GENEVA, Switzerland, April 26, 2001 (ENS) - The World Health Organization (WHO) today published research on depleted uranium, including guidelines on how to deal with the substance's impact on human health.

  Weapons made with depleted uranium (DU) pierce solid objects, like tanks, before erupting in a burning cloud of vapor. The vapor settles as dust, which is chemically poisonous and radioactive.

  "Depleted uranium has the potential to have chemical and radiological effects on health, but we found in the review that exposure to DU would have to be significant before any health effects are observed," said Dr. Mike Repacholi, WHO's coordinator for occupational and environmental health.

  WHO recommends measures are taken to prevent exposure of young children to depleted uranium because they may face particular risk.

  "Young children could receive greater depleted uranium exposure when playing within a conflict zone because of hand to mouth activity that could result in high depleted uranium ingestion from contaminated soil," said the WHO research. "This type of exposure needs to be monitored and necessary preventative measures taken."

  "Heavily affected DU munitions zones should be cordoned off and then cleaned up and treated as if any other heavy metal waste had contaminated the soil," added the organization.

  Uranium is a naturally occurring, ubiquitous, heavy metal found in various chemical forms in all soils, rocks, seas and oceans. It is also present in drinking water and food.

  Depleted uranium, a byproduct of nuclear power, has a density about twice that of lead, which has led to its use as counterweights or ballast in aircraft, radiation shields in medical equipment used for radiation therapy and containers for the transport of radioactive materials.

  Those same physical properties have seen DU used in munitions designed to penetrate armour plating and for reinforcement of military vehicles.

  First used in the Gulf War in 1990-1991, DU's possible health risks gained wider attention after its use during the Balkan conflict in 1998 and 1999.

  NATO is estimated to have fired 31,000 DU shells during the Kosovo campaign in 1998 and 1999. Some of that ammunition still litters Kosovo, and other parts of Yugoslavia.

  After a peace agreement in the summer of 1999, that saw Serb forces withdraw from Kosovo to be replaced by NATO peacekeepers, the United Nations set up the Balkans Task Force to assess the environmental damage of the Kosovo conflict.

  In response to a request from UN secretary general Kofi Annan and the United Nations Environment Program, NATO provided the exact coordinates of the target sites, enabling the task force to make proper measurements of DU sites in Kosovo.

  With help from other UN agencies, such as WHO, researchers hope to find out whether the use of depleted uranium during the conflict may pose health or environmental risks.

  "Depleted Uranium: Sources, Exposure and Health Effects," makes several recommendations regarding DU, which according to WHO, has 60 percent of the radioactivity of natural uranium and "significant chemical toxicity."

  WHO says it is not necessary to screen the general population in areas where DU munitions have been used.  But, it adds that those who believe they have been exposed to the substance should see a medical practitioner.

  "The greatest potential for DU exposure occurs after conflicts when people living or working in affected areas could inhale dust or consume contaminated food and drinking water," WHO said.

 The agency warns that after DU munitions are used, "in some instances the levels of contamination in food and groundwater could rise after some years and should be monitored and appropriate measures taken where there is a reasonable possibility of significant quantities of depleted uranium entering the food chain."

  "Potentially, DU has both chemical and radiological toxicity with the two important target organs being the kidneys and the lungs," said the WHO review, which notes that DU munitions have been used only relatively recently and the science has not yet thoroughly addressed the effects.

  The agency recommends further research, including studies to clarify the extent of kidney damage and its possible reversibility.