Deposition and retention of ultrafine aerosol particles in the human respiratory system. Normal and pathological cases.
The particle number concentration in ambient air is dominated by nanometer-sized particles. Recent epidemiological studies report an association between the presence of nanoparticles in inhaled air at the workplace and acute morbidity and even mortality in the elderly. A theoretical model of deposition of 20 nm particles in the human alveolus was formulated. Gas flow structure and deposition rate were calculated for alveoli with different elastic properties of lung tissue. Data obtained in the paper show increased convective effects and diffusional rate of deposition of nanoparticles for alveoli with higher stiffness of the alveolar wall. The retention of deposited particles is also higher in these pathological alveoli. Results of our calculations indicate a possibility of existence of a positive loop of coupling in deposition and retention of nanoparticles in the lung with pathological changes.
Department of Chemical and Process Engineering, Warsaw University of Technology, Poland. gradon@ichip.pw.edu.pl.
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Gradoń
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Orlicki
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Podgórski
D000336:Aerosols; D000397:Air Pollution / Q000009:adverse effects*; D018481:Convection; D004058:Diffusion; D004784:Environmental Monitoring / Q000379:methods*; D004812:Epidemiologic Methods; D062665:Epidemiological Monitoring; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects*; D008170:Lung Compliance / Q000502:physiology*; D008954:Models, Biological; D009017:Morbidity; D009784:Occupational Diseases / Q000453:epidemiology / Q000209:etiology*; D010316:Particle Size; D012143:Respiratory Physiological Phenomena; D012140:Respiratory Tract Diseases / Q000453:epidemiology / Q000209:etiology*
D000336:Aerosols