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Briefings and information Depleted uraniumPlease click here to download pdf version What is it?Depleted uranium (DU) is a by-product of the process that produces enriched uranium for use in atomic weapons and nuclear power plants. During this process, the fissionable isotope Uranium 235 is separated from natural Uranium. The remaining Uranium, which is 99.8% Uranium 238, has had its Uranium 235 content ‘depleted’ from 0.7% to 0.2%. Uranium 235 is much more radioactive than Uranium 238 and in its natural form the resulting depleted uranium is 60% as radioactive as naturally occurring Uranium. It has a half-life of 4.5bn years [1,2,3]. Depleted Uranium emits alpha, beta and gamma radiation. Most of this radiation, around 95%, is emitted as alpha particles that cannot penetrate the skin. Most beta radiation will not penetrate clothing and only gamma radiation will penetrate right through to deeper cell tissue [4]. Concerns arise over inhaled and ingested particles, when this tissue would be exposed to all three forms of radiation [5]. Depleted Uranium is used in munitions due to its very high density (1.7 times that of lead) that allows it to easily penetrate steel. It is also pyrophoric, the heat produced by friction as the weapon strikes steel causes it to burn (this releases fine particles of uranium oxide which can spread for miles and present the most pressing health and environmental concern) [1]. It is often given free or very cheaply to arms manufacturers by governments keen to dispose of an otherwise useless radioactive substance that would require expensive storage or disposal. In the US there are currently around 1 billion pounds of DU awaiting treatment for either disposal or possible fuel reprocessing by the Department of Energy [1]. How is it used?Depleted Uranium is known to be used in anti-tank, armour piercing munitions (30 and 120mm) and in enhanced armour for some Abrams tanks [4, 6]. Patents for guided weapons with large DU warheads have been registered since 1985 but their existence has never been confirmed. It is suspected that DU alloys may prove to be the “dense metal” used in US and allied weapons since 1989, in at least 3 different types of warhead, ammunition or submunition [7]. Conflicts used inThere are doubts over many of the conflicts DU may have been used in. Governments have often initially denied using DU. For example NATO now admits US planes fired 10,800 DU shells into Bosnia in 1995-1996 but in 1997 Lt. Cmdr. Garneau a spokesperson for the occupation forces said “at no time did NATO use DU munitions during air strikes in Bosnia” [8]. Governments have admitted however that NATO dropped 340 tons of DU in the first Gulf War in 1991 and 11 tons in the Balkans in 1999 [9,10]. It was also used in Bosnia in 1995 [8,11]. In April 2003 the UN council asserted that no DU was used in Afghanistan [3]. Britain has admitted use of 1.9 tons of DU ammunitions in Iraq so far in this conflict [12]. The US has also admitted its use but as yet has not disclosed any figures. In 2003, The Christian Science Monitor measured radiation levels in Baghdad 1,000 to 1,900 times higher than normal adding that “in this years war on Iraq, the Pentagon used its radioactive arsenal mainly in the urban centres, rather than in desert battlefields as in “91” [15]. DU munitions have been tested in Vieques, Puerto Rico [3], Torishima Island, Okinawa, Japan [14], Panama, South Korea [11], Pakistan [15], Gramat in France and at various sites in the US and Britain [6]. Medical EffectsThe effects of depleted uranium on human health are also highly contested. All sides tend to agree that the main threat to health comes from uranium oxide particles released into the atmosphere as the shell burns up. On contact with its target around 20% of the shell’s DU mass burns spontaneously and can disperse widely. The dust dispersed can be inhaled or ingested. Contamination of food and water supplies adds to the risk of ingestion. The WHO notes that this sort of contamination is sometimes a result of use of DU weapons [16]. DU has both chemical and radiological effects. As a heavy metal it is chemically toxic which poses a risk to health additional to its radioactivity. Ingested DU tends to concentrate in the bones, liver and especially the kidney. The majority of DU ingested is excreted but some may remain for life [2]. In the kidney it can increase the risk of renal damage [5, 16]. In response to a recent report by the Royal Society on health hazards of DU, one scientist wrote; “the report never quite says what is clearly stated between the lines: the levels of chemical toxicity are higher than admitted by the politicians and military, who dismiss the concept of chemical toxicity by saying the non sequitur, ‘the DU is not radioactive’” [17]. The US Department of Defense admits; “if DU enters the body it has the potential to generate significant medical consequences” [2]. While clothes and skin block the majority of radiation from DU outside the body, once inhaled or ingested, small amounts of beta and gamma radiation would be able to penetrate deep cell tissue. The IPPNW (International Physicians for the Prevention of Nuclear War) says that “even low doses of low-level radiation can cause some damage to DNA in living cells, whether enough to significantly increase the risk of cancer and other acute health effects is a matter of much debate…until now there has been no conclusive evidence but this [is not] evidence that there are no health effects”[5]. There has been a lot of publicity over cancer cases occurring soon after conflict which most sides agree are unlikely to be caused solely by DU exposure, the general period for development of cancer being between 5 and 10 years. However the IPPNW feel that this possibility cannot be ruled out [5]. There is a lot of research circulating which