for PG; 31.3 ug/puff for Nicotine, and 353.2 ug/puff for GL. The resulting median percentage of mass depositing in the lungs was 60% for PG; 60% for Nicotine, and 44% for GL. E-cigarettes are a source of hazardous organic compounds. We found that about half of the total inhaled mass was collected in the lung deposition sampler, indicating that compounds reach and nearly 50% deposit in the human respiratory tract during e-cigarette use. Additional studies are needed to evaluate the deposited mass for other popular e-cigarette devices and flavors.