Online characterization of particle size distribution and molecular structure of cigarette smoke aerosols and their...

Exposure of cigarette smoke aerosols poses a serious health risk to humans, with particle size, concentration and chemical composition being important influencing factors. In this study physical and chemical properties of cigarette smoke aerosols were analyzed online to assess their exposure risk. Utilizing a fast-response particle analyzer, cigarette smoke particles were characterized for their small size (< 600 nm) and high concentration (10⁹ particles cm^-3). Multiple-path particle dosimetry model simulations showed that particles are deposited in the human respiratory system at a number dose of 10¹⁰ particles puff^-1, with the highest deposited dose in the pulmonary region. The deposition of ultrafine particles was also emphasized with up to 10⁹ particles puff^-1. A home-made photoionization aerosol mass spectrometer combined with Hefei synchrotron radiation was used to probe the molecular structure of particulate components for cigarette smoke. For the first time, isomers in cigarette smoke particulate matter were distinguished. The identified toxic or carcinogenic substances cover a wide volatility and reactivity space, including carbonyl compounds, alkaloids, polycyclic aromatic hydrocarbons, and unsaturated organic acids etc. The potential effects of components with high volatility and activity on the human respiratory system in the form of particles provide new insight into cigarette smoke exposure.