Effect of acetaminophen administration to rats chronically exposed to depleted uranium

International Nuclear Information System (INIS)

Gueguen, Y.; Grandcolas, L.; Baudelin, C.; Grison, S.; Tissandie, E.; Jourdain, J.R.; Paquet, F.; Voisin, P.; Aigueperse, J.; Gourmelon, P.; Souidi, M.

2007-01-01

The extensive use of depleted uranium (DU) in both civilian and military applications results in the increase of the number of human beings exposed to this compound. We previously found that DU chronic exposure induces the expression of CYP enzymes involved in the metabolism of xenobiotics (drugs). In order to evaluate the consequences of these changes on the metabolism of a drug, rats chronically exposed to DU (40 mg/l) were treated by acetaminophen (APAP, 400 mg/kg) at the end of the 9-month contamination. Acetaminophen is considered as a safe drug within the therapeutic range but in the case of overdose or in sensitive animals, hepatotoxicity and nephrotoxicity could occur. In the present work, plasma concentration of APAP was higher in the DU group compared to the non-contaminated group. In addition, administration of APAP to the DU-exposed rats increased plasma ALT (p < 0.01) and AST (p < 0.05) more rapidly than in the control group. Nevertheless, no histological alteration of the liver was observed but renal injury characterized by incomplete proximal tubular cell necrosis was higher for the DU-exposed rats. Moreover, in the kidney, CYP2E1 gene expression, an important CYP responsible for APAP bioactivation and toxicity, is increased (p < 0.01) in the DU-exposed group compared to the control group. In the liver, CYP's activities were decreased between control and DU-exposed rats. These results could explain the worse elimination of APAP in the plasma and confirm our hypothesis of a modification of the drug metabolism following a DU chronic contamination

Study of the total uranium in underground water in the city of Jimenez, Chihuahua

International Nuclear Information System (INIS)

Renteria V, M.

2004-01-01

Samples of water of wells in the city of Jimenez, Chihuahua were analyzed, and its were determined the content of total uranium. It was used the technique of extraction of uranium from water adding Bis ( 2- ethylexyl) phosphate and scintillating Beta plate Hi safe, and the measures of the activities were carried out in the portable scintillation detector Thiathler- O Y HIDEX. The obtained interval of concentrations was 0.12 to 0.26 Bq/l that it is finds below the maximum permissible limits that it manages the Mexican regulation. It was found a significant correlation among the concentration of uranium and those total solid dissolved present in the samples. (Author)

Measurement of the Total Cross Section of Uranium-Uranium Collisions at √{sNN} = 192 . 8 GeV

Science.gov (United States)

Baltz, A. J.; Fischer, W.; Blaskiewicz, M.; Gassner, D.; Drees, K. A.; Luo, Y.; Minty, M.; Thieberger, P.; Wilinski, M.; Pshenichnov, I. A.

2014-03-01

The total cross section of Uranium-Uranium at √{sNN} = 192 . 8 GeV has been measured to be 515 +/-13stat +/-22sys barn, which agrees with the calculated theoretical value of 487.3 barn within experimental error. That this total cross section is more than an order of magnitude larger than the geometric ion-ion cross section is primarily due to Bound-Free Pair Production (BFPP) and Electro-Magnetic Dissociation (EMD). Nearly all beam losses were due to geometric, BFPP and EMD collisions. This allowed the determination of the total cross section from the measured beam loss rates and luminosity. The beam loss rate is calculated from a time-dependent measurement of the total beam intensity. The luminosity is measured via the detection of neutron pairs in time-coincidence in the Zero Degree Calorimeters. Apart from a general interest in verifying the calculations experimentally, an accurate prediction of the losses created in the heavy ion collisions is of practical interest for the LHC, where collision products have the potential to quench cryogenically cooled magnets.

Comparison of total and cold-extractable uranium in stream sediments of the southwestern Karoo supergroup, South Africa

International Nuclear Information System (INIS)

Jakob, W.R.O.; Smit, M.C.B.; Murphy, G.C.

1979-01-01

In order to evaluate the usefullness of cold-extractable uranium as a tool of uranium prospecting in stream sediments of the southwestern Karoo, South Africa, ten orientation studies were conducted near known mineralisation jointly by the Atomic Energy Board and the Geological Survey of South Africa. These indicate that the topography determines the nature of the dispersion. In areas of moderate to high relief the total uranium content of the stream sediment gives dispersion trains up to about 500 m from the mineralisation, and peak-to-background ratios of about 3. The use of cold-extractable uranium doubles the length of the dispersion, and peak-to-background ratios are greater than 10 and may be as high as 35. In areas of low relief, the total uranium content of the sediment gives low anomalies, with short dispersion downstream. Cold-extractable uranium gives anomalies 500-1 000 m from the mineralisation. This is interpreted to be due to the longer residence time of the clay minerals in the stream. In order to test the applicability of cold-extractable uranium on a regional scale, 720 samples were collected at a density of one sample per square kilometre. Statistical treatment of the data shows the U content of the stream sediments, to be log-normally distributed. For cold-extractable uranium, polymodal distributions, apparently representing background and anomalous samples, can be separated with a high rate of success, and meaningful threshold values can be assigned. This is not the case for the total uranium content of the stream sediments [af

Assessment of uranium exposure from total activity and 234U:238U activity ratios in urine

International Nuclear Information System (INIS)

Nicholas, T.; Bingham, D.

2011-01-01

Radiation workers at Atomic Weapons Establishment (AWE) are monitored for uranium exposure by routine bioassay sampling (primarily urine sampling). However, the interpretation of uranium in urine and faecal results in terms of occupational intakes is difficult because of the presence of uranium due to intakes from environmental (dietary) sources. For uranium in urine data obtained using current analytical techniques at AWE, the mean, median and standard deviation of excreted uranium concentrations were 0.006, 0.002 and 0.012 μg per g creatinine, respectively. These values are consistent with what might be expected from local dietary intakes and the knowledge that occupational exposures at AWE are likely to be very low. However, some samples do exceed derived investigation levels (DILs), which have been set up taking account of the likely contribution from environmental sources. We investigate how the activity and isotopic composition of uranium in the diet affects the sensitivity of uranium in urine monitoring for occupational exposures. We conclude that DILs based on both total uranium in urine activity and also 234 U: 238 U ratios are useful given the likely variation in dietary contribution for AWE workers. Assuming a background excretion rate and that the enrichment of the likely exposure is known, it is possible to assess exposures using 234 U: 238 U ratios and/or total uranium activity. The health implications of internalised uranium, enriched to 235 U, centre on its nephrotoxicity; the DILs for bioassay samples at AWE are an order of magnitude below the conservative recommendations made by the literature. (authors)

Uranium soft x-ray total attenuation coefficients

International Nuclear Information System (INIS)

Del Grande, N.K.; Oliver, A.J.

1981-01-01

Uranium total attenuation coefficients were measured continuously from 0.84 to 6.0 keV and at selected higher energies using a vacuum single crystal diffractometer and flow-proportional counter. Statistical fluctuations ranged from 0.5% to 2%. The overall accuracy was 3%. Prominent structure was measured within 20 eV of the M 5 (3.552 keV) and M 4 (3.728 keV) edges. Jump ratios were determined from log-log polynomial fits to data at energies apart from the near-edge regions. These data were compared with calculations based on a relativistic HFS central potential model and with previously tabulated data

Standard test method for analysis of total and isotopic uranium and total thorium in soils by inductively coupled plasma-mass spectrometry

CERN Document Server

American Society for Testing and Materials. Philadelphia

2008-01-01

1.1 This test method covers the measurement of total uranium (U) and thorium (Th) concentrations in soils, as well as the determination of the isotopic weight percentages of 234U, 235U, 236U, and 238U, thereby allowing for the calculation of individual isotopic uranium activity or total uranium activity. This inductively coupled plasma-mass spectroscopy (ICP-MS) method is intended as an alternative analysis to methods such as alpha spectroscopy or thermal ionization mass spectroscopy (TIMS). Also, while this test method covers only those isotopes listed above, the instrumental technique may be expanded to cover other long-lived radioisotopes since the preparation technique includes the preconcentration of the actinide series of elements. The resultant sample volume can be further reduced for introduction into the ICP-MS via an electrothermal vaporization (ETV) unit or other sample introduction device, even though the standard peristaltic pump introduction is applied for this test method. The sample preparatio...

Determination of uranium in the red blood cells of the workers in the chemical processing of uranium ore

International Nuclear Information System (INIS)

Nosek, J.; Simkova, M.; Kukula, F.; Musil, K.

1975-04-01

Neutron activation analysis was used in determining uranium in the venous blood erythrocytes of controls and of workers exposed to occupational hazards in a uranium chemical treatment plant. While 4.1 +- 2.6 ppb of uranium was found in dry matter of the erythrocytes in controls, 6.5 +- 2.1 ppb of uranium was ascertained in dry matter of the erythrocytes in occupationally exposed workers of a wet preparation plant, and 37.2 +- 20.2 ppb of uranium in the erythrocytes in workers of a dry cleaning plant. (author)

Effect of intratracheally instilled depleted uranium on immunological function of rats

International Nuclear Information System (INIS)

You Hanhu; Yang Zhihua; Cao Zhenshan; Zhu Maoxiang; Liu Xingrong

2004-01-01

Objective: To study immunological effects of depleted uranium in rats. Methods: Wistar rats were exposed to depleted uranium by single intratracheal instillation. Body weight and peripheral blood cells were measured weekly and immunological functions were evaluated by weight coefficient of immune organs, plague forming cells of splenocytes, total and subpopulation counts of lymphocytes in thymus. Results: Early after administration, body weight decreased and red blood cells as well as platelets reduced while white blood cells increased, which returned to normal within 1 or 2 months. Immunological functions of splenocytes and thymocytes were affected dose-dependently by depleted uranium. Conclusion: Depleted uranium induces immunological dysfunction in rats. (authors)

The Toxicity of Depleted Uranium

Directory of Open Access Journals (Sweden)

Wayne Briner

2010-01-01

Full Text Available Depleted uranium (DU is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed.

Elemental imaging of kidneys of adult rats exposed to uranium acetate

Energy Technology Data Exchange (ETDEWEB)

Homma-Takeda, S. [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)], E-mail: shino_ht@nirs.go.jp; Terada, Y. [Japan Synchrotron Radiation Research Institute, Mikazuki, Hyogo 679-5198 (Japan); Nakata, A.; Sahoo, S.K.; Yoshida, S. [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Ueno, S. [School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628 (Japan); Inoue, M. [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Iso, H.; Ishikawa, T.; Konishi, T.; Imaseki, H. [Fundamental Technology Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Shimada, Y. [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)

2009-06-15

Concern about the toxicity of depleted uranium for military use has increased recently. Renal toxicity is the hallmark effect of uranium exposure. However, the dynamics and distribution of uranium in the kidney are not well understood. Here, we determined the precise distribution of uranium and essential elements in the rat kidney using microbeam scanning particle-induced X-ray emission (micro-PIXE) and synchrotron radiation X-ray fluorescence (SR-XRF). Uranium accumulation in the rat kidney reached a maximum at 1 day after the subcutaneous (s.c.) administration of 2 mg U/kg of uranium acetate and then gradually decreased. At 3 h after administration, uranium was distributed mainly in the proximal tubules of the inner zone of the cortex and in the outer stripe of the outer medulla, and absorbed by the proximal tubule epithelium. Iron was localized more in the inside of the outer medulla than uranium, while phosphorus, potassium, sulfur and zinc were equally distributed in the cortex and the outer stripe of the outer medulla. At 3 days after administration, the number of apoptotic cells increased and cells were lost from the proximal tubules. Uranium was detectable mainly in the outer stripe of the outer medulla at 15 days, suggesting that the renal distribution of uranium is site-selective and causes site-specific renal lesions.

Study of the total uranium in underground water in the city of Jimenez, Chihuahua; Estudio del uranio total en agua subterranea en la Ciudad de Jimenez, Chihuahua

Energy Technology Data Exchange (ETDEWEB)

Renteria V, M. [Centro de Investigacion de Materiales Avanzados (CIMAV), Av. Miguel de Cervantes Saavedra 120, 31109 Chihuahua (Mexico)]. e-mail: marusia.renteria@cimav.edu.mx

2004-07-01

Samples of water of wells in the city of Jimenez, Chihuahua were analyzed, and its were determined the content of total uranium. It was used the technique of extraction of uranium from water adding Bis ( 2- ethylexyl) phosphate and scintillating Beta plate Hi safe, and the measures of the activities were carried out in the portable scintillation detector Thiathler- O Y HIDEX. The obtained interval of concentrations was 0.12 to 0.26 Bq/l that it is finds below the maximum permissible limits that it manages the Mexican regulation. It was found a significant correlation among the concentration of uranium and those total solid dissolved present in the samples. (Author)

Trace determination of uranium in fertilizer samples by total ...

Indian Academy of Sciences (India)

Uranium is reported to be present in phosphate fertilizers. The recovery of uranium from the fertilizers is important because it can be used as fuel in nuclear reactors and also because of environmental concerns. For both these activities suitable method of uranium determinations at trace levels in these fertilizers are required.

Total reflection X-ray spectroscopy as a rapid analytical method for uranium determination in drainage water

International Nuclear Information System (INIS)

Matsuyama, Tsugufumi; Sakai, Yasuhiro; Izumoto, Yukie; Imaseki, Hitoshi; Hamano, Tsuyoshi; Yoshii, Hiroshi

2017-01-01

Uranium concentrations in drainage water are typically determined by α-spectrometry. However, due to the low specific radioactivity of uranium, the evaporation of large volumes of drainage water, followed by several hours of measurements, is required. Thus, the development of a rapid and simple detection method for uranium in drainage water would enhance the operation efficiency of radiation control workers. We herein propose a novel methodology based on total reflection X-ray fluorescence (TXRF) for the measurement of uranium in contaminated water. TXRF is a particularly desirable method for the rapid and simple evaluation of uranium in contaminated water, as chemical pretreatment of the sample solution is not necessary, measurement times are typically several seconds, and the required sample volume is low. We herein employed sample solutions containing several different concentrations of uranyl acetate with yttrium as an internal standard. The solutions were placed onto sample holders, and were dried prior to TXRF measurements. The relative intensity, otherwise defined as the net intensity ratio of the Lα peak of uranium to the Kα peak of yttrium, was directly proportional to the uranium concentration. Using this method, a TXRF detection limit for uranium in contaminated water of 0.30 μg/g was achieved. (author)

Uranium

International Nuclear Information System (INIS)

Hamdoun, N.A.

2007-01-01

The article includes a historical preface about uranium, discovery of portability of sequential fission of uranium, uranium existence, basic raw materials, secondary raw materials, uranium's physical and chemical properties, uranium extraction, nuclear fuel cycle, logistics and estimation of the amount of uranium reserves, producing countries of concentrated uranium oxides and percentage of the world's total production, civilian and military uses of uranium. The use of depleted uranium in the Gulf War, the Balkans and Iraq has caused political and environmental effects which are complex, raising problems and questions about the effects that nuclear compounds left on human health and environment.

Assessing the Renal Toxicity of Capstone Depleted Uranium Oxides and Other Uranium Compounds

International Nuclear Information System (INIS)

Roszell, Laurie E.; Hahn, Fletcher; Lee, Robyn B.; Parkhurst, MaryAnn

2009-01-01

The primary target for uranium toxicity is the kidney. The most frequently used guideline for uranium kidney burdens is the International Commission on Radiation Protection (ICRP) value of 3 (micro)g U/g kidney, a value that is based largely upon chronic studies in animals. In the present effort, we have developed a risk model equation to assess potential outcomes of acute uranium exposure. Twenty-seven previously published case studies in which workers were acutely exposed to soluble compounds of uranium (as a result of workplace accidents) were analyzed. Kidney burdens of uranium for these individuals were determined based on uranium in the urine, and correlated with health effects observed over a period of up to 38 years. Based upon the severity of health effects, each individual was assigned a score (- to +++) and then placed into an Effect Group. A discriminant analysis was used to build a model equation to predict the Effect Group based on the amount of uranium in the kidneys. The model equation was able to predict the Effect Group with 85% accuracy. The risk model was used to predict the Effect Group for Soldiers exposed to DU as a result of friendly fire incidents during the 1991 Gulf War. This model equation can also be used to predict the Effect Group of new cases in which acute exposures to uranium have occurred

Lung cancer mortality among nonsmoking uranium miners exposed to radon daughters

International Nuclear Information System (INIS)

Roscoe, R.J.; Steenland, K.; Halperin, W.E.; Beaumont, J.J.; Waxweiler, R.J.

1989-01-01

Radon daughters, both in the workplace and in the household, are a continuing cause for concern because of the well-documented association between exposure to radon daughters and lung cancer. To estimate the risk of lung cancer mortality among nonsmokers exposed to varying levels of radon daughters, 516 white men who never smoked cigarettes, pipes, or cigars were selected from the US Public Health Service cohort of Colorado Plateau uranium miners and followed up from 1950 through 1984. Age-specific mortality rates for nonsmokers from a study of US veterans were used for comparison. Fourteen deaths from lung cancer were observed among the nonsmoking miners, while 1.1 deaths were expected, yielding a standardized mortality ratio of 12.7 with 95% confidence limits of 8.0 and 20.1. These results confirm that exposure to radon daughters in the absence of cigarette smoking is a potent carcinogen that should be strictly controlled

Lung cancer mortality among nonsmoking uranium miners exposed to radon daughters

International Nuclear Information System (INIS)

Roscoe, R.J.; Stenland, K.; Halperin, W.E.; Waxweiler, R.J.

1990-01-01

This paper reports on radon daughters, both in the workplace and in the household, that are a continuing cause of concern because of the well-documented association between exposure to radon daughters and lung cancer. To estimate the risk of lung cancer mortality among nonsmokers exposed to varying levels of radon daughters, 516 white men who never smoked cigarettes, pipes, or cigars were selected from the U.S. Public Health Service cohort of Colorado Plateau uranium miners and followed up from 1950 through 1984. Age-specific mortality rates for nonsmokers from a study of U.S. veterans were used for comparison. Fourteen deaths from lung cancer were observed among the nonsmoking miners, while 1.1 deaths were expected, yielding a standardized mortality radio of 12.7 with 95% confidence limits of 8.0 and 20.1. These results confirm that exposure to radon daughters in the absence of cigarette smoking is a potent carcinogen that should be strictly controlled

Mortality (1968-2008) in a French cohort of uranium enrichment workers potentially exposed to rapidly soluble uranium compounds.

Science.gov (United States)

Zhivin, Sergey; Guseva Canu, Irina; Samson, Eric; Laurent, Olivier; Grellier, James; Collomb, Philippe; Zablotska, Lydia B; Laurier, Dominique

2016-03-01

Until recently, enrichment of uranium for civil and military purposes in France was carried out by gaseous diffusion using rapidly soluble uranium compounds. We analysed the relationship between exposure to soluble uranium compounds and exposure to external γ-radiation and mortality in a cohort of 4688 French uranium enrichment workers who were employed between 1964 and 2006. Data on individual annual exposure to radiological and non-radiological hazards were collected for workers of the AREVA NC, CEA and Eurodif uranium enrichment plants from job-exposure matrixes and external dosimetry records, differentiating between natural, enriched and depleted uranium. Cause-specific mortality was compared with the French general population via standardised mortality ratios (SMR), and was analysed via Poisson regression using log-linear and linear excess relative risk models. Over the period of follow-up, 131 161 person-years at risk were accrued and 21% of the subjects had died. A strong healthy worker effect was observed: all causes SMR=0.69, 95% CI 0.65 to 0.74. SMR for pleural cancer was significantly increased (2.3, 95% CI 1.06 to 4.4), but was only based on nine cases. Internal uranium and external γ-radiation exposures were not significantly associated with any cause of mortality. This is the first study of French uranium enrichment workers. Although limited in statistical power, further follow-up of this cohort, estimation of internal uranium doses and pooling with similar cohorts should elucidate potential risks associated with exposure to soluble uranium compounds. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Nuclear toxicology file: ecological consequences of a chronic exposure to uranium

International Nuclear Information System (INIS)

Adam, Ch.; Alonzo, F.; Bonzom, J.M.; Gilbin, R.; Garnier-Laplace, J.; Simon, O.

2008-01-01

This article presents the thought process and the current developments, based on the experimental acquisition of the answers of the alive organisms to the chronic low dose exposures of natural uranium in fresh water, to identify the consequences of this exposure on the populations composing the ecosystems. The results acquired on the zebra fish (Danio rerio) show an impact on the first steps of development. We note a delay of hatching upon 40 % from 20 μg/l of uranium. This delay comes along with a decrease of the size and with a reduction of the growth of larvas as well as with an increase of their mortality for higher uranium concentration. For adults exposed to uranium a decrease of reproduction success is observed from a concentration of 20μg/l. The consequences in term of fertility (total number of laid roes) are drastic, with a reduction of a factor 2 and 60, for the organisms exposed respectively to 20 and 250 μg/l of uranium. A study was also made on several generations (populations of benthic invertebrates), it suggests an adaptation (genetic selection) but created a bigger fragility to a new environment even identical to their environment of origin with notably a decrease of the reproduction. (N.C.)

Depleted and enriched uranium exposure quantified in former factory workers and local residents of NL Industries, Colonie, NY USA

International Nuclear Information System (INIS)

Arnason, John G.; Pellegri, Christine N.; Moore, June L.; Lewis-Michl, Elizabeth L.; Parsons, Patrick J.

2016-01-01

Background: Between 1958 and 1982, NL Industries manufactured components of enriched (EU) and depleted uranium (DU) at a factory in Colonie NY, USA. More than 5 metric tons of DU was deposited as microscopic DU oxide particles on the plant site and surrounding residential community. A prior study involving a small number of individuals (n=23) indicated some residents were exposed to DU and former workers to both DU and EU, most probably through inhalation of aerosol particles. Objectives: Our aim was to measure total uranium [U] and the uranium isotope ratios: 234 U/ 238 U; 235 U/ 238 U; and 236 U/ 238 U, in the urine of a cohort of former workers and nearby residents of the NLI factory, to characterize individual exposure to natural uranium (NU), DU, and EU more than 3 decades after production ceased. Methods: We conducted a biomonitoring study in a larger cohort of 32 former workers and 99 residents, who may have been exposed during its period of operation, by measuring Total U, NU, DU, and EU in urine using Sector Field Inductively Coupled Plasma - Mass Spectrometry (SF-ICP-MS). Results: Among workers, 84% were exposed to DU, 9% to EU and DU, and 6% to natural uranium (NU) only. For those exposed to DU, urinary isotopic and [U] compositions result from binary mixing of NU and the DU plant feedstock. Among residents, 8% show evidence of DU exposure, whereas none shows evidence of EU exposure. For residents, the [U] geometric mean is significantly below the value reported for NHANES. There is no significant difference in [U] between exposed and unexposed residents, suggesting that [U] alone is not a reliable indicator of exposure to DU in this group. Conclusions: Ninety four percent of workers tested showed evidence of exposure to DU, EU or both, and were still excreting DU and EU decades after leaving the workforce. The study demonstrates the advantage of measuring multiple isotopic ratios (e.g., 236 U/ 238 U and 235 U/ 238 U) over a single ratio ( 235 U/ 238 U

Uranium toxicology

International Nuclear Information System (INIS)

Ferreyra, Mariana D.; Suarez Mendez, Sebastian

1997-01-01

In this paper are presented the methods and procedures optimized by the Nuclear Regulatory Authority (ARN) for the determination of: natural uranium mass, activity of enriched uranium in samples of: urine, mucus, filters, filter heads, rinsing waters and Pu in urine, adopted and in some cases adapted, by the Environmental Monitoring and Internal Dosimetry Laboratory. The analyzed material corresponded to biological and environmental samples belonging to the staff professionally exposed that work in plants of the nuclear fuel cycle. For a better comprehension of the activities of this laboratory, it is included a brief description of the uranium radiochemical toxicity and the limits internationally fixed to preserve the workers health

National Uranium Resource Evaluation: Lovelock Quadrangle, Nevada and California

International Nuclear Information System (INIS)

Berry, V.P.; Bradley, M.T.; Nagy, P.A.

1982-08-01

Uranium resources of the Lovelock Quadrangle, Nevada and California, were evaluated to a depth of 1500 m using available surface and subsurface geological information. Uranium occurrences reported in the literature and in reports of the Atomic Energy Commission were located, sampled, and described in detail. Areas of anomalous radioactivity, as interpreted from the aerial radiometric reconnaissance survey and from the hydrochemical and stream-sediment reconnaissance survey reports, were also investigated. A general reconnaissance of the geologic environments exposed in surface outcrops was carried out; and over 400 rock, sediment, and water geochemical analyses were made from the samples taken. Additionally, 119 rock samples were petrographically studied. A total of 21 occurrences were located, sampled, and described in detail. Six uranium occurrences, previously unreported in the literature, were located during hydrogeochemical and stream-sediment reconnaissance, aerial radiometric reconnaissance survey followup, or general outcrop reconnaissance. Nine areas of uranium favorability were delineated within the Lovelock Quadrangle. One area, which contains the basal units of the Hartford Hill Rhyolite, is favorable for hydroallogenic uranium deposits. Eight areas are favorable for uranium deposits in playa sediments. These playas are considered favorable for nonmarine carbonaceous sediment deposits and evaporative deposits. The total volume of rock in favorable areas of the Lovelock Quadrangle is estimated to be 190 km 3 . The remaining geologic units are considered to be unfavorable for uranium deposits. These include upper Paleozoic and Mesozoic volcanic, plutonic, sedimentary, and metamorphic rocks. Also unfavorable are Tertiary and Quaternary volcanic flows and intrusive phases, tuffs, and sediments

Assesment of uranium ore mining impact on the health of occupationally exposed personnel and surrounding communities

International Nuclear Information System (INIS)

Ionasu, P.

2000-01-01

The working conditions of radioactive ore mining are characterized by atmospheric accumulation of radon and its products generated by alpha decay at the working site. This phenomenon induces a specific pulmonary pathology, named bronchopulmonary carcinoma. Its incidence is associated with radon exposure. This fact is confirmed by the studies performed over a period of 20 years at the mining sites where exploration, exploitation, transport and preparation of radioactive ores were carried out. The frequency of occurrence of bronchopulmonary carcinoma is 4-5 higher to miners working in the uranium mines comparing to the non-working inhabitants in the control area. The people working in radioactive environment, retired people from these activities, as well as the control human population in the areas close to the nuclear units, personnel of non-radioactive mines as well as populations of other areas, without nuclear activities, were medically examined. From the statistical interpretation of the results, the following conclusions have been drawn: incidence of death from respiratory cancer is higher in miners as compared with control population, the average age of the deceased people was lower for miners by about 5 years; occupational in service mean life was 11.3 years in uranium mines, as compared to 16.5 years in non ferrous mines and 15.1 years in coal mines; average latency time was 25 years in case of uranium mine workers, as compared to 27.4 years and 29.2 years in case of non ferrous and coal miners, respectively; cumulate exposure to radon and its descendants was 345 WLM for uranium miners as compared to 66 WLM and 58 WLM in case of non ferrous and coal miners, respectively. Also, the cancer incidence in smokers exposed to radon and its descendant was found to be increased as compared with smokers in control population. Measures for reducing the radiation effects are proposed. (authors)

Patch testing with uranyl acetate in veterans exposed to depleted uranium during the 1991 Gulf war and the Iraqi conflict.

