A recently published radiotoxicological technique makes it possible to detect traces of uranium in urine in routine monitoring. This technique was used in an experimental study carried out with several volunteers to check ICRP uranium metabolism data. The volunteers agreed to consume natural mineral water containing uranium. It is shown that: (1) except for the initial components, which are clearly over-estimated, the theoretical urinary excretion function is acceptable; and (2) the nominal intestinal uptake of the soluble uranium components should be significantly lowered.