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Friday, December 18, 2009
Terror On The Tarmac
Zionist Senator Goes Ballistic
Two Jewish Senators Cause A Commotion
Air Marshals At The Ready
What Happened?
A Washington hack confronted a stewardess, caused a commotion, and delayed a fight.
A Washington hack confronted a stewardess, caused a commotion, and delayed a fight.
Chuck Schumer Threatens Stewardess
Schumer wanted passengers moved, an immediate drink, and wouldn't get off his cell phone. When told to unblock the aisle he said "Don't you know who I am".
A few minutes later, his phone rang again. "It's Harry Reid calling," Politico's source quoted Schumer as saying. "I guess health care will have to wait until we land."
Schumer wanted passengers moved, an immediate drink, and wouldn't get off his cell phone. When told to unblock the aisle he said "Don't you know who I am".
A few minutes later, his phone rang again. "It's Harry Reid calling," Politico's source quoted Schumer as saying. "I guess health care will have to wait until we land."
A Stewardess Doing Her Job
According to eye witnesses, the attendant asked both Schumer and Sen. Kirsten Gillibrand, to turn off their phones so the plane could take off. Schumer resisted, continueing with his call.. When told "no," he kept arguing, according to Politico's witness, a House Republican aide.He eventually hung up. After the attendant walked away, Schumer turned to Gillibrand and called the attendant a "bitch."
According to eye witnesses, the attendant asked both Schumer and Sen. Kirsten Gillibrand, to turn off their phones so the plane could take off. Schumer resisted, continueing with his call.. When told "no," he kept arguing, according to Politico's witness, a House Republican aide.He eventually hung up. After the attendant walked away, Schumer turned to Gillibrand and called the attendant a "bitch."
Passengers Became Angry
The flight attendant then approached Mr. Schumer and told him the entire plane was waiting for him to shut off his phone.
The flight attendant then approached Mr. Schumer and told him the entire plane was waiting for him to shut off his phone.
Schumer's Aide Covers Up
"The senator made an off-the-cuff comment under his breath that he shouldn't have made, and he regrets it," Schumer spokesman Brian Fallon said.
"The senator made an off-the-cuff comment under his breath that he shouldn't have made, and he regrets it," Schumer spokesman Brian Fallon said.
Schumer Rushes Off Jet
When Senator Schumer arrived at his destination, he was whisked off the jet, and had no time for reporters.
When Senator Schumer arrived at his destination, he was whisked off the jet, and had no time for reporters.
9. U. S. ships sand from Kuwait to Idaho
In May, an unusual shipment made its way from Kuwait to Idaho: 6,700 tons of radioactive sand. The cargo, contaminated by traces of depleted uranium from military vehicles and munitions that caught on fire during the first Gulf War, was extracted from a U.S. army base and dumped at a hazardous waste disposal site 70 miles southeast of Boise. And this isn't the first shipment, either: in years past, the dump operator, American Ecology Corp., has ferried hazardous materials from U.S. military bases overseas to sites in Idaho, Nevada, and Texas. "As you can imagine," a company spokesman explained to the Associated Press, apparently without irony, "the host countries of those bases don't want the waste in their country. FROM 2008.
Crews moving contaminated sand from ship to rail Tuesday, April 29, 2008 9:07 PM PDTBy Erik OlsonLongshoremen should finish unloading 6,700 tons of sand contaminated with depleted uranium and lead Tuesday afternoon, said Chad Hyslop, spokesman for the disposal company American Ecology.The BBC Alabama arrived at the port Saturday afternoon with the 306 containers carrying the contaminated sand from Camp Doha, a U.S. Army base in Kuwait. The sand was packaged in bags designed to transport hazardous waste.Longshoremen unloaded the containers in two shifts Sunday, then two more Monday, Hyslop said. They wore standard safety gear, and dust protection equipment and respirators were available, he said.However, no one has opted to wear the respirators, he said.“It’s gone real smooth,” Hyslop said.Half of the containers will be loaded onto 76 rail cars and transported to an American Ecology disposal site in Idaho. The other half will remain at the port until the trains return to haul them to Idaho. The containers all will be at the disposal site in Idaho within 15 to 30 days, Hyslop said.State Department of Health personnel are at the port to test radiation levels and to ensure none of the sand spills, Hyslop said. U.S. Customs agents also were on hand to inspect the cargo, he said.
