The utility of spot collection for urinary uranium determinations in depleted uranium exposed gulf war veterans

The utility of spot urine collections for uranium bioassay determinations was examined in a small cohort of depleted uranium exposed Gulf War veterans. Some members of the group are excreting elevated concentrations of urinary uranium resulting from the metabolism of retained metal fragments, the residua of several friendly fire incidents. Uranium determinations were performed on both 24-h timed collections and spot urine samples using kinetic phosphorescence analyzer (KPA) methodology. Results ranged from non-detectable to 30.7 mcg g^-1 creatinine in a 24-h collection. A creatinine-standardized spot sample and a 24-h uncorrected sample both correlated highly (R²=0.99) with a creatinine corrected 24-h collection, presumed to be the best estimate of the urinary uranium measure. This relationship was upheld when the population was stratified by uranium concentration into a high uranium group (≥0.05 mcg U/g creatinine) but for the lower uranium group (