Flow injection extraction chromatography with ICP-MS for thorium and uranium determination in human body fluids

A method based on flow injection extraction chromatography coupled to on-line ICP-MS (FI-EXC-ICPMS) has been developed and validated for simultaneous thorium and uranium determination in human body fluids. By using extraction chromatography, the limits of detection achieved for ²³²Th, ²³⁵U and ²³⁸U were 0.06 ng^.l^-1, 0.0014 ng^.l^-1 and 0.05 ng^.l^-1, respectively. The accuracy of the FI-EXC-ICPMS method was 102.4% and 101.5% with overall precision (RSD_max at 95% CI) of 5.3% and 4.9% for ²³²Th and ²³⁸U, respectively. The ²³⁵U/²³⁸U atom ratio is measured with 1.8% precision. The technique was employed for simultaneous thorium and uranium analyses in human urine and blood samples after microwave digestion. This revised version was published online in July 2006 with corrections to the Cover Date.