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Radon Progeny Microdosimetry in Human and Rat Bronchial Airways: The Effect of Crossfire From the Alveolar Region
Published
Author(s)
H Fakir, W Hofmann, Randall S. Caswell
Abstract
The objectives of the present study wee (i) to present a comprehensive analysis of the microdosimetric quantities in both human and rat bronchial airways and (ii) to assess the contribution of the crossfire alpha particles emitted from the alveolar region to bronchial doses. Hit frequencies, doses and critical microdosimetric quantities were calculated for basal and secretory cell nuclei located in different depths in epithelial tissue for each bronchial airway generation. Total doses and hit frequencies were consistently higher in rat airways than in corresponding human airways. The contribution of crossfire alpha particles is quite insignificant in the human lung, while it can reach 33% in peripheral bronchiolar airways of the rat lung. Such additional doses due to specifically high LET crossfire alpha particles may explain the observed tumor prevalence in the bronchiolar region. The presented microdosimetric information may help in understanding the differences in tumor occurrences in rates and humans, thus providing a more accurate extrapolation of animal data to humans.
Fakir, H.
, Hofmann, W.
and Caswell, R.
(2021),
Radon Progeny Microdosimetry in Human and Rat Bronchial Airways: The Effect of Crossfire From the Alveolar Region, Radiation Protection Dosimetry
(Accessed October 14, 2025)