Local particle deposition patterns may play a key role in the development of lung cancer.
The apparent discrepancy between the reported preferential occurrence of bronchial carcinomas in central bronchial airways and current dose estimates for inhaled particles suggests that experimentally observed local accumulations of particles within bronchial airway bifurcations may play a crucial role in lung cancer induction. Here, we computed three-dimensional particle deposition patterns in lobar-segmental airway bifurcations and quantified the resulting inhomogeneous deposition patterns in terms of deposition enhancement factors, which are defined as the ratio of local to average deposition densities. Our results revealed that a small fraction of epithelial cells located at carinal ridges can receive massive doses that may be even a few hundred times higher than the average dose for the whole airway. This lends further credence to the hypothesis that the apparent site selectivity of neoplastic lesions may indeed be caused by the enhanced deposition of toxic particulate matter at bronchial airway bifurcations.
Balashazy
Imre
I
Radiation and Environmental Physics Department, KFKI Atomic Energy Research Institute, H-1525 Budapest 114, Hungary. ibalas@sunserv.kfki.hu
Hofmann
Werner
W
Heistracher
Thomas
T
D000336:Aerosols; D000393:Air Pollutants / Q000493:pharmacokinetics*; D001984:Bronchial Neoplasms / Q000473:pathology; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008175:Lung Neoplasms / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D008953:Models, Anatomic; D008954:Models, Biological; D010316:Particle Size; D012137:Respiratory System / Q000033:anatomy & histology / Q000378:metabolism*; D018570:Risk Assessment
D000336:Aerosols; D000393:Air Pollutants