Chapter Three

Concluding Remarks and Future Research

After examining the chemical and physical nature of DU, this report has surveyed the literature related to the health effects of DU through both external and internal exposure. Potential health effects were divided into those associated with radiation and with heavy-metal toxicology.

Few studies to date in the literature have focused directly on DU. On the other hand, there is a wealth of literature related to natural and enriched uranium. This literature provides many relevant insights because the heavy-metal chemical toxicity of DU is the same as that of natural and enriched uranium. Further, both natural and enriched uranium are far more radioactive than DU. Therefore, if no adverse health effects to natural uranium are reported, one may reasonably conclude the same will be the case for DU.

Radiation Effects

The literature review examined the extensive published data on radiation that has looked at the relationship between exposure to uranium through various pathways--inhalation, ingestion, and external exposure--and possible health effects. Available information includes data on human exposure to natural uranium through the normal pathways of diet and inhalation, studies of miners and millers in the uranium industry, findings on animals, and some studies relating directly to Gulf War veterans.

From the scientific literature it is concluded that:

Heavy-Metal Toxicological Effects

Uranium in the form of the isotopically depleted metal used for military purposes in the Gulf War presents primarily a potential chemical rather than radiological hazard. Like most heavy metals, uranium possesses a high chemical affinity for proteins and other biological molecules. It normally is taken up into the body through the lungs (via inhalation) or intestine (via ingestion) but in military settings may also penetrate the body as fragments. These slowly dissolve, posing a risk of chemical exposure.

The kidneys show special sensitivity to the chemical toxicity of uranium. While this does not exclude the possibility of the metal inflicting functional lesions in other organ systems, the first adverse chemical effects following high or prolonged exposure to uranium are found in the kidney. Proximal tubular function in particular is depressed, but lesions in other nephron segments have also been reported. In the case of high exposures, renal function can serve as a sensitive biomonitor.

The literature provides the following insights:


Although there is already a large body of literature on natural uranium, below we list some areas likely to prove fruitful in enhancing our knowledge of the health effects of DU. We encourage additional research into both the effects of exposure and long-term epidemiology studies to further our understanding of the health effects of DU. Among other research, the following areas of inquiry would be useful: In conclusion, the use of DU munitions and armor is likely to expand greatly over the coming years, both in the U.S. military and in other countries. It is therefore important to continue research to further our knowledge of any potential health risks that might result from different levels and pathways of exposure.

Previous Chapter
Next Chapter