User:Nrcprm2026/DU health considerations

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Main article: Depleted uranium

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[edit] Health considerations

The health effects of DU are determined by factors such as the extent of the exposure and whether it was internal or external. Three main pathways exist by which internalization of uranium may occur: inhalation, ingestion, and embedded fragments or shrapnel contamination. Properties such as phase (e.g. particulate or gaseous), oxidation state (e.g. metallic or ceramic), and the solubility of uranium and its compounds influence their absorption, distribution, translocation, elimination and the resulting toxicity. For example, metallic uranium is relatively non-toxic compared to hexavalent uranium(VI) compounds such as uranyl nitrate.[1]

[edit] Chemical and radiological hazards

The chemical toxicity of uranium salts is about a million times greater than its radiological toxicity.[2] Uranium is pyrophoric when finely divided. It will corrode under the influence of air and water producing insoluble uranium(IV) and soluble uranium(VI) salts. Soluble uranium salts are toxic. Uranium accumulates in several organs, such as the liver, spleen, and kidneys. The World Health Organization has established a daily "tolerated intake" of soluble uranium salts for the general public of 0.5 µg/kg body weight (or 35 µg for a 70 kg adult.)

The radiological dangers of pure depleted uranium are 60% lower than those of naturally-occurring uranium due to the removal of the more radioactive isotopes, as well as due to its long half-life of 4.5 billion years. Depleted uranium differs from natural uranium in its isotopic composition, but its biochemistry is for the most part the same. Its radiological hazards are dependent on the purity of the uranium, and there has been some concern that depleted uranium produced as a by-product of nuclear reprocessing may be contaminated with more dangerous isotopes: this should not be a concern for depleted uranium produced as tailings from initial uranium enrichment. However, when alpha emitting radionuclides are taken into the body they become the most serious of all types of radiation hazards.[3]

[edit] Birth defects and other effects

Graph showing the rate per 1,000 births of congenital malformations observed at Basra University Hospital, Iraq, as reported by I. Al-Sadoon, et al., writing in the Medical Journal of Basrah University, (see Table 1 here). This version from data by same author(s) in Wilcock, A.R., ed. (2004) "Uranium in the Wind" (Ontario: Pandora Press.)
Graph showing the rate per 1,000 births of congenital malformations observed at Basra University Hospital, Iraq, as reported by I. Al-Sadoon, et al., writing in the Medical Journal of Basrah University, (see Table 1 here). This version from data by same author(s) in Wilcock, A.R., ed. (2004) "Uranium in the Wind" (Ontario: Pandora Press.)

Children of British soldiers who fought in wars in which depleted uranium ammunition was used are at greater risk of suffering genetic diseases such as congenital malformations, commonly called "birth defects," passed on by their fathers. Veterans of the conflicts in the Gulf, Bosnia and Kosovo have been found to have up to 14 times the usual level of chromosome abnormalities in their genes.[4]

Early scientific studies usually found no link between depleted uranium and cancer, and sometimes found no link with increases in the rate of birth defects, but newer studies have and offered explanation of birth defect links. There is no direct proof that uranium causes birth defects in humans, but it induces them in several other species of mammals, and human epidemiological evidence is consistent with increased risk of birth defects in the offspring of persons exposed to DU.[5] Environmental groups and others have expressed concern about the health effects of depleted uranium,[6] and there is significant debate over the matter. Some people have raised concerns about the use of this material, particularly in munitions, because of its proven mutagenicity,[7] teratogenicity,[8][9] in animals, and neurotoxicity,[10][11][12][13] and its suspected carcinogenic potential, because it remains radioactive for an exceedingly long time with a half-life of 4.5 billion years, and because it is also toxic in a manner similar to lead and other heavy metals.

A 2001 study of 15,000 February 1991 U.S. Gulf War combat veterans and 15,000 control veterans found that the Gulf War veterans were 1.8 (fathers) to 2.8 (mothers) times more likely to have children with birth defects.[14] After examination of children's medical records two years later, the birth defect rate increased by more than 20%:

"Dr. Kang found that male Gulf War veterans reported having infants with likely birth defects at twice the rate of non-veterans. Furthermore, female Gulf War veterans were almost three times more likely to report children with birth defects than their non-Gulf counterparts. The numbers changed somewhat with medical records verification. However, Dr. Kang and his colleagues concluded that the risk of birth defects in children of deployed male veterans still was about 2.2 times that of non-deployed veterans."[15]

In a study of U.K. troops, "Overall, the risk of any malformation among pregnancies reported by men was 50% higher in Gulf War Veterans (GWV) compared with Non-GWVs."[16]

In 2001, doctors at the hospital in Kosovska Mitrovica reported that the number of patients suffering from malignant diseases increased by 200% since 1998.[17] In the same year, The World Health Organization said there has been no reported increase in cancer among the civilian population in Kosovo.[18]

By contrast, other studies have shown that DU ammunition has no measurable detrimental health effects, either in the short or long term. The International Atomic Energy Agency reported in 2003 that, "based on credible scientific evidence, there is no proven link between DU exposure and increases in human cancers or other significant health or environmental impacts," although "Like other heavy metals, DU is potentially poisonous. In sufficient amounts, if DU is ingested or inhaled it can be harmful because of its chemical toxicity. High concentration could cause kidney damage."[19]

