Estimation of lung absorption parameters for oxides of 238 Pu

Following inhalation of an aerosol of relatively insoluble particles, it is usually found that the fractional dissolution rate of material retained in the lungs decreases with time, and the amount remaining undissolved can be represented simply by a decreasing exponential function with two or more components. A few exceptions are known, in which the dissolution rate increases with time. The most important in the context of radiological protection is probably that of 238 Pu dioxide. Several published comprehensive data sets, from animal studies and accidental human exposures, have been analysed using the Human Respiratory Tract Model (HRTM) of the International Commission on Radiological Protection. The HRTM contains a simplified representation of particle dissolution in the respiratory tract, suitable for routine radiological protection purposes. Still, it was found to have sufficient flexibility to represent the measurement data in most of these cases. Although the
Source: Journal of Radiological Protection - Category: Physics Authors: Source Type: research