UCLA

Introduction: Vape shops have grown in popularity among adults and youth. The increased popularity of electronic cigarettes has triggered many new businesses to open within the last three years to sell electronic cigarettes devices, flavor liquids and provide a place for lounging. High levels of ultrafine particles (UFP) are generated when active vaping is occurring.

Objectives: 1. Quantify and understand the spatial distribution of ultrafine particles in vape shops. 2. Identify factors that generate elevated levels of ultrafine particle concentrations.

Methods: Two vape shops in Southern California were recruited to participate in the study. There were six testing days for vape shop A and four testing days for vape shop B. Ultrafine particles were collected using two TSI Condensation Particle Counters. Carbon dioxide, relative humidity and temperature were also measured using a TSI Q-Trak Plus. CPC A was placed in a high activity area and was kept there for subsequent sessions. CPC B rotated around the store and outside. The Q-Trak was placed with CPC A during the sampling sessions. The air exchange rate (AER) was calculated using one overnight CO2 trend data using the TSI Q-trak.

Results: A temporal profile of UFP showed that high spikes of UFP were observed during vaping. The CPC placed in a low activity area, showed similar up and down fluctuations of UFP as shown in CPC A, even when no activity was occurring near the instrument. The UFP increased significantly when 1-2 and 3+ individuals were vaping compared to when no vaping was occurring. The UFP differed significantly (P<0.001) in both vape shops even when averaging the UFP concentration when zero, 1-2 and 3+ people were smoking. This is likely due to differences in the ventilation of the shops. The AER for Vape Shop A was 3.8hour-1 and for Vape Shop B is 4.8hour-1. The indoor-outdoor ratio is 10:1 and 1.4:1 for Vape Shop A and Vape Shop B respectively. The data also showed when CO2 levels are increased the UFP levels also increased.

Conclusions: This research shows that e-cigarettes are a major source of UFP in the vape shops. Also, higher levels of UFP is seen when 1-2 and 3+ individuals are smoking and the indoor UFP levels are significantly reduced in the more ventilated shop.