They were told depleted uranium was not hazardous. Now, 23 years after a US arms plant closed, workers and residents have cancer - and experts say their suffering shows the use of such weapons may be a war crime.

(Colonie, New York) - It is 50 years since Tony Ciarfello and his friends used the yard of a depleted uranium weapons factory as their playground in Colonie, a suburb of Albany in upstate New York state. ‘There wasn’t no fence at the back of the plant,’ remembers Ciarfello. ‘Inside was a big open ground and nobody would chase us away. We used to play baseball and hang by the stream running through it. We even used to fish in it - though we noticed the fish had big pink lumps on them.’

Today there are lumps on Ciarfello’s chest - strange, round tumors that protrude about an inch. ‘No one seems to know what they are,’ he says. ‘I’ve also had a brain aneurysm caused by a suspected tumor. I’m constantly fatigued and for years I’ve had terrible pains, deep inside my leg bones. I fall over without warning and I’ve got a heart condition.’ Ciarfello’s illnesses have rendered him unable to work for years. Aged 57 and a father of five, he looks much older.

The US federal government and the firm that ran the factory, National Lead (NL) Industries, have been assuring former workers and residents around the 18-acre site for decades that, although it is true that the plant used to produce unacceptable levels of radioactive pollution, it was not a serious health hazard.

Now, in a development with potentially devastating implications not only for Colonie but also for the future use of some of the West’s most powerful weapon systems, that claim is being challenged. In a paper to be published in the next issue of the scientific journal Science of the Total Environment, a team led by Professor Randall Parrish of Leicester University reports the results of a three-year study of Colonie, funded by Britain’s Ministry of Defense.

Parrish’s team has found that DU contamination, which remains radioactive for millions of years, is in effect impossible to eradicate, not only from the environment but also from the bodies of humans. Twenty-three years after production ceased they tested the urine of five former workers. All are still contaminated with DU. So were 20 per cent of people tested who had spent at least 10 years living near the factory when it was still working, including Ciarfello.

The small sample size precludes the drawing of statistical conclusions, the journal paper says. But to find DU at all after so long a period is ’significant, since no previous study has documented evidence of DU exposure more than 20 years prior… [this] indicates that the body burden of uranium must still be significant, whether retained in lungs, lymphatic system, kidneys or bone’. The team is now testing more individuals.

In 1984, having bought the factory from NL for $10 in a deal that meant the firm was exempted from having to pay for its clean-up, the federal government began a massive decommissioning project, supervised by the Army Corps of Engineers. The clean-up did not finish until summer 2007, having cost some $190m. Contractors demolished the buildings and removed more than 150,000 tons of soil and other contaminated detritus, digging down to depths of up to 40ft and trucking it 2,000 miles by rail to underground radioactive waste sites in the Rockies. All that is now left of the NL plant is a huge, undulating field, ringed by razor wire.