Effect of DU on DNA - Does it bind to the double helix?

This is a scientific question getting a lot of attention from anti-DU activists recently. Here is a small collection of links to relevant articles and studies. The first three articles are essentially the same.

Uranium’s Effect On DNA Established Media article 7 April 2006
"...Northern Arizona University biochemist Diane Stearns has established that when cells are exposed to uranium, the uranium binds to DNA and the cells acquire mutations, triggering a whole slew of protein replication errors, some of which can lead to various cancers. Stearns' research, published in the journals Mutagenesis and Molecular Carcinogenesis, confirms what many have suspected for some time - that uranium can damage DNA as a heavy metal, independently of its radioactive properties. "Essentially, if you get a heavy metal stuck on DNA, you can get a mutation," Stearns explained. While other heavy metals are known to bind to DNA, Stearns and her team were the first to identify this characteristic with uranium." Source: Northern Arizona University

Study may help slay 'Yellow Monster' Research pioneers understanding of uranium toxicity Media article 6 April 2006

When Cells Exposed To Uranium They Acquire Mutations
Media article, Medical News Today 9 April 2006

Molecular analysis of hprt mutations generated in Chinese hamster ovary EM9 cells by uranyl acetate, by hydrogen peroxide, and spontaneously
Molecular Carcinogenesis 2006 45 (1): 60-72
Research Article (Free abstract only)
Virginia H. Coryell, Diane M. Stearns * Department of Chemistry and Biochemistry, Northern Arizona University, Flagstaff, Arizona

Uranyl acetate induces hprt mutations and uranium-DNA adducts in Chinese hamster ovary EM9 cells.
Mutagenesis 2005 20(6):417-423
Research article (Free abstract only)
* Stearns DM (Department of Chemistry and Biochemistry, Northern Arizona University), * Yazzie M, * Bradley AS, * Coryell VH, * Shelley JT, * Ashby A, * Asplund CS, * Lantz RC.
Quote from abstract: "This is the first report of the formation of uranium–DNA adducts and mutations in mammalian cells after direct exposure to a depleted uranium compound. Data suggest that uranium could be chemically genotoxic and mutagenic through the formation of strand breaks and covalent U–DNA adducts. Thus the health risks for uranium exposure could go beyond those for radiation exposure."

Teratogenicity of depleted uranium aerosols: A review from an epidemiological perspective (Review)
Rita Hindin1 , Doug Brugge2 and Bindu Panikkar3
1Biostatistics and Epidemiology Concentration, University of Massachusetts School of Public Health and Health Sciences, Amherst, MA, USA 01003
2Department of Public Health and Family Medicine, Tufts University School of Medicine, 136 Harrison Ave., Boston, MA, USA 02111
3Department of Civil and Environmental Engineering, Tufts School of Engineering, 200 College Avenue, Anderson Hall, Medford, MA, USA 02155

Results: Animal studies firmly support the possibility that DU is a teratogen. While the detailed pathways by which environmental DU can be internalized and reach reproductive cells are not yet fully elucidated, again, the evidence supports plausibility. To date, human epidemiological data include case examples, disease registry records, a case-control study and prospective longitudinal studies.

Conclusion: In aggregate the human epidemiological evidence is consistent with increased risk of birth defects in offspring of persons exposed to DU.

Abstract: Depleted uranium (DU) is a by-product from the chemical enrichment of naturally occurring uranium. Natural uranium is comprised of three radioactive isotopes: (238)U, (235)U, and (234)U. This enrichment process reduces the radioactivity of DU to roughly 30% of that of natural uranium. Nonmilitary uses of DU include counterweights in airplanes, shields against radiation in medical radiotherapy units and transport of radioactive isotopes. DU has also been used during wartime in heavy tank armor, armor-piercing bullets, and missiles, due to its desirable chemical properties coupled with its decreased radioactivity. DU weapons are used unreservedly by the armed forces. Chemically and toxicologically, DU behaves similarly to natural uranium metal. Although the effects of DU on human health are not easily discerned, they may be produced by both its chemical and radiological properties. DU can be toxic to many bodily systems, as presented in this review. Most importantly, normal functioning of the kidney, brain, liver, and heart can be affected by DU exposure. Numerous other systems can also be affected by DU exposure, and these are also reviewed. Despite the prevalence of DU usage in many applications, limited data exist regarding the toxicological consequences on human health. This review focuses on the chemistry, pharmacokinetics, and toxicological effects of depleted and natural uranium on several systems in the mammalian body. A section on risk assessment concludes the review.

