Surveillance of Gulf War I veterans exposed to depleted uranium: 15 Years of follow-up

Aim. To provide a summary of selected findings from the Depleted Uranium (DU) Follow-Up Program surveillance fifteen years after exposure to DU during the Gulf War. Patients and methods. A dynamic cohort of seventy-four 1991 Gulf War soldiers with known exposure to DU resulting from their involvement in "friendly-fire" incidents with DU munitions is being followed by the Baltimore Veterans Affairs Medical Center. Biennial medical surveillance visits designed to identify uranium-related changes in health have been conducted since the early 1990s. Ongoing systemic exposure to DU in veterans with embedded metal fragments is indicated by elevated urine uranium (U) excretion at concentrations up to 1,000-fold higher than that seen in the normal population. Typically, urine U concentration is determined at the time of each surveillance visit. During the 2005 visit, a cumulative measure of U exposure was also calculated based on each veteran's past urine U concentrations since first exposure in 1991. Results. Using either exposure metric, results continue to show no evidence of clinically significant uranium-related health effects. Particular interest in proximal tubule and other renal parameters, the presumed critical organ targets for U toxicity, have not shown any differences when examined by stratifying the cohort into high-versus-low (normal) U groups. There is some evidence of a weak genotoxic effect from the ongoing DU exposure as measured at the HPRT (hypoxanthine-guanine phosphoribosyl transferase) locus, and as suggested by the fluorescent in-situ hybridization (FISH) results in peripheral blood, that recommends the need for continued surveillance of this population. Conclusions. The continued evidence of genotoxic effects, albeit relatively weak effects, recommends the need for continued surveillance of this population.