Science.gov (United States)

Shvartsbeyn, Marianna; Tuchinda, Papapit; Gaitens, Joanna; Squibb, Katherine S; McDiarmid, Melissa A; Gaspari, Anthony A

2011-01-01

The Depleted Uranium Follow-Up Program is a clinical surveillance program run by the Baltimore Veterans Affairs Medical Center since 1993 for veterans of the Gulf and Iraqi wars who were exposed to depleted uranium (DU) as a result of "friendly-fire" incidents. In 2009, 40 veterans from this cohort were screened for skin reactivity to metals by patch-testing with extended metal series and uranyl acetate (0.25%, 2.5%, and 25%). A control arm comprised 46 patients without any known occupational exposures to DU who were seen at the University of Maryland Dermatology Clinic for evaluation of allergic contact dermatitis. Excluding irritant reactions, no patch-test reactions to uranyl acetate were observed in the participants. Irritant reactions to DU were more common in the clinic cohort, likely reflective of the demographic differences between the two arms of the study. Biologic monitoring of urine uranium concentrations in the DU program participants with 24-hour urine samples showed evidence of percutaneous uranium absorption from the skin patches. We conclude that dermatitis observed in a subset of the veterans was unrelated to their military DU exposure. Our data suggest that future studies of skin testing with uranyl acetate should utilize 0.25%, the least irritating concentration.

Trace determination of uranium in fertilizer samples by total ...

Indian Academy of Sciences (India)

the fertilizers is important because it can be used as fuel in nuclear reactors and also because of en- vironmental concerns. ... The amounts of uranium in four fertilizer samples of Hungarian origin were determined by ... TXRF determination of uranium from phosphate fertilizers of Hungarian origin and the preliminary results ...

Individual radiological monitoring for exposed personnel of Nuclear Fuel Plant at Pitesti

International Nuclear Information System (INIS)

Ivana, T.; Epure, Gh.

2010-01-01

In the activity of nuclear fuel fabrication of CANDU type, based on natural and depleted uranium, individual radiological monitoring of the personnel exposed to ionizing radiation is very carefully approached. For Nuclear Fuel Plant (NFP) facility, where uranium appears in bulk and itemized form, measures for individual radiological monitoring are established by Radiological Safety Manual (MSR) in accordance with national and international legislation. All NFP employees are classified in either category A or category B of exposure to ionizing radiation. The classification is a function of type of activity and magnitude of exposure. All the exposed personnel are monitored for external doses (from gamma radiation) by measuring the equivalent dose H p (10) with monthly frequency. The system used for external individual dosimetric monitoring is based on the thermoluminescent dosimeter (TLD) of PANASONIC type UD813AS14. The NFP incorporates an in-house dosimetric laboratory notified by Romanian regulatory body CNCAN (National Commission for Control of Nuclear Activities). The workers handling nuclear materials are exposed to internal intake of uranium, mainly by inhalation. For internal doses monitoring is included part of exposed employees working directly with radioactive open sources (pulverulent or liquid nuclear materials), UO 2 sinterable powder, green pellets, sintered pellets, scrap and radioactive effluents. The estimation of internal exposure is made quarterly using the results from radioactive airborne monitors operating in the working places. The internal dose of each person exposed to open sources is calculated taking into account the rate of breathing, the time spent at the work place and the dose-activity coefficient (variable function of uranium absorption rate). The total effective individual dose is obtained by summing the external dose and internal dose (E=E ext +E int ). For conformity, the total effective individual dose (E) is compared with dose

Depleted and enriched uranium exposure quantified in former factory workers and local residents of NL Industries, Colonie, NY USA

Energy Technology Data Exchange (ETDEWEB)

Arnason, John G. [Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York State Department of Health, P.O. Box 509, Albany, NY 12201-0509 (United States); Department of Environmental Health Sciences, School of Public Health, The University at Albany, P.O. Box 509, Albany, NY 12201-0509 (United States); Pellegri, Christine N. [Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York State Department of Health, P.O. Box 509, Albany, NY 12201-0509 (United States); Moore, June L.; Lewis-Michl, Elizabeth L. [Bureau of Environmental and Occupational Epidemiology, Center for Environmental Health, New York State Department of Health, Albany, NY (United States); Parsons, Patrick J., E-mail: patrick.parsons@health.ny.gov [Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York State Department of Health, P.O. Box 509, Albany, NY 12201-0509 (United States); Department of Environmental Health Sciences, School of Public Health, The University at Albany, P.O. Box 509, Albany, NY 12201-0509 (United States)

2016-10-15

Background: Between 1958 and 1982, NL Industries manufactured components of enriched (EU) and depleted uranium (DU) at a factory in Colonie NY, USA. More than 5 metric tons of DU was deposited as microscopic DU oxide particles on the plant site and surrounding residential community. A prior study involving a small number of individuals (n=23) indicated some residents were exposed to DU and former workers to both DU and EU, most probably through inhalation of aerosol particles. Objectives: Our aim was to measure total uranium [U] and the uranium isotope ratios: {sup 234}U/{sup 238}U; {sup 235}U/{sup 238}U; and {sup 236}U/{sup 238}U, in the urine of a cohort of former workers and nearby residents of the NLI factory, to characterize individual exposure to natural uranium (NU), DU, and EU more than 3 decades after production ceased. Methods: We conducted a biomonitoring study in a larger cohort of 32 former workers and 99 residents, who may have been exposed during its period of operation, by measuring Total U, NU, DU, and EU in urine using Sector Field Inductively Coupled Plasma - Mass Spectrometry (SF-ICP-MS). Results: Among workers, 84% were exposed to DU, 9% to EU and DU, and 6% to natural uranium (NU) only. For those exposed to DU, urinary isotopic and [U] compositions result from binary mixing of NU and the DU plant feedstock. Among residents, 8% show evidence of DU exposure, whereas none shows evidence of EU exposure. For residents, the [U] geometric mean is significantly below the value reported for NHANES. There is no significant difference in [U] between exposed and unexposed residents, suggesting that [U] alone is not a reliable indicator of exposure to DU in this group. Conclusions: Ninety four percent of workers tested showed evidence of exposure to DU, EU or both, and were still excreting DU and EU decades after leaving the workforce. The study demonstrates the advantage of measuring multiple isotopic ratios (e.g., {sup 236}U/{sup 238}U and {sup 235}U

Uranium resources in New Mexico

International Nuclear Information System (INIS)

McLemore, V.T.; Chenoweth, W.L.

1989-01-01

For nearly three decades (1951-1980), the Grants uranium district in northwestern New Mexico produced more uranium than any other district in the world. The most important host rocks containing economic uranium deposits in New Mexico are sandstones within the Jurassic Morrison Formation. Approximately 334,506,000 lb of U 3 O 8 were produced from this unit from 1948 through 1987, accounting for 38% of the total uranium production from the US. All of the economic reserves and most of the resources in New Mexico occur in the Morrison Formation. Uranium deposits also occur in sandstones of Paleozoic, Triassic, Cretaceous, Tertiary, and Quaternary formations; however, only 468,680 lb of U 3 O 8 or 0.14% of the total production from New Mexico have been produced from these deposits. Some of these deposits may have a high resource potential. In contrast, almost 6.7 million lb of U 3 O 8 have been produced from uranium deposits in the Todilto Limestone of the Wanakah Formation (Jurassic), but potential for finding additional economic uranium deposits in the near future is low. Other uranium deposits in New Mexico include those in other sedimentary rocks, vein-type uranium deposits, and disseminated magmatic, pegmatitic, and contact metasomatic uranium deposits in igneous and metamorphic rocks. Production from these deposits have been insignificant (less than 0.08% of the total production from New Mexico), but there could be potential for medium to high-grade, medium-sized uranium deposits in some areas. Total uranium production from New Mexico from 1948 to 1987 amounts to approximately 341,808,000 lb of U 3 O 8 . New Mexico has significant uranium reserves and resources. Future development of these deposits will depend upon an increase in price for uranium and lowering of production costs, perhaps by in-situ leaching techniques

Radon problem in uranium industry

International Nuclear Information System (INIS)

Khan, A.H.; Raghavayya, M.

1991-01-01

Radon emission is invariably associated with the mining and processing of uranium ores. Radon (sup(222)Rn) enters mine atmosphere through diffusion from exposed ore body, fractures and fissures in the rocks and is also brought in by ground water. Being the progenitor of a series of short lived radioisotopes it contributes over 70% of the radiation dose to mine workers and thus accounts for nearly 30% of the total radiation doses received by workers in the whole nuclear industry. This paper summarises the data on radon emanation from the ore body, backfilled sands and mine water. Radon and its progeny concentrations in different haulage levels and stopes of the Jaduguda uranium mine are presented to emphasise the need for a well planned ventilation system to control radiation exposure of miners. Results of radon monitoring from a few exploratory uranium mines are included to indicate the need for a good ventilation system from inception of the mining operations. Relative contribution of mine exhaust and tailings surfaces to the environmental radon are also given. Some instruments developed locally for monitoring of radon and its progeny in mines and in the environment are briefly described to indicate the progress made in this field. (author). 17 refs., 2 figs., 6 tabs

Uranium in Malwa region of Punjab, India

International Nuclear Information System (INIS)

Kochhar, Naresh; Dadwal, Veena; Balaram, V.

2012-01-01

It is well known in Punjab that the Malwa region shows a very high incidence of cancer, stunted growth and other neurological disorders. The high values of uranium have been attributed to Kota nuclear power plant; Khushab heavy water plant in Pakistan; and uranium - carrying winds from Afghanistan, without any scientific basis. Though Malwa is a part of Punjab, geologically it is more akin to Haryana and Rajasthan. Uranium is a naturally occurring radioactive element which is present in trace in rocks, minerals plants and natural waters. It occurs along with thorium and potassium in granitic rocks. It has the property to get dissolved in water in hexavalent form at a normal pH of 5 to 7. It gets precipitated in the reducing environment in tetravalent form and form complexes such as hydroxides, phosphate, sulfate, carbonate etc. Uranium compounds are soluble in water, very mobile and travel kilometers. When the bed rocks containing uranium and thorium and other elements are exposed to sun, rain, wind, they get weathered and breakdown to form soil. Uranium gets dispersed in matrix, soil and finally gets re-deposited in areas/pockets where reducing conditions are present. Hence we get higher concentration of uranium in pockets. There are no rocks exposed on the surface in the SW Punjab. However the rocks of Aravalli-Delhi ridge and Malani granites and rhyohtes are exposed at Tusham district Bhiwani just south of the region. These rocks take a northwest turn from Tusham and become submerged under the Punjab Plains only to get resurfaced at Kirana Hills Pakistan. The gravity data have delineated 6 km wide and 240 km long per shaped body under the Punjab plains covering the SW Punjab. The Tusham granites are high heat producing granites that is they are enriched in uranium, thorium and Potasium. The uranium concentration in Tusham granites is 8 to 11 .5 parts per million (ppm) as compared to the normal value of 4.5 in granites in general. The average crustal values is 2

Nephrotoxicity of uranium in drinking water from private drilled wells

International Nuclear Information System (INIS)

Selden, Anders I.; Lundholm, Cecilia; Edlund, Bror; Hoegdahl, Camilla; Ek, Britt-Marie; Bergstroem, Bernt E.; Ohlson, Carl-Goeran

2009-01-01

Objectives: To investigate the association between uranium in drinking water from drilled wells and aspects of kidney function measured by sensitive urine tests. Methods: Three hundred and one of 398 eligible subjects (75.6%) aged 18-74 years with daily drinking water supplies from private drilled wells located in uranium-rich bedrock (exposed group) volunteered to participate along with 153 of 271 local controls (56.4%) who used municipal water. Participants responded to a questionnaire on their water consumption and general health, and provided a morning urine sample and drinking water for analysis. Results: The uranium content of well water samples (n=153) varied considerably (range 100 μg/l), while uranium levels in all samples of municipal water (n=14) were below the limit of quantification (0.2 μg/l). Urinary levels of uranium were more than eight times higher in exposed subjects than in controls (geometric means 38 and 4.3 ng/l, respectively; p 2 =0.66). Levels of albumin, β 2 -microglobulin, protein HC as well as kappa and lambda immunoglobulin chains in urine from exposed and controls were similar. The N-acetyl-β-D-glucosaminidase (NAG) activity was significantly lower in the exposed group vs. controls, possibly secondary to differential storage duration of samples from the two groups. Even in regression models adjusting for gender, age and smoking no association of uranium in water and the kidney function parameters was observed. Using uranium in urine in the entire study group as a marker of exposure, however, a tendency of exposure-related increases of β 2 -microglobulin, protein HC and kappa chains were noted. This tendency was enhanced after exclusion of subjects with diabetes mellitus from the analysis. Conclusions: Uranium levels in urine were strongly correlated to levels in drinking water from drilled wells. There were no clear signs of nephrotoxicity from uranium in drinking water at levels recorded in this study, but some indications of an

Criticality accident in uranium fuel processing plant. The estimation of the total number of fissions with related reactor physics parameters

International Nuclear Information System (INIS)

Nishina, Kojiro; Oyamatsu, Kazuhiro; Kondo, Shunsuke; Sekimoto, Hiroshi; Ishitani, Kazuki; Yamane, Yoshihiro; Miyoshi, Yoshinori

2000-01-01

This accident occurred when workers were pouring a uranium solution into a precipitation tank with handy operation against the established procedure and both the cylindrical diameter and the total mass exceeded the limited values. As a result, nuclear fission chain reactor in the solution reached not only a 'criticality' state continuing it independently but also an instantly forming criticality state exceed the criticality and increasing further nuclear fission number. The place occurring the accident at this time was not reactor but a place having not to form 'criticality' called by a processing process of uranium fuel. In such place, as because of relating to mechanism of chain reaction, it is required naturally for knowledge on the reactor physics, it is also necessary to understand chemical reaction in chemical process, and functions of tanks, valves and pumps mounted at the processes. For this purpose, some information on uranium concentration ratio, atomic density of nuclides largely affecting to chain reaction such as uranium, hydrogen, and so forth in the solution, shape, inner structure and size of container for the solution, and its temperature and total volume, were necessary for determining criticality volume of the accident uranium solution by using nuclear physics procedures. Here were described on estimation of energy emission in the JCO accident, estimation from analytical results on neutron and solution, calculation of various nuclear physics property estimation on the JCO precipitation tank at JAERI. (G.K.)

Physicochemical characterization of Capstone depleted uranium aerosols I: uranium concentration in aerosols as a function of time and particle size.

Science.gov (United States)

Parkhurst, Mary Ann; Cheng, Yung Sung; Kenoyer, Judson L; Traub, Richard J

2009-03-01

During the Capstone Depleted Uranium (DU) Aerosol Study, aerosols containing DU were produced inside unventilated armored vehicles (i.e., Abrams tanks and Bradley Fighting Vehicles) by perforation with large-caliber DU penetrators. These aerosols were collected and characterized, and the data were subsequently used to assess human health risks to personnel exposed to DU aerosols. The DU content of each aerosol sample was first quantified by radioanalytical methods, and selected samples, primarily those from the cyclone separator grit chambers, were analyzed radiochemically. Deposition occurred inside the vehicles as particles settled on interior surfaces. Settling rates of uranium from the aerosols were evaluated using filter cassette samples that collected aerosol as total mass over eight sequential time intervals. A moving filter was used to collect aerosol samples over time, particularly within the first minute after a shot. The results demonstrate that the peak uranium concentration in the aerosol occurred in the first 10 s after perforation, and the concentration decreased in the Abrams tank shots to about 50% within 1 min and to less than 2% after 30 min. The initial and maximum uranium concentrations were lower in the Bradley vehicle than those observed in the Abrams tank, and the concentration levels decreased more slowly. Uranium mass concentrations in the aerosols as a function of particle size were evaluated using samples collected in a cyclone sampler, which collected aerosol continuously for 2 h after perforation. The percentages of uranium mass in the cyclone separator stages ranged from 38 to 72% for the Abrams tank with conventional armor. In most cases, it varied with particle size, typically with less uranium associated with the smaller particle sizes. Neither the Abrams tank with DU armor nor the Bradley vehicle results were specifically correlated with particle size and can best be represented by their average uranium mass concentrations of 65

Impurities determination in uranium eluates by total reflection X-ray fluorescence

International Nuclear Information System (INIS)

Vazquez, Cristina; Bellavigna, Horacio J.; Eppis, Maria R.; Ramella, Jose L.

1999-01-01

The chemical control of impurities in nuclear materials is indispensable in order to assure an efficient operation of the reactors. The maximum concentration admitted depends of the elements and in most cases are in the parts per billion range. Conventional analytical methods require a pre-concentration treatment of the sample and a previous separation of the matrix (uranium). This paper investigates the use of the total reflection X-ray fluorescence as an alternative methodology for the determination of impurities in nuclear materials, namely K, Ca, Ti, Cr, Mn, Fe, Ni, Cu and As. The detection limits obtained were in the range of 0.1 to 20 ng/ml for a 1000 seconds counting time. (author)

Measurements of daily urinary uranium excretion in German peacekeeping personnel and residents of the Kosovo region to assess potential intakes of depleted uranium (DU)

International Nuclear Information System (INIS)

Oeh, U.; Priest, N.D.; Roth, P.; Ragnarsdottir, K.V.; Li, W.B.; Hoellriegl, V.; Thirlwall, M.F.; Michalke, B.; Giussani, A.; Schramel, P.; Paretzke, H.G.

2007-01-01

Following the end of the Kosovo conflict, in June 1999, a study was instigated to evaluate whether there was a cause for concern of health risk from depleted uranium (DU) to German peacekeeping personnel serving in the Balkans. In addition, the investigations were extended to residents of Kosovo and southern Serbia, who lived in areas where DU ammunitions were deployed. In order to assess a possible DU intake, both the urinary uranium excretion of volunteer residents and water samples were collected and analysed using inductively coupled plasma-mass spectrometry (ICP-MS). More than 1300 urine samples from peacekeeping personnel and unexposed controls of different genders and age were analysed to determine uranium excretion parameters. The urine measurements for 113 unexposed subjects revealed a daily uranium excretion rate with a geometric mean of 13.9 ng/d (geometric standard deviation (GSD) = 2.17). The analysis of 1228 urine samples from the peacekeeping personnel resulted in a geometric mean of 12.8 ng/d (GSD = 2.60). It follows that both unexposed controls and peacekeeping personnel excreted similar amounts of uranium. Inter-subject variation in uranium excretion was high and no significant age-specific differences were found. The second part of the study monitored 24 h urine samples provided by selected residents of Kosovo and adjacent regions of Serbia compared to controls from Munich, Germany. Total uranium and isotope ratios were measured in order to determine DU content. 235 U/ 238 U ratios were within ± 0.3% of the natural value, and 236 U/ 238 U was less than 2 x 10 -7 , indicating no significant DU in any of the urine samples provided, despite total uranium excretion being relatively high in some cases. Measurements of ground and tap water samples from regions where DU munitions were deployed did not show any contamination with DU, except in one sample. It is concluded that both peacekeeping personnel and residents serving or living in the Balkans

Lung Cancer in uranium miners

International Nuclear Information System (INIS)

Zhou Chundi; Fan Jixiong; Wang Liuhu; Huang Yiehan; Nie Guanghua

1987-01-01

This paper analyese the clinical data of 39 uranium miners with lung cancer and of 20 patients with lung cancer who have not been exposed to uranium as control. The age of uranium miners with lung cancer was 36∼61 with an average of 48.8, nine years earlier than that of the control group (57.3). In the uranium miner patients the right lung was more susceptible to cancer than the left, the ratio being 2.5:1. However, in the control group the right lung had an equal incidence of cancer as the left lung. The relative frequency of small cell anaplastic carcinoma in uranium miner was higher than that in the control group. In the miner patients the mean occupation history was 11.1 ± 5.2 years; the exposure dose to radon and its daughters in 50% patients was 0.504J(120 WLM). The etiologic factor of lung cancer in uranium miners is strongly attributed, in addition to smoking, to the exposure to radon and its daughters in uranium mines

Bioassay for uranium mill tailings

International Nuclear Information System (INIS)

Tschaeche, A.N.

1986-01-01

Uranium mill tailings are composed of fine sand that contains, among other things, some uranium (U/sup 238/ primarily), and all of the uranium daughters starting with /sup 230/Th that are left behind after the usable uranium is removed in the milling process. Millions of pounds of tailings are and continue to be generated at uranium mills around the United States. Discrete uranium mill tailings piles exist near the mills. In addition, the tailings materials were used in communities situated near mill sites for such purposes as building materials, foundations for buildings, pipe runs, sand boxes, gardens, etc. The Uranium Mill Tailings Remedial Action Project (UMTRAP) is a U.S. Department of Energy Program designed with the intention of removing or stabilizing the mill tailings piles and the tailings used to communities so that individuals are not exposed above the EPA limits established for such tailings materials. This paper discusses the bioassay programs that are established for workers who remove tailings from the communities in which they are placed

Czechoslovak uranium

International Nuclear Information System (INIS)

Pluskal, O.

1992-01-01

Data and knowledge related to the prospecting, mining, processing and export of uranium ores in Czechoslovakia are presented. In the years between 1945 and January 1, 1991, 98,461.1 t of uranium were extracted. In the period 1965-1990 the uranium industry was subsidized from the state budget to a total of 38.5 billion CSK. The subsidies were put into extraction, investments and geologic prospecting; the latter was at first, ie. till 1960 financed by the former USSR, later on the two parties shared costs on a 1:1 basis. Since 1981 the prospecting has been entirely financed from the Czechoslovak state budget. On Czechoslovak territory uranium has been extracted from deposits which may be classified as vein-type deposits, deposits in uranium-bearing sandstones and deposits connected with weathering processes. The future of mining, however, is almost exclusively being connected with deposits in uranium-bearing sandstones. A brief description and characteristic is given of all uranium deposits on Czechoslovak territory, and the organization of uranium mining in Czechoslovakia is described as is the approach used in the world to evaluate uranium deposits; uranium prices and actual resources are also given. (Z.S.) 3 figs

Chronic Exposure to Uranium from Gestation: Effects on Behavior and Neurogenesis in Adulthood.

Science.gov (United States)

Dinocourt, Céline; Culeux, Cécile; Legrand, Marie; Elie, Christelle; Lestaevel, Philippe

2017-05-17

Uranium exposure leads to cerebral dysfunction involving for instance biochemical, neurochemical and neurobehavioral effects. Most studies have focused on mechanisms in uranium-exposed adult animals. However, recent data on developing animals have shown that the developing brain is also sensitive to uranium. Models of uranium exposure during brain development highlight the need to improve our understanding of the effects of uranium. In a model in which uranium exposure began from the first day of gestation, we studied the neurobehavioral consequences as well as the progression of hippocampal neurogenesis in animals from dams exposed to uranium. Our results show that 2-month-old rats exposed to uranium from gestational day 1 displayed deficits in special memory and a prominent depressive-like phenotype. Cell proliferation was not disturbed in these animals, as shown by 5-bromo-2'deoxyuridine (BrdU)/neuronal specific nuclear protein (NeuN) immunostaining in the dentate gyrus. However, in some animals, the pyramidal cell layer was dispersed in the CA3 region. From our previous results with the same model, the hypothesis of alterations of neurogenesis at prior stages of development is worth considering, but is probably not the only one. Therefore, further investigations are needed to correlate cerebral dysfunction and its underlying mechanistic pathways.

Domestic uranium exploration activities

International Nuclear Information System (INIS)

Chenoweth, W.L.

1980-01-01

Uranium exploration in the United States reached its alltime high in 1978 when the chief exploration indicator, surface drilling, totaled 47 million feet. In 1979, however, total drilling declined to 41 million feet, and during the first 8 months of 1980 the trend continued, as surface drilling was 27% less than for the same period in 1979. The total drilling for 1980 now is expected to be below 30 million feet, far less than the 39.4 million feet planned by industry at the beginning of the year. Falling uranium prices, the uncertainties of future uranium demand, rising costs, and the possibility of stiff foreign competition are the prime causes for the current reduction in domestic uranium exploration. Uranium exploration in the United States continues to be concentrated in the vicinity of major producing areas such as the San Juan Basin, Wyoming Basins, Texas Coastal Plain, Paradox Basin, and northeastern Washington, and in areas of recent discoveries including the Henry Mountains, Utah, the McDermitt caldera in Nevada and Oregon, and central Colorado. The distributions, by location, of total surface drilling for 1979 and the first half of 1980 are presented

Consideration of epigenetic responses at organisms chronically exposed to low levels of radioactive substances

International Nuclear Information System (INIS)

Gombeau, Kevin

2015-01-01

This work integrates within the general framework of the European program COMET (7. Framework Programme EURATOM) and aims to assess the epigenetic responses, and particularly DNA methylation, during chronic exposure to low levels of radioactive materials within two particularly representative contexts of radioecological issues (i.e. uranium mining area and Fukushima post-accidental context). During a first experiment, zebra fish (Danio rerio) were exposed in laboratory controlled conditions to environmentally relevant concentrations of depleted uranium: 2 and 20 μg L"-"1. This experiment allowed an impact on the genomic DNA methylation to be demonstrated, mainly in exposed males, which increased with the duration and level of exposure. In a second experiment, we observed an impact on DNA methylation patterns in the progeny of exposed parents, as well as a perturbation of transcriptomics (i.e. epigenetic processes, DNA damage signaling and repair pathways, embryogenesis) and histological damage in larvae skeletal muscle from exposed parents. The methods developed were applied to the second context focusing on the study of biological effects induced by radionuclides emitted following the Fukushima Daiichi nuclear power plant accident. The analyses performed on the Japanese tree frog (Hyla japonica) revealed a positive correlation between the total dose of radiation absorbed by these frogs (correlated to "1"3"7Cs accumulation), hyper-methylation of genomic DNA as well as increasing damage to mitochondrial DNA. This work highlighted the sensitivity of epigenetic responses in different biological models exposed to low levels of radionuclides. Additionally, these epigenetic modifications are stable over the time and involved in the transfer of the parental toxicity of depleted uranium. As such, the epigenetic marks could be used to further characterize adaptation mechanisms and potential trans-generational effects induced by radionuclides. (author)

Aftermath of Uranium Ore Processing on Floodplains: Lasting Effects of Uranium on Soil and Microbes

Science.gov (United States)

Tang, H.; Boye, K.; Bargar, J.; Fendorf, S. E.

2016-12-01

A former uranium ore processing site located between the Wind River and the Little Wind River near the city of Riverton, Wyoming, has generated a uranium plume in the groundwater within the floodplain. Uranium is toxic and poses a threat to human health. Thus, controlling and containing the spread of uranium will benefit the human population. The primary source of uranium was removed from the processing site, but a uranium plume still exists in the groundwater. Uranium in its reduced form is relatively insoluble in water and therefore is retained in organic rich, anoxic layers in the subsurface. However, with the aid of microbes uranium becomes soluble in water which could expose people and the environment to this toxin, if it enters the groundwater and ultimately the river. In order to better understand the mechanisms controlling uranium behavior in the floodplains, we examined sediments from three sediment cores (soil surface to aquifer). We determined the soil elemental concentrations and measured microbial activity through the use of several instruments (e.g. Elemental Analyzer, X-ray Fluorescence, MicroResp System). Through the data collected, we aim to obtain a better understanding of how the interaction of geochemical factors and microbial metabolism affect uranium mobility. This knowledge will inform models used to predict uranium behavior in response to land use or climate change in floodplain environments.

