Answer to Question #1101 Submitted to "Ask the Experts"

Q

What is your opinion, as a professional health physicist, about the use of depleted uranium (DU) ammunition in war operations?

A

Human health risks from exposure to DU can be broadly categorized in terms of radiological or chemical toxicity. Because of DU's low radioactivity or specific activity, a very high exposure is required to increase the radiological risk. For example, an acute inhalation of gram quantities of respirable DU aerosol would be needed. This would only be possible for soldiers present in armored vehicles struck by DU penetrators. Exposure of the general public to environmentally dispersed DU may pose a risk of chemical toxicity depending on the level of exposure, primarily from ingestion. At a recent experts' workshop on DU in the Balkans (Bad Honnef Germany; see the Health Physics Society's Newsletter, September 2001 for details), United Nations scientists studying the environmental behavior of DU showed that DU dissolving from penetrators embedded in soil did not migrate more than 20 cm from the source and that a very small fraction of the DU had dissolved. They did not find any DU contamination in milk, well water, houses, or vehicles in areas where DU munitions were used, nor was any DU measured in urine samples taken from soldiers who were deployed in regions where DU was used. Because evidence indicates that human exposures to DU will be very small, and that these levels will be small fractions of the public's routine exposure to natural uranium, predicted health effects appear to be inconceivable.

Raymond A. Guilmette, PhD