Afghan is looking at did we use Depleted Uranium without tellling them
DU fired in Mid East may claim more lives than Hiroshima
Idaho Imports Radioactive Kuwaiti Waste
When a local company sells a product off shore it usually qualifies as “EXPORT” sales, but what is it when they are selling space for contaminated uranium waste that is IMPORTED?
Local media and the mainstreamers in Longview, Washington are all over a story about 6,700 tons of sand from Kuwait contaminated with depleted uranium and lead making a rail journey from Longview to Grandview, Idaho–a route that will cross both Canyon and Ada counties.
The 306 containers of contaminated sand will end up at the Grandview hazardous waste site owned by American Ecology. The sand became contaminated with low levels of depleted uranium following a fire at Camp Doha during the first Gulf War in 1991. The U.S. Army then discovered potentially hazardous levels of lead in the shipment.
Seems to us a better final resting site for this nasty stuff would be somewhere in Southern Iraq and NOT IN MY BACK YARD.
We can’t wait to hear from former Guvs Phil Batt and Cecil Andrus who spent a good portion of their terms keeping nuke waste out of Idaho or arranging to get it moved out. While the sand emits radiation, it is much lower than transuranic waste.
Here is what the on line WIKIPEDIA has to say that appears to be pertinent:“Depleted uranium munitions are controversial because of numerous unanswered questions about the long-term health effects. DU is less toxic than other heavy metals such as arsenic and mercury, and is only very weakly radioactive because of its long half life. While any radiation exposure has risks, no conclusive epidemiological data have correlated DU exposure to specific human health effects such as cancer. However, the UK government has attributed birth defect claims from a 1991 Gulf War combat veteran to DU poisoning, and studies using cultured cells and laboratory rodents continue to suggest the possibility of leukemogenic, genetic, reproductive, and neurological effects from chronic exposure. Until such issues are resolved with further research, the use of DU by the military will continue to be controversial.”
The spin docs for the U.S. government will tell us it isn’t really THAT dangerous…which begs the question: “Why not leave it in the Mideast?” No doubt someone will be able to tell us importing the radioactive junk will mean jobs for Idaho.
The 306 containers of contaminated sand will end up at the Grandview hazardous waste site owned by American Ecology. The sand became contaminated with low levels of depleted uranium following a fire at Camp Doha during the first Gulf War in 1991. The U.S. Army then discovered potentially hazardous levels of lead in the shipment.
Seems to us a better final resting site for this nasty stuff would be somewhere in Southern Iraq and NOT IN MY BACK YARD.
We can’t wait to hear from former Guvs Phil Batt and Cecil Andrus who spent a good portion of their terms keeping nuke waste out of Idaho or arranging to get it moved out. While the sand emits radiation, it is much lower than transuranic waste.
Here is what the on line WIKIPEDIA has to say that appears to be pertinent:“Depleted uranium munitions are controversial because of numerous unanswered questions about the long-term health effects. DU is less toxic than other heavy metals such as arsenic and mercury, and is only very weakly radioactive because of its long half life. While any radiation exposure has risks, no conclusive epidemiological data have correlated DU exposure to specific human health effects such as cancer. However, the UK government has attributed birth defect claims from a 1991 Gulf War combat veteran to DU poisoning, and studies using cultured cells and laboratory rodents continue to suggest the possibility of leukemogenic, genetic, reproductive, and neurological effects from chronic exposure. Until such issues are resolved with further research, the use of DU by the military will continue to be controversial.”
The spin docs for the U.S. government will tell us it isn’t really THAT dangerous…which begs the question: “Why not leave it in the Mideast?” No doubt someone will be able to tell us importing the radioactive junk will mean jobs for Idaho.
http://boiseguardian.com/2008/05/01/idaho-imports-radioactive-kuwaiti-waste/ be sure to read the comment section at end of story!
Army Again Turns to Depleted Uranium for New Weaponry
For decades, depleted uranium (DU) has been the material of choice for anti-tank projectiles — despite a series of controversies about its potential health hazards. But for the near future, at least, the U.S. military will keep on using DU. Alternatives based on tungsten haven’t panned out. Now, the Army is upgrading to a new 120mm Advanced Kinetic Energy round, and about the only thing we know for sure is that it will be made of DU. The generation after that … may be an improved version of DU called Stakalloy.
