title: Analyses of local dose distributions in the lungs for the determination of risk apportionment factors.
abstract: For radiation protection purposes, the relative contributions of bronchial (BB), bronchiolar (bb) and alveolar-interstitial (AI) doses to lung cancer risk are represented by their corresponding apportionment factors. The current assumption of equal apportionment factors can be tested by comparing different radon and thoron progeny exposures, which produce different regional dose distributions, with the pathologically observed regional cancer distributions: (1) radon progeny inhalation, (2) thoron progeny inhalation, (3) thoron and thoron progeny exhalation (Thorotrast patients) and (4) RP inhalation in rats, and cigarette smoke inhalation as smoking is the dominant cause of lung cancer. Comparison with the pathologically observed regional cancer distributions suggests (1) a smaller apportionment factor for the AI region as compared with BB and bb regions and (2) a higher value for the BB region relative to that for the bb region.
authors.affiliation: Department of Materials Research and Physics, University of Salzburg, Hellbrunner Str. 34, Salzburg 5020, Austria.
authors.forename: R
authors.initials: R
authors.lastname: Winkler-Heil
authors.affiliation: Department of Materials Research and Physics, University of Salzburg, Hellbrunner Str. 34, Salzburg 5020, Austria werner.hofmann@sbg.ac.at.
authors.forename: W
authors.initials: W
authors.lastname: Hofmann
authors.affiliation: Department of Materials Research and Physics, University of Salzburg, Hellbrunner Str. 34, Salzburg 5020, Austria Higher Education Commission of Pakistan, Islamabad 44000, Pakistan.
authors.forename: M
authors.initials: M
authors.lastname: Hussain
authors.affiliation: Department of Materials Research and Physics, University of Salzburg, Hellbrunner Str. 34, Salzburg 5020, Austria.
authors.forename: L
authors.initials: L
authors.lastname: Pichelstorfer
mesh_terms: D065638:Absorption, Radiation; D000280:Administration, Inhalation; D000328:Adult; D000396:Air Pollutants, Radioactive / Q000032:analysis*; D016902:Air Pollution, Indoor / Q000032:analysis*; D000818:Animals; D003198:Computer Simulation; D006801:Humans; D008168:Lung / Q000737:chemistry*; D008297:Male; D008954:Models, Biological; D015233:Models, Statistical; D011829:Radiation Dosage; D000069079:Radiation Exposure; D011874:Radiometry / Q000379:methods*; D011886:Radon / Q000008:administration & dosage / Q000032:analysis*; D051381:Rats; D018570:Risk Assessment / Q000379:methods; D014018:Tissue Distribution
chemical_list: D000396:Air Pollutants, Radioactive; D011886:Radon