Urinary Excretion of Uranium

DOE-STD-1136-2004

Guide of Good Practices for Occupational Radiological Protection in Uranium Facilities

where ras(t)is the systemic retention per unit intake and t is the time in days after intake of uranium. Of the

uranium entering the transfer compartment, 0.673 is directly excreted (Tb of 0.25 d), 0.007 is translocated

to red blood cells (Tb of 1.1 d), 0.08 is translocated to kidneys (Tb of 6 d), 0.07 is translocated to soft

tissues (Tb of 26 d), and 0.15 and 0.02 are translocated to mineral bone (Tb of 300 and 3700 d,

respectively). The parameter values for this function are summarized in Table 5-10.

Table 5 -10. Fisher-Modified Wrenn-Lipsztein Uranium Model Parameter Values(a)

Organ(s)

Coefficient

Fraction

Half-Life (d)

Excretion

0.673

1.0

0.25

Red blood cells

0.007

1.0

1.1

Kidneys

0.08

1.0

Soft tissues

0.07

1.0

Bone

0.17

0.88

300

0.12

3,700

(a) (Fisher et al., 1991)

5.6.3.3 Urinary Excretion of Uranium

There currently are three possible urinary excretion functions for uranium compounds: the ICRP

Publication 30, Wrenn-Lipsztein, and the Fisher-Modified Wrenn-Lipsztein models. Professional

judgement must be used in selecting one of these functions as the primary function to be used in routine

bioassays in this internal dosimetry program and as the function of choice in individual dose assessments.

The value of fractional urinary excretion used to evaluate bioassay data is f u = 1.0 (ICRP, 1988b).

5.6.3.4 ICRP Publication 30 Uranium Urinary Excretion Function

The derivative of the ICRP uranium retention function with respect to time multiplied by a urinary

excretion fraction (fu) of 1.0 describes the urinary excretion of uranium. The urinary excretion is as

follows:

(5.3)

where e iu(t) is the fractional urinary excretion rate per unit intake as a function of time t after a single

intake of uranium. The parameter values for this function are summarized in Table 5-11.

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