Kinetic rounds are slim metal darts fired from tanks like the MAA1 Abrams at very high velocity. The preference for DU is not based, as some conspiracy theorists would have it, on a diabolical scheme to dump nuclear waste in developing countries. It’s because in addition to its high hardness and density, it has a property called adiabatic shear banding. Essentially, DU is crumbly rather than squishy. During the process of high-speed penetration through metal armor, fragments flake off a DU projectile. This means that a DU projectile is “self-sharpening” (compared to tungsten, which tends to deform in a blunted, mushroom shape.) It also means that DU produces a pyrophoric effect, filling the vehicle hit with a lethal fireball of tiny burning particles. That too makes it more effective than tungsten.
For many years, the Pentagon has been researching alternatives to DU, most notably Darpa’s “Liquidmetal” initiative on amorphous tungsten. This is a “glassy metal” without a crystalline structure which is very hard and shows the right kind of behavior under extreme stress. However, there still appear to be difficulties with producing large amorphous-tungsten penetrators.
Darpa wasn’t able to comment on the current state of the amorphous-tungsten research effort. However, Peter Rowland, spokesman for the Army’s Armament Research, Development and Engineering Center (ARDEC) was able to give a categorical statement: Tungsten still plays second fiddle to depleted uranium.
“At present, there is no tungsten alloy or other material that provides armor penetration performance as good as DU,” he told Danger Room. “For some time, there have been efforts to continually improve the performance of tungsten alloys, in an effort to achieve performance comparable with DU. Thus far, DU remains superior.”
This is why the requirement for the new Advanced Kinetic Energy round specifies that it must be made of DU.
It should also be mentioned that the idea of tungsten being introduced as a “clean” alternative to “dirty” DU took something of a knock when it was found that military-grade tungsten alloy is highly carcinogenic in rats. A 2007 Department of Defense memo advised considering alternative materials to tungsten in munitions developments. Pure tungsten is not carcinogenic, and amorphous tungsten would be very different to existing applications, but this might be a difficult one to sell to the media.
Meanwhile, research continues into improving the performance of depleted uranium penetrators. From the earliest days of uranium processing, natural uranium was known as Tube Alloy (from “Tube Alloys”, a codename for the Manhattan Project), while enriched uranium was Oralloy (”Oak Ridge Alloy”) and the depleted remnant was known as Staballoy.
Staballoys containing DU with a small admixture of titanium (from 0.75 percent to 3.5 percent) have been the basis of anti-tank rounds for decades. However, now researchers are experimenting with a new version, known as Stakalloy, which combines uranium with niobium and vanadium. This is said to have improved hardness and ballistic properties compared to traditional uranium-titanium Staballoys.
In 2007, the Army requested the processing of “U-V-X Alloy Ingots,” described in the solicitation as Stakalloy. The document noted that “previous development work over the last few years at Aerojet for the Army Research Laboratory (ARL) has produced new alloys with interesting properties and test prototypes for ballistic evaluation at ARL.” The idea was to find the best method of turning the ingots into “full-scale kinetic-energy penetrators.” (A two-stage quench process is suggested to prevent cracking.)
A detailed description of the new Stakalloy can be found in the patent for it. Stakalloy, incidentally, is named after its inventor, Dr Michael Staker.
Peter Rowland stated that the Stakalloy was not being considered for the new Advanced Kinetic Energy round, but left the future wide open. ”There is no way of predicting whether the performance of tungsten alloys or some other alternative material will ever approach that of DU, or if the penetration performance of DU itself can be further improved,” he said.
It’s possible that a viable alternative to depleted uranium will emerge in the next few years. But — at least from an engineering perspective — the advantage is all with DU. Whether it remains politically acceptable is another matter.
Kinetic rounds are slim metal darts fired from tanks like the MAA1 Abrams at very high velocity. The preference for DU is not based, as some conspiracy theorists would have it, on a diabolical scheme to dump nuclear waste in developing countries. It’s because in addition to its high hardness and density, it has a property called adiabatic shear banding. Essentially, DU is crumbly rather than squishy. During the process of high-speed penetration through metal armor, fragments flake off a DU projectile. This means that a DU projectile is “self-sharpening” (compared to tungsten, which tends to deform in a blunted, mushroom shape.) It also means that DU produces a pyrophoric effect, filling the vehicle hit with a lethal fireball of tiny burning particles. That too makes it more effective than tungsten.