seems to point to a possible link between DU and cancer, the problem being that it is very difficult to prove. Epidemiological studies in post-war regions are one of the few ways DU effects on humans can really be studied, but with lack of food and clean water, and a host of other contaminants remaining after a conflict, it can be very difficult to determine causes of any findings. Dr. Alim Yacoub* et al of Basra University conducted an epidemiological study into incidences of malignancies in children under fifteen years old, in the Basra area (an area bombed with DU during the first Gulf War). They found that in the years 1990 to 1997 there was a 120% rise in the number of general malignancies, while over the 1990 to 1999 period, there was a 242% rise. Leukaemia was seen to rise 100% in the 1990 to 1999 period with a similar steeper increase in the last 2 years [2]. They noted an “abnormal increase in the incidence of cancer of the blood, lungs, digestive system, and skin” as well as “a notable increase in the incidence of congenital diseases and foetal anomalies”. This is certainly not proof of a link, as stated above it is difficult to ascertain a particular cause of any epidemiological findings. Smoke from oil fires in the area would have released carcinogens, and any possible DU effects cannot be isolated, but it is certainly food for thought. Once ingested DU can enter the bloodstream and will pass through the placenta to an unborn child, [2]. The WTO notes that children are sometimes more likely to be exposed due to hand to mouth activities [16]. Another source quoted epidemiological research showing a three-fold increase in occurrence of cancer in Bosnia between 1995 and 1997 [18]. In 2002 the Royal Society published two reports on the health hazards of DU. Although generally they concluded that risks for leukaemia and other cancers were low for ‘all conceivable battlefield situations’, they did find a doubling of the usual risk of death by lung cancer under ‘extreme circumstances’ such as ‘working for a long time in and around contaminated vehicles’. Under the same circumstances they also noted an increased risk of kidney damage due to chemical toxicity. It was found that ‘soil around impact sites of DU penetrators may be heavily contaminated…large numbers of corroding DUPs embedded in the ground may pose a long term threat if DU leeches into water’, and recommended post conflict clean ups and long term monitoring of water and milk [19]. There is also concern over embedded fragments of DU shrapnel [5]. Uranium from embedded fragments may accumulate in the central nervous system tissue and some studies suggest effects on CNS function [16]. Gulf War Syndrome is often attributed to DU, although again there is no concrete evidence for this. Most agree it is due to a variety of factors and DU may be one of these. Half of all 697,000 US soldiers involved in the 1991 war have reported serious illnesses, with 30% of these chronically ill and receiving benefits. This is very high, most are in their mid thirties and were selected for their physical fitness [15]. The UMRC (Uranium Medical Research Council) believes the toxic and radiological effects of uranium contamination may weaken the immune system, causing acute respiratory conditions like pneumonia, flu like symptoms and severe coughs or gastrointestinal illnesses. Initial symptoms are thought to be mostly neurological; headaches, dizziness, with longer-term effects including cancers, chronic fatigue and mood disturbances. Apparently the Pentagon’s own internal reports warned of kidney, lung and liver damage and increased rates of cancer. The Pentagon continues to assert there are no “known” health problems associated with DU but in training manuals require anyone within 75ft of contaminated equipment or terrain to wear respiratory and skin protection [15]. The IPPNW “urge caution” in making categorical assertions or denials about health effects until independent, peer reviewed studies have been conducted [5]. Recent Royal Society reports have been criticised for omissions and UNEP (UN Environmental Protection) reports have in the past been undermined as scientists have been refused access to sites before cleanups have taken place. While many studies to date have not found increased rates of cancer or blood disorders in even well above average exposure, the IPPNW points out these studies often do not take into account all of the new experimental data. Aerosol particles generated by DU munitions are in a very hard “ceramic” state and so are likely to be retained in the lung and its regional lymph nodes for a prolonged period, which increases the risk of cellular damage from alpha radiation [5], usually not considered. A lot of research still needs to be done. There is general concern from all sides over the possible effects of DU. The MOD is now monitoring veterans and a report on the reproductive health of UK Gulf veterans is due to be published by the Medical Research Council in February of this year. The WHO has said that “while there is no substantiated scientific evidence…the WHO is concerned about reports of increased cancers and birth abnormalities following the [first] gulf war’, and has proposed a new study into DU for which they are currently seeking funding [18]. The UNEP is due to assess DU levels in Iraq ‘when the security situation allows’[12]. ContaminantsAn additional health risk may be posed by contaminants in DU munitions. The US Department of Defense admits that “Uranium extracted…included low levels of transuranics (americanium, neptunium and plutonium), technetium-99 and uranium-236” [12], which the IPPNW considers pose “unquestionably serious health threats” as for example plutonium “can be lethal in even microscopic amounts” [5]. References1. www.iacenter.org/depleted/metal-leftbooks.htm Anna Stevens, CND intern, Jan ‘04 | img | |||||||||||||||||