A Step back from Sensationalizm :
What is DU and How is it produced ?
WHO:Depleted uranium: sources, exposure and health effects
Uranium is a naturally occurring, ubiquitous, heavy metal found in various chemical forms in all soils, rocks, seas and oceans. It is also present
in drinking water and food. On average, approximately 90 μg (micrograms) of uranium exist in the human body from normal intakes of water, food
and air; approximately 66% is found in the skeleton, 16% in the liver, 8% in the
kidneys and 10% in other tissues. Natural uranium consists of a mixture of three radioactive isotopes which are identified by the mass numbers
238U(99.27% by mass)[natural Uranium,low radiation], 235U(0.72%)[highly radioactive component] and 234U(0.0054%)[highly radioactive].
235U content is enriched from 0.72% to about 3%. The uranium remaining after removal of the enriched fraction is referred to as depleted uranium.
Depleted uranium typically contains about 99.8% 238U, 0.2% 235U and 0.0006% 234U by mass.
For the same mass, depleted uranium has about 60% of the radioactivity of uranium.
Depleted uranium may also result from the reprocessing of spent nuclear reactor fuel. Under these conditions another uranium isotope, 236U may be
present together with very small amounts of the transuranic elements plutonium, americium and neptunium and the fission product technetium-99. The
increase in the radiation dose from the trace amounts of these additional elements is less than 1%. This is insignificant with respect to both
chemical and radiological toxicity.
From other sources:
Uranium and Depleted Uranium
Every tonne of natural uranium produced and enriched for use in a nuclear reactor gives about 130 kg of enriched fuel (3.5% or more U-235). The
balance is depleted uranium (U-238, with 0.25-0.30% U-235). This major portion has been depleted in its fissile U-235 isotope by the enrichment
process. It is commonly known as DU.
DU is stored either as UF6 or it is de-converted back to U3O8, which is more benign chemically and thus more suited for long-term storage. It is also
less toxic. Every year over 50,000 tonnes of depleted uranium joins already substantial stockpiles in USA, Europe and Russia. World stock is about 1.2
Lets learn more of its radioactivity:
Ask The Experts
U238 in and of itself is not very fissile. When bombarded by neutrons released by U235 fission, it absorbs neutrons to become Pu239--
Plutonium's primary radioactive decay product is alpha rays. Alpha radiation cannot penetrate a sheet of paper, and human skin is more than enough
protection against it. If ingested, breathed in, or if plutonium gets into the blood stream through a wound, then the alpha radiation can cause
damage to DNA and increases an individual's chances of acquiring cancer.
Depleted Uranium is 40% less radioactive than natural uranium and, like plutonium, emits primarily alpha radiation
Lets look at the ways by which people can get exposed to DU :
WHO FactSheet on DU
- Under most circumstances, use of DU will make a negligible contribution to the overall natural background levels of uranium in the
environment. Probably the greatest potential for DU exposure will follow conflict where DU munitions are used.
- A recent United Nations Environment Programme (UNEP) report giving field measurements taken around selected impact sites in Kosovo (Federal
Republic of Yugoslavia) indicates that contamination by DU in the environment was localized to a few tens of metres around impact sites. Contamination
by DU dusts of local vegetation and water supplies was found to be extremely low. Thus, the probability of significant exposure to local
populations was considered to be very low.
- A UN expert team reported in November 2002 that they found traces of DU in three locations among 14 sites investigated in Bosnia following NATO
airstrikes in 1995. A full report is expected to be published by UNEP in March 2003.
- Levels of DU may exceed background levels of uranium close to DU contaminating events. Over the days and years following such an event, the
contamination normally becomes dispersed into the wider natural environment by wind and rain. People living or working in affected areas may inhale
contaminated dusts or consume contaminated food and drinking water.
- People near an aircraft crash may be exposed to DU dusts if counterweights are exposed to prolonged intense heat. Significant exposure would be
rare, as large masses of DU counterweights are unlikely to ignite and would oxidize only slowly. Exposures of clean-up and emergency workers to DU
following aircraft accidents are possible, but normal occupational protection measures would prevent any significant exposure.
