Uranium munitions – "Tolerable" radiological weapons?
MAPW policy statement adopted 1 November 2003
Depleted uranium internal contamination presents a potential neurotoxic, endocrine, reproductive, nephrotoxic, and mutagenic hazard. (Military Medicine Vol.167, Aug. 2002)
RECOMMENDATIONS
MAPW recommends:
Uranium munitions – "Tolerable" radiological weapons?
MAPW policy statement adopted 1 November 2003
Depleted uranium internal contamination presents a potential neurotoxic, endocrine, reproductive, nephrotoxic, and mutagenic hazard. (Military Medicine Vol.167, Aug. 2002)
RECOMMENDATIONS
MAPW recommends:
- Medical assessment, treatment and long term monitoring of all those who have been exposed to uranium munitions in Iraq, Kosovo and any other location where uranium munitions have been used. This includes the local people in each place, Australian troops and those of other nations, and any other persons who have may have been exposed.
- Clean up of all uranium munitions debris from all situations where it has been used, to prevent further adverse health and environmental effects. This includes removing and disposing of penetrator fragments, contaminated equipment and oxide contamination.
- Prohibition of uranium munitions. Australia should exclude its troops from any alliance that uses uranium munitions and should work for an international ban on uranium munitions, and prohibit the use (including in-training) of uranium munitions in Australia.
- Termination of uranium mining and export to those countries which produce or use uranium munitions. (It should be noted that MAPW (Australia) also advocates the complete cessation of uranium mining and export for a number of reasons unrelated to uranium munitions. The use of uranium munitions strengthens the need for the cessation of uranium as a source of power generation.)
INTRODUCTION
In the months and years following the armed conflicts in the Persian Gulf (1991 and 2003) and Kosovo (1995), a large number of soldiers, UN peacekeepers, and civilians have exhibited unexpected and unexplained health problems, including excess leukaemias and other cancers, neurological disorders, birth defects, and a constellation of symptoms loosely gathered under the rubric "Gulf War Illnesses."
Depleted uranium (DU), because of its radioactivity and chemical toxicity, has been linked to these acute health effects in the press and in public forums. Some opponents of uranium weapons have categorically asserted that exposure to depleted uranium is the direct cause of these excess cancers. US and NATO officials, citing the published research on the health effects of uranium, have dismissed DU as a potential cause of the acute health effects for which it has been blamed.
WHAT IS “DEPLETED URANIUM”?
Natural uranium is composed of three isotopes: U-238 (99.3%), U-235 (0.7%), and U-234 (0.006%). These isotopes decay at different rates, expressed in scientific parlance as half-lives. A shorter half-life means more intense radiation and, in general, greater potential to damage or destroy cells. The half-life of U-238 (the time in which its radioactivity is reduced by half) is 4.5 billion years; that of U-235 is 710 million years; and that of U-234 is 250 thousand years. For comparison, the half-life of plutonium – which can be lethal in even microscopic amounts – is 24,000 years[1].
Depleted uranium is the ‘waste’-product of the uranium ‘enrichment’ process: the manufacture of uranium with a sufficient concentration of the highly radioactive U-235 to fuel (“fission”) nuclear weapons and nuclear power plants. DU, thus “depleted” of its U-235 (now containing ~0.2%) and U-234, is mostly U-238: the non-fissionable uranium residue, which still retains about 60% of the radioactivity of natural uranium.
The term “depleted uranium” is, however, misleading in that uranium-236, plutonium, americium and other transuranic elements are common contaminants, contrary to industry specifications. These extremely toxic and radioactive substances are spent nuclear fuels and other nuclear waste which enter the DU production stream at the ‘post-fission’ stage of the nuclear chain, i.e after the fuel has been through the reactor. Although they are present only in trace quantities, they significantly increase the toxicity and radioactivity of DU munitions.
WHY USE DEPLETED URANIUM?
The high density of uranium (1.7 times denser than lead) makes it attractive for such purposes as ballast in ships and aircraft, as well as for making armour-piercing weaponry.
The US Department of Energy currently possesses about 728,000 tonnes of DU. It is waste, and thus cheap, if not “free” to the military. Extensive utilisation in munitions manufacture is one effective means of “offsite” disposal.
Owing to its high density (19.1 g/cm3), uranium can double the penetration power relative to older weapons. It also has several characteristics which give it an advantage over slightly denser tungsten, which is not as abundant and very expensive. Tungsten does not ignite as easily and is 1.75 times harder, which together with a much higher melting point, makes it more difficult to work with.