Abstract: The internal contamination with depleted uranium (DU) isotopes was detected in British, Canadian, and United States Gulf War veterans as late as nine years after inhalational exposure to radioactive dust in the Persian Gulf War I. DU isotopes were also identified in a Canadian veteran's autopsy samples of lung, liver, kidney, and bone. In soil samples from Kosovo, hundreds of particles, mostly less than 5 microm in size, were found in milligram quantities. Gulf War I in 1991 resulted in 350 metric tons of DU deposited in the environment and 3-6 million grams of DU aerosol released into the atmosphere. Its legacy, Gulf War disease, is a complex, progressive, incapacitating multiorgan system disorder. The symptoms include incapacitating fatigue, musculoskeletel and joint pains, headaches, neuropsychiatric disorders, affect changes, confusion, visual problems, changes of gait, loss of memory, lymphadenopathies, respiratory impairment, impotence, and urinary tract morphological and functional alterations. Current understanding of its etiology seems far from being adequate. After the Afghanistan Operation Anaconda (2002), our team studied the population of Jalalabad, Spin Gar, Tora Bora, and Kabul areas, and identified civilians with the symptoms similar to those of Gulf War syndrome. Twenty-four-hour urine samples from 8 symptomatic subjects were collected by the following criteria: 1) the onset of symptoms relative to the bombing raids; 2) physical presence in the area of the bombing; and 3) clinical manifestations. Control subjects were selected among the sympotom-free residents in non-targeted areas. All samples were analyzed for the concentration and ratio of four uranium isotopes, (234)U, (235)U, (236)U and (238)U, by using a multicollector, inductively coupled plasma ionization mass spectrometry. The first results from the Jalalabad province revealed urinary excretion of total uranium in all subjects significantly exceeding the values in the nonexposed population. The analysis of the isotopic ratios identified non-depleted uranium. Studies of specimens collected in 2002 revealed uranium concentrations up to 200 times higher in the districts of Tora Bora, Yaka Toot, Lal Mal, Makam Khan Farm, Arda Farm, Bibi Mahro, Poli Cherki, and the Kabul airport than in the control population. Uranium levels in the soil samples from the bombsites show values two to three times higher than worldwide concentration levels of 2 to 3 mg/kg and significantly higher concentrations in water than the World Health Organization maximum permissible levels. This growing body of evidence undoubtedly puts the problem of prevention and solution of the DU contamination high on the priority list.

Abstract: The purpose of this study was to determine the concentrations and precise isotopic compositions of four uranium isotopes (234U, 235U, 236U, and 238U) in urine specimens from the civilian population of Afghanistan after Allied Forces Operation Enduring Freedom. Eight male civilians from Nangarhar-Jalalabad region who presented with symptoms of fatigue, fever, musculoskeletal and neurological alterations, headaches, and respiratory impairment after inhalation of dust during the bombing raids in June 2002 had urine samples collected under controlled conditions and analyzed in duplicate for 234U, 235U, 236U, and 238U, with multicollector, inductively coupled, plasma ionization mass spectrometry. Control samples with an internal urine standard were analyzed with the same method. The mean concentration of uranium in eight samples was found to be considerably greater (275.04 ng/L; SD, 137.80 ng/L; SE, 48.72 ng/L) than what is regarded as a reference range (1-20 ng/L). The 238U/235U ratio was 137.87 +/- 0.20, which is consistent with that of natural uranium. The 234U/238U ratio for the Afghan samples was 0.000055 +/- 0.000001, also consistent with natural uranium. 236U, which usually forms a component of depleted uranium, was not detected (measured 236U/ 238U ratio, < 10(-7)). Our results demonstrate that contamination in Afghanistan with a source consistent with natural uranium has resulted in total uranium concentrations up to 100 times higher than the normal range for various geographic and environmental areas throughout the world. The cause of our findings is currently being evaluated as a part of our ongoing research.

