The redefinition has a morphologic and physiological basis and is consistent with observed deposition and clearance of particles and with resultant pathology.
Regions, as revised, are the extrathoracic (E-T) region, comprising the nasal and oral regions, the pharynx, larynx, and upper part of the trachea; the fast-clearing thoracic region (T[f]), comprising the remainder of the trachea and bronchi; and the slow-clearing thoracic region (T[s]), comprising the bronchioles, alveoli, and thoracic lymph nodes.
In 1984, the International Commission on Radiological Protection (ICRP) appointed a task group of Committee 2 to review and revise, as necessary, the ICRP Dosimetric Model for the Respiratory System. The task group concluded that research during the past 20 y suggested certain deficiencies in the ICRP Dosimetric Model for the Respiratory System.The model was originally published in 1966, modified slightly in Publication No. Research has also provided sufficient information for a revision of the model.This report provides reviews of information on the transit of materials through the alimentary tract and on radionuclide retention and absorption.It considers data on health effects, principally in order to specify the target cells for cancer induction within the mucosal lining of the tract and to justify approaches taken to dose averaging within regions.It could be something as simple as a run away script or learning how to better use E-utilities, for more efficient work such that your work does not impact the ability of other researchers to also use our site.
To restore access and understand how to better interact with our site to avoid this in the future, please have your system administrator contact [email protected] and median estimates were calculated for f for each plutonium compound, that can be used as default values for specific chemical forms instead of the current reference types.Nevertheless, it was shown that the use of the current ICRP reference absorption types provides reasonable approximations.Your access to the NCBI website at gov has been temporarily blocked due to a possible misuse/abuse situation involving your site.This is not an indication of a security issue such as a virus or attack.The new human alimentary tract model (HATM) will be used together with the human respiratory tract model (HRTM) in future ICRP publications on doses from ingested and inhaled radionuclides.