SHELLS fired in the Gulf war and Kosovo were made out of material contaminated by a potentially lethal cocktail of nuclear waste, according to a book published this week.

The claim, supported by American army and government documents, suggests that the military in Kosovo and Iraq used depleted uranium (DU) shells containing traces of elements that indicate the probable presence of plutonium and other highly toxic nuclear by-products.

The allegations contained in Depleted Uranium: The Invisible War will embarrass the British and American governments, which have consistently denied DU is harmful, and enrage veterans of the Gulf and Kosovo.  Martin Messonnier, Frederick Loore and Roger Trilling, the authors of the book, are convinced that the Pentagon has misled the world with claims that its DU is safe.

Until now, the Pentagon has maintained that DU shells are safe because they contain only mildly radioactive uranium. But the authors claim the shells were made with uranium contaminated with more toxic elements.  DU was first used in the Gulf war where the dense metal proved deadly against Iraqi tanks. The American army is determined to keep the shells in its arsenal despite the fact the American navy has withdrawn them on health grounds.

The authors' claims are based on papers that have led them to three nuclear plants in Paducah, Kentucky; Portsmouth, Ohio; and Oak Ridge, Tennessee - the main makers of DU.

Last January Bill Richardson, the energy secretary, accepted after decades of denials that thousands of workers at Paducah "had been exposed to radiation and chemicals that produced cancer and early death".  Most of the victims display symptoms similar to Gulf war veterans - particularly chronic fatigue and joint pain. The authors claim the workers had been handling uranium contaminated with plutonium, which was then used to make DU.

Documents from August 1999 show that workers at Paducah had been inhaling plutonium as part of a "flawed government experiment to recycle used nuclear reactor fuel". The first sign was employees with a string of cancers in the 1980s.

In October 1999 the energy department reported that "during the process of making fuel for nuclear reactors and elements for nuclear weapons, the Paducah gaseous diffusion plant . . . created depleted uranium potentially containing neptunium and plutonium". Plutonium can cause cancer if ingested even in minute quantities. What the workers at Paducah and its sister plants were dealing with were recycled uranium stocks already contaminated during the enrichment process at other nuclear plants.

The workers, like the soldiers in Iraq and Kosovo, were not equipped to deal with these hazards. Paducah was designed to handle uranium, not plutonium, which is about 100,000 times more radioactive per gram. Last week United Nations officials investigating the effects of DU in Kosovo confirmed they had found traces of elements indicating plutonium. According to the authors, the only possible source for DU containing plutonium are Paducah, Portsmouth and Oak Ridge, which used the contaminated uranium.