Upon impact, the high kinetic energy of a uranium projectile ignites it and helps it penetrate armour: unlike other heavy metals that tend to flatten or ‘mushroom’ upon impact, uranium has the ability to ‘self-sharpen’ as material spread out by the impact ignites (being “pyrophoric”) and burns off as the munition pierces its target.
WHAT / WHEN / WHERE
The applications of armour-piercers range from the 20 mm Phalanx gun in the navy (uranium mass: ~ 180 grams), through 30 mm gun in A-10 aircraft, to 120 mm (4.5 kg uranium) and larger tank barrels. These are not merely “tipped’, but solid uranium projectiles.
Tank armour and removable armour of combat vehicles are also hardened with DU plate.
Currently, over 20 weapon systems against hard and buried targets, stocked for imminent “wars on terror”, are made of uranium and new versions are under development and testing.
During the first Persian Gulf war (1991), US and UK aircraft fired over 800,000 uranium rounds, while tank gunners fired nearly 10,000, at a total weight of over 500 tonnes of uranium.
US forces fired another 31,000 of the 30 mm uranium munitions in Bosnia (1994-5) and in Kosovo (1999).
DU usage data is unavailable for the Afghanistan war, but estimates of between 500 and 2000 tonnes have been given for the recent invasion of Iraq.
Uranium munitions have also been fired on practice ranges in many other countries (Japan, India, Puerto Rico…). Nearly thirty nations, both industrialized and poor, make and use uranium munitions and armour.
The West Australian government (which is promoting WA as a transit point for US troops and equipment) has offered the use of the Lancelin Range to the US navy for bombing practice. Jet aircraft from the USS Abraham Lincoln and Carl Vinson – reportedly employing uranium munitions – took advantage of this opportunity in January and July 2003.
PROPERTIES OF DU
During an impact with a target, between 40 and 70% of a DU penetrator can be aerosolised resulting in rapid oxidation and burning of the uranium. The remainder of the penetrator retains its initial shape, i.e. as a solid piece of uranium. The resulting uranium oxides are dispersed on the terrain or within impacted structures as a very fine dust (aerosol): about two-thirds are dark brown/black insoluble particles; the remaining third is oxygen-rich and soluble in water, with a yellow/orange colour. The dust covers the target area, is readily re-suspended, and can travel with wind for at least tens of km. In addition, fire consuming DU ammunition and DU armour also turns the metal into oxide particles. Also, DU rounds that miss their target may corrode in soil or water, producing fine material that disperses with air movements and washes away.
Uranium oxide residue includes unnatural, sharp-edged ceramic particles that pose a special hazard inside the body. About 50 – 70% of the particles in the dust can be inhaled into the lungs, i.e. less than 10 micron in size. Survivors of an attack by DU ammunition may retain DU metal and dust in wounds. They will likely have inhaled or ingested far more uranium dust than recommended limits on intake. Civilians may also inhale or ingest uranium dust or collect fragments of uranium metal.
Uranium particles will fly around DU battlefields and beyond. With a half-life of 4.5 billion years, U-238 particles contaminate practically forever.
Recent research reveals that uranium particles were still detectable through modern air sampling techniques two years after the end of the war in Kosovo,[2] and that uranium dust was widely dispersed into the environment following the explosion of DU rounds. [3]
Moreover, in two selected soil samples from Kosovo, Danesi et al[4] found hundreds of thousands of particles in a few milligrams of contaminated soil, indicating that there may be ‘hot-spots’ at different sites hit by DU rounds. Most of the particles examined had a diameter of < 5 microns and 50% of them had a diameter < 1.5 micron.
HUMANS AND DU
Clearly, there is potential for human contamination by particles of uranium oxide.
Inhaled particles of less than 2.5 microns diameter can enter deep into the lungs and may move from the lung to the lymph nodes and bone. Embedded fragments in wounds may solubilise and redistribute in brain, lymph nodes, gonads, liver, kidney, and spleen, with the highest concentrations in skeletal tissue.
Studies of uranium in rat lung show that insoluble forms of uranium are poorly transported to blood and are retained in the lung to a far greater extent than the soluble forms.[5] Human autopsies have revealed that tracheobronchial and other pulmonary related lymph nodes had unexpectedly high concentrations of retained actinides (atomic number between 90 and 103, like Pu, U and americium)[6]. The body removes insoluble uranium oxides very slowly, halving their amount in 10 to 20 years.
Researchers have calculated chronic alpha-irradiation to local lung tissue from inhaled uranium oxide particles at ten times the natural background rate, assuming a particle size of 0.5 micron in diameter. They state that larger particles would deliver higher doses.[7]
Thus inhaled insoluble (ceramic) small-sized particles of uranium deposited and concentrated in deep lung tissue may deliver considerable doses to local tissue and tracheobronchial nodes. Local doses from uranium radioactivity may then accumulate and contribute to cytogenetic damage in peripheral blood lymphocytes. [8](7)
Uranium is also a heavy metal, with the attendant chemical toxicity.
