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iConcept Journal of Computational and Mathematical Biology
Title
iConcept Journal of Computational and Mathematical Biology
Editor
Maurice Ling
ISSN
2219-1402
Publisher
iConcept Press

iConcept Journal of Computational and Mathematical Biology

Deposition of Ultrafine Particles with Various Shapes in the Human Alveoli – A Model Approach

by Robert Sturm

Volume: 5 (2016); Issue: 4

Abstract

The present study deals with the theoretical modeling of ultrafine particle deposition in the alveoli of the human lungs. Respective deposition computations were conducted by assuming particle geometries ranging from ideal spheres to aggregates, which consisted of variable numbers of spherical components. For the simulation of pulmonary particle transport a stochastic lung structure characterized by high intra-subject variability of the airway morphometry was used. Besides total alveolar deposition also alveolar deposition in airway generations 12-25 was computed to obtain a more detailed insight into the deposition behavior of ultrafine particles. As clearly underlined by the model predictions, alveolar deposition depends on particle size, particle shape, and the mode of breathing. Highest deposition values may be attested for particles with aerodynamic diameters of about 10 nm. Smaller particles are subject to a highly effective filtering process in the extrathoracic region and upper bronchi, whereas larger particles are less affected by specific deposition forces and, thus, exhibit enhanced concentrations in the exhaled air. Deposition efficiency positively correlates with the inhalation flow rate or, in other words, ultrafine particles inhaled during sitting breathing are less effectively deposited in the alveoli than particles inspired during heavy-work breathing. Alveolar deposition of ultrafine particles may be regarded as serious criterion for the development of various lung diseases. Thereby, residence time of particles in the alveoli, particle biosolubility, and particle shape represent highly essential predictive parameters.

Author Details

Robert Sturm
Material Sciences and Physics, University of Salzburg

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