This is some of what RAND has to say about it. Nowhere in this site do they say that it is safe. They say that studies conducted so far do not show correlations between some of the conditions being examined and certain health consequences. But they also say that more research is needed (on people who have already been exposed) in order to determine more conclusively what the possible health hazards are:

"Because risk assessment has advanced greatly since many of the standards for both occupational and population exposures were developed, reexamination of those standards and refined dose response end points by these organizations would be helpful.

Research to better understand the mechanisms and dose response of exposure to DU on renal function would be helpful. Attempts should be made to correlate nephrotoxicity with renal uranium concentration following different modes and levels of exposure. Knowledge of cortical concentration would be more informative than total renal uranium levels. The U.S. Transuranium Registry is a continuing source of these data (Kathren and Ehrhart, 1998). It is also important to continue work to understand the mechanism by which natural and depleted uranium exert toxic effects on the body. This would include work to understand the nature and toxicological significance of the separate uranium pools kinetically identified in the kidney. Modern techniques should permit analysis of distribution of the toxic metal in the kidney, and more-sophisticated dose-effect studies than those relying on total tissue concentration at one arbitrary time are appropriate.

The work of the DU Follow-Up Program being conducted and expanded at the Baltimore VA Medical Center is important and needs to continue. The cohort and research represents the best opportunity to study the effects of human exposure to DU over time that is now available.

Although ionizing radiation from DU is in the form of alpha particles, the decay products emit gamma and beta radiation that could affect those in proximity to DU weapons. Although research to date has indicated that levels of exposure are significantly below occupational levels, ongoing efforts to study the levels of exposure from such radiation to soldiers in proximity to DU weapons or armor should continue, especially as weapons and weapon systems vary over time."

RAND