The Boeing Corporation actually addresses the above concerns in its Safety Guide (2001) for DU counterweights in aircraft and missiles, which advises:
”Most heavy metals, such as uranium, are toxic to humans depending on the amount introduced into the body. For short-term (acute) exposures, the toxicological effects are the primary concern, and acute exposures to significant amounts of uranium may result in kidney damage. “ [Section 4.1.2].
“The principal radiological hazard associated with uranium is due to high linear energy transfer of the alpha particles its radionuclides and daughters emit. A chronic exposure to these radionuclides results in an increased risk of cancer, typically in the bones, kidney, and lungs, since these are the organs where uranium is deposited.” Section 4.1.3
“Failure to control airborne contamination could result in inhalation of the contamination and spread of contamination to other areas.” Section 6.2.5
“Wear a respirator […] whenever entering areas with airborne DU dust particles." Section 12.2.3[9]
The Office of the Special Assistant for Gulf War Illnesses, which reports to the US Department of Defence, has itself stated that DU can pose a chemical toxicity and radiological hazard under specific conditions.[10] Moreover, any impurities that may have found their way into the DU munitions used in either the Gulf or the Balkans – including plutonium, actinides, and the highly radioactive manufactured isotope U-236[11] – pose unquestionably serious health threats.
DU AND PATHOGENESIS
Most of the radiation from U-238 – about 95% – is emitted as alpha particles at 4.2 Milli-electronvolt (Mev) and 4.15 Mev – high in energy but ranging only a few millimetres in the air, as well as the b-particles and g-rays from its daughter products.
One milligram of U-238 emits the equivalent of over one billion ionizing particles and rays per year. A typical respirable U-238 particle has a mass of a few nanograms (one billionth of a gram), and so may emit about a thousand particles per year, or one every few hours.
Alpha-emitters cause very high doses to local cells in the 40-micron range of their disintegration tracks. Cells will be hit again and again since the particle will continue to emit radiation: a lifetime of alpha-particle bombardment of surrounding cellular microenvironments ensues.
Even low doses of low-level radiation can cause some damage to the DNA in living cells. In recent years biologists have identified specific radiation-induced damage at the molecular level to nucleotide sequences on chromosomal DNA, including double-strand breaks, large deletions and sister chromatid exchange. Mutational events at key points such as the proto-oncogene or suppressor gene loci provide a credible mechanism for radiation-induced malignant transformation.
Evidence has emerged recently that the cell may also exhibit the phenomenon of “genomic instability”, where the progeny of an irradiated cell may unexpectedly become highly susceptible to general mutation. This may also occur in the progeny of cells close to the cell which is traversed by the radiation track but which themselves are not directly hit (‘bystander effect’).
Miller has discovered the first direct evidence that radiation from DU damages chromosomes within cultured cells. The chromosomes break, and the fragments reform in a way that results in abnormal joins. Both the breaks and the joins are commonly found in tumour cells.[12] Miller and co-workers have also demonstrated[13] in in vitro experiments that DU is able to catalyse reactions of hydrogen peroxide and ascorbate, generating oxidative DNA damage that can induce carcinogenic lesions that have been observed previously in experiments with mice.[14]
Researchers at the Bremen Institute for Prevention Research, Social Medicine and Epidemiology in Germany recently published results from tests in which they took blood samples from 16 Gulf War veterans, and counted the number of chromosomes in which broken strands of DNA had been incorrectly repaired. In veterans, these abnormalities occurred at five times the rate as in a control group of 40 healthy volunteers. [15]
Some critics have rejected such findings as being inconsistent with the risk models devised by the International Commission on Radiation Protection (IRCP). But the ICRP applies the results of studies of external acute radiation exposure (the studies of Japanese atomic bomb survivors in particular) to internal chronic exposures from point sources. By relying mainly on physical models for radiation action to support this, the ICRP does not account for the probabilistic exposures that occur at the cell level. [16]
MAPW RESPONSE
Australia has been supplying uranium (as yellowcake) to both the US and the UK for half a century, so it seems reasonable to assume that a proportion of the thousands of tonnes of uranium-235 and –238 now spread around Iraq, Afghanistan and Kosovo originated in places like Rum Jungle, Mary Kathleen, Ranger and Roxby Downs. Australians recently went to war in the name of thwarting development of weapons of mass destruction, at the same time as we facilitated the dispersal of radioactive waste all over the enemy’s countryside: the cities, suburbs, towns and villages of Iraq received hundreds of tonnes of uranium in the recent “shock and awe” campaign.
