Alpha particle spectra and microdosimetry of radon daughters
- National Institute of Standards and Technology, Gaithersburg, MD (United States)
We are interested in understanding the physics of the process by which radon-daughter alpha particles irradiate cells, leading to the induction of cancer. We are focusing initially on two aspects: the alpha spectra incident upon cells, which are needed for input to biophysical models of cancer induction; and microdosimetric spectra and parameters which give information on radiation quality. Adapting an analytical method previously developed for neutron radiation, we have calculated the alpha-particle slowing-down spectra (the spectra incident upon cells) and, subsequently, the microdosimetric spectra and parameters for various cell nuclei or site diameters. Results will be presented from three modes of program operation. MODE 1 is for the thin, plane source of radon-daughter activity adjacent to the epithelium. MODE 2 is for the thick source layer (the mucous-serous layer) adjacent to the epithelium. MODE4 is for cylindrical airways of various radii, lined by the mucous-serous layer. MODE 1 is most useful for understanding the problem; MODE 4 is most anatomically relevant. MODE 3 is not discussed in this paper. Alpha-particle spectra and microdosimetric spectra and parameters are studied as a function of cell depth, {sup 218}Po/{sup 214}Po ratio, airway radius, and cell nucleus or the site size. Also available from the calculation is mean dose as a function of depth below the airway surface. The results described here are available on personal computer diskettes. We are beginning to compare our studies with the calculations of other workers and plan to extend the calculations to the nanometer target level.
- OSTI ID:
- 45164
- Report Number(s):
- CONF-901010-Pt.1; TRN: 95:003574-0015
- Resource Relation:
- Conference: 29. Hanford symposium on health and the environment: indoor radon and lung cancer--reality or myth, Richland, WA (United States), 15-19 Oct 1990; Other Information: PBD: 1992; Related Information: Is Part Of Indoor radon and lung cancer: Reality or Myth? Part 1; Cross, F.T. [ed.]; PB: 527 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Energy deposition and radiation quality of radon and radon daughters. Final report
Model for assessing radiation dose to epithelial cells of the human respiratory tract from radon progeny