Thirty years of surveillance of depleted uranium-exposed Gulf War veterans demonstrate continued effects to bone health.

During the spring of 2024, 33 members of a group of Gulf War I veterans wounded in depleted uranium (DU) friendly-fire incidents were seen at the Baltimore VA Medical Center for surveillance related to their combat exposure. The cohort was assessed with a protocol which includes exposure monitoring for total and isotopic uranium (U) concentrations in urine and a comprehensive assessment of health outcomes including measures of bone metabolism and bone mineral density (BMD). An audiometry examination of the cohort was added to assess for acoustic trauma and toxic metal effects in this surveillance episode marking over 30 years since this exposure event. Elevated urine U concentrations were detected in cohort members with retained DU shrapnel fragments. In addition, a measure of bone resorption, N-telopeptide, determined in urine, exhibited a significant increase in the high DU sub-group. In addition, and similar to our previous surveillance report, a significant decrease was found in bone mass in the high DU sub-group compared to the low DU sub-group. It has been 30 years since the first surveillance visit occurred. An aging cohort of military veterans continues to demonstrate few U-related adverse health effects in known target organs attributed to U toxicity exposure. The new finding of impaired BMD in older cohort members has now been detected in three consecutive surveillance visits. This is a biologically plausible outcome related to the diminished bone mass in those with an elevated DU burden in combination with advancing age. The accumulating U burden derived from fragment absorption over time and the effect of aging on bone mineral loss recommends that our surveillance efforts need to continue. Our findings enable early detection of bone effects and other signs of target organ insult, which may occur when tissue injury thresholds are reached in the future and thus, permitting indicated medical management.