Governments deny it, but many people have long suspected that depleted uranium weapons may cause cancer. It looks as if the suspicions were right.

Depleted uranium (DU) is a dense, weakly radioactive metal used in armour-piercing shells. Hundreds of tonnes of them were fired by US and UK forces in Iraq in 2003. Previous research at the US government's Sandia National Laboratories in New Mexico found that people exposed to DU dust were at little extra risk of developing cancers (New Scientist, 30 July 2005, p 5).



Now the first study of DU's effects on human lung cells suggests otherwise. Toxicologist John Wise and colleagues at the University of Southern Maine in Portland exposed cultures of human bronchial fibroblasts to particles of uranium oxide typically found in DU dust. Chromosomes in the cells mutated and the cells died, genotoxic effects that increased with the particle concentration. This may increase a person's risk of lung cancer, the team conclude (Chemical Research in Toxicology, DOI: 10.1021/tx700026r).