Abstract: This paper reports physical, chemical and biological analyses of samples of dust resulting from munitions containing depleted uranium (DU) that had been live-fired and had impacted an armored target. Mass spectroscopic analysis indicated that the average atom% of 235U was 0.198 +/- 0.10, consistent with depleted uranium. Other major elements present were iron, aluminum, and silicon. About 47% of the total mass was particles with diameters <300 [mu]m, of which about 14% was <10 [mu]m. X-ray diffraction analysis indicated that the uranium was present in the sample as uranium oxides-mainly U3O7 (47%), U3O8 (44%) and UO2 (9%). Depleted uranium dust, instilled into the lungs or implanted into the muscle of rats, contained a rapidly soluble uranium component and a more slowly soluble uranium component. The fraction that underwent dissolution in 7 d declined exponentially with increasing initial burden. At the lower lung burdens tested (<15 [mu]g DU dust/lung) about 14% of the uranium appeared in urine within 7 d. At the higher lung burdens tested (~80-200 [mu]g DU dust/lung) about 5% of the DU appeared in urine within 7 d. In both cases about 50% of that total appeared in urine within the first day. DU implanted in muscle similarly showed that about half of the total excreted within 7 d appeared in the first day. At the lower muscle burdens tested (<15 [mu]g DU dust/injection site) about 9% was solubilized within 7 d. At muscle burdens >35 [mu]g DU dust/injection site about 2% appeared in urine within 7 d. Natural uranium (NU) ore dust was instilled into rat lungs for comparison. The fraction dissolving in lung showed a pattern of exponential decline with increasing initial burden similar to DU. However, the decline was less steep, with about 14% appearing in urine for lung burdens up to about 200 [mu]g NU dust/lung and 5% at lung burdens >1,100 [mu]g NU dust/lung. NU also showed both a fast and a more slowly dissolving component. At the higher lung burdens of both DU and NU that showed lowered urine excretion rates, histological evidence of kidney damage was seen. Kidney damage was not seen with the muscle burdens tested. DU dust produced kidney damage at lower lung burdens and lower urine uranium levels than NU dust, suggesting that other toxic metals in DU dust may contribute to the damage.
(C)2004Health Physics Society

The quantitative analysis of depleted uranium isotopes in British, Canadian, and U.S. Gulf War veterans.
Horan P, Dietz L, Durakovic A.
Department of Earth Sciences, Memorial University of Newfoundland, St. Johns, Canada.

The purpose of this work was to determine the concentration and ratio of uranium isotopes in allied forces Gulf War veterans. The 27 patients had their 24-hour urine samples analyzed for 234U, 235U, 236U, and 238U by mass spectrometry. The urine samples were evaporated and separated into isotopic dilution and concentration fraction by the chromatographic technique. The isotopic composition was measured by a thermal ionization mass spectrometer using a secondary electron multiplier detector and ion-counting system. The uranium blank control and SRM960 U isotopic standard were analyzed by the same procedure. Statistical analysis was done by an unpaired t test. The results confirm the presence of depleted uranium (DU) in 14 of 27 samples, with the 238U:235U ratio > 207.15. This is significantly different from natural uranium (p < 0.008) as well as from the DU shrapnel analysis, with 22.22% average value of DU fraction, and warrants further investigation.

The aim of this study was to estimate the amount of depleted uranium (DU) in the respiratory system of Allied Forces Gulf War Veterans. Mass spectrometry (thermal ionization mass spectrometry) analysis of 24-hour urinary excretion of DU isotopes in five positive (238U/235U > 191.00) and six negative (238U/235U > 138.25) veterans was utilized in the mathematical estimation of the pulmonary burden at the time of exposure. A minimum value for the biological half-life of ceramic DU oxide in the lungs was derived from the Battelle report of the minimum dissolution half-time in simulated interstitial lung fluid corresponding to 3.85 years. The average DU concentration was 3.27 x 10(-5) mg per 24 hours in DU-positive veterans and 1.46 x 10(-8) mg in DU-negative veterans. The estimated lung burden was 0.34 mg in the DU-positive and 0.00015 mg in the DU-negative veterans. Our results provide evidence that the pulmonary concentration of DU at time zero can be quantitated as late as 9 years after inhalational exposure.

