Related Experiment Video
Updated: Aug 13, 2026

Modeling and Simulations of Olfactory Drug Delivery with Passive and Active Controls of Nasally Inhaled Pharmaceutical Aerosols
Published on: May 20, 2016
Electron absorbed fractions based on a new model of the anterior nasal passage
H M Moussa1, K F Eckerman, L W Townsend
1University of Tennessee, Radiological Safety Department, Knoxville, TN 37996, USA. hmoussa@utk.edu
Abstract:
In a previous work we reported that the fraction of the electron energy absorbed in the basal cell layer of the anterior nasal passages was not very sensitive to changes in the surface area or radius of the cylindrical model adopted in Publication 66 of the International Commission on Radiological Protection. These absorbed fraction data are used in calculation of the dose to a 10-microm-thick basal cell layer located at a depth of 40 microm in the epithelial cell layer of the extrathoracic (ET1) region. However, these data may only be applicable to the assumed cylindrical geometry and may not be valid for more realistic ET1 geometries. The nose differs in size and shape from one person to another, its shape is not cylindrical but closer to a truncated elliptical cone, and in most humans the nostrils are elliptical in shape. We propose herein a more realistic geometry model, the frustum of a cone, for the anterior nose region (ET1) as an alternative to the cylinder model provided in ICRP 66. The results of absorbed fraction calculations using MCNP4B with the new model are reported. These absorbed fractions are compared to the values previously obtained using the MCNP4B code and a cylindrical model (10 cm2 surface area). We also investigate the effects of changing the size of the truncated cone to represent variations due to sex and age.
Related Concept Videos
Electron Orbital Model
The Bohr Model
The Quantum-Mechanical Model of an Atom
Electron Behavior
Electrons Orbit the Nucleus
Electrons are found in specific locations outside of the nucleus. The shell in which an electron resides indicates the general energy level of the electron: those closer to the nucleus have less energy,...
Thomson's e/m Experiment
A particle with charge q, speed v, and mass m enters an area from the top, where the magnetic and electric fields are perpendicular both to the particle's motion and to one another. The magnetic...
Nose and Nasal Cavity

