EC aerosol was characterized from a single coil atomizer powered by avariable voltage EC battery at the minimum and maximum dial settings (3.3, 11.2 Watts, W), and a lab controlled power supply (3–11.9 W). Aerosol particle size distribution was measured by a Scanning Mobility Particle Sizer and Aerodynamic Particle Sizer, spanning 16 nm to19.8 μm. A mouth puff was simulated using a100 mL glass syringe. Consistent with prior studies, sub-micron EC aerosol size distributions were bimodal, with peaks at 40 and 200 nm, however apreviously unreported third mode was observed at approximately 1000 nm. The ~1000 nm mode accounted for 7-20x the aerosol mass of the smaller modes. Increasing atomizer power decreased count concentration of particles <600 nm but increased particle count >600 nm. Particle mass distribution shifted toward micron sized particles with increasing power and increased the respirable fraction ofaerosol, likely due to increased coagulation and condensation around nano-sized particles. Vaping power greatly affects EC aerosol count and mass distribution.Mouth puffed EC aerosol spans amuch wider particle size range than previously reported, although the major portion ofthe mass is still well within the alveolar size range the larger particles will deposit within the oro-pharyngealcavity at 2-3x greater efficiency than inalveoli. These observations have major clinical implications, as aerosol particle size distribution determines deposition sites along the respiratory tract. The results of this experiment stress the need for further research toinform the design, regulation and use of e-cigarette products.
Citation
Floyd, Evan L., Lurdes Queimado, Jun Wang, James L. Regens, and David L. Johnson. “Electronic Cigarette Power Affects Count Concentration and Particle Size Distribution of Vaping Aerosol.” Edited by Ana María Rule. PLOS ONE 13, no. 12 (December 31, 2018): e0210147. https://doi.org/10.1371/journal.pone.0210147.
Floyd, Evan L., Lurdes Queimado, Jun Wang, James L. Regens, and David L. Johnson. “Electronic Cigarette Power Affects Count Concentration and Particle Size Distribution of Vaping Aerosol.” Edited by Ana María Rule. PLOS ONE 13, no. 12 (December 31, 2018): e0210147. https://doi.org/10.1371/journal.pone.0210147.