Depleted uranium - the growing concern (Research Article)
Journal of Applied Toxicology Volume 22, Issue 3, Date: May/June 2002, Pages: 149-152
Aqel W. Abu-Qare, Mohamed B. Abou-Donia * Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA

Abstract Recently, several studies have reported on the health and environmental consequences of the use of depleted uranium. Depleted uranium is a heavy metal that is also radioactive. It is commonly used in missiles as a counterweight because of its very high density (1.6 times more than lead). Immediate health risks associated with exposure to depleted uranium include kidney and respiratory problems, with conditions such as kidney stones, chronic cough and severe dermatitis. Long-term risks include lung and bone cancer. Several published reports implicated exposure to depleted uranium in kidney damage, mutagenicity, cancer, inhibition of bone, neurological deficits, significant decrease in the pregnancy rate in mice and adverse effects on the reproductive and central nervous systems. Acute poisoning with depleted uranium elicited renal failure that could lead to death. The environmental consequences of its residue will be felt for thousands of years. It is inhaled and passed through the skin and eyes, transferred through the placenta into the fetus, distributed into tissues and eliminated in urine. The use of depleted uranium during the Gulf and Kosovo Wars and the crash of a Boeing airplane carrying depleted uranium in Amsterdam in 1992 were implicated in a health concern related to exposure to depleted uranium.

Wait a minute! I thought the pro-DU spokespeople always say natural uranium is a totally safe substance. So why does this study seem to clearly prove otherwise?

Uranium mining and lung cancer in Navajo men
JM Samet, DM Kutvirt, RJ Waxweiler, and CR Key
N Engl J Med 1984; 310:1481-1484, Jun 7, 1984

Abstract We performed a population-based case-control study to examine the association between uranium mining and lung cancer in Navajo men, a predominantly nonsmoking population. The 32 cases included all those occurring among Navajo men between 1969 and 1982, as ascertained by the New Mexico Tumor Registry. For each case in a Navajo man, two controls with nonrespiratory cancer were selected. Of the 32 Navajo patients, 72 per cent had been employed as uranium miners, whereas no controls had documented experience in this industry. The lower 95 per cent confidence limit for the relative risk of lung cancer associated with uranium mining was 14.4. Information on cigarette smoking was available for 21 of the 23 affected uranium miners; eight were nonsmokers and median consumption by the remainder was one to three cigarettes daily. These results demonstrate that in a rural nonsmoking population most of the lung cancer may be attributable to one hazardous occupation.

Related articles:
Cancer Factories: America's Tragic Quest for Uranium Self-Sufficiency
Sokas R. K. N Engl J Med 1994; 330:442, Feb 10, 1994 (Book review)
"...an epidemic of lung cancer among Mormon and Native American workers otherwise at very low risk."
The History of Uranium Mining and the Navajo People Doug Brugge, PhD, MS and Rob Goble, PhD

12 Years too Late? How Canadian and U.S. Defense Departments reveal veterans’ post-conflict follow-up programs are not
capable of detecting depleted uranium.
Weyman T.

A detailed and extensively referenced report by Tedd Weyman, deputy director of the Uranium Medical Research Center. It addresses claims that military and veterans agencies avoid using sensitive isotopic assays to measure DU exposure, prefering to use less sensitive assays which can be interpretted as 'natural uranium exposure.'

QUOTE: "The constructing of follow-up and screening programs that persist at refusing to conduct isotopic analyses on veterans whose medical symptoms and deployment histories suggest a high likelihood of inhalational exposure to DU is a distinct contradiction with other government policies and a slap in the face to veterans."

INVITED EDITORIAL Depleted uranium munitions—where are we now?
Brian G Spratt 2002 J. Radiol. Prot. 22 125-130 doi:10.1088/0952-4746/22/2/002 Recommended!
(Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College, St Mary's Hospital, London)
(Chair of Royal Society Working Group that produced the reports, The health hazards of depleted uranium munitions-Parts 1 & 2)

(Excerpt) Excepting lung cancer in a few soldiers who could be very heavily exposed to DU, any increases in other cancers, including lymphomas and leukaemias, are predicted to be too small to be detected, unless the intakes for large numbers of soldiers on the battlefield are very much greater than estimated, or the ICRP models greatly under-estimate the risks of inhaled particles of DU oxides. Some advisors to the veterans groups take the latter position, and argue that the alpha-particles from highly insoluble DU particles translocated to the thoracic lymph nodes are much more dangerous than implied by ICRP models [International Commission on Radiological Protection ], and that the risks of leukaemias and lymphomas are greatly under-estimated. These views are familiar to those who have followed the debate about leukaemia clusters and `hot particles' in discharges from the nuclear industry or increased leukaemias from the accident at Chernobyl. DU particles can hardly be called `hot' but large intakes of DU by a few soldiers working for protracted periods cleaning up contaminated vehicles without any respiratory protection, or survivors of struck tanks, could, under worst-case assumptions, result in large numbers of DU particles in the thoracic lymph nodes, providing doses of up to about 5 Gy over a 50 year period [1]. However, very much smaller doses are predicted for the great majority of soldiers on the battlefield and for those returning to live in the region.

