Validated measurement of uranium in a human urine standard reference material by ICP-MS with the standard addition method

The Urine Analysis Laboratory of the Korea Atomic Energy Research Institute has developed an in vitro method for measuring uranium in spot urine samples using inductively coupled plasma-mass spectrometry (ICP-MS) with microwave-assisted digestion and standard addition. To validate this procedure, the frozen human urine standard reference material (SRM 2668), such as uranium and creatinine, were analyzed. To overcome the matrix effect and thereby obtain precise measurement data, the standard addition method with extrapolation of four additional points was applied. The measured values for uranium in the SRM were within the acceptable margin of error. The results were compared and evaluated with respect to the American National Standards Institute and Heath Physics Society (ANSI/HPS) N13.30 and International Organization for Standardization 28218 standards. The relative precision (S_Br), relative bias (B_r), and root-mean-square error values were within the acceptable ranges for the SRM. (authors)