Determination of total and isotopic uranium by inductively coupled plasma-mass spectrometry at the Fernald Environmental Management Project

International Nuclear Information System (INIS)

Miller, F.L.; Bolin, R.N.; Feller, M.T.; Danahy, R.J.

1995-01-01

At the Fernald Environmental Management Project (FEMP) in southwestern Ohio, ICP-mass spectrometry (ICP-MS), with sample introduction by peristaltic pumping, is used to determine total and isotopic uranium (U-234, U-235, U-236 and U-238) in soil samples. These analyses are conducted in support of the environmental cleanup of the FEMP site. Various aspects of the sample preparation and instrumental analysis will be discussed. Initial sample preparation consists of oven drying to determine moisture content, and grinding and rolling to homogenize the sample. This is followed by a nitric/hydrofluoric acid digestion to bring the uranium in the sample into solution. Bismuth is added to the sample prior to digestion to monitor for losses. The total uranium (U-238) content of this solution and the U 235 /U 238 ratio are measured on the first pass through the ICP-MS. To determine the concentration of the less abundant U 234 and U 236 isotopes, the digestate is further concentrated by using Eichrom TRU-Spec extraction columns before the second pass through the ICP-MS. Quality controls for both the sample preparation and instrumental protocols will also be discussed. Finally, an explanation of the calculations used to report the data in either weight percent or activity units will be given

Radiological hazards to uranium miners

International Nuclear Information System (INIS)

1990-05-01

The purpose of the present document is to review and assess the occupational hazards to uranium miners in Canada. Amendments to regulations set the maximum permissible dose to uranium miners at 50 mSv per year. Uranium miners are exposed to radon and thoron progeny, external gamma radiation and long-lived alpha-emitting radionuclides in dust. The best estimate for the lifetime risk of inhaled radon progeny is about 3 x 10 -4 lung cancers per WLM for the average miner, with a range of uncertainty from about 1 -6 x 10 -4 per WLM. This central value is nearly twice as high as that recommended by the ICRP in 1981. The probability of serious biological consequences following exposure to external gamma rays is currently under review but is expected to be in the range of 3 - 6 x 10 -2 Sv -1 . Dosimetric calculations indicate that the stochastic risks per WLM of thoron progeny are about one-third of those for radon progeny. The annual limits on intake of inhaled ore dusts recommended by the ICRP are probably too low by at least a factor of two for the type of ore and dust normally encountered in underground uranium mines in Ontario; this is due in part to the fact that the average diameter of these dusts is five times greater than the value used by the ICRP. Radiological exposures of uranium miners in Canada were reviewed. The biological impact of these exposures were compared with those of conventional accidents on the basis of the years of normal life expectancy that are lost or seriously impaired due to occupational hazards. The objectives in considering all occupational risks are to reduce the total risk from all causes and to use funds spent for health protection as effectively as possible

Bioaccumulation and biological effects in the earthworm Eisenia fetida exposed to natural and depleted uranium

Energy Technology Data Exchange (ETDEWEB)

Giovanetti, Anna, E-mail: anna.giovanetti@enea.i [ENEA, Institute of Radiation Protection, CR Casaccia Via Anguillarese 301, 00123 Rome (Italy); Fesenko, Sergey [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria); Cozzella, Maria L. [ENEA, National Institute for Metrology of Ionizing Radiation, CR Casaccia Via Anguillarese 301, 00123 Rome (Italy); Asencio, Lisbet D. [Centro de Estudios Ambientales, Carretera a Castillo de Jagua, CP. 59350 C. Nuclear, Cienfuegos (Cuba); Sansone, Umberto [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria)

2010-06-15

The accumulations of both natural (U) and depleted (DU) uranium in the earthworms (Eisenia fetida) were studied to evaluate corresponding biological effects. Concentrations of metals in the experimental soil ranged from 1.86 to 600 mg kg{sup -1}. Five biological endpoints: mortality, animals' weight increasing, lysosomal membrane stability by measuring the neutral red retention time (the NRRT), histological changes and genetic effects (Comet assay) were used to evaluate biological effects in the earthworms after 7 and 28 days of exposure. No effects have been observed in terms of mortality or weight reduction. Cytotoxic and genetic effects were identified at quite low U concentrations. For some of these endpoints, in particular for genetic effects, the dose (U concentration)-effect relationships have been found to be non-linear. The results have also shown a statistically significant higher level of impact on the earthworms exposed to natural U compared to depleted U.

Bioaccumulation and biological effects in the earthworm Eisenia fetida exposed to natural and depleted uranium

International Nuclear Information System (INIS)

Giovanetti, Anna; Fesenko, Sergey; Cozzella, Maria L.; Asencio, Lisbet D.; Sansone, Umberto

2010-01-01

The accumulations of both natural (U) and depleted (DU) uranium in the earthworms (Eisenia fetida) were studied to evaluate corresponding biological effects. Concentrations of metals in the experimental soil ranged from 1.86 to 600 mg kg -1 . Five biological endpoints: mortality, animals' weight increasing, lysosomal membrane stability by measuring the neutral red retention time (the NRRT), histological changes and genetic effects (Comet assay) were used to evaluate biological effects in the earthworms after 7 and 28 days of exposure. No effects have been observed in terms of mortality or weight reduction. Cytotoxic and genetic effects were identified at quite low U concentrations. For some of these endpoints, in particular for genetic effects, the dose (U concentration)-effect relationships have been found to be non-linear. The results have also shown a statistically significant higher level of impact on the earthworms exposed to natural U compared to depleted U.

Uranium deposits in Africa

International Nuclear Information System (INIS)

Wilpolt, R.H.; Simov, S.D.

1979-01-01

Africa is not only known for its spectacular diamond, gold, copper, chromium, platinum and phosphorus deposits but also for its uranium deposits. At least two uranium provinces can be distinguished - the southern, with the equatorial sub-province; and the south Saharan province. Uranium deposits are distributed either in cratons or in mobile belts, the first of sandstone and quartz-pebble conglomerate type, while those located in mobile belts are predominantly of vein and similar (disseminated) type. Uranium deposits occur within Precambrian rocks or in younger platform sediments, but close to the exposed Precambrian basement. The Proterozoic host rocks consist of sediments, metamorphics or granitoids. In contrast to Phanerozoic continental uranium-bearing sediments, those in the Precambrian are in marginal marine facies but they do contain organic material. The geology of Africa is briefly reviewed with the emphasis on those features which might control the distribution of uranium. The evolution of the African Platform is considered as a progressive reduction of its craton area which has been affected by three major Precambrian tectonic events. A short survey on the geology of known uranium deposits is made. However, some deposits and occurrences for which little published material is available are treated in more detail. (author)

Maximum permissible concentrations of uranium in air

CERN Document Server

Adams, N

1973-01-01

The retention of uranium by bone and kidney has been re-evaluated taking account of recently published data for a man who had been occupationally exposed to natural uranium aerosols and for adults who had ingested uranium at the normal dietary levels. For life-time occupational exposure to uranium aerosols the new retention functions yield a greater retention in bone and a smaller retention in kidney than the earlier ones, which were based on acute intakes of uranium by terminal patients. Hence bone replaces kidney as the critical organ. The (MPC) sub a for uranium 238 on radiological considerations using the current (1959) ICRP lung model for the new retention functions is slightly smaller than for earlier functions but the (MPC) sub a determined by chemical toxicity remains the most restrictive.

French experience with Uranium compounds: conclusions of medical working group

International Nuclear Information System (INIS)

Berard, P.; Mazeyrat, C.; Auriol, B.; Montegue, A.; Estrabaud, M.; Grappin, L.; Giraud, J.M.

2002-01-01

The authors who represent several organisations and industrial firms, present observations conducted for some thirty years in France, including routine monitoring or special measurements following contamination by uranium compounds. They propose recommendations for radio toxicological monitoring of workers exposed to industrial uranium compounds and they comment on urine and faecal collections in relation to specific exposures. Our working group, set up by the CEA Medical Adviser in 1975, consists of French specialists in uranium radio toxicology. Their role is to propose recommendations for the monitoring of working conditions and exposed workers. The different plants process chemically and metallurgically, and machine large quantities of uranium with various 235U enrichments. Radio toxicological monitoring of workers exposed to uranium compounds requires examinations prescribed according to the kind of product manipulated and the industrial risk of the workplace. The range of examinations that are useful for this kind of monitoring includes lung monitoring, urine analyses and faecal sampling. The authors present the frequency of the monitoring for routine or special conditions according to industrial exposure, time and duration of collection of excreta (urine and faeces), the necessity of a work break, precautions for preservation of the samples and the ways in interpreting excretion analysis according to natural food intakes

The composition and character of oxycarbide phase in uranium metal

International Nuclear Information System (INIS)

Liu Kezhao; Lai Xinchun; Yu Yong; Ni Ranfu

1999-08-01

The oxide layer of uranium metal formed by vacuum heating were examined with X-ray photoelectron spectroscopy (XPS) and Auger Electron Spectroscopy (AES). XPS results indicated that the air-exposed surface of the oxide layer were mainly consisted of UO 2 and free carbon. After the air-exposed surface were removed by low energy argon ion sputtering, C1s spectra shifted from 284.8 eV to 281.8 eV, indicating the existence of carbide phase. AES results of C(KVV) Auger transitions confirmed this result. Resolved and fitted using a combination of Gaussian and Lorentzian peak shape, U4f 7/2 spectra showed that three uranium chemical states existed in the layer, there were uranium dioxide, uranium carbide (or oxycarbide, UC x O 1-x ) and uranium metal phase. Calculated the AES data by relatively sensitive factor, the composition of oxycarbide was given as UC 0.41+-0.04 O 0.62+-0.01

The behaviour of uranium metal in hydrogen atmospheres

International Nuclear Information System (INIS)

Allen, G.C.; Stevens, J.C.H.

1988-01-01

The reaction between commercial H 2 and uranium metal leads to the formation of UO 2 due to traces of water vapour or oxygen. When extremely pure H 2 is used uranium hydride may be formed but, even with 99.9999% H 2 , uranium dioxide forms preferentially. The present work identifies the presence of UH 3 in the X-ray photoelectron spectrum of a uranium sample which has been exposed to ca. 10 10 L† H 2 at ca. 200 0 C. This spectrum indicates that the hydride possesses a high degree of covalency, since the oxidation state of uranium in UH 3 appears to be ca. 1.4. (author)

Uranium in Canada

International Nuclear Information System (INIS)

1987-09-01

Canadian uranium exploration and development efforts in 1985 and 1986 resulted in a significant increase in estimates of measured uranium resources. New discoveries have more than made up for production during 1985 and 1986, and for the elimination of some resources from the overall estimates, due to the sustained upward pressure on production costs and the stagnation of uranium prices in real terms. Canada possesses a large portion of the world's uranium resources that are of current economic interest and remains the major focus of inter-national uranium exploration activity. Expenditures for uranium exploration in Canada in 1985 and 1986 were $32 million and $33 million, respectively. Although much lower than the $130 million total reported for 1979, expenditures for 1987 are forecast to increase. Exploration and surface development drilling in 1985 and 1986 were reported to be 183 000 m and 165σ2 000 m, respectively, 85 per cent of which was in Saskatchewan. Canada has maintained its position as the world's leading producer and exporter of uranium. By the year 2000, Canada's annual uranium requirements will be about 2 100 tU. Canada's known uranium resources are more than sufficient to meet the 30-year fuel requirements of those reactors in Canada that are either in operation now or expected to be in service by the late 1990s. A substantial portion of Canada's identified uranium resources is thus surplus to Canadian needs and available for export. Annual sales currently approach $1 billion, of which exports account for 85 per cent. Forward domestic and export contract commitments totalled 73 000 tU and 62 000 tU, respectively, as of early 1987

Epidemiological study of workers at risk of internal exposure to uranium

International Nuclear Information System (INIS)

Guseva Canu, I.

2008-09-01

This work is a pilot-study among nuclear fuel cycle workers potentially exposed to alpha radiation. Internal exposure from inhalation of uranium compounds during uranium conversion and enrichment operations was estimated at the AREVA NC Pierrelatte plant. A plant specific semi-quantitative job exposure matrix (JEM) was elaborated for 2709 workers employed at this plant between 1960 and 2006. The JEM has permitted to estimate the exposure to uranium and 16 other categories of pollutants and to calculate individual cumulative exposure score. Numerous correlations were detected between uranium compounds exposure and exposure to other pollutants, such as asbestos, ceramic refractive fibers, TCE and so on. 1968-2005 mortality follow-up showed an increasing risk of mortality from pleural cancer, rectal cancer and lymphoma on the basis of national mortality rates. Analyses of association between cancer mortality and uranium exposure suggested an increase in mortality due to lung cancer among workers exposed to slowly soluble uranium compounds derived from natural and reprocessed uranium. However these results are not statistically significant and based on a small number of observed deaths. These results are concordant with previously reported results from other cohorts of workers potentially exposed to uranium. Experimental studies of biokinetic and action mechanism of slowly soluble uranium oxides bear the biological plausibility of the observed results. Influence of bias was reduced by taking into account of possible confounding including co-exposure to other carcinogenic pollutants and tobacco consumption in the study. Nevertheless, at this stage statistical power of analyses is too limited to obtain more conclusive results. This pilot study shows the interest and feasibility of an epidemiological investigation among workers at risk of internal exposure to uranium and other alpha emitters at the national level. It demonstrates the importance of exposure assessment for

Assessment of the total uranium concentration in surface and underground water samples from the Caetite region, Bahia, Brazil

International Nuclear Information System (INIS)

Silva, Julia Grasiela Batista; Geraldo, Luiz Paulo; Yamazaki, Ione Makiko

2011-01-01

At the region of Caetite, BA, it is located the largest uranium mine in exploration at present days in Brazil. During the uranium extraction process, it may be having an environmental contamination by this heavy metal due to rain water and other natural transport mechanism, with potential exposition risk to the local population. The aim of this work was to investigate the total uranium concentration in surface and underground water samples collected at the Caetite region, using the nuclear track registration technique (SSNTD) in a polycarbonate plastic. A 100 mL volume of water samples were initially treated in 10 mL of HNO 3 (PA) and concentrated by evaporation at a temperature around 80 deg C. The resulting residue was diluted to a total volume of 25 mL without pass it to a filter. About 10 μL of this solution was deposited on the plastic detector surface (around 1.0 cm 2 area) together with 5 μL of a Cyastat detergent solution (5%) and evaporated under an infrared lamp. All the resulting deposits of non volatile constituents were irradiated, together with a uranium standard sample, at the IPEN-IEA-R1 (3.5 MW) nuclear reactor for approximately 3 min. After irradiations, chemical etching of the plastic detectors was carried out at 60 deg C, for 65 min. in a NaOH (6N) solution. The fission tracks were counted scanning all the deposit area of the polycarbonate plastic detector with a system consisting of an optical microscope together with a video camera and TV monitor. The average values of uranium concentrations obtained in this work ranged from (0.95±0.19) μg.L -1 to (25.60±3.3) μg.L -1 . These results were compared to values reported in the literature for water samples from other regions and discussed in terms of safe limits recommended by WHO -World Health Organization and CONAMA - Conselho Nacional do Meio Ambiente. (author)

Assessment of the total uranium concentration in surface and underground water samples from the Caetite region, Bahia, Brazil

Energy Technology Data Exchange (ETDEWEB)

Silva, Julia Grasiela Batista; Geraldo, Luiz Paulo [Centro Universitario da Fundacao Educacional de Barretos (UNIFEB), (SP) (Brazil); Yamazaki, Ione Makiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

At the region of Caetite, BA, it is located the largest uranium mine in exploration at present days in Brazil. During the uranium extraction process, it may be having an environmental contamination by this heavy metal due to rain water and other natural transport mechanism, with potential exposition risk to the local population. The aim of this work was to investigate the total uranium concentration in surface and underground water samples collected at the Caetite region, using the nuclear track registration technique (SSNTD) in a polycarbonate plastic. A 100 mL volume of water samples were initially treated in 10 mL of HNO{sub 3} (PA) and concentrated by evaporation at a temperature around 80 deg C. The resulting residue was diluted to a total volume of 25 mL without pass it to a filter. About 10 {mu}L of this solution was deposited on the plastic detector surface (around 1.0 cm{sup 2} area) together with 5 {mu}L of a Cyastat detergent solution (5%) and evaporated under an infrared lamp. All the resulting deposits of non volatile constituents were irradiated, together with a uranium standard sample, at the IPEN-IEA-R1 (3.5 MW) nuclear reactor for approximately 3 min. After irradiations, chemical etching of the plastic detectors was carried out at 60 deg C, for 65 min. in a NaOH (6N) solution. The fission tracks were counted scanning all the deposit area of the polycarbonate plastic detector with a system consisting of an optical microscope together with a video camera and TV monitor. The average values of uranium concentrations obtained in this work ranged from (0.95{+-}0.19) {mu}g.L{sup -1} to (25.60{+-}3.3) {mu}g.L{sup -1}. These results were compared to values reported in the literature for water samples from other regions and discussed in terms of safe limits recommended by WHO -World Health Organization and CONAMA - Conselho Nacional do Meio Ambiente. (author)

Internal contamination by natural uranium: monitoring by analysis of urine of individuals exposed by occupational inhalation

International Nuclear Information System (INIS)

Ramalho, A.T.

1982-01-01

Urine samples from men working at Usina Santo Amaro (USAM - State of Sao Paulo), a monazite refinery, were analysed for uranium concentration, using fluorometric analysis and alpha spectrometry. All samples analysed presented uranium concentration below the lower limit of detection. Theoretical values were calculated for uranium concentration in urine samples from workers at the annual limit of intake (ALI) for inhalation of natural uranium, recommended in Publication 30 of the International Commission on Radiological Protection (ICRP, 1979). The two different methods used for analysis of natural uranium concentration in the urine samples were compared: fluorimetry and alpha spectrometry. (author)

Influence of uranium hydride oxidation on uranium metal behaviour

International Nuclear Information System (INIS)

Patel, N.; Hambley, D.; Clarke, S.A.; Simpson, K.

2013-01-01

This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

Influence of uranium hydride oxidation on uranium metal behaviour

Energy Technology Data Exchange (ETDEWEB)

Patel, N.; Hambley, D. [National Nuclear Laboratory (United Kingdom); Clarke, S.A. [Sellafield Ltd (United Kingdom); Simpson, K.

2013-07-01

This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

The fluorimetry for control of internal contamination of exposed workers to natural and enriched uranium

International Nuclear Information System (INIS)

Gaburo, J.C.; Todo, A.S.; Sordi, G.M.A.A.

2000-01-01

This study is a part of bioassay program revision applied to the uranium processing plants at IPEN-CNEN/SP. The workers of these facilities handle both natural uranium and uranium compounds with different isotopic composition which could reach up to 20% in 235 U. The most commonly employed techniques for the determination of uranium in urine at IPEN are fluorimetry and alpha spectrometry with detection limit of 1.0 mgL-1. and 1,0 mBqL-1 , respectively. Based in advantages and disadvantages of each technique it is very important to identify the workers groups that should be submitted for these analysis. In this report a limiting value of uranium concentration in urine, mgL-1, obtained by fluorimetry is proposed. All the results greater than these limiting value indicate the necessity to carry out a additional measurement by alpha spectroscopy. The uranium mass that result in a pre-determined limit committed effective dose is function of isotopic composition. Consequently, the predicted value of the measured of urinary excretion is function of isotopic composition also and depends of absorption characteristics when inhaled and of the monitoring interval considered. In this report the uranium concentration values for reference levels and limits doses are determined. Based on these results the procedures to use the fluorimetry or both fluorimetry and alpha-spectrometry were adopted. (author)

Exposure to uranium and cancer risk: a review of epidemiological studies; Exposition a l'uranium et risque de cancer: une revue des etudes epidemiologiques

Energy Technology Data Exchange (ETDEWEB)

Tirmarche, M.; Baysson, H.; Telle-Lamberton, M. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Service de Radiobiologie et d' Epidemiologie, Dir. de la Radioprotection de l' Homme, 92 - Clamart (France)

2004-02-01

Objective: At the end of 2000, certain diseases including leukemia were reported among soldiers who participated in the Balkan and in the Gulf wars. Depleted uranium used during these conflicts was considered as a possible cause. Its radiotoxicity is close to that of natural uranium. This paper reviews the epidemiological knowledge of uranium, the means of exposure and the associated risk of cancer. Methods: The only available epidemiological data concerns nuclear workers exposed to uranium. A review of the international literature is proposed by distinguishing between uranium miners and other workers of the nuclear industry. French studies are described in details. Results: In ionizing radiation epidemiology, contamination by uranium is often cited as a risk factor, but the dose-effect relationship is rarely studied. Retrospective assessment of individual exposure is generally insufficient. Moreover, it is difficult to distinguish between uranium radiotoxicity, its chemical toxicity and the radiotoxicity of its progeny. A causal relation between lung cancer and radon exposure, a gas derived from the decay of uranium, has been demonstrated in epidemiological studies of miners. Among other nuclear workers exposed to uranium, there is a mortality deficit from all causes (healthy worker effect). No cancer site appears systematically in excess compared to the national population; very few studies describe a dose-response relationship. Conclusion: Only studies with a precise reconstruction of doses and sufficient numbers of workers will allow a better assessment of risks associated with uranium exposure at levels encountered in industry or during conflicts using depleted uranium weapons. (author)

Basis for the ICRP's age-specific biokinetic model for uranium

International Nuclear Information System (INIS)

Leggett, R.W.

1994-01-01

In an effort motivated largely by the Chernobyl nuclear accident, the International Commission on Radiological Protection (ICRP) is developing age-specific biokinetic models and dose coefficients for environmentally important radionuclides. This paper describes the ICRP's age-specific biokinetic model for uranium. The model is constructed within a physiologically based framework originally developed for application to the alkaline earth elements but sufficiently general to apply to the larger class of bone-volume-seeking elements. Transfer rates for a reference adult are based mainly on: (1) measurements of uranium in blood and excreta of several human subjects who were intravenously injected with uranium; (2) postmortem measurements of uranium in tissues of some of those subjects; (3) postmortem measurements of uranium in tissues of occupationally and non-occupationally exposed subjects; (4) data on baboons, dogs, and smaller laboratory animals exposed to uranium for experimental purposes; and (5) consideration of the physiological processes thought to control retention and translocation of uranium in the body. Transfer rates for the adult are extended to children by application of a set of generic assumptions applied by the ICRP to calcium-like elements. These assumptions were derived mainly from observations of the age-specific biokinetics of the alkaline earth elements and lead in humans and laboratory animals but are consistent with available age-specific biokinetic data on uranium. 82 refs., 17 figs., 8 tabs

Radiation protection program applied to occupationally exposed individuals at the IPEN/CNEN-SP pilot plant in the 1980s for natural uranium compounds

International Nuclear Information System (INIS)

Silva, Teresinha de Moraes da; Sordi, Gian Maria A.A.; Vasques, Francisco Mário Feijó

2017-01-01

The work evidences the chemical processing of natural uranium from the yellowcake phase to the production of UF 6 natural uranium hexafluoride, a process carried out at the IPEN/CNEN-SP pilot plant. Radiation protection management was intended to monitor occupationally exposed individuals - IOEs, the workplace and the environment. An individual monitoring program for IOEs was developed for both external irradiation and incorporation of radioactive material. The IOEs were monitored externally with film-type dosimeters and the in vitro method was applied internally for urine analysis. For the workplace the monitoring program for equipment and floors was developed, determining the exposure rate from the process equipment, surface contamination expressed in Bq.cm -2 in equipment and floors, complemented by the air monitoring program both for the worker as well as for the workplace. Cellulose filters with aerodynamic diameter of 0.3 micron to 8.0 micron were used

Efficient isotope ratio analysis of uranium particles in swipe samples by total-reflection x-ray fluorescence spectrometry and secondary ion mass spectrometry

International Nuclear Information System (INIS)

Esaka, Fumitaka; Watanabe, Kazuo; Fukuyama, Hiroyasu; Onodera, Takashi; Esaka, Konomi T.; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu

2004-01-01

A new particle recovery method and a sensitive screening method were developed for subsequent isotope ratio analysis of uranium particles in safeguards swipe samples. The particles in the swipe sample were recovered onto a carrier by means of vacuum suction-impact collection method. When grease coating was applied to the carrier, the recovery efficiency was improved to 48±9%, which is superior to that of conventionally-used ultrasoneration method. Prior to isotope ratio analysis with secondary ion mass spectrometry (SIMS), total reflection X-ray fluorescence spectrometry (TXRF) was applied to screen the sample for the presence of uranium particles. By the use of Si carriers in TXRF analysis, the detection limit of 22 pg was achieved for uranium. By combining these methods with SIMS, the isotope ratios of 235 U/ 238 U for individual uranium particles were efficiently determined. (author)

Uranium hydrogeochemical and stream sediment reconnaissance of the Dalhart NTMS quadrangle, New Mexico/Texas/Oklahoma, including concentrations of forty-two additional elements

International Nuclear Information System (INIS)

Morgan, T.L.

1980-08-01

Totals of 1583 water samples and 503 sediment samples were collected from 2028 locations within the 20 000-km 2 area of the quadrangle at an average density of one location per 9.86 km 2 . Water samples were collected from wells, springs, and streams and were analyzed for uranium. Sediment samples were collected from streams and springs and were analyzed for uranium, thorium, and 41 additional elements. All field and analytical data are listed in the appendixes of this report. Discussion is limited to anomalous samples, which are considered to be those containing over 20 ppB uranium for waters and over 5 ppM uranium for sediments. Uranium concentrations in water samples range from below the detection limit of 0.2 ppB to 1457.65 ppB and average 7.41 ppB. Most of the seventy anomalous water samples (4.4% of all water samples) are grouped spatially into five clusters or areas of interest. Samples in three of the clusters were collected along the north edge of the quadrangle where Mesozoic strata are exposed. The other two clusters are from the central and southern portions where the Quaternary Ogallala formation is exposed. Sediment samples from the quadrangle have uranium concentrations that range from 0.90 ppM to 27.20 ppM and average 3.27 ppM. Fourteen samples (2.8% of all sediment samples) contain over 5 ppM uranium and are considered anomalous. The five samples with the highest concentrations occur where downcutting streams expose Cretaceous units beneath the Quaternary surficial deposits. The remaining anomalous sediment samples were collected from scattered locations and do not indicate any single formation or unit as a potential source for the anomalous concentrations

Investigating and comparing uranium and gamma radiation induced effects on photosynthetic parameters for Arabidopsis thaliana

Energy Technology Data Exchange (ETDEWEB)

Vanhoudt, Nathalie; Horemans, Nele; Saenen, Eline; Biermans, Geert; Nauts, Robin; Wannijn, Jean; Van Hees, May; Vandenhove, Hildegarde [Belgian Nuclear Research Centre (SCK.CEN), Biosphere Impact Studies, 2400, Mol (Belgium)

2014-07-01

As the environment is inevitably exposed to radionuclides and ionizing radiation from natural and anthropogenic sources, it is important to study the effects induced by these stressors on plants. In addition, it is already known that photosynthesis can be affected under various metal exposure situations. The objective of this research is to compare uranium induced effects with gamma radiation induced effects on photosynthetic parameters in Arabidopsis thaliana. First, 18-day-old seedlings were exposed to 50 μM uranium during 4 days. Second, 14-day-old seedlings were exposed to gamma radiation for 7 days to a total dose of 6.7 Gy. By using chlorophyll fluorescence measurements, the photosynthetic performance was assessed. Based on the data obtained during the measurement of induction curves, parameters providing information on the photosynthetic efficiency and heat dissipation can be calculated. For uranium exposed leaves, it was observed that the potential photosynthetic efficiency (measured as Fv/Fm) remained maximal while the effective efficiency of photosystem II (φPSII), which is a measure for the proportion of light absorbed by PSII used in photochemistry, even increased. The increase of φPSII could be related to a decrease in non-photochemical quenching (NPQ), which reflects the protective mechanism against excess light intensity by converting energy into heat, but no alterations in non-regulated energy dissipation (NO). A high NO value would indicate the inefficiency of photochemistry and heat conversion and the plant's inability to regulate the radiation energy. In plants exposed to uranium, NO levels were similar to the control. Under gamma irradiation, the capacity of PSII remained intact and plants started optimizing their photosynthetic process by increasing φPSII and decreasing NPQ. When comparing the NPQ kinetic responses of gamma radiation and uranium exposure, a remarkable difference can be highlighted. While gamma radiation exposure

Ultrastructural localization of uranium biosorption in Penicillium digitatum by stem x-ray microanalysis

International Nuclear Information System (INIS)

Galun, M.; Galun, E.