For many years, the Pentagon has been researching alternatives to DU, most notably Darpa’s “Liquidmetal” initiative on amorphous tungsten. This is a “glassy metal” without a crystalline structure which is very hard and shows the right kind of behavior under extreme stress. However, there still appear to be difficulties with producing large amorphous-tungsten penetrators.
Darpa wasn’t able to comment on the current state of the amorphous-tungsten research effort. However, Peter Rowland, spokesman for the Army’s Armament Research, Development and Engineering Center (ARDEC) was able to give a categorical statement: Tungsten still plays second fiddle to depleted uranium.
“At present, there is no tungsten alloy or other material that provides armor penetration performance as good as DU,” he told Danger Room. “For some time, there have been efforts to continually improve the performance of tungsten alloys, in an effort to achieve performance comparable with DU. Thus far, DU remains superior.”
This is why the requirement for the new Advanced Kinetic Energy round specifies that it must be made of DU.
It should also be mentioned that the idea of tungsten being introduced as a “clean” alternative to “dirty” DU took something of a knock when it was found that military-grade tungsten alloy is highly carcinogenic in rats. A 2007 Department of Defense memo advised considering alternative materials to tungsten in munitions developments. Pure tungsten is not carcinogenic, and amorphous tungsten would be very different to existing applications, but this might be a difficult one to sell to the media.
Meanwhile, research continues into improving the performance of depleted uranium penetrators. From the earliest days of uranium processing, natural uranium was known as Tube Alloy (from “Tube Alloys”, a codename for the Manhattan Project), while enriched uranium was Oralloy (”Oak Ridge Alloy”) and the depleted remnant was known as Staballoy.
Staballoys containing DU with a small admixture of titanium (from 0.75 percent to 3.5 percent) have been the basis of anti-tank rounds for decades. However, now researchers are experimenting with a new version, known as Stakalloy, which combines uranium with niobium and vanadium. This is said to have improved hardness and ballistic properties compared to traditional uranium-titanium Staballoys.
In 2007, the Army requested the processing of “U-V-X Alloy Ingots,” described in the solicitation as Stakalloy. The document noted that “previous development work over the last few years at Aerojet for the Army Research Laboratory (ARL) has produced new alloys with interesting properties and test prototypes for ballistic evaluation at ARL.” The idea was to find the best method of turning the ingots into “full-scale kinetic-energy penetrators.” (A two-stage quench process is suggested to prevent cracking.)
A detailed description of the new Stakalloy can be found in the patent for it. Stakalloy, incidentally, is named after its inventor, Dr Michael Staker.
Peter Rowland stated that the Stakalloy was not being considered for the new Advanced Kinetic Energy round, but left the future wide open. ”There is no way of predicting whether the performance of tungsten alloys or some other alternative material will ever approach that of DU, or if the penetration performance of DU itself can be further improved,” he said.
It’s possible that a viable alternative to depleted uranium will emerge in the next few years. But — at least from an engineering perspective — the advantage is all with DU. Whether it remains politically acceptable is another matter.
FROM THE WORLD HEALTH ORGANIZATION-
Fact sheet N°257 Revised January 2003
Depleted uranium
Uranium
Metallic uranium (U) is a silver-white, lustrous, dense, weakly radioactive element. It is ubiquitous throughout the natural environment, and is found in varying but small amounts in rocks, soils, water, air, plants, animals and in all human beings.
Natural uranium consists of a mixture of three radioactive isotopes which are identified by the mass numbers 238U (99.27% by mass), 235U (0.72%) and 234U (0.0054%).
On average, approximately 90 µg (micrograms) of uranium exists in the human body from normal intakes of water, food and air. About 66% is found in the skeleton, 16% in the liver, 8% in the kidneys and 10% in other tissues.
Uranium is used primarily in nuclear power plants. However, most reactors require uranium in which the 235U content is enriched from 0.72% to about 1.5-3%.
