Dosimetry model for bronchial and extrathoracic tissues of the respiratory tract

Conference · Wed Oct 31 23:00:00 EST 1990

OSTI ID:6035462

James, A C; Cross, F T; Durham, J S; Briant, J K ^[1]; Gehr, P ^[2]; Masse, R ^[3]; Cuddihy, R G ^[4]

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1. Pacific Northwest Lab., Richland, WA (USA)
2. Bern Univ. (Switzerland). Anatomisches Inst.
3. CEA Centre d'Etudes Nucleaires de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire
4. Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (USA). Inhalation Toxicology Research

The Task Group to Review the Lung Model for the International Commission on Radiological Protection (ICRP) is proposing to revise the dosimetry model for the respiratory tract on the basis of the relative radiosensitivities of the various tissue components. The task group considers that if all tissues were to receive the same radiation dose, approximately 64% of fatal cancers would be likely to arise in the bronchi, about 12% in the bronchioles, about 20% in extrathoracic tissues (divided between the naso-- and oropharynx and larynx), and only about 4% in the alveolar-interstitial tissue, with a very small fraction of all cancers (less than 0.1%) in lymph nodes. A new and detailed treatment of dose received by epithelia in the tracheo-bronchiolar and extra-thoracic regions of the respiratory tract is therefore required. This paper describes the approach proposed by the task group to evaluate doses to presumed target cells in each of these tissues at risk in the respiratory tract from non-uniform irradiation by {alpha}-, {beta}- and electron-emitters. The task group's approach takes into account the impact of observed phenomena that may cause long-lived radionuclides to be retained in epithelial tissues: the uptake of particles by the airway wall; the chemical binding of sparingly soluble nuclides in epithelial tissues; and, especially in the bronchi and bronchicles, the slow clearance of particles by mucus. Values of dose, weighted by the task group's proposed relative risk factors are calculated for several types of {alpha}- and {beta}- emitters. These weighted doses are compared with the committed effective dose equivalent calculated using the current ICRP lung model, in which the simplifying assumption is made that all of the activity retained in the thorax uniformly irradiates the 1 kg mass of a composite'' lung. 11 refs., 14 figs., 7 tabs.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA)
• Sponsoring Organization: DOE/EH
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6035462
• Report Number(s): PNL-SA-18334; CONF-900733--6; ON: DE91006890
• Country of Publication: United States
• Language: English

Related Subjects

551000 -- Physiological Systems
560151* -- Radiation Effects on Animals-- Man
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
AGE DEPENDENCE
ALPHA DECAY RADIOISOTOPES
ANIMAL CELLS
ANIMAL TISSUES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL ACCUMULATION
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOPHYSICS
BODY
BRONCHI
CELL TRANSFORMATIONS
CLEARANCE
COBALT 60
COBALT ISOTOPES
COMPARTMENTS
DAYS LIVING RADIOISOTOPES
DOSE EQUIVALENTS
DOSES
DOSIMETRY
EPITHELIUM
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
HEAVY NUCLEI
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
IRON 59
IRON ISOTOPES
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LIGHT NUCLEI
LOCAL RADIATION EFFECTS
MATHEMATICAL MODELS
MINUTES LIVING RADIOISOTOPES
NANOSEC LIVING RADIOISOTOPES
NUCLEI
ODD-ODD NUCLEI
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PLUTONIUM 239
PLUTONIUM ISOTOPES
POLONIUM 210
POLONIUM ISOTOPES
RADIATION DOSES
RADIATION EFFECTS
RADIOISOTOPES
RADIOSENSITIVITY
RESPIRATORY SYSTEM
RESPIRATORY TRACT CELLS
RETENTION
SEX DEPENDENCE
TISSUES
URANIUM 238
URANIUM ISOTOPES
YEARS LIVING RADIOISOT
YEARS LIVING RADIOISOTOPES