1987-01-01

When Penicillium digitatum Saccardo cultures are exposed to aqueous solutions containing soluble uranium salts, considerable amounts of this element are accumulated in the fungal mycelium. The accumulated uranium is retained after thorough rinsing with distilled water but is removed by alkali carbonate solutions. Analysis of thick sections (0.5 μm) of the fungal hyphae with TEM, after incubation in UO 2 Cl 2 solutions of varying concentrations under both light and dark conditions, revealed conspicuous crystal-like deposits in UO 2 Cl 2 -exposed hyphae, but none in the control hyphae. Thick sections were necessary for crystal visualization. Using energy-dispersive X-ray analysis, uranium was detected as the only heavy element in these crystals. Uranium crystal biosorption was localized on the outside surface of the hyphal cell wall (following short exposures to relatively low uranium concentrations) or inside the cell wall (following long exposure to relatively high uranium concentrations). In some cases, crystal-like deposits of uranium salts were located on the outside surface as well as inside the cell. (author)

Uranium

International Nuclear Information System (INIS)

Anon.

1983-01-01

Recent decisions by the Australian Government will ensure a significant expansion of the uranium industry. Development at Roxby Downs may proceed and Ranger may fulfil two new contracts but the decision specifies that apart from Roxby Downs, no new mines should be approved. The ACTU maintains an anti-uranium policy but reaction to the decision from the trade union movement has been muted. The Australian Science and Technology Council (ASTEC) has been asked by the Government to conduct an inquiry into a number of issues relating to Australia's role in the nuclear fuel cycle. The inquiry will examine in particular Australia's nuclear safeguards arrangements and the adequacy of existing waste management technology. In two additional decisions the Government has dissociated itself from a study into the feasibility of establishing an enrichment operation and has abolished the Uranium Advisory Council. Although Australian reserves account for 20% of the total in the Western World, Australia accounts for a relatively minor proportion of the world's uranium production

Exposure to uranium and cancer risk: a review of epidemiological studies

International Nuclear Information System (INIS)

Tirmarche, M.; Baysson, H.; Telle-Lamberton, M.

2004-01-01

Objective: At the end of 2000, certain diseases including leukemia were reported among soldiers who participated in the Balkan and in the Gulf wars. Depleted uranium used during these conflicts was considered as a possible cause. Its radiotoxicity is close to that of natural uranium. This paper reviews the epidemiological knowledge of uranium, the means of exposure and the associated risk of cancer. Methods: The only available epidemiological data concerns nuclear workers exposed to uranium. A review of the international literature is proposed by distinguishing between uranium miners and other workers of the nuclear industry. French studies are described in details. Results: In ionizing radiation epidemiology, contamination by uranium is often cited as a risk factor, but the dose-effect relationship is rarely studied. Retrospective assessment of individual exposure is generally insufficient. Moreover, it is difficult to distinguish between uranium radiotoxicity, its chemical toxicity and the radiotoxicity of its progeny. A causal relation between lung cancer and radon exposure, a gas derived from the decay of uranium, has been demonstrated in epidemiological studies of miners. Among other nuclear workers exposed to uranium, there is a mortality deficit from all causes (healthy worker effect). No cancer site appears systematically in excess compared to the national population; very few studies describe a dose-response relationship. Conclusion: Only studies with a precise reconstruction of doses and sufficient numbers of workers will allow a better assessment of risks associated with uranium exposure at levels encountered in industry or during conflicts using depleted uranium weapons. (author)

Examination of health status of population from Uranium contaminated regions

International Nuclear Information System (INIS)

Milacic, S.; Jovicic, D.; Pantelic, G.; Kovacevic, R.; Pavlovic, M.; Tanaskovic, I.

2002-01-01

Uranium is widely distributed in the natural environment: in the soil, air and food. And thus all people on the planet inhale or ingest small quantities of uranium every day. However, depleted uranium (DU) is industrial product. It is used in medicine, aviation, astronomy, oil exploitation, as well as for military purposes for penetrating ammunition. America is not the only country that applies depleted uranium ammunition. It is a part of the military arsenal in France, England, Turkey, Israel, Russia, Saudi Arabia, Pakistan and Thailand. Depleted uranium is toxic for both humans and animals for two basic reasons: as a heavy metal, it has toxic chemical effects, and as an alpha-emitter, it also has radioactive effects. Although it is considered less radioactive than natural uranium, its toxicity is high due to high LET (linear energetic transfer) irradiation, tissue deposition (bones, kidneys, blood, lungs) and elimination time (5000 days). Radiation limit above which adverse health effects are initiated (radiation carcinogenic risk), depends on the quantity and contamination time (how much and how long), including also other factors, such as age, sex, previous health status, exposure to other materials, genetic predisposition and radiosensitivity (lack of indicators), diet and stress. According to ICRP recommendations, carcinogenic risk for the occupationally exposed individuals is minimal if the exposure is limited to the effective dose of 100 mSv for five years and not above 50 in a single year, being five times lower for general population. In average annual effective dose per population, from all sources is below 1mSv, carcinogenic risk will range from 1 per 10 000 to 1 per 100 000, and in occupationally exposed individuals exposed to maximum permitted doses (MPD), the risk of cancer with fatal outcome is below 3 per 100 000). Immediate effects of population exposure to low uranium doses do not result in evident clinical picture. Late consequences include

Determination of uranium isotopes in urine

International Nuclear Information System (INIS)

Lellis, I.R.; Silva, D.V.F.M. Rey; Taddei, M.H.T.

2017-01-01

Variable concentrations of uranium occur naturally in waters, plant products and soils. Small amounts of this element are routinely incorporated by man. Occupationally exposed individuals (IOEs) are subject to the incorporation of higher amounts of uranium into their work routines. The effects on human health resulting from the incorporation of uranium in environmental doses are not very well established and are currently recognized as of little relevance. The incorporation resulting from occupational activities, where higher doses can be found, represents a health risk resulting from chemical damages to the kidneys. Considering that uranium is eliminated from the human body through urine and feces, and that the concentration in the urine can be obtained by means of radiochemical analyzes, this can be considered an efficient indirect method to verify the incorporation of this element. In the work the isotopes of 234 U, 235 U and 238 U were analyzed in urine samples of IOEs and the rate of uranium present in them was verified

Uranium market and resources

International Nuclear Information System (INIS)

Capus, G.; Arnold, Th.

2004-01-01

The controversy about the extend of the uranium resources worldwide is still important, this article sheds some light on this topic. Every 2 years IAEA and NEA (nuclear energy agency) edit an inventory of uranium resources as reported by contributing countries. It appears that about 4.6 millions tons of uranium are available at a recovery cost less than 130 dollars per kg of uranium and a total of 14 millions tons of uranium can be assessed when including all existing or supposed resources. In fact there is enough uranium to sustain a moderate growth of the park of nuclear reactors during next decades and it is highly likely that the volume of uranium resources can allow a more aggressive development of nuclear energy. It is recalled that a broad use of the validated breeder technology can stretch the durability of uranium resources by a factor 50. (A.C.)

Uranium enrichment

International Nuclear Information System (INIS)

1989-01-01

GAO was asked to address several questions concerning a number of proposed uranium enrichment bills introduced during the 100th Congress. The bill would have restructured the Department of Energy's uranium enrichment program as a government corporation to allow it to compete more effectively in the domestic and international markets. Some of GAO's findings discussed are: uranium market experts believe and existing market models show that the proposed DOE purchase of a $750 million of uranium from domestic producers may not significantly increase production because of large producer-held inventories; excess uranium enrichment production capacity exists throughout the world; therefore, foreign producers are expected to compete heavily in the United States throughout the 1990s as utilities' contracts with DOE expire; and according to a 1988 agreement between DOE's Offices of Nuclear Energy and Defense Programs, enrichment decommissioning costs, estimated to total $3.6 billion for planning purposes, will be shared by the commercial enrichment program and the government

Metals other than uranium affected microbial community composition in a historical uranium-mining site.

Science.gov (United States)

Sitte, Jana; Löffler, Sylvia; Burkhardt, Eva-Maria; Goldfarb, Katherine C; Büchel, Georg; Hazen, Terry C; Küsel, Kirsten

2015-12-01

To understand the links between the long-term impact of uranium and other metals on microbial community composition, ground- and surface water-influenced soils varying greatly in uranium and metal concentrations were investigated at the former uranium-mining district in Ronneburg, Germany. A soil-based 16S PhyloChip approach revealed 2358 bacterial and 35 archaeal operational taxonomic units (OTU) within diverse phylogenetic groups with higher OTU numbers than at other uranium-contaminated sites, e.g., at Oak Ridge. Iron- and sulfate-reducing bacteria (FeRB and SRB), which have the potential to attenuate uranium and other metals by the enzymatic and/or abiotic reduction of metal ions, were found at all sites. Although soil concentrations of solid-phase uranium were high, ranging from 5 to 1569 μg·g (dry weight) soil(-1), redundancy analysis (RDA) and forward selection indicated that neither total nor bio-available uranium concentrations contributed significantly to the observed OTU distribution. Instead, microbial community composition appeared to be influenced more by redox potential. Bacterial communities were also influenced by bio-available manganese and total cobalt and cadmium concentrations. Bio-available cadmium impacted FeRB distribution while bio-available manganese and copper as well as solid-phase zinc concentrations in the soil affected SRB composition. Archaeal communities were influenced by the bio-available lead as well as total zinc and cobalt concentrations. These results suggest that (i) microbial richness was not impacted by heavy metals and radionuclides and that (ii) redox potential and secondary metal contaminants had the strongest effect on microbial community composition, as opposed to uranium, the primary source of contamination.

Solubility measurement of uranium in uranium-contaminated soils

International Nuclear Information System (INIS)

Lee, S.Y.; Elless, M.; Hoffman, F.

1993-08-01

A short-term equilibration study involving two uranium-contaminated soils at the Fernald site was conducted as part of the In Situ Remediation Integrated Program. The goal of this study is to predict the behavior of uranium during on-site remediation of these soils. Geochemical modeling was performed on the aqueous species dissolved from these soils following the equilibration study to predict the on-site uranium leaching and transport processes. The soluble levels of total uranium, calcium, magnesium, and carbonate increased continually for the first four weeks. After the first four weeks, these components either reached a steady-state equilibrium or continued linearity throughout the study. Aluminum, potassium, and iron, reached a steady-state concentration within three days. Silica levels approximated the predicted solubility of quartz throughout the study. A much higher level of dissolved uranium was observed in the soil contaminated from spillage of uranium-laden solvents and process effluents than in the soil contaminated from settling of airborne uranium particles ejected from the nearby incinerator. The high levels observed for soluble calcium, magnesium, and bicarbonate are probably the result of magnesium and/or calcium carbonate minerals dissolving in these soils. Geochemical modeling confirms that the uranyl-carbonate complexes are the most stable and dominant in these solutions. The use of carbonate minerals on these soils for erosion control and road construction activities contributes to the leaching of uranium from contaminated soil particles. Dissolved carbonates promote uranium solubility, forming highly mobile anionic species. Mobile uranium species are contaminating the groundwater underlying these soils. The development of a site-specific remediation technology is urgently needed for the FEMP site

Characterization of uranium isotopic abundances in depleted uranium metal assay standard 115

International Nuclear Information System (INIS)

Mathew, K.J.; Singleton, G.L.; Essex, R.M.; Hasozbek, A.; Orlowicz, G.; Soriano, M.

2013-01-01

Certified reference material (CRM) 115, Uranium (Depleted) Metal (Uranium Assay Standard), was analyzed using a TRITON Thermal Ionization Mass Spectrometer to characterize the uranium isotope-amount ratios. The certified 235 U/ 238 U 'major' isotope-amount ratio of 0.0020337 (12) in CRM 115 was determined using the total evaporation (TE) and the modified total evaporation (MTE) analytical techniques. In the MTE method, the total evaporation process is interrupted on a regular basis to allow correction of background from peak tailing, internal calibration of the secondary electron multiplier detector versus the Faraday cups, peak-centering, and ion source re-focusing. For the 'minor' 234 U/ 238 U and 236 U/ 238 U isotope-amount ratio measurements using MTE, precision and accuracy comparable to conventional analyses are achieved, without compromising the quality of the 235 U/ 238 U isotope-amount ratios. Characterized values of the 234 U/ 238 U and 236 U/ 238 U isotope-amount ratios in CRM 115 are 0.000007545 (10) and 0.000032213 (84), respectively. The 233 U/ 238 U isotope-amount ratio in CRM 115 is estimated to be -9 . The homogeneity of the CRM 115 materials is established through the absence of any statistically significant unit-to-unit variation in the uranium isotope-amount ratios. The measurements leading to the certification of uranium isotope-amount ratios are discussed. (author)

Pyrophoricity of uranium in long-term storage environments

International Nuclear Information System (INIS)

Solbrig, C.W.; Krsul, J.R.; Olsen, D.N.

1994-01-01

A corrosion cycle for uranium is postulated which can be used to assess whether a given storage situation might produce fire hazards and/or continual uranium corrosion. A significant reaction rate of uranium and moisture occurs at room temperature which produces uranium oxide and hydrogen. If the hydrogen cannot escape, it will react slowly with uranium to form uranium hydride. The hydride is pyrophoric at room temperature when exposed to air. Either the hydrogen or the hydride can produce a dangerous situation as demonstrated by two different incidents described here. Long-term corrosion will occur even if the normal precautions are taken as is demonstrated by the long-term storage of stainless steel clad uranium fuel plates. The major initiator of these problems is attributed to any moisture condensed on the metal or any brought in by the cover gas. The postulated corrosion cycle is used to suggest ways to circumvent these problems

World War II uranium hexafluoride inhalation event with pulmonary implications for today

International Nuclear Information System (INIS)

Moore, R.H.; Kathren, R.L.

1985-01-01

Two individuals were exposed to massive quantities of airborne uranium hexafluoride (UF6) and its hydrolysis products following a World War II equipment rupture. An excretion pattern for uranium exhibited by these patients is, in light of current knowledge, anomalous. The possible role of pulmonary edema is discussed. Examination of these individuals 38 years later showed no physical changes believed to be related to their uranium exposure and no deposition of uranium could be detected

Lung cancer and inhaled uranium ore dust in rats

International Nuclear Information System (INIS)

Mitchel, R.E.J.; Jackson, J.S.

1997-01-01

Using a nose only inhalation system, 187 nine week old male Sprague-Dawley rats were exposed to two different concentrations of natural uranium ore dust aerosol (44% U) without significant radon content. Inhalation exposures averaged about 4.2 h/day, 5 days/week for 65 weeks at which point lung uranium burdens in the two groups averaged 0.9 and 1.9 mg/g dry weight. Animals (63) exposed to the air stream without dust served as controls. After inhalation exposure ceased, the rats were allowed to live for their natural lifetime, a maximum of about 900 days after the start of dust inhalation. Lung uranium burdens were measured at the time of death of each animal. Lung burdens were found to decline exponentially after dust inhalation ceased, and the rate of decline was independent of the initial lung burden. All lungs were examined at necropsy and histologically for lung tumors. Lung tumors of lung origin were observed in both exposed groups and in the control group. The frequency of primary malignant lung tumors was 0.016, 0.175 and 0.328 and primary non-malignant lung tumors 0.016, 0.135 and 0.131 in the control low and high aerosol exposed groups respectively. Absorbed dose to the lung was calculated for each animal in the study. The average maximum doses for all the animals exposed to the low or high concentration of dust aerosol were 0.87 Gy and 1.64 Gy respectively. The average risk of malignant lung tumors from inhaled natural uranium ore dust was therefore about 0.20 tumors/animal/Gy. For animals with lung tumors, the average doses were 0.98 and 1.90 in the exposed groups. In both exposed groups, the frequency of primary malignant or non-malignant lung tumors was significantly greater than in the control group (p < 0.02) and the frequency of primary malignant lung tumors in the two exposed group were significantly different from each other (p = 0.05). The frequency of primary lung tumors (malignant and non-malignant) was calculated as a function of dose

The use of geochemical speciation modelling to predict the impact of uranium to freshwater biota

International Nuclear Information System (INIS)

Markich, S.J.; Brown, P.L.; Jeffree, R.A.

1996-01-01

Uranium is the prime potential contaminant in mine waste waters that may be released from the Ranger Uranium Mine (RUM) into the receiving waters of the Magela Creek, Alligator Rivers Region, Northern Australia. The potential ecological impact of the migration of uranium, that would result from an elevation in its concentration above background, in the Magela Creek downstream of the RUM, has been experimentally investigated by integrating biomonitoring with geochemical speciation modelling. The freshwater bivalve Velesunio angasi, abundant throughout the Magela Creek catchment, was exposed to a variety of uranium concentrations in a synthetic Magela Creek water, at four pH levels (5.0, 5.3, 5.5 and 6.0), in the presence (3.05 and 7.50 mg l -1 ) and absence of a model fulvic acid (FA), and its behavioural response was measured. Speciation modelling, using the HARPHRQ code, provided evidence that UO 2+ 2 and UO 2 OH + are the uranium species most responsible (ca. 96%) for eliciting an adverse behavioural response when UO 2+ 2 is assigned twice the toxic effect of UO 2 OH + . This finding rejects the notion that biota respond specifically to the sum total of inorganic uranyl species. (orig.)

Uranium in Canada: 1982 assessment of supply and requirements

International Nuclear Information System (INIS)

1983-09-01

Estimates of Canada's uranium resources for 1982 remained essentially unchanged from those of 1980. However, the economic conditions facing the industry have changed greatly during the past few years as production costs continued to rise without corresponding increases in uranium prices. As a result, a smaller portion of Canada's uranium resources is of current economic interest. Total resources amount to 573 000 tonnes of uranium. Just over 10% of this uranium will be required domestically during the next 30 years to fuel the more than 15 000 megawatts of nuclear power capacity now operating or committed for operation in Canada by 1993. In 1982 seven uranium producers in Canada, directly employing 4800 people, produced concentrates containing 8075 tonnes of uranium. Based on currently committed expansion plans, Canada's projected annual production capability could grow to some 12 000 tonnes of uranium by 1986. Canadian producers shipped 7643 tonnes of uranium valued at some $838 millon in 1982. As of January 1, 1983, outstanding uranium export commitments amounted to 60 000 tonnes or roughly 10% of the total Canadian uranium resources mentioned above. Japan has been Canada's most important single customer in the past decade, receiving about 34% of Canada's total exports since 1972. Most of the remaining exports have gone to the European Economic Community (33%), other countries in Western Europe (18%), and the United States (15%). Substantial efforts in uranium exploration that have been continued, especially in northern Saskatchewan, where two-thirds of the $71 million total exploration expenditures of 1982 were incurred. This continued effort has led to the discovery of a number of important deposits over the past few years which could be developed if market conditions improve. It is estimated that total Canadian production capability could reach 15 000 tonnes of uranium annually by the mid-1990s

Uranium in Canada

International Nuclear Information System (INIS)

1989-01-01

In 1988 Canada's five uranium producers reported output of concentrate containing a record 12,470 metric tons of uranium (tU), or about one third of total Western world production. Shipments exceeded 13,200 tU, valued at $Cdn 1.1 billion. Most of Canada's uranium output is available for export for peaceful purposes, as domestic requirements represent about 15 percent of production. The six uranium marketers signed new sales contracts for over 11,000 tU, mostly destined for the United States. Annual exports peaked in 1987 at 12,790 tU, falling back to 10,430 tU in 1988. Forward domestic and export contract commitments were more than 70,000 tU and 60,000 tU, respectively, as of early 1989. The uranium industry in Canada was restructured and consolidated by merger and acquisition, including the formation of Cameco. Three uranium projects were also advanced. The Athabasca Basin is the primary target for the discovery of high-grade low-cost uranium deposits. Discovery of new reserves in 1987 and 1988 did not fully replace the record output over the two-year period. The estimate of overall resources as of January 1989 was down by 4 percent from January 1987 to a total (measured, indicated and inferred) of 544,000 tU. Exploration expenditures reached $Cdn 37 million in 1987 and $59 million in 1988, due largely to the test mining programs at the Cigar Lake and Midwest projects in Saskatchewan. Spot market prices fell to all-time lows from 1987 to mid-1989, and there is little sign of relief. Canadian uranium production capability could fall below 12,000 tU before the late 1990s; however, should market conditions warrant output could be increased beyond 15,000 tU. Canada's known uranium resources are more than sufficient to meet the 30-year fuel requirements of those reactors in Canada that are now or are expected to be in service by the late 1990s. There is significant potential for discovering additional uranium resources. Canada's uranium production is equivalent, in

Radiation hazards in uranium mining. Epidemiological and dosimetric approaches

International Nuclear Information System (INIS)

Myers, D.K.; Johnson, J.R.

1989-01-01

Potential health hazards resulting from exposure to various sources of radiation associated with uranium mining have been reviewed: 1) epidemiological observations on groups of miners exposed in the past to high concentrations of radon progeny have been interpreted to suggest a lifetime risk of about 3 x 10 -4 lung cancers per WLM; 2) the total risk of serious health effects resulting from exposure of workers to whole body gamma-radiation might be taken to be about 2 x 10 -2 per Sv; and 3) the potential health effects of inhalation of thoron progeny or of radioactive ore dusts can only be estimated from dosimetric calculations. A review of the uncertainties involved in these calculations suggests that ICRP estimates of the potential toxicity of inhaled thoron progeny are as good as those for inhaled radon progeny. However, the potential health hazards from inhaled uranium and thorium ore dusts have probably been overestimated by a factor of 2 to 10-fold

Derivation of guidelines for uranium residual radioactive material in soil at the B ampersand T Metals Company site, Columbus, Ohio

International Nuclear Information System (INIS)

Kamboj, S.; Nimmagadda, Mm.; Yu, C.

1996-01-01

Guidelines for uranium residual radioactive material in soil were derived for the B ampersand T Metals Company site in Columbus, Ohio. This site has been identified for remedial action under the US Department of Energy's (DOE's) Formerly Utilized Sites Remedial Action Program (FUSRAP). Single-nuclide and total-uranium guidelines were derived on the basis of the requirement that following remedial action, the 50-year committed effective dose equivalent to a hypothetical individual living or working in the immediate vicinity of the site should not exceed a dose constraint of 30 mrem/yr for the current use and likely future use scenarios or a dose limit of 100 n-mrem/yr for less likely future use scenarios. The DOE residual radioactive material guideline computer code, RESRAD, was used in this evaluation. RESRAD implements the methodology described in the DOE manual for establishing residual radioactive material guidelines. Three scenarios were considered; each assumed that for a period of 1,000 years following remedial action, the site would be used without radiological restrictions. The three scenarios varied with regard to the type of site use, time spent at the site by the exposed individual, and sources of food and water consumed. The evaluations indicate that the dose constraint of 30 mrem/yr would not be exceeded for uranium (including uranium-234, uranium-235, and uranium-238) within 1,000 years, provided that the soil concentration of total uranium (uranium-234, uranium-235, and uranium-238) at the B ampersand T Metals site did not exceed 1, I 00 pCi/g for Scenario A (industrial worker, current use) or 300 pCi/g for Scenario B (resident with municipal water supply, a likely future use). The dose limit of 100 mrem/yr would not be exceeded at the site if the total uranium concentration of the soil did not exceed 880 pCi/g for Scenario C (resident with an on-site water well, a plausible but unlikely future use)

Uranium-induced sensory alterations in the zebrafish Danio rerio

Energy Technology Data Exchange (ETDEWEB)

Faucher, K., E-mail: kfaucher@hotmail.fr [Laboratoire d' ecotoxicologie des radionucleides (LECO), Institut de Radioprotection et Surete Nucleaire, Centre de Cadarache, Batiment 186, BP3, 13115 Saint Paul lez Durance (France); Floriani, M.; Gilbin, R.; Adam-Guillermin, C. [Laboratoire d' ecotoxicologie des radionucleides (LECO), Institut de Radioprotection et Surete Nucleaire, Centre de Cadarache, Batiment 186, BP3, 13115 Saint Paul lez Durance (France)

2012-11-15

The effect of chronic exposure to uranium ions (UO{sub 2}{sup 2+}) on sensory tissues including the olfactory and lateral line systems was investigated in zebrafish (Danio rerio) using scanning electron microscopy. The aim of this study was to determine whether exposure to uranium damaged sensory tissues in fish. The fish were exposed to uranium at the concentration of 250 {mu}g l{sup -1} for 10 days followed by a depuration period of 23 days. Measurements of uranium uptake in different fish organs: olfactory rosettes and bulbs, brain, skin, and muscles, were also determined by ICP-AES and ICP-MS during the entire experimental period. The results showed that uranium displayed a strong affinity for sensory structures in direct contact with the surrounding medium, such as the olfactory and lateral line systems distributed on the skin. A decreasing gradient of uranium concentration was found: olfactory rosettes > olfactory bulbs > skin > muscles > brain. At the end of the experiment, uranium was present in non-negligible quantities in sensory tissues. In parallel, fish exposed to uranium showed severe sensory tissue alterations at the level of the olfactory and lateral line systems. In both sensory systems, the gross morphology was altered and the sensory hair cells were significantly damaged very early after the initiation of exposure (from the 3rd day). At the end of the experiment, after 23 days of depuration, the lateral line system still displayed slight tissue alterations, but approximately 80% of the neuromasts in this system had regenerated. In contrast, the olfactory system took more time to recover, as more than half of the olfactory rosettes observed remained destroyed at the end of the experiment. This study showed, for the first time, that uranium is able to damage fish sensory tissues to such an extent that tissue regeneration is delayed.

The Nopal 1 Uranium Deposit: an Overview

Science.gov (United States)

Calas, G.; Allard, T.; Galoisy, L.

2007-05-01

The Nopal 1 natural analogue is located in the Pena Blanca uranium district, about 50 kms north of Chihuahua City, Mexico. The deposit is hosted in tertiary ignimbritic ash-flow tuffs, dated at 44 Ma (Nopal and Colorados formations), and overlying the Pozos conglomerate formation and a sequence of Cretaceous carbonate rocks. The deposit is exposed at the ground surface and consists of a near vertical zone extending over about 100 m with a diameter of 40 m. An interesting characteristic is that the primary mineralization has been exposed above the water table, as a result of the uplift of the Sierra Pena Blanca, and subsequently oxidized with a remobilization of hexavalent uranium. The primary mineralization has been explained by various genetic models. It is associated to an extensive hydrothermal alteration of the volcanic tuffs, locally associated to pyrite and preserved by an intense silicification. Several kaolinite parageneses occur in fissure fillings and feldspar pseudomorphs, within the mineralized breccia pipe and the barren surrounding rhyolitic tuffs. Smectites are mainly developed in the underlying weakly welded tuffs. Several radiation-induced defect centers have been found in these kaolinites providing a unique picture of the dynamics of uranium mobilization (see Allard et al., this session). Another evidence of this mobilization is given by the spectroscopy of uranium-bearing opals, which show characteristic fluorescence spectra of uranyl groups sorbed at the surface of silica. By comparison with the other uranium deposits of the Sierra Pena Blanca and the nearby Sierra de Gomez, the Nopal 1 deposit is original, as it is one of the few deposits hving retained a reduced uranium mineralization.

