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Page Title:
Fisher-Modified Wrenn-Lipsztein Uranium Systemic Retention Function |
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|  DOE-STD-1136-2004
Guide of Good Practices for Occupational Radiological Protection in Uranium Facilities
where t is the time in days after intake of uranium. Of the uranium entering the transfer compartment, 0.54
is directly excreted (T of 0.25 d), 0.2 and 0.023 are translocated to mineral bone (T of 20 and 5000 d,
b
b
respectively), 0.12 and 0.00052 are translocated to the kidneys (T of 6 and 1500 d, respectively), and
b
0.12 and 0.00052 are translocated to all other tissues (T of 6 and 1500 d, respectively).
b
5.6.3.2 Fisher-Modified Wrenn-Lipsztein Uranium Systemic Retention Function
The Fisher-Modified model (Fisher et al., 1991) consists of modifications of clearance half-times from
two biokinetic models: the ICRP Publication 30 respiratory tract model (ICRP 1979) and the Wrenn-
Lipsztein recycling model for systemic uranium (Wrenn, et al. 1989). As shown in Table 5-9, the clearance
half-time of uranium from ICRP Publication 30 lung compartment e to the blood is changed from 0.5 d to
0.03 d or 45 min. The clearance half-time of uranium from the kidney to urine in the Wrenn-Lipsztein
urinary excretion model is changed from 15 d to 6 d.
Table 5 -9.
Mathematical Model to Describe Clearance from the Respiratory Tract for the Fisher-
Modified Wrenn-Lipsztein Uranium Urinary Excretion Modela)
(
Class D
Fast or
Slow
Region
FR
T (d)
F
N-P
0.30
0.01
0.5
F
0.01
0.5
F
0.08
0.01
0.95
F
0.2
0.05
F
0.03(b)
P
0.25
0.8
S
NA
NA
F
NA
NA
S
0.5
0.2
S
L
NA
0.5
1.0
S
NA
NA
---
(a) FR = Regional fractions; T = Removal half-times (d);
F = compartmental fractions for each of the three classes of retained materials; and NA = not applicable.
(b) Modified from ICRP 30 (ICRP 1979) value of 0.5 d.
The function for the Fisher-Modif ied Wrenn-Lipsztein Model is as follows:
(5.2)
5-24
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