presented here come primarily from a case series of Gulf War veterans who participated in the Depleted Uranium Follow-up Program at the BVAMC and from studies of uranium-processing workers and well-water users in Finland.

Mortality from diseases of the circulatory system was significantly lower in most studies of uranium-processing workers, probably because of the healthy-worker effect. Pinkerton and colleagues reported statistically significantly fewer deaths from heart disease than expected (SMR, 84; 95% CI, 75-94) in a cohort of uranium-mill workers in the Colorado Plateau region (Pinkerton et al., 2004). Similarly, workers employed in the FFMPC had lower cardiovascular mortality than the US white male population (SMR, 78; 95% CI, 71-86) (Ritz, 1999). Mortality from circulatory diseases in workers at the Mallinckrodt processing plant (SMR, 89; 95% CI, 81-97) (Dupree-Ellis et al., 2000) and the Rocketdyne/Atomics International (SMR, 68; 95% CI, 58-78) (Ritz et al., 2000) was significantly lower than that in white males in the United States. Results of experimental studies that used exceedingly high doses of uranium in several animal models suggest that the cardiovascular system is not a sensitive target for this metal.

McDiarmid and colleagues (2001) found a statistically significant increase in mean sister-chromatid exchanges (SCEs) (6.35 ± 0.267 vs 5.52 ± 0.182; p = 0.03) in cultured peripheral-blood lymphocytes from members of the high-urinary-uranium group in the 1999 medical surveillance of depleted-uranium–exposed Gulf War veterans. The association remained after adjustment for current smoking status. A statistically significant difference between low- and high-exposure groups was also seen in mean SCEs at high doses of bleomycin; the high-exposure group had increased SCEs (6.25 ± 0.338 vs 4.88 ± 0.262; p = 0.01). No differences were observed in tests for chromosomal aberrations. The findings suggest a possible genotoxic effect; however, as the authors suggest, additional surveillance was needed to establish a clinical association. In the 10-year postwar followup assessment, the authors reported a statistically significant increase in the mean frequency of chromosomal aberrations in the high-urinary-uranium group (McDiarmid et al., 2004). However, the 12- and 14-year assessments revealed no statistical differences in chromosomal aberrations between high- and low-urinary-uranium groups. Hypoxyanthine-guanine phosphoribosyl tranferase mutation frequencies measured at 10, 12, and 14 years were nonsignificantly greater in the high-exposure group than in the low-exposure group.