Radioactivity of drinking waters from regions exposed to depleted uranium ammunition bombing in 2003 end 2004

International Nuclear Information System (INIS)

Tanaskovic, I.; Pantelic, G.; Vuletic, V.; Eremic Savkovic, M.; Javorina, L.J.

2006-01-01

Due to the military application of the depleted uranium in our country, the problem of its radioactivity and hemo toxicity is actualized. The locations verified to be contaminated by depleted uranium ammunition were at the South part of Serbia (Pljackovica, Bratoselce, Borovac and Reljan). The soluble forms of uranium could translocated and dispersed from soils and sediments into surface waters and groundwater. The environmental presence of depleted uranium is considered as potential threat to human health. The study presents the results of radiological safety analysis of drinking water in 2003 and 2004. All samples were analyzed by gamma spectrometry and measurements of alpha and beta activity. (authors)

The health dangers of uranium mining and jurisdictional questions

International Nuclear Information System (INIS)

Young, E.R.; Woollard, R.F.

1980-08-01

Uranium mining and milling presents a danger to the health of workers from gamma radiation, radon and thoron daughters, uranium oxides, and dust. The public is threatened by radon products, short and long term tailings failures, radium, uranium, and other chemicals. Present dose limits to workers and the public exposed to radiation from all stages of the nuclear fuel cycle have been set by organizations with vested interests in the nuclear industry and are too high. Uranium workers have in the past been poorly monitored and protected against radiation and other occupational hazards. Uranium tailings disposal methods at present are not adequate; tailings will remain hazardous for tens of thousands of years and will probably require deep geologic disposal. The non-substitutable end uses of uranium are nuclear power and nuclear weapons production, both of which have entirely unacceptable health effects

The economics of uranium demand

International Nuclear Information System (INIS)

Owen, A.D.

1983-01-01

The major characteristics of the demand for uranium are identified, and a number of factors which determine the actual level of uranium requirements of the nuclear power industry are discussed. Since the role of inventories is central to the process of short-term price formation, by comparing projections of uranium production and apparent consumption, the relative level of total inventories is calculated and an assessment is made of its likely impact on the uranium market during the 1980s. (author)

Ultrastructural observations of target-organs of the crayfish Orconectes limosus exposed to metallic pollutants: application to uranium

International Nuclear Information System (INIS)

Grasset, G.; Simon, O.; Floriani, M.

2004-01-01

Using electron microscopy associated with energy dispersive X-ray microanalysis (EDAXTEM), ultrastructure and elemental analysis in subcellular micro-localization can bring understanding to both metabolic cycle of a metallic pollutant and its potential effects at the subcellular scale. The approach consists in comparing both structures and micro-localization in various tissues/organs ultrathin sections (70-140 nm thickness) obtained from control organisms (i.e. not exposed to a given metal) and exposed organisms. However, the observations of ultrastructural effects of metal exposure involved robust comparison to reference subcellular and cellular organization. Consequently, preliminary developments presented in this poster have been performed from the non-contaminated freshwater crayfish Orconectes limosus (adult at inter-moult state). Studies of ultrastructural images and elemental composition of subcellular mineral deposits were carried out on target organs of uranium accumulation such as the digestive gland, the gills, the intestine and the antennal gland, organs participating in the detoxification, primary accumulation and depuration mechanisms. Observations indicated cell-specific architecture (identification of main organelles, frequency, length of cells), the range of natural variation of the cell organisation between individuals and identification of cellular types. Information will allow then to focus on these identified specific organization after metallic exposure. These ultrastructural observations performed on reference organisms constitute necessarily a first set of data for the cellular metallic effects analysis. (author)

Industrial types of uranium deposits in Kazakhstan

International Nuclear Information System (INIS)

Fyodorov, G.V.

2001-01-01

The main industrial uranium deposits of Kazakhstan that can be commercially mined, are located in two ore regions and are represented by two types of the uranium deposits. The first region is named Chu-Syrdarya (75.6% of total resources of Kazakhstan) and is located in the South of Kazakhstan and this one is the largest in the world among the regions of the deposits connected with the bed oxidation zone, localized in the permeable sediments and amenable for in-situ leach mining. The second region is named Kokshetau (16% of total resources) and is located in the North of Kazakhstan at the north edge of Kazak Shield and is characterized by the vein-stockwork type of deposit. Other industrial deposits (8.4% of total resources) are grouped in two regions that have been determined and are retained as reserves for economical and ecological reasons. These are: Pricaspian region with the organic phosphate type of uranium deposits; and Ili-Balkhash region with mainly the coal-uranium type. There are 44 industrial uranium deposits with resources ranging from 1000 t to 100000 t U and more in each of them, in all, in Kazakhstan. Seven of them are completely mined now. Total uranium resources in Kazakhstan are determined at 1670000 t U. (author)

Penetrate-leach dissolution of zirconium-clad uranium and uranium dioxide fuels

International Nuclear Information System (INIS)

Harmon, H.D.

1975-01-01

A new decladding-dissolution process was developed for zirconium-clad uranium metal and UO 2 fuels. The proposed penetrate-leach process consists of penetrating the zirconium cladding with Alniflex solution (2M HF--1M HNO 3 --1M Al(NO 3 ) 3 --0.1M K 2 Cr 2 O 7 ) and of leaching the exposed core with 10M HNO 3 . Undissolved cladding pieces are discarded as solid waste. Periodic HF and HNO 3 additions, efficient agitation, and in-line zirconium analyses are required for successful control of ZrF 4 and/or AlF 3 precipitation during the cladding-penetration step. Preliminary solvent extraction studies indicated complete recovery of uranium with 30 vol. percent tributyl phosphate (TBP) from both Alniflex solution and blended Alniflex-HNO 3 leach solutions. With 7.5 vol. percent TBP, high extractant/feed flow ratios and low scrub flows are required for satisfactory uranium recovery from Alniflex solution. Modified waste-handling procedures may be required for Alniflex waste, because it cannot be evaporated before neutralization and large quantities of solids are generated on neutralization. The effect of unstable UZr 3 (epsilon phase of uranium-zirconium system) on the safety of penetrate-leach dissolution was investigated

Concentration of uranium in the urine of the staff of a nuclear power plant. [Personnel engaged in chemistry and metallurgy of uranium]. Concentrazione d'uranio nelle urine del personale di un centro nucleare

Energy Technology Data Exchange (ETDEWEB)

Camera, V.; Giubileo, M.

1962-07-01

The concentration of natural uranium in the urine of 78 workers from the groups of industrial chemistry and metallurgy of uranium, was followed for 3 years. A total of 1471 analyses were done with the fluorometric method. The urine checks were done every week, or every 15 days or more according to the amount of exposure, which was evaluated by investigations done at the place of work and on the basis of information collected from the workers during the periodical medical examinations. The validity of this criterion was proved by the data obtained: the majority (74%) of the analyses of personnel least exposed revealed levels equal to or inferior to 1 gamma/liter, whereas (66%) the group with an intermediate risk showed 1 to 5 gamma/liter, and in the group most exposed levels of 5-10 gamma/liter were found in 37% of the cases; from 10-20 gamma/liter in 19%; and from 20-50 gamma/liter in 7% of the cases. Only 1% of the samples had a level superior to 50 gamma/liter. The attempt to establish a correlation between the level of uranium found in the air and in the urine gave no tenable indication concerning the real work risk, due to the variability of atmospheric contamination with time and the incessant movement of almost all the workers from one laboratory to another during the day.

Mortality in the French TRACY cohort of uranium cycle workers

International Nuclear Information System (INIS)

Nicolle-Mir, Laurence

2016-01-01

This first analysis of mortality in a new cohort of French uranium cycle workers observed a healthy worker effect, as shown by a large all-cause mortality deficit. The current reconstruction of exposure data (radiological, chemical, and physical) will make it possible to study the risks specific to internal uranium contamination in individuals exposed to multiple agents. (author)

Ecological considerations of natural and depleted uranium

International Nuclear Information System (INIS)

Hanson, W.C.

1980-01-01

Depleted 238 U is a major by-product of the nuclear fuel cycle for which increasing use is being made in counterweights, radiation shielding, and ordnance applications. This paper (1) summarizes the pertinent literature on natural and depleted uranium in the environment, (2) integrates results of a series of ecological studies conducted at Los Alamos Scientific Laboratory (LASL) in New Mexico where 70,000 kg of depleted and natural uranium has been expended to the environment over the past 34 years, and (3) synthesizes the information into an assessment of the ecological consequences of natural and depleted uranium released to the environment by various means. Results of studies of soil, plant, and animal communities exposed to this radiation and chemical environment over a third of a century provide a means of evaluating the behavior and effects of uranium in many contexts

Concentration of uranium in the urine of the staff of a nuclear power plant. [Personnel engaged in chemistry and metallurgy of uranium]. Concentrazione d'uranio nelle urine del personale di un centro nucleare

Energy Technology Data Exchange (ETDEWEB)

Camera, V.; Giubileo, M.

1962-07-01

The concentration of natural uranium in the urine of 78 workers from the groups of industrial chemistry and metallurgy of uranium, was followed for 3 years. A total of 1471 analyses were done with the fluorometric method. The urine checks were done every week, or every 15 days or more according to the amount of exposure, which was evaluated by investigations done at the place of work and on the basis of information collected from the workers during the periodical medical examinations. The validity of this criterion was proved by the data obtained: the majority (74%) of the analyses of personnel least exposed revealed levels equal to or inferior to 1 gamma/liter, whereas (66%) the group with an intermediate risk showed 1 to 5 gamma/liter, and in the group most exposed levels of 5-10 gamma/liter were found in 37% of the cases; from 10-20 gamma/liter in 19%; and from 20-50 gamma/liter in 7% of the cases. Only 1% of the samples had a level superior to 50 gamma/liter. The attempt to establish a correlation between the level of uranium found in the air and in the urine gave no tenable indication concerning the real work risk, due to the variability of atmospheric contamination with time and the incessant movement of almost all the workers from one laboratory to another during the day.

Study of uranium transfer across the blood-brain barrier

Energy Technology Data Exchange (ETDEWEB)

Lemercier, V.; Millot, X.; Ansoborlo, E.; Menetrier, F.; Fluery-Herard, A.; Rousselle, Ch.; Scherrmann, J.M

2003-07-01

Uranium is a heavy metal which, following accidental exposure, may potentially be deposited in human tissues and target organs, the kidneys and bones. A few published studies have described the distribution of this element after chronic exposure and one of them has demonstrated an accumulation in the brain. In the present study, using inductively coupled plasma mass spectrometry (ICP-MS) for the quantification of uranium, uranium transfer across the blood-brain barrier (BBB) has been assessed using the in situ brain perfusion technique in the rat. For this purpose, a physiological buffered bicarbonate saline at pH 7.4 containing natural uranium at a given concentration was perfused. After checking the integrity of the BBB during the perfusion, the background measurement of uranium in control rats without uranium in the perfusate was determined. The quantity of uranium in the exposed rat hemisphere, which appeared to be significantly higher than that in the control rats, was measured. Finally, the possible transfer of the perfused uranium not only in the vascular space but also in the brain parenchyma is discussed. (author)

An evaluation of health risk to the public as a consequence of in situ uranium mining in Wyoming, USA.

Science.gov (United States)

Ruedig, Elizabeth; Johnson, Thomas E

2015-12-01

In the United States there is considerable public concern regarding the health effects of in situ recovery uranium mining. These concerns focus principally on exposure to contaminants mobilized in groundwater by the mining process. However, the risk arising as a result of mining must be viewed in light of the presence of naturally occurring uranium ore and other constituents which comprise a latent hazard. The United States Environmental Protection Agency recently proposed new guidelines for successful restoration of an in situ uranium mine by limiting concentrations of thirteen groundwater constituents: arsenic, barium, cadmium, chromium, lead, mercury, selenium, silver, nitrate (as nitrogen), molybdenum, radium, total uranium, and gross α activity. We investigated the changes occurring to these constituents at an ISR uranium mine in Wyoming, USA by comparing groundwater quality at baseline measurement to that at stability (post-restoration) testing. Of the groundwater constituents considered, only uranium and radium-226 showed significant (p < 0.05) deviation from site-wide baseline conditions in matched-wells. Uranium concentrations increased by a factor of 5.6 (95% CI 3.6-8.9 times greater) while radium-226 decreased by a factor of about one half (95% CI 0.42-0.75 times less). Change in risk was calculated using the RESRAD (onsite) code for an individual exposed as a resident-farmer; total radiation dose to a resident farmer decreased from pre-to post-mining by about 5.2 mSv y(-1). Higher concentrations of uranium correspond to increased biomarkers of nephrotoxicity, however the clinical significance of this increase is unclear. Published by Elsevier Ltd.

Optimization of Davies and Gray/NBL method used for determination of total uranium concentration in the safeguards destructive analysis

International Nuclear Information System (INIS)

Silva, Jose Wanderley S. da; Viana, Aline Gonzalez; Barros, Pedro Dionisio de; Cristiano, Barbara Fernandes G.

2013-01-01

One important activity conducted by the Brazilian State System of Accounting for and Control of Nuclear Materials - SSAC is to verify inventories of the nuclear facilities by nondestructive analysis and destructive analysis. For destructive analysis, the Safeguards Laboratory of Brazilian Nuclear Energy Commission - LASAL/CNEN has been applying the 'Davies and Gray/NBL' method in samples taken during inspections at nuclear facilities since 1984 in Brazil and Argentina. This method consists of the determination of total uranium concentration by potentiometric titration of uranium (IV) with a standard solution of potassium dichromate as oxidizing agent. This solution is prepared using a K 2 Cr 2 O 7 SRM 136e standard reference material (99.984 ±0.010) wt% certified by National Institute of Standard and Technology - NIST. The procedure also includes the calibration with primary uranium standards reference material (NBL CRM 112A). In order to reduce the consumption of K 2 Cr 2 O 7 and the other reagent involved in the procedure, without any loss in the performance of the method, a K 2 Cr 2 O 7 solution with half the regular concentration was prepared and used to test the uranium concentration in several aliquots with a content between 30 mg to 40 mg of uranium per gram of solution. After optimizing the parameters and procedure, it was possible to get the same performance as well. As a consequence, decreasing of the cost, the amount of waste and also a reduction in the titration time of each aliquot was achieved. Thus, this work describes all details in this research as well as the results and its evaluation. (author)

The U.S. Department of Veterans' Affairs depleted uranium exposed cohort at 25 Years: Longitudinal surveillance results

Energy Technology Data Exchange (ETDEWEB)

McDiarmid, Melissa A.; Gaitens, Joanna M.; Hines, Stella [Department of Veterans Affairs Medical Center Baltimore, Maryland, 10 N. Greene St., Baltimore, MD 21201 (United States); Department of Medicine, University of Maryland School of Medicine, 655 W Baltimore S, Baltimore, MD 21201 (United States); Condon, Marian, E-mail: mcondon@medicine.umaryland.edu [Department of Veterans Affairs Medical Center Baltimore, Maryland, 10 N. Greene St., Baltimore, MD 21201 (United States); Roth, Tracy; Oliver, Marc; Gucer, Patricia [Department of Veterans Affairs Medical Center Baltimore, Maryland, 10 N. Greene St., Baltimore, MD 21201 (United States); Department of Medicine, University of Maryland School of Medicine, 655 W Baltimore S, Baltimore, MD 21201 (United States); Brown, Lawrence [Department of Veterans Affairs Medical Center Baltimore, Maryland, 10 N. Greene St., Baltimore, MD 21201 (United States); Department of Pathology, University of Maryland School of Medicine, 655 W Baltimore S, Baltimore, MD 21201 (United States); Centeno, Jose A. [US Food and Drug Administration, Center for Devices and Radiological Health Office of Science and Engineering Laboratories, Silver Spring, MD 20993 (United States); Dux, Moira [Department of Veterans Affairs Medical Center Baltimore, Maryland, 10 N. Greene St., Baltimore, MD 21201 (United States); Squibb, Katherine S. [Department of Veterans Affairs Medical Center Baltimore, Maryland, 10 N. Greene St., Baltimore, MD 21201 (United States); Department of Medicine, University of Maryland School of Medicine, 655 W Baltimore S, Baltimore, MD 21201 (United States)

2017-01-15

Background: A small group of Gulf War I veterans wounded in depleted uranium (DU) friendly-fire incidents have been monitored for health changes in a clinical surveillance program at the Veterans Affairs Medical Center, Baltimore since 1994. Methods: During the spring of 2015, an in-patient clinical surveillance protocol was performed on 36 members of the cohort, including exposure monitoring for total and isotopic uranium concentrations in urine and a comprehensive assessment of health outcomes. Results: On-going mobilization of U from embedded fragments is evidenced by elevated urine U concentrations. The DU isotopic signature is observed principally in participants possessing embedded fragments. Those with only an inhalation exposure have lower urine U concentration and a natural isotopic signature. Conclusions: At 25 years since first exposure to DU, an aging cohort of military veterans continues to show no U-related health effects in known target organs of U toxicity. As U body burden continues to accrue from in-situ mobilization from metal fragment depots, and increases with exposure duration, critical tissue-specific U concentration thresholds may be reached, thus recommending on-going surveillance of this veteran cohort. - Highlights: • Gulf War I veterans wounded with depleted uranium are monitored for health changes. • In 2015 in-patient clinical surveillance was performed on 36 members of the cohort. • Mobilization of U from embedded fragments is evidenced by elevated U in urine. • This cohort of continues to show no U-related health effects.

The U.S. Department of Veterans' Affairs depleted uranium exposed cohort at 25 Years: Longitudinal surveillance results

International Nuclear Information System (INIS)

McDiarmid, Melissa A.; Gaitens, Joanna M.; Hines, Stella; Condon, Marian; Roth, Tracy; Oliver, Marc; Gucer, Patricia; Brown, Lawrence; Centeno, Jose A.; Dux, Moira; Squibb, Katherine S.

2017-01-01

Background: A small group of Gulf War I veterans wounded in depleted uranium (DU) friendly-fire incidents have been monitored for health changes in a clinical surveillance program at the Veterans Affairs Medical Center, Baltimore since 1994. Methods: During the spring of 2015, an in-patient clinical surveillance protocol was performed on 36 members of the cohort, including exposure monitoring for total and isotopic uranium concentrations in urine and a comprehensive assessment of health outcomes. Results: On-going mobilization of U from embedded fragments is evidenced by elevated urine U concentrations. The DU isotopic signature is observed principally in participants possessing embedded fragments. Those with only an inhalation exposure have lower urine U concentration and a natural isotopic signature. Conclusions: At 25 years since first exposure to DU, an aging cohort of military veterans continues to show no U-related health effects in known target organs of U toxicity. As U body burden continues to accrue from in-situ mobilization from metal fragment depots, and increases with exposure duration, critical tissue-specific U concentration thresholds may be reached, thus recommending on-going surveillance of this veteran cohort. - Highlights: • Gulf War I veterans wounded with depleted uranium are monitored for health changes. • In 2015 in-patient clinical surveillance was performed on 36 members of the cohort. • Mobilization of U from embedded fragments is evidenced by elevated U in urine. • This cohort of continues to show no U-related health effects.

Uranium's effects on bone integrity

International Nuclear Information System (INIS)

Souidi, Maamar; Wade-Gueye, Ndeye Marieme; Manens, Line; Blanchardon, Eric; Aigueperse, Jocelyne

2018-01-01

Uranium is a radioactive heavy metal naturally present in the environment. Its recent use in various civilian and military applications sometimes result in its release into the environment. After chronic ingestion, uranium accumulates in various organs, preferentially in bones. Several studies have shown that exposure to high concentrations of uranium affects bone growth. Little is known, however, about the effects of chronic exposure to low doses of uranium on bone, especially when ingested via drinking water, the main route by which the public is exposed to this radionuclide. This study examined the effects of chronic exposure to natural uranium through drinking water on bone integrity and bone turnover. Rats were contaminated with different concentrations of natural uranium (15, 10, and 40 mg / l) for 9 months. A high-resolution three-dimensional microtomography scanner was used for the first time to study uranium's impact on bone metabolism and thus on bone tissue integrity. After nine months of uranium exposure, micro-architecture analysis revealed that the cortical bone diameter of the femoral diaphysis of rats contaminated at a concentration of 40 mg/L of uranium had decreased significantly. In conclusion, our findings that chronic ingestion of uranium at low concentrations affects growth of cortical bone width suggests that it may affect bone strength. These results thus suggest the need to pay special attention to children during chronic low-dose exposure to this radionuclide. (authors)

Excretion of depleted uranium by Gulf war veterans

International Nuclear Information System (INIS)

Toohey, R.E.

2003-01-01

During the Persian Gulf War, in 1991, approximately 100 US military personnel had potential intakes of depleted uranium (DU), including shrapnel wounds. In 1993, the US government initiated a follow-up study of 33 Gulf War veterans who had been exposed to DU, many of whom contained embedded fragments of DU shrapnel in their bodies. The veterans underwent medical evaluation, whole-body counting, and urinalysis for uranium by kinetic phosphorescence analysis (KPA). Data are available from seven individuals who exceeded the detection limit for whole-body counting and also had elevated urinary uranium. Urinary excretion rates, in μg U g -1 creatinine, were determined in 1997 and 1999. The body contents, in mg DU, were determined in 1997; it is assumed there were no significant decreases in total body content in the interim. For the 1997 data, the mean fractional excretion was (2.4 ± 2.8) x 10 -5 g -1 creatinine, and for the 1999 data, the mean was (1.1 ± 0.6) x 10 -5 g -1 creatinine. However, these means are not significantly different, nor is there any correlation of excretion rate with body content. Thus, human data available to date do not provide any basis for determining the effects of particle surface area, composition and solubility, and biological processes such as encapsulation, on the excretion rate. (author)

Review of uranium excretion and clinical urinalysis data in accidental exposure cases

International Nuclear Information System (INIS)

Boback, M.W.

1975-01-01

This report reviews urinalysis results obtained following four incidents in which thirteen workers were exposed to high concentrations of airborne uranium. The compounds involved were U 3 O 8 , UF 6 , and uranium ore concentrates. Urine samples collected following these exposures were always analyzed for uranium, and in some cases, for specific gravity, pH, protein, sugar, white blood cells, red blood cells, and casts. Although urinary uranium concentrations exceeded 1 mg U/1, no evidence was found to indicate kidney damage as a result of these exposures

X-ray photoelectron spectroscopy of the uranium/oxygen system: Part 13

International Nuclear Information System (INIS)

Allen, G.C.; Stevens, J.C.H.

1987-02-01

The reaction between commercial H 2 and uranium metal leads to the formation of UO 2 due to traces of water vapour or oxygen. When extremely pure H 2 is used uranium hydride may be formed but, even with 99.9999% H 2 , uranium dioxide forms preferentially. The present work identifies the presence of UH 3 in the X-ray photoelectron spectrum of a uranium sample which has been exposed to ∼ 5 mbar H 2 at ∼ 200 0 C for 1 hour. This spectrum indicates that the hydride possesses a high degree of covalency, since the oxidation state of uranium in UH 3 appears to be ∼ 1.4. (U.K.)

Application of alkaline leaching to the extraction of uranium from shale of the Vosges; Application de la lixiviation alcaline a l'extraction de l'uranium du schiste des Vosges

Energy Technology Data Exchange (ETDEWEB)

Mouret, P; Pottier, P; Le Bris, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Soudan, P [Centre d' Etude de Lalumine, Compagnie Pechiney (France)

1958-07-01

Description of chemical treatment of Vosges shales to obtain uranium by alkaline leaching. Mineralogy aspects of ore, physical and chemical conditions of leaching, solid/liquid separation, uranium recovery by either ion exchange process or electrolytic precipitation. (author)Fren. [French] Description du traitement chimique des schistes des Vosges pour extraire l'uranium en milieu alcalin. L'aspect mineralogique, les conditions physiques et chimiques de la lixiviation, la separation solide/liquide et la recuperation de l'uranium soit par echangeurs d'ions, soit par precipitation electrolytique y sont exposes. (auteur)

Inhalation hazards to uranium miners

International Nuclear Information System (INIS)

Cross, F.T.