Depleted uranium
The uranium remaining after removal of the enriched fraction contains about 99.8% 238U, 0.2% 235U and 0.001% 234U by mass; this is referred to as depleted uranium or DU.
The main difference between DU and natural uranium is that the former contains at least three times less 235U than the latter.
DU, consequently, is weakly radioactive and a radiation dose from it would be about 60% of that from purified natural uranium with the same mass.
The behaviour of DU in the body is identical to that of natural uranium.
Spent uranium fuel from nuclear reactors is sometimes reprocessed in plants for natural uranium enrichment. Some reactor-created radioisotopes can consequently contaminate the reprocessing equipment and the DU. Under these conditions another uranium isotope, 236U, may be present in the DU together with very small amounts of the transuranic elements plutonium, americium and neptunium and the fission product technetium-99. However, the additional radiation dose following intake of DU into the human body from these isotopes would be less than 1%.
Applications of depleted uranium
Due to its high density, about twice that of lead, the main civilian uses of DU include counterweights in aircraft, radiation shields in medical radiation therapy machines and containers for the transport of radioactive materials. The military uses DU for defensive armour plate.
DU is used in armour penetrating military ordnance because of its high density, and also because DU can ignite on impact if the temperature exceeds 600°C.
Exposure to uranium and depleted uranium
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.
Intake of depleted uranium
Average annual intakes of uranium by adults are estimated to be about 0.5mg (500 μg) from ingestion of food and water and 0.6 μg from breathing air.
Ingestion of small amounts of DU contaminated soil by small children may occur while playing.
Contact exposure of DU through the skin is normally very low and unimportant.
Intake from wound contamination or embedded fragments in skin tissues may allow DU to enter the systemic circulation.
Absorption of depleted uranium
About 98% of uranium entering the body via ingestion is not absorbed, but is eliminated via the faeces. Typical gut absorption rates for uranium in food and water are about 2% for soluble and about 0.2% for insoluble uranium compounds.
The fraction of uranium absorbed into the blood is generally greater following inhalation than following ingestion of the same chemical form. The fraction will also depend on the particle size distribution. For some soluble forms, more than 20% of the inhaled material could be absorbed into blood.
Of the uranium that is absorbed into the blood, approximately 70% will be filtered by the kidney and excreted in the urine within 24 hours; this amount increases to 90% within a few days.
Potential health effects of exposure to depleted uranium
In the kidneys, the proximal tubules (the main filtering component of the kidney) are considered to be the main site of potential damage from chemical toxicity of uranium. There is limited information from human studies indicating that the severity of effects on kidney function and the time taken for renal function to return to normal both increase with the level of uranium exposure.
In a number of studies on uranium miners, an increased risk of lung cancer was demonstrated, but this has been attributed to exposure from radon decay products. Lung tissue damage is possible leading to a risk of lung cancer that increases with increasing radiation dose. However, because DU is only weakly radioactive, very large amounts of dust (on the order of grams) would have to be inhaled for the additional risk of lung cancer to be detectable in an exposed group. Risks for other radiation-induced cancers, including leukaemia, are considered to be very much lower than for lung cancer.
Erythema (superficial inflammation of the skin) or other effects on the skin are unlikely to occur even if DU is held against the skin for long periods (weeks).
No consistent or confirmed adverse chemical effects of uranium have been reported for the skeleton or liver.
No reproductive or developmental effects have been reported in humans.
Although uranium released from embedded fragments may accumulate in the central nervous system (CNS) tissue, and some animal and human studies are suggestive of effects on CNS function, it is difficult to draw firm conclusions from the few studies reported.
Maximum radiation exposure limits and their limited application to uranium and depleted uranium
The International Basic Safety Standards, agreed by all applicable UN agencies in 1996, provide for radiation dose limits above normal background exposure levels.
The general public should not receive a dose of more than 1 millisievert (mSv) in a year. In special circumstances, an effective dose of up to 5 mSv in a single year is permitted provided that the average dose over five consecutive years does not exceed 1 mSv per year. An equivalent dose to the skin should not exceed 50 mSv in a year.
Occupational exposure should not exceed an effective dose of 20 mSv per year averaged over five consecutive years or an effective dose of 50 mSv in any single year. An equivalent dose to the extremities (hands and feet) or the skin should not surpass 500 mSv in a year.
