Aerosol particle effective density of heated tobacco products measured with a tandem mass and mobility analyzer

Abstract

To better understand the properties of “heat-not-burn” (HNB) tobacco products, the particle effective densities of aerosols emitted from 10 brands of HNB cigarettes are measured with a tandem mass and mobility analyzer, composed of a centrifugal particle mass analyzer (CPMA) and a scanning mobility particle sizer (SMPS). The aerosols are generated with a smoking machine and aged in a Teflon bag for 1 h prior to the measurement. The results show that the aerosol effective densities are independent of the particles’ mass, with their average values in the range of 1097–1443 kg/m³, which aligns with the spherical morphology identified by scanning electron microscope (SEM). However, the tobacco heating mode has a significant effect on the particle effective density, and the average values from the peripheral, needle and blade heating modes are measured at 1373, 1253 and 1183 kg/m³, respectively. The geometry of tobacco sticks such as their lengths and circumferences also has an impact on the particle effective density. Specifically, longer cigarette lengths and slimmer sticks produce particles with higher effective densities (∼5 %–20 % higher). Although previous studies have shown that the HNB cigarettes generate less harmful toxicants than the traditional combustion cigarettes, this work demonstrates no significant difference in their aerosol particle effective densities.