1987-01-01

Using both large and small experimental animals, this project is investigating levels of uranium-mine air contaminants that produce respiratory system disease in miners. Lung cancer incidence and deaths from degenerative lung disease are significantly elevated among uranium miners, but the cause-effect relationships for these diseases are based on inadequate epidemiological data. This project identifies agents or combinations of agents (both chemical and radiological), and their exposure levels, that produce respiratory tract lesions, including respiratory epithelial carcinoma, pneumoconiosis, and emphysema. Histopathological data for 100-working-level (WL) exposure rates show a significant increase in lung tumor risk over 1000-WL exposure rates for comparable cumulative radon-daughter exposures. Exposure of rats to radon daughters and other contaminants continues; the exposure of beagle dogs to uranium ore dust alone was terminated. Renal function and hematology data on ore-dust-exposed dogs are reported. 1 figure, 5 tables

Development of on-line uranium enrichment monitor of gaseous UF6 for uranium enrichment plant

International Nuclear Information System (INIS)

Lu Xuesheng; Liu Guorong; Jin Huimin; Zhao Yonggang; Li Jinghuai; Hao Xueyuan; Ying Bin; Yu Zhaofei

2013-01-01

An on-line enrichment monitor was developed to measure the enrichment of UF 6 , flowing through the processing pipes in uranium enrichment plant. A Nal (Tl) detector was used to measure the count rates of the 185.7 keV γ-ray emitted from 235 U, and the total quantity of uranium was determined from thermodynamic characteristics of gaseous uranium hexafluoride. The results show that the maximum relative standard deviation is less than 1% when the measurement time is 120 s or more and the pressure is more than 2 kPa in the measurement chamber. Uranium enrichment of gaseous uranium hexafluoride in the output end of cascade can be monitored continuously by using the device. It should be effective for nuclear materials accountability verifications and materials balance verification at uranium enrichment plant. (authors)

Early stress responses in Atlantic salmon (Salmo salar) exposed to environmentally relevant concentrations of uranium

International Nuclear Information System (INIS)

Song You; Salbu, Brit; Heier, Lene Sørlie; Teien, Hans-Christian; Lind, Ole-Christian; Oughton, Deborah; Petersen, Karina; Rosseland, Bjørn Olav; Skipperud, Lindis; Tollefsen, Knut Erik

2012-01-01

Uranium (U) is a naturally occurring heavy metal widely used in many military and civil applications. Uranium contamination and the associated potential adverse effects of U on the aquatic environment have been debated during recent years. In order to understand the effect and mode of action (MoA) of U in vivo, juvenile Atlantic salmon (Salmo salar) were exposed to 0.25 mg/L, 0.5 mg/L and 1.0 mg/L waterborne depleted uranyl acetate, respectively, in a static system for 48 h. The U concentrations in the gill and liver were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and the resulting biological effects were determined by a combination of analysis of gene expression and micronuclei formation. The hepatic transcriptional level of 12 biomarker genes from four stress–response categories, including oxidative stress (γ-glutamyl cysteine synthetase (GCS), glutathione reductase (GR), glutathione peroxidase (GPx)), DNA damage and repair (P53, cyclin-dependent kinase inhibitor 1 (P21), growth arrest and DNA damage-inducible gene gamma (Gadd45G), proliferating cell nuclear antigen (PCNA), Rad51), apoptosis (Bcl2-associated X protein (BAX), Bcl-x, Caspase 6A,) and protein degradation (Ubiquitin) were evaluated by quantitative real-time polymerase chain reaction (q-rtPCR). The results clearly showed accumulation of U in the gill and liver with increasing concentrations of U in the exposure water. The effects of U on differential hepatic gene expression also occurred in a concentration-dependent manner, although deviations from ideal concentration–response relationships were observed at the highest U concentration (1.0 mg/L). All the genes tested were found to be up-regulated by U while no significant micronuclei formation was identified. The results suggest that U may cause oxidative stress in fish liver at concentrations greater than 0.25 mg/L, giving rise to clear induction of several toxicologically relevant biomarker genes, although no significant

Optimization of Davies and Gray/NBL method used for determination of total uranium concentration in the safeguards destructive analysis

Energy Technology Data Exchange (ETDEWEB)

Silva, Jose Wanderley S. da; Viana, Aline Gonzalez; Barros, Pedro Dionisio de; Cristiano, Barbara Fernandes G., E-mail: wanderley@ird.gov.br, E-mail: agonzalez@ird.gov.br, E-mail: pedrodio@ird.gov.br, E-mail: barbara@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

2013-07-01

One important activity conducted by the Brazilian State System of Accounting for and Control of Nuclear Materials - SSAC is to verify inventories of the nuclear facilities by nondestructive analysis and destructive analysis. For destructive analysis, the Safeguards Laboratory of Brazilian Nuclear Energy Commission - LASAL/CNEN has been applying the 'Davies and Gray/NBL' method in samples taken during inspections at nuclear facilities since 1984 in Brazil and Argentina. This method consists of the determination of total uranium concentration by potentiometric titration of uranium (IV) with a standard solution of potassium dichromate as oxidizing agent. This solution is prepared using a K{sub 2}Cr{sub 2}O{sub 7} SRM 136e standard reference material (99.984 ±0.010) wt% certified by National Institute of Standard and Technology - NIST. The procedure also includes the calibration with primary uranium standards reference material (NBL CRM 112A). In order to reduce the consumption of K{sub 2}Cr{sub 2}O{sub 7} and the other reagent involved in the procedure, without any loss in the performance of the method, a K{sub 2}Cr{sub 2}O{sub 7} solution with half the regular concentration was prepared and used to test the uranium concentration in several aliquots with a content between 30 mg to 40 mg of uranium per gram of solution. After optimizing the parameters and procedure, it was possible to get the same performance as well. As a consequence, decreasing of the cost, the amount of waste and also a reduction in the titration time of each aliquot was achieved. Thus, this work describes all details in this research as well as the results and its evaluation. (author)

The utility of in vitro solubility testing in assessment of uranium exposure

International Nuclear Information System (INIS)

Eidson, A.F.; Damon, E.G.; Hahn, F.F.; Griffith, W.C. Jr.

1989-01-01

Assessment of accidental exposures in the uranium industry requires estimation of retention and excretion rates using bioassay measurements. This task is difficult if the solubility of the inhaled uranium compound is unknown. In our research, Beagle dogs were exposed to aerosols of commercial uranium milling products containing either pure ammonium diuranate (ADU) or U 3 0 8 . Dogs were exposed to ADU aerosols to achieve a median retained body burden of 0.058 mg U per kg body weight, or to U 3 0 8 aerosols to achieve a median retained body burden of 0.28 mg U per kg. A biokinetic model was applied to simulate retention and excretion of the two forms of uranium in vivo. Comparison of published in vitro dissolution data and modelling results with information from accidental human exposures showed that in vitro dissolution studies are necessary to characterise the differential solubilities of uranium compounds, and indicate the potential for kidney toxicity. Because variability in pulmonary clearance and urinary excretion rates is high among individual people, in vitro dissolution results are only marginally useful for estimating urinary excretion rates. (author)

Chemical treatment of uranium ores in France

International Nuclear Information System (INIS)

Mouret, P.; Sartorius, R.

1958-01-01

The various processes of chemical treatment of uranium ores, from the oldest to the more recent, are exposed, considering the following conditions: economics, geography, techniques and safety. The interest of obtaining a final concentrate as uranyl nitrate is discussed. (author) [fr

Uranium

International Nuclear Information System (INIS)

Gabelman, J.W.; Chenoweth, W.L.; Ingerson, E.

1981-01-01

The uranium production industry is well into its third recession during the nuclear era (since 1945). Exploration is drastically curtailed, and many staffs are being reduced. Historical market price production trends are discussed. A total of 3.07 million acres of land was acquired for exploration; drastic decrease. Surface drilling footage was reduced sharply; an estimated 250 drill rigs were used by the uranium industry during 1980. Land acquisition costs increased 8%. The domestic reserve changes are detailed by cause: exploration, re-evaluation, or production. Two significant discoveries of deposits were made in Mohave County, Arizona. Uranium production during 1980 was 21,850 short tons U 3 O 8 ; an increase of 17% from 1979. Domestic and foreign exploration highlights were given. Major producing areas for the US are San Juan basin, Wyoming basins, Texas coastal plain, Paradox basin, northeastern Washington, Henry Mountains, Utah, central Colorado, and the McDermitt caldera in Nevada and Oregon. 3 figures, 8 tables

Airborne uranium, its concentration and toxicity in uranium enrichment facilities

International Nuclear Information System (INIS)

Thomas, J.; Mauro, J.; Ryniker, J.; Fellman, R.

1979-02-01

The release of uranium hexafluoride and its hydrolysis products into the work environment of a plant for enriching uranium by means of gas centrifuges is discussed. The maximum permissible mass and curie concentration of airborne uranium (U) is identified as a function of the enrichment level (i.e., U-235/total U), and chemical and physical form. A discussion of the chemical and radiological toxicity of uranium as a function of enrichment and chemical form is included. The toxicity of products of UF 6 hydrolysis in the atmosphere, namely, UO 2 F 2 and HF, the particle size of toxic particulate material produced from this hydrolysis, and the toxic effects of HF and other potential fluoride compounds are also discussed. Results of an investigation of known effects of humidity and temperature on particle size of UO 2 F 2 produced by the reaction of UF 6 with water vapor in the air are reported. The relationship of the solubility of uranium compounds to their toxic effects was studied. Identification and discussion of the standards potentially applicable to airborne uranium compounds in the working environment are presented. The effectiveness of High Efficiency Particulate (HEPA) filters subjected to the corrosive environment imposed by the presence of hydrogen fluoride is discussed

Epigenetic, histopathological and transcriptomic effects following exposure to depleted uranium in adult zebrafish and their progeny

Energy Technology Data Exchange (ETDEWEB)

Gombeau, Kewin, E-mail: kewin.gombeau@gmail.com [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Bourdineaud, Jean-Paul, E-mail: jean-paul.bourdineaud@u-bordeaux.fr [Université de Bordeaux, CNRS, UMR 5805, EPOC, 33400 Talence (France); Ravanat, Jean-Luc, E-mail: jean-luc.ravanat@cea.fr [Univ. Grenoble Alpes, INAC-SyMMES, 38000 Grenoble (France); CEA, INAC-SCIB Laboratoire des Lésions des Acides Nucléiques, 38000 Grenoble (France); Armant, Olivier, E-mail: olivier.armant@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Camilleri, Virginie, E-mail: virginie.camilleri@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Cavalie, Isabelle, E-mail: isabelle.cavalie@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Floriani, Magali, E-mail: magali.floriani@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); and others

2017-03-15

Highlights: • The parental DU-exposure induced a significant transfer of uranium into eggs. • Du-exposed progeny exhibited a significant 2-fold increased DNA methylation level. • The transcriptomic response was deeply modified in the DU-exposed organisms. • DU-exposed adult and offspring presented significant histopathological injuries. - Abstract: This study investigated the effects of adult zebrafish exposure to a nominal concentration of 20 μg L{sup −1} of depleted uranium (DU) for six days upon DNA methylation, gene expression and the appearance of histopathological damage in their progeny. In the embryos at the 2–8 cell stage, the parental exposure induced significant DU accumulation, with levels seven times higher than those measured in the control embryos, but in larvae 96 h post-fertilisation (hpf), uranium concentration had already returned to a level identical to that of the control larvae. A significant two-fold increase in the global level of DNA methylation was observed in embryos as early as the prim5 (24 hpf) stage and was still maintained at the 96 hpf stage despite the fact that DU had already been depurated at the later stage. RNA sequencing analysis indicated an impact of parental exposure upon the total RNAs transmitted from the mother to eggs, and the up-regulated genes were those associated with post-traductional protein modification and trafficking and cellular signalling pathways, whereas the down-regulated genes concerned the translational process, cell cycle regulation and several cell signalling pathways. Alterations of photoreceptor cells and the axon-axon junctions between photoreceptors were observed in the eyes of adult fish exposed for 10 days to DU. Actin and myosin filament disorganisation was observed in the skeletal muscles of 96 hpf larvae, at a stage when the maternally transmitted DU had already been excreted. These data reveal the extreme sensitivity of zebrafish embryos to DU transmitted through the oocyte by

Epigenetic, histopathological and transcriptomic effects following exposure to depleted uranium in adult zebrafish and their progeny

International Nuclear Information System (INIS)

Gombeau, Kewin; Bourdineaud, Jean-Paul; Ravanat, Jean-Luc; Armant, Olivier; Camilleri, Virginie; Cavalie, Isabelle; Floriani, Magali

2017-01-01

Highlights: • The parental DU-exposure induced a significant transfer of uranium into eggs. • Du-exposed progeny exhibited a significant 2-fold increased DNA methylation level. • The transcriptomic response was deeply modified in the DU-exposed organisms. • DU-exposed adult and offspring presented significant histopathological injuries. - Abstract: This study investigated the effects of adult zebrafish exposure to a nominal concentration of 20 μg L −1 of depleted uranium (DU) for six days upon DNA methylation, gene expression and the appearance of histopathological damage in their progeny. In the embryos at the 2–8 cell stage, the parental exposure induced significant DU accumulation, with levels seven times higher than those measured in the control embryos, but in larvae 96 h post-fertilisation (hpf), uranium concentration had already returned to a level identical to that of the control larvae. A significant two-fold increase in the global level of DNA methylation was observed in embryos as early as the prim5 (24 hpf) stage and was still maintained at the 96 hpf stage despite the fact that DU had already been depurated at the later stage. RNA sequencing analysis indicated an impact of parental exposure upon the total RNAs transmitted from the mother to eggs, and the up-regulated genes were those associated with post-traductional protein modification and trafficking and cellular signalling pathways, whereas the down-regulated genes concerned the translational process, cell cycle regulation and several cell signalling pathways. Alterations of photoreceptor cells and the axon-axon junctions between photoreceptors were observed in the eyes of adult fish exposed for 10 days to DU. Actin and myosin filament disorganisation was observed in the skeletal muscles of 96 hpf larvae, at a stage when the maternally transmitted DU had already been excreted. These data reveal the extreme sensitivity of zebrafish embryos to DU transmitted through the oocyte by exposed

Standard test methods for analysis of sintered gadolinium oxide-uranium dioxide pellets

CERN Document Server

American Society for Testing and Materials. Philadelphia

2006-01-01

1.1 These test methods cover procedures for the analysis of sintered gadolinium oxide-uranium dioxide pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Section Carbon (Total) by Direct CombustionThermal Conductivity Method C1408 Test Method for Carbon (Total) in Uranium Oxide Powders and Pellets By Direct Combustion-Infrared Detection Method Chlorine and Fluorine by Pyrohydrolysis Ion-Selective Electrode Method C1502 Test Method for Determination of Total Chlorine and Fluorine in Uranium Dioxide and Gadolinium Oxide Gadolinia Content by Energy-Dispersive X-Ray Spectrometry C1456 Test Method for Determination of Uranium or Gadolinium, or Both, in Gadolinium Oxide-Uranium Oxide Pellets or by X-Ray Fluorescence (XRF) Hydrogen by Inert Gas Fusion C1457 Test Method for Determination of Total Hydrogen Content of Uranium Oxide Powders and Pellets by Carrier Gas Extraction Isotopic Uranium Composition by Multiple-Filament Surface-Ioni...

Gulf war depleted uranium risks.

Science.gov (United States)

Marshall, Albert C

2008-01-01

US and British forces used depleted uranium (DU) in armor-piercing rounds to disable enemy tanks during the Gulf and Balkan Wars. Uranium particulate is generated by DU shell impact and particulate entrained in air may be inhaled or ingested by troops and nearby civilian populations. As uranium is slightly radioactive and chemically toxic, a number of critics have asserted that DU exposure has resulted in a variety of adverse health effects for exposed veterans and nearby civilian populations. The study described in this paper used mathematical modeling to estimate health risks from exposure to DU during the 1991 Gulf War for both US troops and nearby Iraqi civilians. The analysis found that the risks of DU-induced leukemia or birth defects are far too small to result in an observable increase in these health effects among exposed veterans or Iraqi civilians. The analysis indicated that only a few ( approximately 5) US veterans in vehicles accidentally targeted by US tanks received significant exposure levels, resulting in about a 1.4% lifetime risk of DU radiation-induced fatal cancer (compared with about a 24% risk of a fatal cancer from all other causes). These veterans may have also experienced temporary kidney damage. Iraqi children playing for 500 h in DU-destroyed vehicles are predicted to incur a cancer risk of about 0.4%. In vitro and animal tests suggest the possibility of chemically induced health effects from DU internalization, such as immune system impairment. Further study is needed to determine the applicability of these findings for Gulf War exposure to DU. Veterans and civilians who did not occupy DU-contaminated vehicles are unlikely to have internalized quantities of DU significantly in excess of normal internalization of natural uranium from the environment.

Current status and future prospects of uranium resources

International Nuclear Information System (INIS)

Kuronuma, Chosuke

1997-01-01

Uranium is contained in various things in natural world, for example, 3 ppm in granite and 3x10 -3 ppm in seawater. Uranium exists in the state of tetra, penta and hexa-valence in nature, and in oxidizing environment, it exists as uranyl radical of hexa-valence, forms soluble complexes, and easily moves with water. In reducing environment, it becomes insoluble state of tetra-valence and precipitates. This property of uranium is deeply related to the way of forming the deposit, and it is explained. The uranium resources of the recovery cost being 80 dollars per kg U or less are 2,120,000 t, and 60% of the total exists in Australia, Kazakstan and Canada. The cumulative production of uranium in the world from 1945 to 1995 was 1,810,000 t. Of the total production, 875,000 t was used for civil purpose, and 750,000 t was used for military purpose. The uranium deposits in Canada are very high quality, and produce 1/3 of the world uranium production. There are the inventories of 150,000-200,000 t U. The diversion of military high enriched uranium to civil purpose is reported. The state of uranium market, the prospect of demand and supply of uranium, and the exploration and development of uranium resources are described. (K.I.)

Developments in uranium in 1986

International Nuclear Information System (INIS)

Chenoweth, W.L.

1987-01-01

Imported uranium and low prices continued to plague the domestic uranium industry and, as a result, the Secretary of Energy declared the domestic industry to be nonviable for the second straight year. Uranium exploration expenditures in the US declined for the eighth consecutive year. In 1986, an estimated $19 million was spent on uranium exploration, including 1.9 million ft of surface drilling. This drilling was done mainly in producing areas and in areas of recent discoveries. Production of uranium concentrate increased in 1986, when 13.8 million lb of uranium oxide (U 3 O 8 ) were produced, a 22% increase over 1985. Uranium produced as the result of solution mining and as the by-product of phosphoric acid production accounted for about 37% of the total production in the US. At the end of 1986, only 6 uranium mills were operating in the US. Canada continued to dominate the world market. The development under way at the huge Olympic Dam deposit in Australia will increase that country's production. US uranium production is expected to show a small decrease in 1987. 3 figures, 2 tables

Calibration of uranium 232 solution

International Nuclear Information System (INIS)

Galan, M.P.; Acena, M.L.

1988-01-01

A method for acertainning the activity by alpha spectroscopy with semiconductor detectors, of a solution of Uranium-232 is presented. It consists of the comparison with a Uranium-233 solution activity previously measured in a gridded ionization chamber of 2 π geometry. The total measurement uncertainty is about +- 0,02. (Author)

Recovering uranium from phosphoric acid

International Nuclear Information System (INIS)

Anon.

1979-01-01

Wet-process phosphoric acid contains a significant amount of uranium. This uranium totals more than 1,500 tons/yr in current U.S. acid output--and projections put the uranium level at 8,000 tons/yr in the year 2000. Since the phosphoric acid is a major raw material for fertilizers, uranium finds its way into those products and is effectively lost as a resource, while adding to the amount of radioactive material that can contaminate the food chain. So, resource-conservation and environmental considerations both make recovery of the uranium from phosphoric acid desirable. This paper describes the newly developed process for recovering uranium from phosphoric acid by using solvent-extraction technique. After many extractants had been tested, the researchers eventually selected the combination of di (2-ethylhexyl) phosphoric acid (DEPA) and trioctylphosphine oxide (TOPO) as the most suitable. The flowscheme of the process is included

Uranium: War, Energy and the Rock That Shaped the World; Uranium: la biographie

Energy Technology Data Exchange (ETDEWEB)

Zoellner, T.

2009-07-01

Having traveled extensively through the savannah of Africa, the mountains of Eastern Europe, and the deserts of Utah, the author delves into the complex science, politics and history of uranium, which presents the best and worst of mankind: the capacity for scientific progress and political genius; the capacity for nihilism, exploitation, and terror. Because the author covers so much ground, from the discovery of radioactivity, through the development of the atomic bomb, he does not go into great depth on any one topic. Nonetheless, he paints vivid pictures of uranium's impact, including forced labor in Soviet mines and lucky prospectors who struck it rich in harsh environments, the spread of uranium smuggling, as well as an explanation of why it was absurd to claim that Saddam Hussein was attempting to purchase significant quantities of uranium from Niger. The only shortcoming is the author's omission of the issue of radioactive wastes generated by nuclear power. The author knows well what uranium looks like, why peril pulses in its every atom, and how scientists exploit its nuclear volatility. The drama is found in the weaponry uranium has spawned as demonstrated at Hiroshima and Nagasaki. In pursuit of this raw power, the U.S. let Navajos die extracting needed ore and let southwestern cities sicken beneath clouds from reckless testing. The Soviet Union sentenced tens of thousands to lethal gulag mines. Israel diverted ore through deception on the high seas. Pakistan stole European refining technology. Alive with devious personalities, the author's narrative ultimately exposes the frightening vulnerability of a world with too many sources of a dangerous substance and too little wisdom to control it

Uranium hydrogeochemical and stream sediment reconnaissance of the Gillette NTMS quadrangle, Wyoming, including concentrations of forty-two additional elements

International Nuclear Information System (INIS)

Warren, R.G.; George, W.E.; Minor, M.M.; Simi, O.R.; Talcott, C.L.; Hensley, W.K.; Cheadle, J.M. III.

1980-08-01

During 1976 and 1977, 752 water and 843 sediment samples were collected from 1419 locations within the 17 700-km 2 area of the Gillette quadrangle, Wyoming. Water samples were collected primarily from wells, and also from springs, ponds, and streams; sediment samples were collected primarily from stream channels, and also from springs and ponds. Each water sample was analyzed for uranium and each sediment sample was analyzed for 43 elements, including uranium and thorium. Uranium concentrations in water samples range from below the detection limit of 0.02 to 212.20 ppB and have a median of 1.10 ppB. The highest background uranium concentrations, as well as the highest individual uranium values, are in areas where favorable host units for uranium mineralization crop out. These units are the Wasatch and Fort Union formations in the Powder River Basin and the Inyan Kara group in the Black Hills. Uranium concentrations in sediment samples range from 0.64 to 29.83 ppM and have a median of 3.24 ppM. Background uranium concentrations are strongly controlled by the exposed geologic unit, and range from 4 to 8 ppM for the Cretaceous Colorado group to 1 to 3 ppM for the Triassic and Paleozoic units exposed in the Black Hills. Several areas where the Wasatch and Fort Union formations are exposed exhibit uranium concentrations in sediment samples that are slightly, but distinctly, above background values for these units. All of these areas are also associated with notably high uranium concentrations in water samples. Because epigenetic uranium mineralization in economically important areas can exhibit a similar geochemical signature, these areas within the Gillette quadrangle should be further examined for the possible presence of uranium mineralization

Hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to gamma radiation and depleted uranium singly and in combination

Energy Technology Data Exchange (ETDEWEB)

Song, You, E-mail: yso@niva.no [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway); Salbu, Brit; Teien, Hans-Christian [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Evensen, Øystein [Norwegian University of Life Sciences (NMBU), Department of Basic Sciences and Aquatic Medicine, P.O. Box 8146 Dep., N-0033 Oslo (Norway); Lind, Ole Christian [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Rosseland, Bjørn Olav [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian University of Life Sciences (NMBU), Department of Ecology and Natural Resource Management (INA), P.O. Box 5003, N-1432 Ås (Norway); and others

2016-08-15

Radionuclides are a special group of substances posing both radiological and chemical hazards to organisms. As a preliminary approach to understand the combined effects of radionuclides, exposure studies were designed using gamma radiation (Gamma) and depleted uranium (DU) as stressors, representing a combination of radiological (radiation) and chemical (metal) exposure. Juvenile Atlantic salmon (Salmo salar) were exposed to 70 mGy external Gamma dose delivered over the first 5 h of a 48 h period (14 mGy/h), 0.25 mg/L DU were exposed continuously for 48 h and the combination of the two stressors (Combi). Water and tissue concentrations of U were determined to assess the exposure quality and DU bioaccumulation. Hepatic gene expression changes were determined using microarrays in combination with quantitative real-time reverse transcription polymerase chain reaction (qPCR). Effects at the higher physiological levels were determined as plasma glucose (general stress) and hepatic histological changes. The results show that bioaccumulation of DU was observed after both single DU and the combined exposure. Global transcriptional analysis showed that 3122, 2303 and 3460 differentially expressed genes (DEGs) were significantly regulated by exposure to gamma, DU and Combi, respectively. Among these, 349 genes were commonly regulated by all treatments, while the majority was found to be treatment-specific. Functional analysis of DEGs revealed that the stressors displayed similar mode of action (MoA) across treatments such as induction of oxidative stress, DNA damage and disturbance of oxidative phosphorylation, but also stressor-specific mechanisms such as cellular stress and injury, metabolic disorder, programmed cell death, immune response. No changes in plasma glucose level as an indicator of general stress and hepatic histological changes were observed. Although no direct linkage was successfully established between molecular responses and adverse effects at the organism

Hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to gamma radiation and depleted uranium singly and in combination

International Nuclear Information System (INIS)

Song, You; Salbu, Brit; Teien, Hans-Christian; Evensen, Øystein; Lind, Ole Christian; Rosseland, Bjørn Olav

2016-01-01

Radionuclides are a special group of substances posing both radiological and chemical hazards to organisms. As a preliminary approach to understand the combined effects of radionuclides, exposure studies were designed using gamma radiation (Gamma) and depleted uranium (DU) as stressors, representing a combination of radiological (radiation) and chemical (metal) exposure. Juvenile Atlantic salmon (Salmo salar) were exposed to 70 mGy external Gamma dose delivered over the first 5 h of a 48 h period (14 mGy/h), 0.25 mg/L DU were exposed continuously for 48 h and the combination of the two stressors (Combi). Water and tissue concentrations of U were determined to assess the exposure quality and DU bioaccumulation. Hepatic gene expression changes were determined using microarrays in combination with quantitative real-time reverse transcription polymerase chain reaction (qPCR). Effects at the higher physiological levels were determined as plasma glucose (general stress) and hepatic histological changes. The results show that bioaccumulation of DU was observed after both single DU and the combined exposure. Global transcriptional analysis showed that 3122, 2303 and 3460 differentially expressed genes (DEGs) were significantly regulated by exposure to gamma, DU and Combi, respectively. Among these, 349 genes were commonly regulated by all treatments, while the majority was found to be treatment-specific. Functional analysis of DEGs revealed that the stressors displayed similar mode of action (MoA) across treatments such as induction of oxidative stress, DNA damage and disturbance of oxidative phosphorylation, but also stressor-specific mechanisms such as cellular stress and injury, metabolic disorder, programmed cell death, immune response. No changes in plasma glucose level as an indicator of general stress and hepatic histological changes were observed. Although no direct linkage was successfully established between molecular responses and adverse effects at the organism

Internal dosimetric evaluation due to uranium aerosols

International Nuclear Information System (INIS)

Garcia Aguilar Juan; Delgado Avila Gustavo

1991-01-01

The present work has like object to carry out the internal dosimetric evaluation to the occupationally exposed personnel, due to the inhalation of aerosols of natural uranium and enriched in the pilot plant of nuclear fuel production of the National Institute of Nuclear Research

Standard test method for determination of uranium or plutonium isotopic composition or concentration by the total evaporation method using a thermal ionization mass spectrometer

CERN Document Server

American Society for Testing and Materials. Philadelphia

2007-01-01

1.1 This method describes the determination of the isotopic composition and/or the concentration of uranium and plutonium as nitrate solutions by the thermal ionization mass spectrometric (TIMS) total evaporation method. Purified uranium or plutonium nitrate solutions are loaded onto a degassed metal filament and placed in the mass spectrometer. Under computer control, ion currents are generated by heating of the filament(s). The ion beams are continually measured until the sample is exhausted. The measured ion currents are integrated over the course of the run, and normalized to a reference isotope ion current to yield isotopic ratios. 1.2 In principle, the total evaporation method should yield isotopic ratios that do not require mass bias correction. In practice, some samples may require this bias correction. When compared to the conventional TIMS method, the total evaporation method is approximately two times faster, improves precision from two to four fold, and utilizes smaller sample sizes. 1.3 The tot...

Triglycerides, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol in rats exposed to premium motor spirit fumes.

Science.gov (United States)

Aberare, Ogbevire L; Okuonghae, Patrick; Mukoro, Nathaniel; Dirisu, John O; Osazuwa, Favour; Odigie, Elvis; Omoregie, Richard

2011-06-01

Deliberate and regular exposure to premium motor spirit fumes is common and could be a risk factor for liver disease in those who are occupationally exposed. A possible association between premium motor spirit fumes and plasma levels of triglyceride, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol using a rodent model could provide new insights in the pathology of diseases where cellular dysfunction is an established risk factor. The aim of this study was to evaluate the possible effect of premium motor spirit fumes on lipids and lipoproteins in workers occupationally exposed to premium motor spirit fumes using rodent model. Twenty-five Wister albino rats (of both sexes) were used for this study between the 4(th) of August and 7(th) of September, 2010. The rats were divided into five groups of five rats each. Group 1 rats were not exposed to premium motor spirit fumes (control group), group 2 rats were exposed for 1 hour daily, group 3 for 3 hours daily, group 4 for 5 hours daily and group 5 for 7 hours daily. The experiment lasted for a period of 4 weeks. Blood samples obtained from all the groups after 4 weeks of exposure were used for the estimation of plasma levels of triglyceride, total cholesterol, high density lipoprotein- cholesterol and low density lipoprotein- cholesterol. Results showed significant increase in means of plasma total cholesterol and low density lipoprotein levels (P<0.05). The mean triglyceride and total body weight were significantly lower (P<0.05) in the exposed group when compared with the unexposed. The plasma level of high density lipoprotein, the ratio of low density lipoprotein to high density lipoprotein and the ratio of total cholesterol to high density lipoprotein did not differ significantly in exposed subjects when compared with the control group. These results showed that frequent exposure to petrol fumes may be highly deleterious to the liver cells.