In case of uranium or DU intake, the radiation dose limits are applied to inhaled insoluble uranium-compounds only. For all other exposure pathways and the soluble uranium-compounds, chemical toxicity is the factor that limits exposure.
Guidance on exposure based on chemical toxicity of uranium
WHO has guidelines for determining the values of health-based exposure limits or tolerable intakes for chemical substances. The tolerable intakes given below are applicable to long-term exposure of the general public (as opposed to workers). For single and short-term exposures, higher exposure levels may be tolerated without adverse effects.
The general public's intake via inhalation or ingestion of soluble DU compounds should be based on a tolerable intake value of 0.5 µg per kg of body weight per day. This leads to an air concentration of 1 µg/m3 for inhalation, and about 11 mg/y for ingestion by the average adult.
Insoluble uranium compounds with very low absorption rate are markedly less toxic to the kidney, and a tolerable intake via ingestion of 5 µg per kg of body weight per day is applicable.
When the solubility characteristics of the uranium compounds are not known, which is often the case in exposure to DU, it would be prudent to apply 0.5 µg per kg of body weight per day for ingestion.
Monitoring and treatment of exposed individuals
For the general population, neither civilian nor military use of DU is likely to produce exposures to DU significantly above normal background levels of uranium. Therefore, individual exposure assessments for DU will normally not be required. Exposure assessments based on environmental measurements may, however, be needed for public information and reassurance.
When an individual is suspected of being exposed to DU at a level significantly above the normal background level, an assessment of DU exposure may be required. This is best achieved by analysis of daily urine excretion. Urine analysis can provide useful information for the prognosis of kidney pathology from uranium or DU. The proportion of DU in the urine is determined from the 235U/238U ratio, obtained using sensitive mass spectrometric techniques.
Faecal measurement can also give useful information on DU intake. However, faecal excretion of natural uranium from the diet is considerable (on average 500 μg per day, but very variable) and this needs to be taken into account.
External radiation measurements over the chest, using radiation monitors for determining the amount of DU in the lungs, require special facilities. This technique can measure about 10 milligrams of DU in the lungs, and (except for souble compounds) can be useful soon after exposure.
There are no specific means to decrease the absorption of uranium from the gastrointestinal tract or lungs. Following severe internal contamination, treatment in special hospitals consists of the slow intravenous transfusion of isotonic 1.4 % sodium bicarbonate to increase excretion of uranium. DU levels in the human, however, are not expected to reach a value that would justify intravenous treatment any more than dialysis.
Recommendations
Following conflict, levels of DU contamination in food and drinking water might be detected in affected areas even after a few years. This should be monitored where it is considered there is a reasonable possibility of significant quantities of DU entering the ground water or food chain.
Where justified and possible, clean-up operations in impact zones should be undertaken if there are substantial numbers of radioactive projectiles remaining and where qualified experts deem contamination levels to be unacceptable. If high concentrations of DU dust or metal fragments are present, then areas may need to be cordoned off until removal can be accomplished. Such impact sites are likely to contain a variety of hazardous materials, in particular unexploded ordnance. Due consideration needs to be given to all hazards, and the potential hazard from DU kept in perspective.
Small children could receive greater exposure to DU when playing in or near DU impact sites. Their typical hand-to-mouth activity could lead to high DU ingestion from contaminated soil. Necessary preventative measures should be taken.
Disposal of DU should follow appropriate national or international recommendations.
RELATED LINKS- Depleted UraniumProvides a summary of the scientific literature on uranium and depleted uranium. - WHO guidance on exposure to depleted uranium [pdf 394kb]Provides information on medical treatment from excessive DU exposure and advice for programme administrators sending personnel to DU contaminated areas. - Uranium
Depleted uranium
Uranium
Metallic uranium (U) is a silver-white, lustrous, dense, weakly radioactive element. It is ubiquitous throughout the natural environment, and is found in varying but small amounts in rocks, soils, water, air, plants, animals and in all human beings.
Natural uranium consists of a mixture of three radioactive isotopes which are identified by the mass numbers 238U (99.27% by mass), 235U (0.72%) and 234U (0.0054%).
