A set of tabulated values [math]m_{(t)}[/math] predicted by a reference biokinetic model describing the time course of the activity in the body (‘retention function’) or the activity excreted in urine or faeces (‘excretion function’) following an acute intake at time [math]t_0[/math]. A retention function [math]m_{(t)}[/math] represents the predicted activity of a radionuclide in the body, organ, or tissue at a time t after the intake, whereas an excretion function [math]m_{(t)}[/math] represents the predicted activity of a radionuclide in a 24-h excreta sample at a time t after the intake. (Adapted fromICRP Publication 130, 2015)
ICRP Glossary entry - May 2019