(Excerpt) It is therefore unlikely from current scientific knowledge that there will be any detectable increase in any cancers, except perhaps lung cancer if small groups of soldiers were exposed to large amounts of DU. This conclusion has been difficult to accept for some veterans and their advisors, who are searching for a cause of the illnesses in the veterans (including Gulf War Syndrome), and who suggest that large numbers of cancers and birth defects are being seen, for example in Iraq, and who criticise the use of models to estimate cancer risks. Such critics of ICRP models believe that cancer incidence data rather than models should be used to produce the estimates of risks. Of course they are correct. Ideally, risks of cancers should be determined from the excess mortality in a population exposed to known levels of radiation, but this approach is very rarely possible as exposures are typically too low. Data from the atomic bombs in Hiroshima and Nagasaki provide a major source of the data that underpin ICRP models but critics argue that this type of radiation exposure is so different from the internal exposures to alpha-emitting radionuclides that result from inhalation intakes of DU, or from `hot particles' from nuclear power plants, that they invalidate the use of ICRP models for estimating risks for the latter type of exposures. Risks from internal exposures to alpha-particles have been obtained from underground miners exposed to radon, since the number of exposed miners, and the excess mortality from lung cancer, are large enough to make robust measures of risk. These direct measurements of risk from internal exposures agree rather well with those from IRCP models [5, 6]. In fact the modelling approach may over-estimate the risk to the lung.

Tests To Reveal Levels Of Depleted Uranium In Army Personnel
Science Daily — Source: University of Leicester Date: March 6, 2007

A test recently used by the UK government's Independent Depleted Uranium Oversight Board to detect exposure to UK troops by depleted uranium (DU) during the 1991 Gulf Conflict was developed by a team led by a University of Leicester geologist.

Randall Parrish, Professor of Isotope Geology, developed the test with Postdoctoral Fellow Dr Axel Gerdes, who now works at the University of Frankfurt, Germany, and his colleague Matt Horstwood at the British Geological Survey, using advanced mass spectrometry. Prof Parrish's team has tested more than 350 individuals as part of the programme, with the result that none so far tested had any demonstrable DU exposure resulting from their participation in the 1991 Gulf Conflict, though the extent of actual initial exposure of tested individuals to DU is unknown.
...
The test was designed to detect after 15 years even a modest exposure to DU, on the basis of accepted knowledge about the retention and solubility of DU in the human body. The test is applicable even to those who excrete extremely low levels of uranium in urine. Professor Parrish's and his colleagues' work, undertaken to help in the planning of the UK DU testing programme, explored the sensitivity and accuracy of urine tests to measure uranium concentrations and isotope ratios. The testing programme was set up in 2001, to investigate concerns amongst UK Service personnel from the Balkans and the 1991 Gulf War, following media coverage about Depleted Uranium. Professor Parrish commented: "Dr Gerdes and I continue to collaborate on this test, which is by far the most sensitive and accurate of all uranium isotope test for urine worldwide. It uses multiple isotopes to ascertain the extent of contamination. "Our facility has used this test in the monitoring of more than 400 UK veterans of the 1991 Gulf War, under the testing programme administered by the Depleted Uranium Oversight Board over the past two and a half years -- a testing programme that is nearly finished."