How long does this DU absorbed stay in the body ?
WHO:Depleted uranium: sources, exposure and health effects
Most (>95%) uranium entering the body is not absorbed, but is eliminated via the faeces. Of the uranium that is absorbed into the blood,
approximately 67% will be filtered by the kidney and excreted in the urine in 24 hours.
Typically between 0.2 and 2% of the uranium in food and water is absorbed by the gastrointestinal tract. Soluble uranium compounds are more readily
absorbed than those which are insoluble.
What about the other effects of DU ??
Uranium and Depleted Uranium
Like most radionuclides, it[DU] is not known as a carcinogen, or to cause birth defects (from effects in utero) or to cause genetic mutations.
Radiation from DU munitions depends on how long the uranium has been separated chemically from its decay products. If thorium-234 and protactinium-234
has built up through decay of U-238, these will give rise to some beta emissions. On this basis, DU is "weakly radioactive" with an activity of
39 kBq/g quoted (15 kBq/g if pure, compared with 25 kBq/g for pure natural uranium).
And what of the DU effects in Kosovo and GWI ?
In 2001 the UN Environment Program examined the effects of nine tonnes of DU munitions having been used in Kosovo, checking the sites targeted by
it. UNEP found no widespread contamination, no sign of contamination in water of the food chain and no correlation with reported ill-health
in NATO peacekeepers. A two-year study by Sandia National Laboratories in USA reported in 2005 that consistent with earlier studies, reports of
serious health risks from DU exposure during the 1991 Gulf War are not supported by medical statistics or by analysis.
More resources: Austalasian Radiation Protection Society
National Radiation Protection Board(UK)
Lets look at Natural Sources Of Radiation too:
Source : Radioactivity in Nature- ISU
IS DU harmfull? Definitely, but it is just as harmfull as any other battlefield weapon/explosive that is used in war by a military.
Suppose the military were to use a conventional bomb it would also release toxic gasses which if inhaled will damage the lungs, many explosives leave
harmfull compunds after combustion that if ingested could be lethal etc. Reckless handling of any type of weapon can be dangerous to human health, DU
is no different. It needs to handled with due caution and the level of awareness to its effects, just the same as the effects of inhaling lot of
sulphor di-oxide, NO3, phosphor dust etc. They are all harmfull and can be lethal in large amounts.
Who is to blame?
Is it justified to blame DU for childern playing in smoking ruins or DU sharpnel piercing soldiers ? The answer is no. A war zone will always be
littered with dangerous munitions and compounds if DU is used or not. IF not DU kids will be exposed to other compounds.
Can we blame the people who make DU, i.e nuclear plants? There are vital to our way of life because of the amount of energy they supply. Then can we
blame the people who make these weapons or the people who use these weapons? The makers will always make them regardless when there is a demand, a
demand that is created by the people who use these weapons, i.e soldiers. These soldiers need weapons. We can give them the same old weapons that the
rest of the world is using and watch a bloodbath of our fellow countrymen and women as they fight agonizing wars of attrition ala Vietnam. Or we can
give them the weapons they need to do their job as quickly and effeciently as possible so that they can sweiftly cripple our enemies ability to wage
war thereby saving lives of our soldiers. Can we deny them this ability if has the potential to save lives and expedite war ? NO.
If we can put the blame on anything it is 'IGNORANCE'.
Ignorance of our soldiers in dealing with DU munitions and in operating DU armoured vehicles. Ignorance in the stoaring and transport of DU munitions.
Ignorance amongst the civilians about the dangerous of DU. Ignorance amogst ourselves about what really is DU and its effects and also ignorance
amongst the medical/quasi-scientific bodies in understanding DU.
DENY IGNORANCE !
*edit to add links and correct boldness errors
Other links that might be interesting:
Effects of Radiation on the Human Body
WHO documents on DU
[edit on 28-2-2006 by IAF101]