ZURICH (Reuters) - A Swiss laboratory has found only minute traces of plutonium in NATO depleted uranium (DU) weapons used by NATO-led forces in the Balkans, Swiss radio reported on Wednesday.

``It is already clear that only extremely small -- if any -- traces of plutonium were found in the shells and shell fragments that were checked, and these in no way pose a potential health risk, according to scientists,'' the radio reported.

The possible danger of contamination from armor and other targets hit by cheap and highly-effective shells tipped with depleted uranium during the Gulf War -- and more recently in southern Serbia -- has caused an outcry in some Western states. Britain and the United have insisted the risks are minimal.

Swiss defense ministry spokesman Oswald Sigg told the radio: ``We will release the detailed findings of the Spiez (weapons lab) plutonium investigation this week, but we can already confirm the same trend that the German investigation found.''

He was referring to reports that Germany's GSF research lab had also found no traces of highly toxic plutonium in NATO ammunition used in the Balkans.

Last month Switzerland ordered the lab to check DU weapons samples from Kosovo for plutonium amid concern -- played down by defense experts -- that the munitions may have posed health risks to peacekeepers, aid workers and civilians in areas of the Balkans where NATO used them to blast Serb tanks.

The United Nations' Environmental Program (UNEP) sent a mission to Kosovo earlier this month as the storm broke in Europe over reports that foreign troops who served in the Balkans and the Gulf over the past decade may have been exposed to contaminated sites that could cause cancer.

The 14 experts collected 340 samples of soil, water and vegetation, conducted smear tests on buildings and destroyed Yugoslav army vehicles, and found remnants of DU ammunition at eight of the 11 sites they visited.

UNEP is working with the World Health Organization and the International Agency for Research on Cancer to try to determine exactly what risks soldiers and civilians run from DU weapons.

UNEP had asked the Spiez lab to check the samples for enriched uranium, and it found traces of uranium 236, created during processing in nuclear power plants.

But UNEP has said the traces were so small that the weapons containing it would have been no more dangerous than purely DU arms.

Per quanto riguarda l'atteggiamento estremamente ambiguo dell'UNEP, vedere: UN Covers Up in: DU Watch To Government Standards