BACKGROUND: Gulf War Veterans have previously been shown to have, in the short-term, an excess risk of death from 'external' (i.e. non-disease) causes of death. This study aims to determine whether there remains an excess of non-disease-related deaths in Gulf Veterans, 13 years after deployment, and, for the first time, to determine whether there is a relationship between experiences reported in the Gulf, post-war symptoms, and subsequent mortality experience. METHODS: We conducted a cohort study with follow-up from April 1, 1991 (the end of the Gulf War) to June 30, 2004. Participants were 53 462 Gulf War Veterans and a cohort of military personnel, matched for age-group, sex, rank, service and level of fitness, who were not deployed to the Gulf. The outcome measure used was mortality as recorded on the NHS central register. RESULTS: There is no difference, 13 years after the end of the Gulf War, in the overall mortality experience of Gulf War Veterans. The excess in non-disease-related deaths previously reported is confined to the initial 7 years of follow-up [mortality rate ratio (MRR) 1.31, 95% confidence interval (CI) 1.06-1.63] rather than the more recent period (MRR 1.05, 95% CI 0.83-1.33). Overall experiences reported during Gulf deployment did not influence subsequent risk of dying, but there was non-significant increased risk of dying from a disease-related death (MRR 1.99, 95% CI 0.98-4.04) associated with reported exposure to depleted uranium and of a non-disease-related death associated with reporting handling of pesticides (MRR 2.05, 95% CI 0.91-4.61). Reporting of morbidity in the health surveys conducted was not related to future risk of death. CONCLUSION: The higher rates of non-disease-related deaths in Gulf War Veterans is not evident in the period of follow-up since 1997. Neither the excess morbidity reported in health surveys nor the experiences during deployment significantly influenced future mortality. The two non-significant associations found (reported depleted uranium exposure and disease death, reporting handling pesticides and non-disease deaths) need to be considered in the context of the number of possible associations examined and potential biases-although they are biologically plausible.

Incidence of major congenital malformations in a region of Bosnia and Herzegovina allegedly polluted with depleted uranium.
Sumanovic-Glamuzina D, Saraga-Karacic V, Roncevic Z, Milanov A, Bozic T, Boranic M.
Department of Pediatrics, Mostar University Hospital, Mostar, Bosnia and Herzegovina. dara.glamuzina@tel.net.ba

OBJECTIVES: To determine the prevalence of major congenital malformations in West Herzegovina, a part of Bosnia and Herzegovina, immediately and five years after 1991-1995 military activities, which allegedly included the use of weapons with depleted uranium. METHODS: The study included all live-born and stillborn neonates and excluded all aborted fetuses in two one-year cohorts (1995 and 2000) of neonates in the Maternity Ward of the Mostar University Hospital. Malformations were recorded according to the recommendations of the EUROCAT protocol. RESULTS: Major malformations were found in 40 (2.16%) out of 1,853 neonates in 1995 (95% confidence interval [CI], 1.49-2.82%) and in 33 (2.26%) out of 1,463 neonates five years later (95% CI, 1.50-3.01%), ie, at comparable prevalence. In both cohorts, anomalies of the musculoskeletal system were the most common, followed by anomalies of the digestive system (in 1995) and the cardiovascular system (in 2000). The prevalence of malformations and the organ systems involved were essentially comparable with those in other populations not affected by military activities. CONCLUSION: Despite alleged environmental pollution in some regions of the former Yugoslavia, which was attributed to military activities and the presence of depleted uranium (the "Balkan syndrome"), there was no significant postwar increase in the prevalence of congenital malformations.

A by-product of the uranium enrichment process, depleted uranium (DU) contains approximately 40% of the radioactivity of natural uranium yet retains all of its chemical properties. After its use in the 1991 Gulf War, public concern increased regarding its potential radiotoxicant properties. Whereas in vitro and rodent data have suggested the potential for uranium-induced carcinogenesis, human cohort studies assessing the health effects of natural and DU have failed to validate these findings. Heavy-metal nephrotoxicity has not been noted in either animal studies or Gulf War veteran cohort studies despite markedly elevated urinary uranium excretion. No significant residual environmental contamination has been found in geographical areas exposed to DU. As such, although continued surveillance of exposed cohorts and environments (particularly water sources) are recommended, current data would support the position that DU poses neither a radiological nor chemical threat.

NATO aircraft fired several tons of armor-piercing weapons made from depleted uranium at Serb military targets in Kosovo in 1999. To assess the danger, if any, of the resulting radiation to soldiers and local people, the United Nations Environment Programme dispatched teams of researchers to Kosovo in November 2000. At a radioecology conference last week in Monaco (see main text), one of those teams presented results that should calm the nerves of peacekeepers and Kosovars.

Note: This often-cited news blurb in Science is the only article dealing with depleted uranium ever published in this prestigious journal.

SUMMARY: Toxicology research should urgently appraise its performance and join mainstream biomedical science.
CONTEXT: ...effectively predict risk, as illustrated by the debate about servicemen exposed to depleted uranium from weapons during the Kosovo conflict in 1999. Although there is no...