On average, approximately 90 µg (micrograms) of uranium exists in the human body from normal intakes of water, food and air. About 66% is found in the skeleton, 16% in the liver, 8% in the kidneys and 10% in other tissues.
Uranium is used primarily in nuclear power plants. However, most reactors require uranium in which the 235U content is enriched from 0.72% to about 1.5-3%.
Depleted uranium
The uranium remaining after removal of the enriched fraction contains about 99.8% 238U, 0.2% 235U and 0.001% 234U by mass; this is referred to as depleted uranium or DU.
The main difference between DU and natural uranium is that the former contains at least three times less 235U than the latter.
DU, consequently, is weakly radioactive and a radiation dose from it would be about 60% of that from purified natural uranium with the same mass.
The behaviour of DU in the body is identical to that of natural uranium.
Spent uranium fuel from nuclear reactors is sometimes reprocessed in plants for natural uranium enrichment. Some reactor-created radioisotopes can consequently contaminate the reprocessing equipment and the DU. Under these conditions another uranium isotope, 236U, may be present in the DU together with very small amounts of the transuranic elements plutonium, americium and neptunium and the fission product technetium-99. However, the additional radiation dose following intake of DU into the human body from these isotopes would be less than 1%.
Applications of depleted uranium
Due to its high density, about twice that of lead, the main civilian uses of DU include counterweights in aircraft, radiation shields in medical radiation therapy machines and containers for the transport of radioactive materials. The military uses DU for defensive armour plate.
DU is used in armour penetrating military ordnance because of its high density, and also because DU can ignite on impact if the temperature exceeds 600°C.
Exposure to uranium and depleted uranium
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.
Intake of depleted uranium
Average annual intakes of uranium by adults are estimated to be about 0.5mg (500 μg) from ingestion of food and water and 0.6 μg from breathing air.
Ingestion of small amounts of DU contaminated soil by small children may occur while playing.
Contact exposure of DU through the skin is normally very low and unimportant.
Intake from wound contamination or embedded fragments in skin tissues may allow DU to enter the systemic circulation.
Absorption of depleted uranium
About 98% of uranium entering the body via ingestion is not absorbed, but is eliminated via the faeces. Typical gut absorption rates for uranium in food and water are about 2% for soluble and about 0.2% for insoluble uranium compounds.
The fraction of uranium absorbed into the blood is generally greater following inhalation than following ingestion of the same chemical form. The fraction will also depend on the particle size distribution. For some soluble forms, more than 20% of the inhaled material could be absorbed into blood.
Of the uranium that is absorbed into the blood, approximately 70% will be filtered by the kidney and excreted in the urine within 24 hours; this amount increases to 90% within a few days.
Potential health effects of exposure to depleted uranium
In the kidneys, the proximal tubules (the main filtering component of the kidney) are considered to be the main site of potential damage from chemical toxicity of uranium. There is limited information from human studies indicating that the severity of effects on kidney function and the time taken for renal function to return to normal both increase with the level of uranium exposure.
In a number of studies on uranium miners, an increased risk of lung cancer was demonstrated, but this has been attributed to exposure from radon decay products. Lung tissue damage is possible leading to a risk of lung cancer that increases with increasing radiation dose. However, because DU is only weakly radioactive, very large amounts of dust (on the order of grams) would have to be inhaled for the additional risk of lung cancer to be detectable in an exposed group. Risks for other radiation-induced cancers, including leukaemia, are considered to be very much lower than for lung cancer.
Erythema (superficial inflammation of the skin) or other effects on the skin are unlikely to occur even if DU is held against the skin for long periods (weeks).
No consistent or confirmed adverse chemical effects of uranium have been reported for the skeleton or liver.
No reproductive or developmental effects have been reported in humans.
Although uranium released from embedded fragments may accumulate in the central nervous system (CNS) tissue, and some animal and human studies are suggestive of effects on CNS function, it is difficult to draw firm conclusions from the few studies reported.
Maximum radiation exposure limits and their limited application to uranium and depleted uranium
The International Basic Safety Standards, agreed by all applicable UN agencies in 1996, provide for radiation dose limits above normal background exposure levels.
The general public should not receive a dose of more than 1 millisievert (mSv) in a year. In special circumstances, an effective dose of up to 5 mSv in a single year is permitted provided that the average dose over five consecutive years does not exceed 1 mSv per year. An equivalent dose to the skin should not exceed 50 mSv in a year.
