The radiological impact of depleted uranium

Latest documents advocating the ban of depleted uranium. By Jerry Mazza, Online Journal, 23 July 2010, “….According to the Overview from the International Coalition to Ban Uranium Weapons,Depleted Uranium (DU) is nuclear waste. Uranium naturally occurs as three different isotopes U234, U235 and U238. Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons. This means that they behave in the same way chemically, but different isotopes release different amounts and kinds of radiation. The radioactive properties of DU, which is chiefly uranium 238, differ from those of uranium 235. Unlike U238, U235 is fissionable.This means that it U235 so unstable that firing neutrons at it can produce a self-sustaining series of nuclear reactions, releasing huge amounts of energy. This is the basis of nuclear weapons and nuclear power. However, before U235 is used, it needs to be concentrated as it only makes up a small proportion of naturally occurring uranium, around 0.7%. U238 makes up more than 99% of natural uranium and is less radioactive. After natural uranium has had most of the U235 removed from it, it is called �depleted uranium� i.e. uranium depleted in the isotope U235. Each kilo of reactor ready enriched uranium produced leaves you with about seven kilos of DU.

Depleted uranium weapons

Depleted Uranium itself is a chemically toxic and radioactive compound, which is used in armour piercing munitions because of its very high density. It is 1.7 times denser than lead, giving DU weapons increased range and penetrative power. They belong to a class of weapons called kinetic energy penetrators. The part of the weapon that is made of DU is called a penetrator: this is a long dart weighing more than four kilograms in the largest examples: it is neither a tip nor a coating. The penetrator is usually an alloy of DU and a small amount of another metal such as titanium and molybdenum. These give it extra strength and resistance to corrosion.

In addition to armour-piercing penetrators, DU is used as armour in US M1A1 and M1A2 battle tanks and in small amounts in some types of landmines (M86 PDM and ADAM), both types contain 0.101g of DU in the resin cases of the individual mines. 432 ADAM antipersonnel landmine howitzer shells were used on the Kuwaiti battlefields during the 1991 Gulf War. Both M86 PDM and ADAM mines remain in U.S. stockpiles. Patents exist for the use of a �dense metal� as ballast in large �bunker busting� bombs; such weapons have been deployed but it is unclear whether they contain DU, tungsten or a third high density substance, as their contents remain classified.

Where has DU been used and when?

Governments have often initially denied using DU because of public health concerns. It is now clear that DU was used on a large scale by the US and the UK in the Gulf War in 1991, then in Bosnia, Serbia and Kosovo, and again in the war in Iraq by the US and the UK in 2003. It is suspected that the US also used DU in Afghanistan in 2001, although both the US and UK governments have denied using it there. However, leaked transport documents suggest that US forces in Afghanistan have DU weapons. The continued use of A10 �Warthog� aircraft in support of NATO ground troops indicates that DU may be being used there.

Why is it a problem?

The DU oxide dust produced when DU munitions burn has no natural or historical analogue. This toxic and radioactive dust is composed of two oxides: one insoluble, �the other sparingly soluble. The distribution of particle sizes includes sub-micron particles that are readily inhaled into and retained by the lungs. From the lungs uranium compounds are deposited in the lymph nodes, bones, brain and testes. Hard targets hit by DU penetrators are surrounded by this dust and surveys suggest that it can travel many kilometres when re-suspended, as is likely in arid climates. The dust can then be inhaled or ingested by civilians and the military alike.

It is thought that DU is the cause of a sharp increase in the incidence rates of some cancers, such as breast cancer and lymphoma, in areas of Iraq following 1991 and 2003. It has also been implicated in a rise in birth defects from areas adjacent to the main Gulf War battlefields.

Soft target impacts, typical of aircraft strikes, tend to leave the penetrators partially intact as the vast majority miss their targets. In the Balkans more than 31,000 30mm penetrators were fired; UNEP reported that these corroding penetrators were likely to contaminate groundwater and drinking water supplies and should be removed.

While we have a reasonable idea how much DU was used in the Balkans (12,700kg) and the 1991 Gulf War (290,300kg), there is little data on the extent of its use following the 2003 invasion in Iraq. One estimate put the total at 140,000kg by early 2004; with far more being used in urban areas than in 1991. This was chiefly a product of a move towards asymmetric warfare but also an increasingly casual approach to DU�s use. The US consistently refused to release data on the locations of DU strikes to UNEP and post-conflict instability has made assessing the true extent of contamination virtually impossible.

Latest documents advocating the ban of depleted uranium