A basic principle in radiation protection is that all exposures should be justified; that is, the benefit for those exposed should exceed the risk. This is the standard for medical radiography. The military utility of uranium weapons for the users does not justify any added health risk for non-combatants, no matter how small. The precautionary principle states that in the absence of convincing proof that a substance or process is harmless, the presumption must be risk. This principle applies clearly to the use of uranium weapons.
Furthermore, uranium weapons indiscriminately contaminate the places in which they are used, and the contamination persists long after the conclusion of hostilities, adding to the radioactive and toxic burden imposed upon civilians, wildlife, and ecosystems.
From this perspective, uranium weapons should be considered a form of ecological warfare prohibited by the Geneva Conventions. [17]
The damage caused by uranium weapons cannot be contained to "legal" fields of battle; they continue to act after the conclusion of hostilities; they are inhumane because they place the health of non-combatants, including children and future generations, at risk; and they cannot be used without unduly damaging the natural environment.[18]
The fact that military authorities in both the US and NATO advise their own soldiers to take precautions when handling uranium munitions and have prepared detailed training manuals and videos to ensure troop safety,[19] while issuing blanket denials of health risks to the public, strikes us as hypocritical at the very least, and reinforces our judgment that these weapons should be withdrawn from service.
Uranium weapons (which should be labelled as “dirty bombs”, or “radiological weapons”) are only one example of the continuing ways in which militaries pollute our planet: they are emblematic of the unacceptable costs of contemporary armed conflict to civilian populations, who were the predominant casualties of war in the 20th century, and are likely to remain so in the 21st. They are on the spectrum of indiscriminate and inhumane weapons that includes landmines and biological and chemical weapons, and that, at its most devastating end, includes tens of thousands of nuclear weapons that jeopardize all life on earth.
CONCLUSION
MAPW condemns the use of depleted uranium weapons and supports the calls from the European Union, International Physicians for Prevention of Nuclear War and elsewhere for a ban on their use.
Specifically, we recommend:
- Medical assessment, treatment and long term monitoring of all those who have been exposed to uranium munitions in Iraq, Kosovo and any other location where uranium munitions have been used. This includes the local people in each place, Australian troops and those of other nations, and any other persons who have may have been exposed.
- Clean up of all uranium munitions debris from all situations where it has been used, to prevent further adverse health and environmental effects. This includes removing and disposing of penetrator fragments, contaminated equipment, and oxide contamination.
- Prohibition of uranium munitions. Australia should exclude its troops from any alliance that uses uranium munitions and should work for an international ban on uranium munitions, and prohibit the use (including in-training) of uranium munitions in Australia.
- Termination of uranium mining and export to those countries which produce or use uranium munitions. (It should be noted that MAPW (Australia) also advocates the complete cessation of uranium mining and export for a number of reasons unrelated to uranium munitions. The use of uranium munitions strengthens the need for the cessation of uranium as a source of power generation.)
REFERENCES
[1] Kathren, RL(Richland, WA:USTUR) (1996)
[2] U.N. Environment Program Geneva: UNEP. 16 January 2001.
[3] Kerekes et al, Health Physics. 80(2), 177-178 (2001)
[4] Danesi et al, J. Environ. Radiat. In press.
[5] Stradling et al. Human Toxicol.7(2), 133-139 (1988)
[6] Kathren, RL(Richland, WA:USTUR) (1996)
[7] Bramhall, Lancet 357,1532 (2001)
[8] Schroeder et al. Radiation Protection Dosimetry, 103(3), 211-219 (2003)
[9] Boeing 2001
[10] US Army. Contaminated and damaged equipment management operations (training video). 1995.
[11] UN Environment Programme. Geneva: UNEP. 16 January 2001.
[12] Miller et al, Military Medicine, vol 167, p 120
[13] Miller et al, J. Inorg. Biochem 91(1),246-252 (2002)
[14] Miller et al, Environ. Health Perspect. 106(8), 465-471 (1998)
[15] Schroeder et al. (ibid), Radiation Protection Dosimetry, vol. 103, p 211
[16] European Committee on Radiation Risk (2003)
[17] Protocol additional to the Geneva conventions of 12 August 1949, and relating to the protection of victims of international armed conflicts (Protocol I). Section IV, Article 55.
[18] Parker K. Conference statement. International conference: campaign against depleted uranium. Manchester, UK. 4-5 November 2000.
[19] US Army. Contaminated and damaged equipment management operations (training video). 1995.