Derivation and validation of a urinary excretion function for plutonium based on occupational exposure.

Formation of a three-component urinary excretion function using the data of occupational exposure cases is described. Measurement results of plutonium inhalation from two subjects over 6000 and 2500 d are used in the derivation of this function. The three-component excretion function obtained is U(t) = 0.0008e(-0.0566(t)) + 0.00009e(-0.0042(t)) + 0.00004e(-0.00008(t)). The function is therefore proposed as a reliable basis to make an uptake assessment for operational control for mixed class of plutonium dominated by M-class chronic exposure.