Determination of Occupational Exposure to Depleted Uranium Based on Inductively Coupled Plasma Mass Spectrometry.

Abstract : We used a simple method based on inductively coupled plasma mass spectrometry (ICP-MS) to determine the isotopic composition of uranium in urine at levels that indicate occupational exposure to depleted uranium (DU). DU exposure is indicated by a range for U-235 between 0.72 and 0.2 percent. Using the ICP-MS isotopic ratio method, we determined the percentage of U-235 in a series of urine samples based on the measured intensities of the U-235 and U-235 ions. In this study, urine samples from 12 individuals suspected of having been exposed to DU were processed by the Armed Forces Radiobiology Research Institute (AFRRI) and then analyzed by ICP-MS at the Army Research Laboratory for the presence of DU. We achieved a lower detection limit of 14 ng L/cm in the original urine samples, which is at or near uranium levels in the general population (not occupationally exposed to uranium). We concluded that this approach can be used to determine the percentage of U-235 in urine samples characterized by higher than normal uranium levels, and thus whether occupational exposure to DU has occurred.