METHOD FOR THE DETERMINATION OF THORIUM AND URANIUM IN URINE BY ICP-MS

ICP-MS (inductively coupled plasma mass spectrometry) is shown as a ve ry sensitive method for quantitative determination of Th and U concent ration and excretion analysis in urine without any sample pretreatment . The current standard method for incorporation monitoring applies alp ha-spectrometry, a very tedious and time consuming technique. ICP-MS o ffers an attractive alternative for monitoring of thorium and uranium body burdens in occupationally exposed subjects and also larger groups of the general population. A limit of determination of 0.5 ng/L in aq ueous solutions and 1 ng/L in urine samples for both elements was achi eved, with a precision of about +/- 10% in the concentration range of appr. 10 ng/L. Due to the lack of a suitable reference material, the a ccuracy of the method was tested by comparing some of the results with those obtained by alpha-spectrometry, especially for U. There was a s ufficient agreement on both results.