Occupational exposure should not exceed an effective dose of 20 mSv per year averaged over five consecutive years or an effective dose of 50 mSv in any single year. An equivalent dose to the extremities (hands and feet) or the skin should not surpass 500 mSv in a year.
In case of uranium or DU intake, the radiation dose limits are applied to inhaled insoluble uranium-compounds only. For all other exposure pathways and the soluble uranium-compounds, chemical toxicity is the factor that limits exposure.
Guidance on exposure based on chemical toxicity of uranium
WHO has guidelines for determining the values of health-based exposure limits or tolerable intakes for chemical substances. The tolerable intakes given below are applicable to long-term exposure of the general public (as opposed to workers). For single and short-term exposures, higher exposure levels may be tolerated without adverse effects.
The general public's intake via inhalation or ingestion of soluble DU compounds should be based on a tolerable intake value of 0.5 µg per kg of body weight per day. This leads to an air concentration of 1 µg/m3 for inhalation, and about 11 mg/y for ingestion by the average adult.
Insoluble uranium compounds with very low absorption rate are markedly less toxic to the kidney, and a tolerable intake via ingestion of 5 µg per kg of body weight per day is applicable.
When the solubility characteristics of the uranium compounds are not known, which is often the case in exposure to DU, it would be prudent to apply 0.5 µg per kg of body weight per day for ingestion.
Monitoring and treatment of exposed individuals
For the general population, neither civilian nor military use of DU is likely to produce exposures to DU significantly above normal background levels of uranium. Therefore, individual exposure assessments for DU will normally not be required. Exposure assessments based on environmental measurements may, however, be needed for public information and reassurance.
When an individual is suspected of being exposed to DU at a level significantly above the normal background level, an assessment of DU exposure may be required. This is best achieved by analysis of daily urine excretion. Urine analysis can provide useful information for the prognosis of kidney pathology from uranium or DU. The proportion of DU in the urine is determined from the 235U/238U ratio, obtained using sensitive mass spectrometric techniques.
Faecal measurement can also give useful information on DU intake. However, faecal excretion of natural uranium from the diet is considerable (on average 500 μg per day, but very variable) and this needs to be taken into account.
External radiation measurements over the chest, using radiation monitors for determining the amount of DU in the lungs, require special facilities. This technique can measure about 10 milligrams of DU in the lungs, and (except for souble compounds) can be useful soon after exposure.
There are no specific means to decrease the absorption of uranium from the gastrointestinal tract or lungs. Following severe internal contamination, treatment in special hospitals consists of the slow intravenous transfusion of isotonic 1.4 % sodium bicarbonate to increase excretion of uranium. DU levels in the human, however, are not expected to reach a value that would justify intravenous treatment any more than dialysis.
Recommendations
Following conflict, levels of DU contamination in food and drinking water might be detected in affected areas even after a few years. This should be monitored where it is considered there is a reasonable possibility of significant quantities of DU entering the ground water or food chain.
Where justified and possible, clean-up operations in impact zones should be undertaken if there are substantial numbers of radioactive projectiles remaining and where qualified experts deem contamination levels to be unacceptable. If high concentrations of DU dust or metal fragments are present, then areas may need to be cordoned off until removal can be accomplished. Such impact sites are likely to contain a variety of hazardous materials, in particular unexploded ordnance. Due consideration needs to be given to all hazards, and the potential hazard from DU kept in perspective.
Small children could receive greater exposure to DU when playing in or near DU impact sites. Their typical hand-to-mouth activity could lead to high DU ingestion from contaminated soil. Necessary preventative measures should be taken.
Disposal of DU should follow appropriate national or international recommendations.
RELATED LINKS- Depleted UraniumProvides a summary of the scientific literature on uranium and depleted uranium. - WHO guidance on exposure to depleted uranium [pdf 394kb]Provides information on medical treatment from excessive DU exposure and advice for programme administrators sending personnel to DU contaminated areas. - Uranium
SO IF YOU THINK PAYING FOR THESE WARS IS EXPENSIVE-IT WILL COST 10x THIS AMOUNT TO CLEAN UP AFTER OURSELVES!
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