[edit] Patterns of exposure

Approximate area and major clashes in which DU bullets and rounds were used in the Gulf War
Approximate area and major clashes in which DU bullets and rounds were used in the Gulf War

Early studies of depleted uranium aerosol exposure assumed that uranium combustion product particles would quickly settle out of the air[20] and thus could not affect populations more than a few kilometers from target areas,[21] and that such particles, if inhaled, would remain undissolved in the lung for a great length of time and thus could be detected in urine.[22] Burning uranium droplets violently produce a gaseous vapor comprising about half of the uranium in their original mass.[23] Uranium trioxide is produced when uranium burns.[24] Uranyl ion contamination in uranium oxides has been detected in the residue of DU munitions fires.[25]

DU can disperse into the air and water.[26] The most important concern is the potential for future groundwater contamination by corroding penetrators (ammunition tips made out of DU). The munition tips recovered by the United Nations Environment Programme team had already decreased in mass by 10-15% in this way. This rapid corrosion speed underlines the importance of monitoring the water quality at the DU sites on an annual basis.[27]

In October, 1992, an El Al Boeing 747-F cargo aircraft crashed in a suburb of Amsterdam. After reports of local residents and rescue workers complaining of health issues related to the release of depleted uranium used as counterbalance in the plane, authorities began an epidemiological study in 2000 of those believed to be affected by the accident. The study concluded that because exposure levels were so low, it was highly improbable that exposure to depleted uranium was the cause of the reported health complaints.[citation needed]

For further details see Actinides in the environment.

[edit] Gulf War syndrome

Main article: Gulf War syndrome

Increased rates of immune system disorders and other wide-ranging symptoms have been reported in combat veterans of the 1991 Gulf War. It has not always been clear whether these were related to Gulf War service, but combustion products from depleted uranium munitions is still being considered as a potential cause by the Research Advisory Committee on Gulf War Veterans' Illnesses, as DU was used in tank kinetic energy penetrator and machine-gun bullets on a large scale for the first time in the Gulf War.

Some experts in health physics consider it unlikely that depleted uranium has any connection with the Gulf War Syndrome, if such an illness exists at all. A two year study headed by Sandia National Laboratories' Al Marshall analyzed potential health effects associated with accidental exposure to depleted uranium during the 1991 Gulf War. Marshall's study concluded that the reports of serious health risks from DU exposure are not supported by his analysis and are not supported by veteran medical statistics. The Sandia study was not comprehensive because it considered only the radiological risks of depleted uranium exposure,[28] but not the substantial toxicological[29][30] and reproductive risks.[5]

In 2005, uranium metalworkers at a Bethlehem plant near Buffalo, New York, exposed to frequent occupational uranium inhalation risks, were found to have the same patterns of symptoms and illness as Gulf War Syndrome victims.[31][32]

[edit] Soldier complaints

American soldiers are complaining of injuries that they attribute to depleted uranium. In early 2004, the UK Pensions Appeal Tribunal Service attributed birth defect claims from a February 1991 Gulf War combat veteran to depleted uranium poisoning.[33][34]

The US and UK governments have been attempting to monitor Gulf War veteran uranium exposure using urine tests.[35] Urine assay for uranium inhalation exposure can be useful, provided that measurements are made soon after a known acute intake. The urinary excretion rate falls substantially after exposure, particularly during the first few days. If urine analysis is carried out on a routine basis not related to the pattern of intake, then the errors in the assessment of intake can be considerable.[36] Exposure to teratogens may be measured by karyotype tests such as those most often provided for biopsy and amniocentesis. Soluble and most partially-soluble uranyl compounds affect gonadal chromosomes in proportion to the extent that they affect white blood cell chromosomes.[37] Uranyl poisoning causes immune system disorders and may cause cancer.[38]

