Microdosimetry of radon progeny alpha particles in bronchial airway bifurcations.
A Monte Carlo code, initially developed for the calculation of microdosimetric spectra for alpha particles in cylindrical airways, has been extended to allow the computation of microdosimetric parameters for multiple source-target configurations in bronchial airway bifurcations. The objective of the present study was to investigate the effects of uniform and non-uniform radon progeny surface activity distributions in symmetric and asymmetric bronchial airway bifurcations on absorbed dose, hit frequency, lineal energy, single hit specific energy and LET spectra. In order to assess the effects of multiple hits, dose-dependent specific energy spectra were calculated by solving the compound Poisson process by iterative convolution. While the simulations showed significant differences of cellular dose quantities at different cell locations for uniformly distributed surface activities, even higher variations, as high as several orders of magnitude, were observed for non-uniform surface activity distributions, depending on the location of the cell and the local activity distribution.
Division of Physics and Biophysics, Department of Molecular Biology, University of Salzburg, Hellbrunner Strasse 34, A-5020 Salzburg, Austria. hatim.fakir@sbg.ac.at
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Hofmann
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Aubineau-Lanièce
D000396:Air Pollutants, Radioactive / Q000032:analysis*; D000512:Alpha Particles; D001980:Bronchi / Q000378:metabolism* / Q000528:radiation effects; D003198:Computer Simulation; D006801:Humans; D018499:Linear Energy Transfer; D008954:Models, Biological; D009010:Monte Carlo Method; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D017687:Radon Daughters / Q000032:analysis*; D018570:Risk Assessment; D012307:Risk Factors; D014018:Tissue Distribution
D000396:Air Pollutants, Radioactive; D017687:Radon Daughters