Plutonium Biokinetics in Human Body A. Luciani - Kit-Bibliothek - FZK

own biokinetic. Therefore Americium own systemic model, as provided by ICRP [2], was
assumed in this scenario of contamination.
Table 3.2.1 Different possible assumptions for the absorption types and systemic models for
Plutonium and Americium (directly inhaled and due to the ingrowth from 241 Pu
decay).
Radionuclide Scenario 1 Scenario 2 Scenario 3
Type Model Type Model Type Model
Pu, all the isotopes S Model-b M Model-b S Model-b
241 Am from 241 Pu decay S Model-b M Model-b M ICRP 67
241 Am directly inhaled M ICRP 67 M ICRP 67 M ICRP 67
Predictions of Americium activity in lungs were calculated for each of the considered
scenarios of Table 3.2.1. On the basis of the experimental data for Americium activity
retained in lungs, intakes were evaluated first. The intake was evaluated by minimizing the
value of the F target function, written according to equation 3.1.7, where the model’s
predictions for e u(t) are now substituted by the Americium activity retained in lungs per unit
of intake and the experimental values are given now by the measurements of Americium in
lungs. The evaluated intakes were then multiplied by the model’s predictions of Americium
retained in lung per unit of intake. The resulting values are presented with the available
measurements for comparison purposes in Figure 3.2.1, Figure 3.2.2 and Figure 3.2.3 for the
scenarios of contamination number 1, 2 and 3, respectively (Table 3.2.1). In the same figures
the single contributions to Americium burden in lung (Americium directly inhaled and from
241 Pu decay) are also plotted.
Americium in the lungs [Bq]
1000
100
10
Measurements
Model total retention
Directly inhaled 241Am
241 241
241Am Am from from Pu 241Pu decay decay
241 Am
1 10 100 1000 10000 100000
Days post intake
Figure 3.2.1 Measurements and model predictions for Americium activity retained in lungs
for the scenario 1 (see Table 3.2.1).
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