[edit] References

  1. ^ «Gmelin Handbuch der anorganischen Chemiek» 8th edition, English translation, Gmelin Handbook of Inorganic Chemistry, vol. U-A7 (1982) pp. 300-322.
  2. ^ Miller, A.C. (2002) "Depleted uranium-catalyzed oxidative DNA damage: absence of significant alpha particle decay," Journal of Inorganic Biochemistry, 91, pp. 246-252; PMID 12121782.
  3. ^ Giffin, N. (1996) "Alpha Particles," TRIUMF Radiation Protection Training Course (Canada: TRIUMF Safety Group.)
  4. ^ Fleming, N. and Townsend, M. (August 11, 2002) "Gulf veteran babies 'risk deformities'," The Observer, (London: Guardian News and Media, Ltd.)
  5. ^ a b Hindin, R. et al. (2005) "Teratogenicity of depleted uranium aerosols: A review from an epidemiological perspective," Environmental Health, vol. 4, pp. 17.
  6. ^ A.L. Kennedy (2003) "Our gift to Iraq," Guardian Unlimited, Guardian Newspapers, U.K.
  7. ^ Monleau, M., et al. (2006) "Genotoxic and Inflammatory Effects of Depleted Uranium Particles Inhaled by Rats," Toxicological Sciences 89(1):287-295; doi:10.1093/toxsci/kfj010
  8. ^ Arfsten, D.P., et al. (2001) "A review of the effects of uranium and depleted uranium exposure on reproduction and fetal development," Toxicology and industrial health 17(5-10):180-91; PMID 12539863.
  9. ^ Domingo, J.L. (2001) "Reproductive and developmental toxicity of natural and depleted uranium: a review" Reproductive Toxicology, 15, 603-609; PMID 11738513.
  10. ^ W. Briner and J. Murray (2005) "Effects of short-term and long-term depleted uranium exposure on open-field behavior and brain lipid oxidation in rats," Neurotoxicology and Teratology 27(1):135-44; PMID 15681127.
  11. ^ Monleau, M. et al. (2005) "Bioaccumulation and behavioural effects of depleted uranium in rats exposed to repeated inhalations," Neuroscience Letters, vol. 390, pp. 31-6.
  12. ^ Lestaevel, P. et al. (2005) "The brain is a target organ after acute exposure to depleted uranium" Toxicology, 212, 219-226.
  13. ^ Jiang, G.C. and Aschner, M. (2006) "Neurotoxicity of Depleted Uranium: Reasons for Increased Concern," Biological Trace Element Research, vol. 110(1), pp. 1-18; PMID 16679544.
  14. ^ Kang, H., et al.' (2001) "Pregnancy Outcomes Among U.S. Gulf War Veterans: A Population-Based Survey of 30,000 Veterans," Annals of Epidemiology, 11(7), pp. 504-511; PMID 11557183.
  15. ^ Department of Veterans Affairs (2003) "Q's & A's - New Information Regarding Birth Defects," Gulf War Review 12(1), p. 10.
  16. ^ Doyle, P., et al. (2004) "Miscarriage, stillbirth and congenital malformation in the offspring of UK veterans of the first Gulf war," International Journal of Epidemiology, 33(1), pp. 74-86; PMID 15075150.
  17. ^ Rowland, J. (January 15, 2001) "Uranium tests for Serbs," BBC News.
  18. ^ Kelly, P. (January 7, 2001) "Cancer Among NATO Troops Linked to Ammunition Used in Balkans," CNN Sunday.
  19. ^ International Atomic Energy Agency (2003-5) "Frequently Asked Questions," Features: Depleted Uranium on the IAEA News Center web site.
  20. ^ Rostker, B. (2000) "Research Report Summaries," Depleted Uranium in the Gulf (II) Environmental Exposure Report no. 2000179-2, Office of the Special Assistant for Gulf War Illnesses, Department of Defense.
  21. ^ Mitsakou, C., et al. (2003) "Modeling of the dispersion of depleted uranium aerosol," Health Physics 84(4), pp. 538-544.
  22. ^ Horan, P., et al. (2003) "The quantitative analysis of depleted uranium isotopes in British, Canadian, and U.S. Gulf War veterans," Military Medicine 167(8), pp. 620-627; PMID 12188230.
  23. ^ Carter, R.F. and K. Stewart (1970) "On the oxide fume formed by the combustion of plutonium and uranium," Inhaled Particles 2, pp. 819-38; PMID 5527739.
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  29. ^ U.S. Center for Disease Control (1999) "Toxicological Profile for Uranium" Agency for Toxic Substances and Disease Registry, Division of Toxicology (includes discussion of teratogenic and immunotoxic effects.)
  30. ^ Sutton M, Burastero SR (2004). "Uranium(VI) solubility and speciation in simulated elemental human biological fluids". Chemical Research in Toxicology 17: 1468-1480. doi:10.1021/tx049878k. 
  31. ^ Bonfatti, J.F. (December 16, 2004) "Former Marine suffered from secret uranium work at Bethlehem, fought battle," Buffalo News.
  32. ^ Lombardi, K. (June 21, 2005) "Stirring Up the Toxic Dust," The Village Voice.
  33. ^ Williams, M. (February 9, 2004) "First Award for Depleted Uranium Poisoning Claim," The Herald Online, (Edinburgh: Herald Newspapers, Ltd.)
  34. ^ Campaign Against Depleted Uranium (Spring, 2004) "MoD Forced to Pay Pension for DU Contamination," CADU News 17 (quarterly newsletter at http://www.cadu.org.uk/ .)
  35. ^ Depleted Uranium Oversight Board (2006) "Summary of DUOB Activities," on www.duob.org.uk, accessed November 16, 2006.
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  37. ^ Schröder H, Heimers A, Frentzel-Beyme R, Schott A, Hoffman W (2003). "Chromosome Aberration Analysis in Peripheral Lymphocytes of Gulf War and Balkans War Veterans". Radiation Protection Dosimetry 103: 211-219. 
  38. ^ Wan, B., et al. (2006) "In vitro immune toxicity of depleted uranium: effects on murine macrophages, CD4+ T cells, and gene expression profiles," Environmental Health Perspectives, 114(1), pp. 85-91; PMID 16393663.