The United States Transuranium and Uranium Registries: overview and recent progress

International Nuclear Information System (INIS)

Kathren, R.L.

1989-01-01

This paper describes the organisation, activities and recent scientific accomplishments of the United States Transuranium and Uranium Registries. Through voluntary donations of tissue obtained at autopsies, the Registries carry out studies of the concentration, distribution and biokinetics of actinides in occupationally exposed persons. Findings from tissue analyses from more than 200 autopsies include the following: a greater proportion of the americium intake, as compared with plutonium, is found in the skeleton; the half-time of americium in liver is significantly shorter than that of plutonium; the concentration of actinide in the skeleton is inversely proportional to the calcium and ash content of the bone; only a small percentage of the total skeletal deposition of plutonium is found in the marrow, implying a smaller risk from irradiation of the marrow relative to the bone surfaces; estimates of plutonium body burden made from urinalysis typically exceed those made from autopsy data; pathologists are unable to discriminate between a group of uranium workers and persons without known occupational exposure on the basis of evaluation of microscopic kidney slides; the skeleton is an important long-term depot for uranium and its fractional uptake by both skeleton and kidney may be greater than indicated by current models. These and other findings and current studies are discussed in depth. (author)

Evaluation of the toxic effect on zebrafish (Danio rerio) exposed to uranium mill tailings leaching solution

International Nuclear Information System (INIS)

Fang Geng; Nan Hu; Ji-Fang Zheng; Cheng-Lei Wang; Xin Chen; Jia Yu; De-Xin Ding

2012-01-01

The objective of this study was to evaluate the potential ecological danger and toxic effect of uranium mill tailings leaching solution (UMTLS) on aquatic animals. UMTLS was identified to contain two radioactive elements, nine heavy metal elements, and five non-metallic materials. The acute toxicity test indicated that the 1, 12, 24, 48, 72, 96 h LC 50 values of UMTLS to the zebrafish were 12.1, 7.1, 4.4, 3.8, 3.4, and 2.9%, respectively. In sub-lethal toxicity tests, superoxide dismutase, catalase, Na + -K + -ATPase activities, and malondialdehyde content were respectively determined and analyzed in the zebrafish gill, gonad, muscle, and liver after exposed to four different concentration levels of UMTLS for 7 and 14 days, respectively. The result showed that the most sensitivity of the antioxidant system in zebrafish tissues in UMTLS was gill, and then decreased in gonad, muscle and liver respectively. Na + -K + -ATPase activity in the liver and gonad may be considered as a reference biomarker of UMTLS stress. The data in this study may be valuable that the toxicity of such as the leaching solution of potentially hazardous material was compared with that of each constituent. (author)

Formation of corrosion-resistant oxide film on uranium

International Nuclear Information System (INIS)

Petit, G.S.

1976-01-01

A vacuum heat-treatment method was developed for coating metallic uranium with an adherent protective film of uranium oxide. The film is prepared by vacuum heat-treating the metallic uranium at 625 0 C for 1 h while controlling the amount of oxygen being metered into the furnace. Uranium coupons with the protective film were exposed for several hundred hours in a corrosion test bath at 95 0 C and 100 percent RH without corroding. Film thicknesses ranging from 5 to 25 μm (0.0002 to 0.001 in.) were prepared and corrosion tested; the film thickness can be controlled to less than +-2.5 μm (+-0.0001 in.). The oxide film is hard, nonwetting, and very adherent. The resulting surface finish of the metal is equivalent to that of the original finish. The advantages of the oxide films over other protective coatings are given. 12 fig

Enhanced Uranium Immobilization and Reduction by Geobacter sulfurreducens Biofilms

Science.gov (United States)

Cologgi, Dena L.; Speers, Allison M.; Bullard, Blair A.; Kelly, Shelly D.

2014-01-01

Biofilms formed by dissimilatory metal reducers are of interest to develop permeable biobarriers for the immobilization of soluble contaminants such as uranium. Here we show that biofilms of the model uranium-reducing bacterium Geobacter sulfurreducens immobilized substantially more U(VI) than planktonic cells and did so for longer periods of time, reductively precipitating it to a mononuclear U(IV) phase involving carbon ligands. The biofilms also tolerated high and otherwise toxic concentrations (up to 5 mM) of uranium, consistent with a respiratory strategy that also protected the cells from uranium toxicity. The enhanced ability of the biofilms to immobilize uranium correlated only partially with the biofilm biomass and thickness and depended greatly on the area of the biofilm exposed to the soluble contaminant. In contrast, uranium reduction depended on the expression of Geobacter conductive pili and, to a lesser extent, on the presence of the c cytochrome OmcZ in the biofilm matrix. The results support a model in which the electroactive biofilm matrix immobilizes and reduces the uranium in the top stratum. This mechanism prevents the permeation and mineralization of uranium in the cell envelope, thereby preserving essential cellular functions and enhancing the catalytic capacity of Geobacter cells to reduce uranium. Hence, the biofilms provide cells with a physically and chemically protected environment for the sustained immobilization and reduction of uranium that is of interest for the development of improved strategies for the in situ bioremediation of environments impacted by uranium contamination. PMID:25128347

Mobility of elevated levels of uranium in the environment

International Nuclear Information System (INIS)

Miera, F.R. Jr.; Hanson, W.C.; Gladney, E.S.; Jose, P.

1980-01-01

Studies of the long-term consequences of exposing terrestrial ecosystems to aged deposits of natural and depleted uranium at Los Alamos Scientific Laboratory (LASL) have been conducted over the past 3 years. The E-F explosive testing site at LASL was selected for intensive study of uranium redistribution during its 24-year use. The highest surface-soil (0 to 2.5 cm) uranium concentrations occurred 0 to 10 m from the detonation point and average 4500 μg/g. Concentrations in surface soil 50 and 200 m from the detonation point were generally less than 15% of that value. The uranium distribution to 30-cm depths for the 0- to 50-m distant sampling locations and to 10-cm depths at 50- to 200-m sampling distances showed significant penetration into the soil profile. Ratios of plant/soil uranium concentrations varied from 0.05 to 0.08. Internal tissues from two species of small mammals had tissue/soil ratios of 10 -3 and 10 -4

Lung cancer in uranium miners: A tissue resource and pilot study. Progress report, September 25, 1992 - May 31, 1993

International Nuclear Information System (INIS)

Samet, J.M.

1993-05-01

This project involves two related activities directed toward understanding respiratory carcinogenesis in radon-exposed former uranium miners. The first activity involves a continuation of the tissue resource of lung cancer cases from former underground uranium miners and comparison cases from non-miners. The second activity is a pilot study for a proposed longitudinal study of respiratory carcinogenesis in former uranium miners. The objectives are to facilitate the investigation of molecular changes in radon exposed lung cancer cases and to develop methods for prospectively studying clinical, cytologic, cytogenetic, and molecular changes in the multi-event process of respiratory carcinogenesis, and to assess the feasibility of recruiting former uranium miners into a longitudinal study that collects multiple biologic specimens

Brazilian uranium reserves

International Nuclear Information System (INIS)

Marques, J.P.M.

1981-01-01

Due to a growing demand of electric power to support Brasil's development, the use of nuclear energy will be indispensable. The nuclear fuel cycle for the production of energy, starts with the uranium exploration. The work performed in this field led to the discovery of several deposits in the country, which to-date totalize a reserve of 236,300t of U 308 , ranking Brazil in the 6th place among the nations of the western world holding uranium reserves. (Author) [pt

Use of vacuum in processing of uranium

International Nuclear Information System (INIS)

Saify, M.T.; Rai, C.B.; Singh, S.P.; Singh, R.P.

2003-01-01

Full text: Natural uranium in the form of metal and alloys with suitable heat treatment are being used as fuel in research and some of the power reactors. The fuel is required to satisfy the purity specification from the criteria of neutron economy, corrosion resistance and fabricability. Uranium and its alloys fall under the category of reactive materials. They readily react with atmospheric air to form oxides. If molten uranium is exposed to atmosphere, it reacts violently with atmospheric gases and moisture, leading to explosion in extreme cases. Hence, protective inert atmosphere or high vacuum is required in processing of the materials especially during the melting and casting operation. Vacuum is preferred for melting and remelting of metals and alloys to remove the gaseous and high volatile impurities, to improve the mechanical properties of the material. Also, under vacuum sound castings are produced for further processing by mechanical working or use in casting forms. The addition of reactive alloying elements in uranium is efficiently carried out under vacuum. The paper highlights vacuum systems deployed and applications of vacuum in various operations involved in the processing of uranium and its alloys

Copper Mountain, Wyoming, intermediate-grade uranium resource assessment project. Final report. National Uranium Resource Evaluation

International Nuclear Information System (INIS)

Madson, M.E.; Ludlam, J.R.; Fukui, L.M.

1982-11-01

Intermediate-grade uranium resources were delineated and estimated for Eocene and Precambrian host rock environments in the 39.64 mi 2 Copper Mountain, Wyoming, assessment area. Geologic reconnaissance and geochemical, geophysical, petrologic, borehole, and structural data were interpreted and used to develop a genetic model for uranium mineralization in these environments. Development of a structural scoring system and application of computer graphics in a high-confidence control area established the basis for estimations of uranium resources in the total assessment area. 8 figures, 5 tables

Hydrothermal uranium vein deposits in Marysvale volcanic field, Utah

International Nuclear Information System (INIS)

Rasmussen, J.D.; Cunningham, C.G.; Steven, T.A.; Rye, R.O.; Romberger, S.B.

1984-01-01

Hydrothermal uranium veins are exposed over a 300 m (980 ft) vertical range in mines of the Central Mining area, near Marysvale, Utah. They cut 23 Ma quartz monzonite, 21 Ma granite, and 19 Ma rhyolite ash-flow tuff. The veins formed 18-19 Ma, in an area 1 km (0.6 mi) across, above the center of a composite magma chamber at least 12 x 6 km across that fed a sequence of 21-14 Ma hypabyssal granitic stocks, and rhyolitic lava flows, ash-flow tuffs, and volcanic domes. Intrusive pressure uplifted and fractured the roof; molybdenite-bearing, uranium-rich glassy dikes were intruded; and a breccia pipe and uranium-bearing veins were formed. The veins appear to have been deposited near the surface above a concealed rhyolite stock, where they filled high-angle fault zones and flat-lying to concave-downward pull-apart fractures. Low pH and fO 2 hydrothermal fluids at temperatures near 200 0 C (392 0 F) permeated the fractured rocks; these fluids were rich in fluorine and potassium, and contained uranium as uranous-fluoride complexes. Fluid-wall rock interaction increased fluid pH, causing precipitation of uranium minerals. At the deepest exposed levels, wall rocks were altered to kaolinite and sericite, and uraninite, coffinite, jordisite, fluorite, molybdenite, quartz, and pyrite (with delta 34 S near zero per mil) were deposited. The fluids were progressively oxidized higher in the system; iron in the wall rocks was oxidized to hematite, and sooty uraninite and umohoite were deposited

Interpreting faecal analysis results for monitoring exposure to uranium

International Nuclear Information System (INIS)

Berard, P.; Rongier, E.; Faure, M.L.; Auriol, B.; Estrabaud, M.; Mazeyrat, C.

1996-01-01

Radiotoxicological monitoring of workers exposed to non-transferable forms of uranium requires six-monthly examinations. These examinations are prescribed according to the kind of product manipulated and tO the industrial risk attached to the workplace. The range of examinations that are useful for this kind of monitoring includes whole body counting examinations, urine analyses and in-line faecal sampling: whole body examinations, which are fundamental to monitoring, provide a lung retention value. However, the detection limit of lung examinations is not low enough for chronic operational monitoring; urine examinations are extremely sensitive to alpha activity (1 mBq per isotope) but the fraction detected in the urine after incorporation by inhalation is very small; in-line 24-hour faecal sampling allows avoiding any workplace exclusion. The authors intend to present their experience acquired over a six year period in the field of systematic faecal examinations after chronic inhalation of the different uranium compounds. They also present results of a study carried out to determine normal uranium concentrations in the faeces of a non-exposed population, the uranium content in drinking waters and the consequences on faecal excretion. Establishing the isotopic content of uranium in the faeces makes it possible to determine practical investigation levels for occupational monitoring. Even if faecal sampling may be critically perceived by the personnel, the authors' experience highlights the value of this kind of analysis which allows to track down the industrial reality of the exposure. Internal dosimetry calculations cannot, however, be carried out, because the physical parameters of the inhaled aerosols are not always known. (author)

Groundwater uranium and cancer incidence in South Carolina

Science.gov (United States)

Wagner, Sara E.; Burch, James B.; Bottai, Matteo; Puett, Robin; Porter, Dwayne; Bolick-Aldrich, Susan; Temples, Tom; Wilkerson, Rebecca C.; Vena, John E.; Hébert, James R.

2012-01-01

Objective This ecologic study tested the hypothesis that census tracts with elevated groundwater uranium and more frequent groundwater use have increased cancer incidence. Methods Data sources included: incident total, leukemia, prostate, breast, colorectal, lung, kidney, and bladder cancers (1996–2005, SC Central Cancer Registry); demographic and groundwater use (1990 US Census); and groundwater uranium concentrations (n = 4,600, from existing federal and state databases). Kriging was used to predict average uranium concentrations within tracts. The relationship between uranium and standardized cancer incidence ratios was modeled among tracts with substantial groundwater use via linear or semiparametric regression, with and without stratification by the proportion of African Americans in each area. Results A total of 134,685 cancer cases were evaluated. Tracts with ≥50% groundwater use and uranium concentrations in the upper quartile had increased risks for colorectal, breast, kidney, prostate, and total cancer compared to referent tracts. Some of these relationships were more likely to be observed among tracts populated primarily by African Americans. Conclusion SC regions with elevated groundwater uranium and more groundwater use may have an increased incidence of certain cancers, although additional research is needed since the design precluded adjustment for race or other predictive factors at the individual level. PMID:21080052

Environmental fate of depleted uranium at three sites contaminated during the balkan conflict

International Nuclear Information System (INIS)

Radenkovic, M.; Joksic, J.; Todorovic, D.; Kovacevic, M.

2006-01-01

A study on depleted uranium fate in the sites contaminated during the 1999 war conflict in Serbia was conducted in phases until the clean up activities were completed. The ammunition remains found at the locations in the surface soil were collected in the first phase during the radiation survey of the affected areas. The most of depleted uranium penetrators left buried deep into the ground exposed to the weathering and corrosion processes. The contamination level in the air, water, soil and bio -indicators was controlled all the time by routine gamma and alpha spectrometry measurements. Depleted uranium migration was studied through the soil profile surrounding the penetrator during the 2001 at the Bratoselce location showing the contamination level fall to the 1% of its value at approximately 15 cm distance to the source. The samples taken from the soil layers at different distances in the profile are subjected to a modified Tessiers five-step sequential extraction procedure. The uranium and heavy metals contents were determined in the obtained fractions. Results have specified carbonates and iron hydrous-oxides as the most probable substrates for uranium physical/chemical associations formed in the soil for the time elapsed. A very strong dependence of substrate onto contamination level was found. The correlation of uranium and other heavy metals was obtained. The 234 U/ 238 U and 235 U/ 238 U ratios are determined in extracts by alpha spectrometry after appropriate radiochemical separation procedure and thin alpha sources electroplating. The analysis has shown the share of depleted in total uranium content in exchangeable, carbonate, hydrous or crystalline iron/manganese, organic and residue phases indicating the bioavailability of depleted uranium present in the soil. The results are discussed related to detailed geochemical analysis of the particular soil type common for this region. Depleted uranium content in soil samples taken at the locations after the

Tumor risk and nephrotoxicity in case of uranium exposure; Tumorrisiko und Nephrotoxizitaet bei Uranexposition

Energy Technology Data Exchange (ETDEWEB)

Stammler, Leonhard

2017-05-18

The thesis was focused on the health hazards of chronic uranium exposure with respect to tumor evolution and nephritic lesions. Mortality rates and incidence rates were determined for different tumor types by meta-analysis of existing studies including uranium mine workers, soldiers exposed to uranium ammunition and exposure due to uranium containing drinking water. The results did not show a significant increase of mortality or incidence rates. Possible errors or deficiencies of the evaluated studies are discussed. Increased beta-2-microglobulin values might indicate the possibility of nephritic lesions.

Concerted Uranium Research in Europe (CURE): toward a collaborative project integrating dosimetry, epidemiology and radiobiology to study the effects of occupational uranium exposure.

Science.gov (United States)

Laurent, Olivier; Gomolka, Maria; Haylock, Richard; Blanchardon, Eric; Giussani, Augusto; Atkinson, Will; Baatout, Sarah; Bingham, Derek; Cardis, Elisabeth; Hall, Janet; Tomasek, Ladislav; Ancelet, Sophie; Badie, Christophe; Bethel, Gary; Bertho, Jean-Marc; Bouet, Ségolène; Bull, Richard; Challeton-de Vathaire, Cécile; Cockerill, Rupert; Davesne, Estelle; Ebrahimian, Teni; Engels, Hilde; Gillies, Michael; Grellier, James; Grison, Stephane; Gueguen, Yann; Hornhardt, Sabine; Ibanez, Chrystelle; Kabacik, Sylwia; Kotik, Lukas; Kreuzer, Michaela; Lebacq, Anne Laure; Marsh, James; Nosske, Dietmar; O'Hagan, Jackie; Pernot, Eileen; Puncher, Matthew; Rage, Estelle; Riddell, Tony; Roy, Laurence; Samson, Eric; Souidi, Maamar; Turner, Michelle C; Zhivin, Sergey; Laurier, Dominique

2016-06-01

The potential health impacts of chronic exposures to uranium, as they occur in occupational settings, are not well characterized. Most epidemiological studies have been limited by small sample sizes, and a lack of harmonization of methods used to quantify radiation doses resulting from uranium exposure. Experimental studies have shown that uranium has biological effects, but their implications for human health are not clear. New studies that would combine the strengths of large, well-designed epidemiological datasets with those of state-of-the-art biological methods would help improve the characterization of the biological and health effects of occupational uranium exposure. The aim of the European Commission concerted action CURE (Concerted Uranium Research in Europe) was to develop protocols for such a future collaborative research project, in which dosimetry, epidemiology and biology would be integrated to better characterize the effects of occupational uranium exposure. These protocols were developed from existing European cohorts of workers exposed to uranium together with expertise in epidemiology, biology and dosimetry of CURE partner institutions. The preparatory work of CURE should allow a large scale collaborative project to be launched, in order to better characterize the effects of uranium exposure and more generally of alpha particles and low doses of ionizing radiation.

Polarography applied to the determination of uranium oxide composition; Application de la polarographie a la determination de la composition d'oxydes d'uranium

Energy Technology Data Exchange (ETDEWEB)

Nens, C; Canton, C; Molina, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires, Departement de Chimie, Services d' Etudes Chimiques et d' Analyse, Service d' Etudes Analytiques, Section de Chimie Analytique du Plutonium et d' Electroanalyse

1967-03-01

An analytical method based on conventional polarography has been developed, for the determination of the O/U ratio in uranium oxides. The dissolution of the samples is effected by means of molten ammonium bifluoride. After a transfer to aqueous solution, polarography is used to determine the oxide composition by measurement of both the hexavalent and the total uranium. (author) [French] Une methode d'analyse utilisamt la polarographie conventionnelle a ete mise au point pour la determination du rapport O/U dans les oxydes d'uranium. La mise en solution des echgantillons est realisee en milieu de bifluorure d'ammonium fondu. Apres passage en salution aqueuse, la polarographie permet d'atteindre la composition de l'oxyde par determination de l'uranium hexavalent et de l'uranium total. (auteur)

Uranium Task Force final report

International Nuclear Information System (INIS)

1991-03-01

Site-specific data on the management of uranium of 17 facilities have been assembled and analyzed to develop a comprehensive report on uranium processes, treatment, storage, and disposal on a Department of Energy-wide basis. By integrating a variety of waste generation sources, treatment processes, storage facilities, and disposal options, this waste management system study aims to effectively characterize and evaluate the performance and effectiveness of the total Department of Energy system for the management of uranium, as well as the individual sites. 7 refs., 7 figs., 2 tabs

Uranium geochemistry on the Amazon shelf: Evidence for uranium release from bottom sediments

International Nuclear Information System (INIS)

McKee, B.A.; DeMaster, D.J.; Nittrouer, C.A.

1987-01-01

In Amazon-shelf waters, as salinity increases to 36.5 x 10 -3 , dissolved uranium activities increase to a maximum of 4.60 dpm 1 -1 . This value is much higher than the open-ocean value (2.50 dpm 1 -1 ), indicating a source of dissolved uranium to shelf waters in addition to that supplied from open-ocean and riverine waters. Uranium activities are much lower for surface sediments in the Amazon-shelf sea bed (mean: 0.69 ± .09 dpm g -1 ) than for suspended sediments in the Amazon river (1.82 dpm g -1 ). Data suggest that the loss of particulate uranium from riverine sediments is probably the result of uranium desorption from the ferric-oxyhydroxide coatings on sediment particles, and/or uranium release by mobilization of the ferric oxyhydroxides. The total flux of dissolved 238 U from the Amazon shelf (about 1.2 x 10 15 dpm yr -1 ) constitutes about 15% of uranium input to the world ocean, commensurate to the Amazon River's contribution to world river-water discharge. Measurement of only the riverine flux of dissolved 238 U underestimates, by a factor of about 5, the flux of dissolved 238 U from the Amazon shelf to the open ocean

Uranium quantification in semen by inductively coupled plasma mass spectrometry

Science.gov (United States)

Todorov, Todor I.; Ejnik, John W.; Guandalini, Gustavo S.; Xu, Hanna; Hoover, Dennis; Anderson, Larry W.; Squibb, Katherine; McDiarmid, Melissa A.; Centeno, Jose A.

2013-01-01

In this study we report uranium analysis for human semen samples. Uranium quantification was performed by inductively coupled plasma mass spectrometry. No additives, such as chymotrypsin or bovine serum albumin, were used for semen liquefaction, as they showed significant uranium content. For method validation we spiked 2 g aliquots of pooled control semen at three different levels of uranium: low at 5 pg/g, medium at 50 pg/g, and high at 1000 pg/g. The detection limit was determined to be 0.8 pg/g uranium in human semen. The data reproduced within 1.4–7% RSD and spike recoveries were 97–100%. The uranium level of the unspiked, pooled control semen was 2.9 pg/g of semen (n = 10). In addition six semen samples from a cohort of Veterans exposed to depleted uranium (DU) in the 1991 Gulf War were analyzed with no knowledge of their exposure history. Uranium levels in the Veterans’ semen samples ranged from undetectable (<0.8 pg/g) to 3350 pg/g. This wide concentration range for uranium in semen is consistent with known differences in current DU body burdens in these individuals, some of whom have retained embedded DU fragments.

World uranium resources

International Nuclear Information System (INIS)

Deffeyes, K.S.; MacGregor, I.D.

1980-01-01

To estimate the total resource availability of uranium, the authors' approach has been to ask whether the distribution of uranium in the earth's crust can be reasonably approximated by a bell-shaped log-normal curve. In addition they have asked whether the uranium deposits actually mined appear to be a portion of the high-grade tail, or ascending slope, of the distribution. This approach preserves what they feel are the two most important guiding principles of Hubbert's work, for petroleum, namely recognizing the geological framework that contains the deposits of interest and examining the industry's historical record of discovering those deposits. Their findings, published recently in the form of a book-length report prepared for the US Department of Energy, suggest that for uranium the crustal-distribution model and the mining-history model can be brought together in a consistent picture. In brief, they conclude that both sets of data can be described by a single log-normal curve, the smoothly ascending slope of which indicates approximately a 300-fold increase in the amount of uranium recoverable for each tenfold decrease in ore grade. This conclusion has important implications for the future availability of uranium. They hasten to add, however, that this is only an approximative argument; no rigorous statistical basis exists for expecting a log-normal distribution. They continue, pointing out the enormously complex range of geochemical behavior of uranium - and its wide variety of different binds of economic deposit. Their case study, supported by US mining records, indicates that the supply of uranium will not be a limiting factor in the development of nuclear power

Heap leaching for uranium

International Nuclear Information System (INIS)

1988-01-01

Denison Mines Ltd. is using two bacterial leaching processes to combat the high cost of extracting uranium from low grade ore in thin reefs. Both processes use thiobacillus ferro-oxidans, a bacterium that employs the oxidation of ferrous iron and sulphur as its source of energy for growth. The first method is flood leaching, in which ore is subjected to successive flood, drain and rest cycles. The second, trickle leaching, uses sprinklers to douse the broken muck continuously with leaching solution. In areas where grades are too low to justify the expense of hauling the ore to the surface, the company is using this biological process underground to recover uranium. In 1987 Denison recovered 840 000 lb of uranium through bacterial heap leaching. It plans to have biological in-place leaching contribute 25% of the total uranium production by 1990. (fig.)

Uranium ore processing minimizing reagent losses

International Nuclear Information System (INIS)

Shaogiang, Chen; Moret, J.; Lyaudet, G.

1989-01-01

The uranium ore is treated by sodium carbonates and the solution is divided in two parts: a production solution which is decarbonated by an acid before uranium precipitation with sodium hydroxide and a recycling solution directly treated by sodium hydroxide for precipitation of about 85% of uranium and total transformation of sodium bicarbonate into sodium carbonate, the quantity of sodium hydroxide used on the recycling solution brings sodium ions required for attack of the ore [fr

Chemometric approach for prediction of uranium pathways in the soil

International Nuclear Information System (INIS)

Stojanovic, Mirjana; Nihajlovic, Marija; Petrovic, Jelena; Petrovic, Marija; Sostaric, Tanja; Milojkovic, Jelena; Pezo, Lato

2014-01-01

Understanding the effect of soil parameters (pH, Eh and organic and inorganic ligands availability) on uranium mobility under different geochemical conditions is fundamental for reliable prediction of its behaviour and fate in the environment. In this study, the impact of total and available phosphorus content, humus and acidity of Serbian agricultural soils on the content of total and available uranium were evaluated by Response Surface Methodology (RSM), second order polynomial regression models (SOPs) and artificial neural networks (ANNs). The performance of ANNs was compared with the performance of SOPs and experimental results. SOPs showed high coefficients of determination (0.785-0.956), while ANN model performed high prediction accuracy: 0.8893-0.904. According to the results, total and available uranium content in the soil were mostly affected by pH, statistically significant at p < 0.05 level. For the same responses the total phosphorus was found to be also very influential, statistically significant at p < 0.05 and p < 0.10 levels. The impact of available phosphorus and humus was much more influential on total and available uranium content, compared to total phosphorus content. Proposed chemometric approach will be very helpful in preserving the natural resources and practical application for risk assessment modeling of uranium environmental pathways.

Probabilistic estimates of US uranium supply

International Nuclear Information System (INIS)

Piepel, G.F.; Long, L.W.; McLaren, R.A.; Ford, C.E.

