title: Mucosal structure and radon in head carcinoma dosimetry.
abstract: (1) The location of the epithelial cells implied by ICRP Publication 26 is incorrect. It leads to dose rates from bone and to dose rate ratios which are much too high. (2) Epithelial thickness has little effect on the ratio of dose rates. (3) The dose rate ratio is strongly dependent on the thickness of the lamina propria and would depend strongly on the thickness of the cytoplasm layer if direct nuclear hits were required for cell transformation. (4) Based on the limited data available for lamina propria and epithelial thicknesses, the airspaces would probably be the dominant source of dose in the mastoid air cells if the ratio of radioactivity levels in bone and airspace were no more than 1 l./g. This would be true whether targets were spread throughout the whole cell or confined to the nucleus alone. (5) The airspaces would probably be the dominant source of dose in the paranasal sinuses if the ratio of radioactivity levels were no more than 1 l./g. and targets were spread throughout the cell. If targets were confined to the nucleus, no conclusion could be drawn due to the lack of information on the thickness of the nucleus-free region of cytoplasm. (6) Four quantities require further study for a better understanding of the importance of radon: (a) the airspace radon concentration, (b) the specific activity of bone adjacent to the mucous membrane, (c) the thickness of the nucleus-free region of cytoplasm, and (d) the thickness of the lamina propria.
mesh_terms: D000388:Air; D000512:Alpha Particles; D006258:Head and Neck Neoplasms / Q000209:etiology*; D006801:Humans; D008416:Mastoid / Q000033:anatomy & histology; D009092:Mucous Membrane / Q000033:anatomy & histology; D009381:Neoplasms, Radiation-Induced / Q000209:etiology*; D010256:Paranasal Sinuses / Q000033:anatomy & histology; D011829:Radiation Dosage; D011886:Radon
chemical_list: D011886:Radon