Electron Microscopic Analysis of Silicate and Calcium Particles in Cigarette Smoke Tar

Scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM-EDS) supplies information that is complementary to those data traditionally obtained using inductively coupled plasma-mass spectrometry for analysis of inorganic tobacco and tobacco smoke constituents. The SEM-EDS approach was used to identify select inorganic constituents of mainstream cigarette smoke "tar." The nature of SEM-EDS instrumentation makes it an ideal choice for microstructural analyses as it provides information relevant to inorganic constituents that could result from exposure to combusted tobacco products. Our analyses show that aluminum silicates, silica, and calcium compounds were common constituents of cigarette mainstream smoke "tar." Identifying inorganic tobacco smoke constituents is important because inhalation of fine inorganic particles could lead to inflammatory responses in the lung and systemic inflammatory responses. As cigarette smoking causes chronic inflammation in the respiratory tract, information on inorganic particulate in mainstream smoke informs efforts to determine causative agents associated with increased morbidity and mortality from tobacco use.