Prediction of Particle Deposition in Human Respiratory System

Airborne particulate matter has caused growing public concerns with regard to their effect on human health. Knowledge of particle dosage in human bodies is of importance for risk evaluation from exposure to high concentration aerosols. The present study utilizes mathematical models to predict particle deposition in a representative human respiratory system. An anatomical model of the human respiratory system is obtained from available physiological data and morphometric measurements from the literature. The transport models employed include diffusion, gravitational settling, inertial impaction and interception. Deposition calculation has been performed for particle sizes between 0.001 and l0 pm aerodynamic diameter to study the effects of airway regions, exercise levels, functional reserve capacities and genders. The predicted deposition patterns compare satisfactorily well with those from published literature. The effect of different exercise levels, which account for different tidal volumes and breathing rates, exhibits clear differences in deposition while variation in other parameters considered has only a small effect on deposition. For a given breathing condition, submicron particles appear to deposit more and deeper into the airways than super-micron particles