Note: This article is one of just six mentions of depleted uranium in the prestigious journal since 2002. None of these deal with DU specifically. A search can be seen by following this link. Nature, DU search

INVITED EDITORIAL
Recent studies of the mortality and cancer morbidity experience of uranium workers and a fresh look at depleted uranium
R L Kathren 2001 J. Radiol. Prot. 21 105-107

Selected quotes: (Yes, the bias is mine.)

It is significant to note that there has never been a study, epidemiological or otherwise, that has demonstrated deleterious kidney effects in humans, although a recent Canadian study showed biomarkers, but no functional diminution, in older members of a population whose water had elevated concentrations of natural uranium [5]. And, as an aside, it is of at least passing interest to note that in the early 1900s, uranium was used therapeutically as a treatment for diabetes mellitus; there appear to have been no reports in the literature of kidney damage from this therapy.

Epidemiological investigation is subject to numerous confounders, and thus has very real and often unknown limitations in discerning low-level effects in a relatively small population group. Ferreting out possible small effects in one group as compared with another is an exercise that is fraught with potential for error, and there is often a tendency to give too much credibility to a single unreplicated finding, particularly by those in the media and other non-scientists who may have a particular axe to grind.

This is an extensive essay from Dr. Ron Kathren, a guy who really makes time to insist that uranium radiation, both natural and depleted, is probably even good for you.

The risk of birth defects among children of Persian Gulf War veterans.
Cowan DN, DeFraites RF, Gray GC, Goldenbaum MB, Wishik SM.
Walter Reed Army Institute of Research, Washington, D.C., USA.
N Engl J Med. 1997 Jun 5;336(23):1650-6

BACKGROUND: There has been suspicion that service in the Persian Gulf War affected the health of veterans adversely, and there have been claims of an increased rate of birth defects among the children of those veterans. METHODS: We evaluated the routinely collected data on all live births at 135 military hospitals in 1991, 1992, and 1993. The data base included up to eight diagnoses from the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) for each birth hospitalization, plus information on the demographic characteristics and service history of the parents. The records of over 75,000 newborns were evaluated for any birth defect (ICD-9-CM codes 740 to 759, plus neoplasms and hereditary diseases) and for birth defects defined as severe on the basis of the specific diagnoses and the criteria of the Centers for Disease Control and Prevention. RESULTS: During the study period, 33,998 infants were born to Gulf War veterans and 41,463 to non-deployed veterans at military hospitals. The overall risk of any birth defect was 7.45 percent, and the risk of severe birth defects was 1.85 percent. These rates are similar to those reported in civilian populations. In the multivariate analysis, there was no significant association for either men or women between service in the Gulf War and the risk of any birth defect or of severe birth defects in their children. CONCLUSIONS: This analysis finds no evidence of an increase in the risk of birth defects among the children of Gulf War veterans.

Note: This study does not directly address depleted uranium, only Gulf War vets in general.

Transformation of Human Osteoblast Cells to the Tumorigenic Phenotype by Depleted Uranium-Uranyl Chloride
Alexandra C. Miller, et. a. (all army researchers)

Abstract: Depleted uranium (DU) is a dense heavy metal used primarily in military applications. Although the health effects of occupational uranium exposure are well known, limited data exist regarding the long-term health effects of internalized DU in humans. We established an in vitro cellular model to study DU exposure. ... DU-uranyl chloride treatment resulted in a 9.6 (± 2.8) -fold increase in transformation frequency compared to untreated cells. In comparison, nickel sulfate resulted in a 7.1 (± 2.1) -fold increase in transformation frequency. This is the first report showing that a DU compound caused human cell transformation to the neoplastic phenotype. Although additional studies are needed to determine if protracted DU exposure produces tumors in vivo, the implication from these in vitro results is that the risk of cancer induction from internalized DU exposure may be comparable to other biologically reactive and carcinogenic heavy-metal compounds (e.g., nickel) .

And so it goes for nickel as well. This study looked at the effect of dissolved uranium and nickel salts on Petri dish cultures of human cell lines. Again, considering the worries over DU are focused on the possibility that uranium ions are retained by sensitive cells (such as commonly happens in the well-known process of bioaccumulation), quite possibly through DNA binding, it is difficult to feel overly comforted by this study.