Quantitative Estimation of Micro-sized Particle Deposition in Tracheobronchial Airways

Abstract Introduction Assessment and prediction of health risks caused by exposure to dust particles in ambient air is a relevant task the contemporary healthcare has to tackle. To do it, it is necessary to develop mathematical models that make it possible to estimate introduction of dust particles into the human body. Purpose The present study focuses on quantification of particles that are deposited in the tracheobronchial (TB) airways (G0–G5) as well as particles able to reach the lungs. We investigate deposition of particles with various sizes and density that are present in ambient air in a large industrial center. Methods Inhaled air is considered a multiphase mixture of a homogenous gas and solid dust particles. We considered non-stationary airflow during light, moderate and vigorous activity. Results We quantified a share of deposited particles (SDP) with various dispersed structure (between 0.5 and 20 µm) and density (1000, 2000, 2700, 4000 kg m –3 ) in the TB airways; the article provides computed motion paths of particulate matter. Conclusions Particle density mostly influences differences in deposition of micro-sized particles (2.5–20 µm). Deposition of small particles (PM1) slightly depends on particle density and intensity of breathing. Larger particles (2.5–20 µm) are governed primarily by inertial impaction and gravitational settling. As particle sizes and mass go down, SDP in the airways decreases and accordingly there is a growth in the share of particles able to penetrate small airways and reach the lungs. As the micro-sized particles (2.5–20 µm) density increases, the SDP increases, which is typical for all breathing modes. As respiratory intensity increases, SDP grows. Graphical abstract