ABSTRACT
Human lung deposition models are based typically on estimation of the physical behaviour of aerosol particles in a simplified anatomic model of the lung, that is as a series of branching cylinders with bifurcations of known angles allowing calculation of deposition by impaction, sedimentation and diffusion. Dose relates to the deposition, uptake and retention of each component of the ambient aerosol, which may be affected by a number of factors. The formation route of many aerosols from specific sources may determine the size range where particular components appear. The respiratory tract in the lung model is greatly simplified with division into four main regions: extrathoracic, bronchial, bronchiolar and alveolar-interstitial with simplifying assumptions for clearance broken down into simple considerations of mechanical clearance and translocation. Environmental and vehicle emissions data suggest that consideration of diesel particle dose on a number basis is valid, due to the size of particles observed and the efficiency of their penetration to the lung.
