Depleted uranium is a mildly radioactive substance. Depleted uranium shells are not sufficiently radioactive to be classified as a "radiological weapon". Tank crews firing the rounds are reported to receive the equivalent of a chest X-ray each day. Fresh-from-the-factory DU tank shells are normally handled with gloves, to minimise the health risk, and shielded with a thin coating. The alpha particle radiation emitted by DU travels less than an inch and can be stopped by cloth or even tissue paper. However, the health risk becomes much greater once the projectile has been fired. When the DU material burns (usually on impact; or as a dust, it can spontaneously ignite) protective shields disappear and radioactive oxides are produced that can be inhaled or ingested. Once inside the body, the toxic oxide dust that emits alpha particles that they can destroy cells in soft tissue. In addition to its radioactivity, uranium is chemically toxic, like lead, and can damage the kidneys or lungs. Children are especially vulnerable because their cells divide rapidly as they grow. In pregnant women, absorbed uranium can cross the placenta into the bloodstream of the foetus and cause child deformity or abortion.
DU began accumulating in the USA in the early 1940s while the Manhattan Project was developing the first atomic bombs. To date, more than 500 thousand tons have been produced, and it continues to accumulate. At the uranium enrichment plant in Paducah, Kentucky, and two other locations, DU is packed into metal containers and stored outdoors.
Production of DU missiles began in the 1970s and 1980s at a number of military munitions factories. The weapons are tested at several firing ranges around the country.
The US military first used DU munitions in combat during the Gulf War, firing penetrators from 120 and 105mm canons mounted on tanks. Aircraft fired them from 25 or 30mm guns. The British fired DU rounds from tanks only. During Operation Desert Storm (24 - 28 February 1991), at least 10,000 rounds of DU ammunition were fired from tanks, and at least 940 thousand were fired from aircraft. At least 40 tonnes of depleted uranium was dispersed in Iraq and Kuwait in this way, considered sufficient to cause tens of thousands of potential deaths. It may have contaminated soil and drinking water. Doctors wonder if the fatal epidemic of mysterious stomach diseases and swollen abdomens amongst Iraqi children is caused by kidney failure resulting from uranium poisoning, made worse by malnutrition and poor health conditions. UN personnel and aid workers have seen children playing with empty shells, abandoned weapons and destroyed tanks. One child was using depleted uranium shells as hand puppets. Six American vehicles struck with DU "friendly fire" were deemed to be too contaminated to take home, and were buried in Saudi Arabia. Of 16 more brought back to a purpose-built facility in South Carolina, six had to be buried in a low-level radioactive waste dump.
The Pentagon has traditionally been tight-lipped about DU. Official figures on the amount used were not released for years after the 1991 Gulf War and Bosnia conflicts, and nearly a year after the 1999 Kosovo campaign. There are no official figures for DU use in the latest war in Iraq (2003).
The NATO announcement of March 1999 that it was using such shells in Kosovo has been condemned by international human rights groups.
The science says there is some danger - not perhaps a huge danger - of these objects.... We certainly do not say that these things are safe; we say that cleanup is important.
DU is relatively harmless and a necessary part of modern warfare. Children playing with expended tank shells would have to eat and then practically suffocate on DU residue to cause harm.