1981-02-01

This report develops and presents probabilistic estimates of total US uranium supply. The word supply is used in the broad sense that both uranium quantity and cost are of interest. Cost implies minimum acceptable selling price rather than market price. Specifically, four types of probability distributions are developed: (1) quantity of US uranium; (2) cost of US uranium; (3) quantity of US uranium available at or below a certain cost; and (4) cost of US uranium given a certain consumption. In this report, uranium refers to recoverable U 3 O 8 (endowment adjusted for mining recovery and milling losses) occurring in both reserve and potential deposits meeting minimum size requirements with minimum grade above 0.01%. Cost includes operating and capital costs, taxes, profit, and cost capital. This definition of cost is often used to better denote this meaning. This definition of cost is contrasted with forward costs, that exclude sunk costs, taxes, and return on investment. Consumption refers to uranium that has been used from the current time to any point in the future. Uranium quantity and consumption are expressed in short tons, while full recovery costs are stated in constant 1980 dollars per pound

Uranium determination in water

International Nuclear Information System (INIS)

Prudenzo, E.J.; Puga, Maria J.; Cerchietti, Maria L.R.; Arguelles, Maria G.

2005-01-01

In our laboratory, a procedure has been assessed to determine uranium content of water in normal situations. The method proposed without sample pre-treatment, is simple and rapid. Uranium mass is measured by fluorimetry. For calculation of detection limit (Ld) and quantification level (Lq) we used blank samples and the results were analyzed for different statistical test. The calculation of total propagated uncertainty and sources contribution on real samples are presented. (author)

On the distribution of uranium in hair: Non-destructive analysis using synchrotron radiation induced X-ray fluorescence microprobe techniques

Energy Technology Data Exchange (ETDEWEB)

Israelsson, A., E-mail: axel.israelsson@liu.se [Department of Medical and Health Sciences, Linköping University, 58183 Linköping (Sweden); Eriksson, M. [Swedish Radiation Safety Authority, 17116 Stockholm (Sweden); Pettersson, H.B.L. [Department of Radiation Physics, Linköping University, 58183 Linköping (Sweden); Department of Medical and Health Sciences, Linköping University, 58183 Linköping (Sweden)

2015-06-01

In the present study the distribution of uranium in single human hair shafts has been evaluated using two synchrotron radiation (SR) based micro X-ray fluorescence techniques; SR μ-XRF and confocal SR μ-XRF. The hair shafts originated from persons that have been exposed to elevated uranium concentrations. Two different groups have been studied, i) workers at a nuclear fuel fabrication factory, exposed mainly by inhalation and ii) owners of drilled bedrock wells exposed by ingestion of water. The measurements were carried out on the FLUO beamline at the synchrotron radiation facility ANKA, Karlsruhe. The experiment was optimized to detect U with a beam size of 6.8 μm × 3 μm beam focus allowing detection down to ppb levels of U in 10 s (SR μ-XRF setup) and 70 s (SR confocal μ-XRF setup) measurements. It was found that the uranium was present in a 10–15 μm peripheral layer of the hair shafts for both groups studied. Furthermore, potential external hair contamination was studied by scanning of unwashed hair shafts from the workers. Sites of very high uranium signal were identified as particles containing uranium. Such particles, were also seen in complementary analyses using variable pressure electron microscope coupled with energy dispersive X-ray analyzer (ESEM–EDX). However, the particles were not visible in washed hair shafts. These findings can further increase the understanding of uranium excretion in hair and its potential use as a biomonitor. - Highlights: • Uranium at the fg level was detectable and the uranium distribution in single hair shafts was derived. • The uranium is located peripherally on the shafts in what seems to be a layer of approximately 10-15 μm thickness. • Uranium bearing particles were found on hairs that had not been washed.

Uranium content in soils, vegetables, cereals and fruits

International Nuclear Information System (INIS)

Frindik, O.

1988-01-01

As compared to other vegetable samples, parsley leaves showed a much higher uranium content, presumably due to tightly adhering dust which could not be removed by washing. Uranium transfer factors from the soil to the plants were calculated; these factors always include the total uranium concentration and not only the 'soluble' uranium. As compared to U-238 the activity of U-234 is nearly always higher in vegetable samples, but lower in soil samples. (orig./HP) [de

Uranium Metal Analysis via Selective Dissolution

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Sinkov, Sergey I.; Schmidt, Andrew J.; Chenault, Jeffrey W.

2008-09-10

Uranium metal, which is present in sludge held in the Hanford Site K West Basin, can create hazardous hydrogen atmospheres during sludge handling, immobilization, or subsequent transport and storage operations by its oxidation/corrosion in water. A thorough knowledge of the uranium metal concentration in sludge therefore is essential to successful sludge management and waste process design. The goal of this work was to establish a rapid routine analytical method to determine uranium metal concentrations as low as 0.03 wt% in sludge even in the presence of up to 1000-fold higher total uranium concentrations (i.e., up to 30 wt% and more uranium) for samples to be taken during the upcoming sludge characterization campaign and in future analyses for sludge handling and processing. This report describes the experiments and results obtained in developing the selective dissolution technique to determine uranium metal concentration in K Basin sludge.

Depleted uranium instead of lead in munitions: the lesser evil.

Science.gov (United States)

Jargin, Sergei V

2014-03-01

Uranium has many similarities to lead in its exposure mechanisms, metabolism and target organs. However, lead is more toxic, which is reflected in the threshold limit values. The main potential hazard associated with depleted uranium is inhalation of the aerosols created when a projectile hits an armoured target. A person can be exposed to lead in similar ways. Accidental dangerous exposures can result from contact with both substances. Encountering uranium fragments is of minor significance because of the low penetration depth of alpha particles emitted by uranium: they are unable to penetrate even the superficial keratin layer of human skin. An additional cancer risk attributable to the uranium exposure might be significant only in case of prolonged contact of the contaminant with susceptible tissues. Lead intoxication can be observed in the wounded, in workers manufacturing munitions etc; moreover, lead has been documented to have a negative impact on the intellectual function of children at very low blood concentrations. It is concluded on the basis of the literature overview that replacement of lead by depleted uranium in munitions would be environmentally beneficial or largely insignificant because both lead and uranium are present in the environment.

Depleted uranium instead of lead in munitions: the lesser evil

International Nuclear Information System (INIS)

Jargin, Sergei V

2014-01-01

Uranium has many similarities to lead in its exposure mechanisms, metabolism and target organs. However, lead is more toxic, which is reflected in the threshold limit values. The main potential hazard associated with depleted uranium is inhalation of the aerosols created when a projectile hits an armoured target. A person can be exposed to lead in similar ways. Accidental dangerous exposures can result from contact with both substances. Encountering uranium fragments is of minor significance because of the low penetration depth of alpha particles emitted by uranium: they are unable to penetrate even the superficial keratin layer of human skin. An additional cancer risk attributable to the uranium exposure might be significant only in case of prolonged contact of the contaminant with susceptible tissues. Lead intoxication can be observed in the wounded, in workers manufacturing munitions etc; moreover, lead has been documented to have a negative impact on the intellectual function of children at very low blood concentrations. It is concluded on the basis of the literature overview that replacement of lead by depleted uranium in munitions would be environmentally beneficial or largely insignificant because both lead and uranium are present in the environment. (opinion)

Ultrastructural and metabolic changes in osteoblasts exposed to uranyl nitrate

International Nuclear Information System (INIS)

Tasat, D.R.; Orona, N.S.; Mandalunis, P.M.; Cabrini, R.L.; Ubios, A.M.

2007-01-01

Exposure to uranium is an occupational hazard to workers who continually handle uranium and an environmental risk to the population at large. Since the cellular and molecular pathways of uranium toxicity in osteoblast cells are still unknown, the aim of the present work was to evaluate the adverse effects of uranyl nitrate (UN) on osteoblasts both in vivo and in vitro. Herein we studied the osteoblastic ultrastructural changes induced by UN in vivo and analyzed cell proliferation, generation of reactive oxygen species (ROS), apoptosis, and alkaline phosphatase (APh) activity in osteoblasts exposed to various UN concentrations (0.1, 1, 10, and 100 μM) in vitro. Cell proliferation was quantified by means of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, ROS was determined using the nitro blue tetrazolium test, apoptosis was morphologically determined using Hoechst 3332 and APh activity was assayed spectrophotometrically. Electron microscopy revealed that the ultrastructure of active and inactive osteoblasts exposed to uranium presented cytoplasmic and nuclear alterations. In vitro, 1-100 μM UN failed to modify cell proliferation ratio and to induce apoptosis. ROS generation increased in a dose-dependent manner in all tested doses. APh activity was found to decrease in 1-100 μM UN-treated cells vs. controls. Our results show that UN modifies osteoblast cell metabolism by increasing ROS generation and reducing APh activity, suggesting that ROS may play a more complex role in cell physiology than simply causing oxidative damage. (orig.)

Uranium in the Near-shore Aquatic Food Chain: Studies on Periphyton and Asian Clams

International Nuclear Information System (INIS)

Bunn, Amoret L.; Miley, Terri B.; Eslinger, Paul W.; Brandt, Charles A.; Napier, Bruce A.

2007-01-01

The benthic aquatic organisms in the near-shore environment of the Columbia River are the first biological receptors that can be exposed to groundwater contaminants coming from the U.S. Department of Energy's Hanford Site. The primary contaminant of concern in the former nuclear fuels processing area at the Site, known as the 300 Area, is uranium. Currently, there are no national clean up criteria for uranium and ecological receptors. This report summarizes efforts to characterize biological uptake of uranium in the food chain of the benthic aquatic organisms and provide information to be used in future assessments of uranium and the ecosystem.

Total-Count Calibration Blocks for use in uranium Exploration

DEFF Research Database (Denmark)

Løvborg, Leif

Transportable calibration blocks for field scintillometers and borehole probes were manufactured from concrete and installed at calibration sites in Denmark and Greece. The concrete mixes were prepared from aggregates of quartz sand and crushed uranium-thorium ore. Hater-reducing agents and silica...... dust added to the cement paste produced concretes of acceptable porosity and pore structure. The content of ore was adjusted to provide block grades of approximately 2, 140, and 540 units of radioelement concentration (Ur). Thorium was estimated to contribute 0.39 ± 0.02 Ur per ppm Th. The adopted...

Global transcriptional analysis of short-term hepatic stress responses in Atlantic salmon (Salmo salar) exposed to depleted uranium

Science.gov (United States)

Song, You; Salbu, Brit; Teien, Hans-Christian; Heier, Lene Sørlie; Rosseland, Bjørn Olav; Høgåsen, Tore; Tollefsen, Knut Erik

2014-01-01

Potential environmental hazards of radionuclides are often studied at the individual level. Sufficient toxicogenomics data at the molecular/cellular level for understanding the effects and modes of toxic action (MoAs) of radionuclide is still lacking. The current article introduces transcriptomic data generated from a recent ecotoxicological study, with the aims to characterize the MoAs of a metallic radionuclide, deplete uranium (DU) in an ecologically and commercially important fish species, Atlantic salmon (Salmo salar). Salmon were exposed to three concentrations (0.25, 0.5 and 1.0 mg/L) of DU for 48 h. Short-term global transcriptional responses were studied using Agilent custom-designed high density 60,000-feature (60 k) salmonid oligonucleotide microarrays (oligoarray). The microarray datasets deposited at Gene Expression Omnibus (GEO ID: GSE58824) were associated with a recently published study by Song et al. (2014) in BMC Genomics. The authors describe the experimental data herein to build a platform for better understanding the toxic mechanisms and ecological hazard of radionuclides such as DU in fish. PMID:26484125

Global transcriptional analysis of short-term hepatic stress responses in Atlantic salmon (Salmo salar exposed to depleted uranium

Directory of Open Access Journals (Sweden)

You Song

2014-12-01

Full Text Available Potential environmental hazards of radionuclides are often studied at the individual level. Sufficient toxicogenomics data at the molecular/cellular level for understanding the effects and modes of toxic action (MoAs of radionuclide is still lacking. The current article introduces transcriptomic data generated from a recent ecotoxicological study, with the aims to characterize the MoAs of a metallic radionuclide, deplete uranium (DU in an ecologically and commercially important fish species, Atlantic salmon (Salmo salar. Salmon were exposed to three concentrations (0.25, 0.5 and 1.0 mg/L of DU for 48 h. Short-term global transcriptional responses were studied using Agilent custom-designed high density 60,000-feature (60 k salmonid oligonucleotide microarrays (oligoarray. The microarray datasets deposited at Gene Expression Omnibus (GEO ID: GSE58824 were associated with a recently published study by Song et al. (2014 in BMC Genomics. The authors describe the experimental data herein to build a platform for better understanding the toxic mechanisms and ecological hazard of radionuclides such as DU in fish.

Recovery of uranium in mine waters; Recuperation de l'uranium dans les eaux des mines

Energy Technology Data Exchange (ETDEWEB)

Sugier, P [Direction des Productions, CEA, Chatillon-Sur-Bagneux (France)

1967-06-15

In a brief introductory survey the author indicates the date on which leaching was first observed in the CEA mines and lists the main factors necessary for, or favourable to, the solubilization of uranium in mines. Information is given on the various sources of this type at present identified in France and the methods used to recover uranium in mines situated near ore-concentration plants. An explanation is given for the use of the calcium precipitation technique in connection with waters produced in mines not situated near ore-concentration plants. Data are given on the results of laboratory tests carried out on waters containing uranium, together with a description of an industrial-scale facility built in consequence of these tests. Details are given of the statistical results obtained. The author concludes by outlining the programme which will be implemented in the near future with a view to increasing the tonnage of uranium produced by in situ leaching and indicates that the CEA engineers are very optimistic about the prospects of this new low-cost method of producing uranium. (author) [French] Apres un bref rappel historique precisant la date de constatation du phenomene de lixiviation dans les mines d'uranium du Commissariat et un rapide inventaire des principales conditions necessaires ou favorisant la solubilisation de l'uranium dans les mines, auteur indique les differentes sources actuellement reconnues en France et les methodes utilisees pour recuperer l'uranium dans les mines situees pres d'une usine de concentration des minerais. Il donne ensuite les raisons motivant le choix du procede de precipitation calcique pour les eaux produites dans des mines eloignees des usines de concentration des minerais. Les resultats d'essais de laboratoire effectues sur des eaux chargees en uranium sont donnes et l'installation industrielle realisee a la suite de ces essais est decrite; les resultats statistiques obtenus sont detailles. En conclusion de son expose, l

Extraction of uranium from seawater: evaluation of uranium resources and plant siting

International Nuclear Information System (INIS)

Rodman, M.R.; Gordon, L.I.; Chen, A.C.T.

1979-02-01

This report deals with the evaluation of U.S. coastal waters as a uranium resource and with the selection of a suitable site for construction of a large-scale plant for uranium extraction. Evaluation of the resource revealed that although the concentration of uranium is quite low, about 3.3 ppB in seawater of average oceanic salinity, the amount present in the total volume of the oceans is very great, some 4.5 billion metric tons. Of this, perhaps only that uranium contained in the upper 100 meters or so of the surface well-mixed layer should be considered accessible for recovery, some 160 million tonnes. The study indicated that open ocean seawater acquired for the purpose of uranium extraction would be a more favorable resource than rivers entering the sea, cooling water of power plants, or the feed or effluent streams of existing plants producing other products such as magnesium, bromine, or potable and/or agricultural water from seawater. Various considerations led to the selection of a site for a pumped seawater coastal plant at a coastal location. Puerto Yabucoa, Puerto Rico was selected. Recommendations are given for further studies. 21 figures, 8 tables

Extraction of uranium from seawater: evaluation of uranium resources and plant siting

Energy Technology Data Exchange (ETDEWEB)

Rodman, M.R.; Gordon, L.I.; Chen, A.C.T.

1979-02-01

This report deals with the evaluation of U.S. coastal waters as a uranium resource and with the selection of a suitable site for construction of a large-scale plant for uranium extraction. Evaluation of the resource revealed that although the concentration of uranium is quite low, about 3.3 ppB in seawater of average oceanic salinity, the amount present in the total volume of the oceans is very great, some 4.5 billion metric tons. Of this, perhaps only that uranium contained in the upper 100 meters or so of the surface well-mixed layer should be considered accessible for recovery, some 160 million tonnes. The study indicated that open ocean seawater acquired for the purpose of uranium extraction would be a more favorable resource than rivers entering the sea, cooling water of power plants, or the feed or effluent streams of existing plants producing other products such as magnesium, bromine, or potable and/or agricultural water from seawater. Various considerations led to the selection of a site for a pumped seawater coastal plant at a coastal location. Puerto Yabucoa, Puerto Rico was selected. Recommendations are given for further studies. 21 figures, 8 tables.

Determination of radon and uranium in the groundwater of Bangalore city

International Nuclear Information System (INIS)

Somashekar, R.K.; Davis, Deljo; Jeban Singh, M.; Prakash, K.L.; Shivanna, K.

2010-01-01

Groundwater is a precious source of drinking water. Radon and uranium are the naturally occurring radioactive elements in water. The present study attempts to identify the nature of groundwater with respect to the radon and uranium in and around Bangalore city. The radon in groundwater is measured by the integrated instrumental field screening techniques using a radon in air monitor (RAD-7) with attached bubbler. The water after the radon measurement, analysed for the total uranium using ICP- AES. The Radon in water represented in Bq/L and total uranium in μg/L

Biomonitoring a human population inhabiting nearby a deactivated uranium mine

International Nuclear Information System (INIS)

Lourenço, J.; Pereira, R.; Pinto, F.; Caetano, T.; Silva, A.; Carvalheiro, T.

2013-01-01

Highlights: ► Human population environmentally exposed to uranium mining wastes. ► Significantly higher levels of manganese and uranium in peripheral blood samples. ► Significant DNA damages detected by the comet assay. ► Significant decrease of NK and T lymphocytes counts in exposed individuals. ► Concerns on the risks of human populations living nearby uranium mining areas. - Abstract: Environmental exposure to uranium and its daughter radionuclides, has been linked to several negative effects such as those related with important physiological processes, like hematopoiesis, and may also be associated with genotoxicity effects. Herein, genotoxic effects, immunotoxicity, trace elements and C reactive protein (CRP) analyses, were performed in peripheral blood samples collected from individuals of a population living near a deactivated uranium mine. C reactive protein analysis was performed to exclude candidates with active inflammatory processes from further evaluations. DNA damage and immunotoxicity (immunophenotyping and immune cell counts) were evaluated by comet assay and flow cytometry, respectively. Significant DNA damage was observed in the peripheral blood samples from volunteers living in the Cunha Baixa village. A significant decrease of NK and T lymphocytes counts were observed in the individuals from the Cunha Baixa village, when compared with individuals from the reference site. Uranium and manganese levels were significantly higher in the Cunha Baixa village inhabitants. On the other hand, zinc levels were significantly lower in those individuals when compared with the volunteers from the control village. Results suggest that inhabitants from Cunha Baixa have a higher risk of suffering from serious diseases such as cancer, since high DNA damages were observed in peripheral blood leukocytes and also decreased levels of NK and T cells, which play an essential role in the defense against tumor growth

Surficial uranium deposits in Algeria

International Nuclear Information System (INIS)

Mokaddem, M.; Fuchs, Y.

1984-01-01

Along southern border of the Hoggar (Algeria) Precambrian shield, Lower Palaeozoic sediments lie unconformably on weathered metamorphic rocks. Along the eastern border of the Tin Seririne basin some good examples of the weathered rocks underneath the unconformity are exposed. The palaeosurface is a peneplain with only minor topographical reliefs from one to a few metres high. The nature and intensity of the weathering process was controlled by the topography, and the existence of badly drained areas is particularly important. At one such area the Tahaggart uranium ore deposit was discovered. The uranium ore consists mainly of torbernite and autunite. The deposit is present in the weathered gneiss underneath the palaeosurface. Mineralogical and geochemical observations indicated that the ore deposit was formed during the period of weathering which was controlled by climatological and palaeotopographical factors. (author)

Distribution of natural uranium in groundwater around Kudankulam

International Nuclear Information System (INIS)

Selvi, B.S.; Vijayakumar, B.; Rana, B.K.; Ravi, P.M.

2016-01-01

A systematic study was carried out to estimate the uranium concentration in the ground water around Kudankulam in Southern Tamil Nadu. The uranium concentration in ground water varies from 0.2 to 6.6 μg/l, with a mean value of 2.0 μg/l. The Quantalase uranium analyzer was used to measure the uranium concentration. These groundwater samples were analyzed for the water quality parameters such as pH, conductance, total dissolved solids (TDS), salinity, chloride, and sulfate. An attempt has been made to correlate the uranium concentration with the water quality parameters. It is observed that conductance, TDS, salinity, chloride, and sulfate show positive correlation with uranium concentration. (author)

Uranium tailings reference materials

International Nuclear Information System (INIS)

Smith, C.W.; Steger, H.F.; Bowman, W.S.

1984-01-01

Samples of uranium tailings from Bancroft and Elliot Lake, Ontario, and from Beaverlodge and Rabbit Lake, Saskatchewan, have been prepared as compositional reference materials at the request of the National Uranium Tailings Research Program. The four samples, UTS-1 to UTS-4, were ground to minus 104 μm, each mixed in one lot and bottled in 200-g units for UTS-1 to UTS-3 and in 100-g units for UTS-4. The materials were tested for homogeneity with respect to uranium by neutron activation analysis and to iron by an acid-decomposition atomic absorption procedure. In a free choice analytical program, 18 laboratories contributed results for one or more of total iron, titanium, aluminum, calcium, barium, uranium, thorium, total sulphur, and sulphate for all four samples, and for nickel and arsenic in UTS-4 only. Based on a statistical analysis of the data, recommended values were assigned to all elements/constituents, except for sulphate in UTS-3 and nickel in UTS-4. The radioactivity of thorium-230, radium-226, lead-210, and polonium-210 in UTS-1 to UTS-4 and of thorium-232, radium-228, and thorium-228 in UTS-1 and UTS-2 was determined in a radioanalytical program composed of eight laboratories. Recommended values for the radioactivities and associated parameters were calculated by a statistical treatment of the results

Role of uranium speciation on its bioaccumulation, transfer and toxicity in plants. Application to phyto-remediation

International Nuclear Information System (INIS)

Laurette, J.

2011-01-01

Uranium is both a radiological and a chemical toxic, which naturally occurs in the environment as a trace element. Metal accumulation and distribution in plants is modulated by speciation. The aim of this PhD work was thus to assay uranium accumulation, intra planta repartition and toxicity according to its speciation in solution. Acquired knowledge will be applied in phyto-remediation technologies. We exposed three plant species (sunflower, oilseed rape and wheat) to a panel of hydroponic media containing one or two predominant uranium chemical forms. After exposition in these various contaminated media, we evaluated uranium content in plant organs by ICP-MS. In order to investigate uranium repartition and localization at organ/tissue and cellular scales, we carried out four complementary imaging techniques. The uranium repartition within soluble and membrane fractions in roots and shoot was assayed after fractionation and separation through a chromatography column. In parallel, we used X-ray absorption spectroscopy to determine the molecular-level structure of chemical species formed by uranium in exposure media and plant samples. Finally, we explored toxic effects of uranium on plant growth and metabolism. Our results revealed three schema of accumulation according to the uranium speciation in the exposure medium: when exposed to UO 2 2+ free ion, root accumulation is high, but uranium transfer to the shoots is limited. Uranium is immobilized by adsorption on root surface and precipitation on root cell walls, associated with phosphorus and calcium. The existence of uranium-binding proteins is also suggested. When complexed with phosphate, root accumulation is considerably reduced and translocation becomes negligible. Uranium is precipitated as described above. Conversely, complexation with carbonate or citrate reduces root accumulation but drastically increases translocation to the shoots. If some uranyl phosphate precipitates are still found in root and shoot

Uranium extraction from gold-uranium ores

Energy Technology Data Exchange (ETDEWEB)

Laskorin, B.N.; Golynko, Z.Sh.

1981-01-01

The process of uranium extraction from gold-uranium ores in the South Africa is considered. Flowsheets of reprocessing gold-uranium conglomerates, pile processing and uranium extraction from the ores are presented. Continuous counter flow ion-exchange process of uranium extraction using strong-active or weak-active resins is noted to be the most perspective and economical one. The ion-exchange uranium separation with the succeeding extraction is also the perspective one.

Comparative study of uranium concentration in water samples of SW and NE Punjab, India

International Nuclear Information System (INIS)

Saini, Komal; Bajwa, B.S.

2014-01-01

Since the commencement of the earth, radiations and natural radioactivity has always been a part of environment. Uranium is heaviest naturally occurring element which is widespread in nature, mainly occurs in granites mineral deposits. The natural weathering of rocks such as granite dissolves the natural uranium, which goes into groundwater by leaching and precipitation called illumination process. People are always exposed to certain amount of uranium from air, water, soil and food as it is usually present in these components. About 85% of ingested uranium enter into human body through drinking water which makes it very important to estimate uranium concentration in potable water. Uranium and some other heavy metals may increase the risk of kidney damage, cancer diseases where experimental evidence suggests that respiratory and reproductive system are also affected by uranium exposure. In the present study comparative study of uranium concentration in potable water samples of SW and NE Punjab has been analysed

Experimental evaluation of the detection threshold of uranium in urine samples

International Nuclear Information System (INIS)

Ferreyra, M. D.; Suarez Mendez, Sebastian; Tossi, Mirta H.

1999-01-01

The routine internal dosimetric tests for nuclear installations workers includes the determination of uranium in urine. The analysis is carried out, after chemical treatment, by UV fluorometry, comparing the results with urine blank samples from workers not exposed professionally to contamination. The fluctuation of the results of the uranium content in the blank samples greatly affects the determinations. In 30 blank samples the uranium content was determined and the results were evaluated by three calculation methods: 1) The procedure recommended by IUPAC; 2) The graphical method; 3) and The error propagation method. The last one has been adopted for the calculation of the detection threshold. (authors)

Risk due assessment of the intake of uranium isotopes in mineral spring waters

International Nuclear Information System (INIS)

Camargo, Iara M.C.; Mazzilli, Barbara

1998-01-01

To complement the data of a previous research concerning the evaluation of the lifetime risk of radiation-induced cancer due to the injection of 226 Ra, 228 Ra and 222 Rn in mineral spring waters from a natural highly radioactive region of Brazil. The study was performed to evaluate the lifetime risk of radiation-induced cancer due to the ingestion of 238 U and 234 U in the same spring waters. It is assumed that the risk coefficient for natural U isotopes is the same as for the 226 Ra-induced bone sarcomas and that the equilibrium for skeletal content is 25 times the daily ingestion of 226 Ra, but 11 times the daily ingestion of long-lived uranium isotopes. Waters samples were collected seasonally over a period of one year at all the spring sites used by the local population of Aguas da Prata, Sao Paulo State, Brazil. Concentrations ranging from 2.0 to 28.4 mBq/L and from 4.7 to 143 mBq/L were observed for 238 U and 234 U, respectively. Based upon the measured concentrations the lifetime risk due to the ingestion of uranium isotopes was estimated. A total of 0.3 uranium-induced cancers for 10 6 exposed persons was predicted, suggesting that chronic ingestion of uranium at the levels observed at these springs will result in an incremental increase of fatal cancers of 0.1%. (author)

Trends in uranium supply

Energy Technology Data Exchange (ETDEWEB)

Hansen, M [International Atomic Energy Agency, Division of Nuclear Power and Reactors, Nuclear Materials and Fuel Cycle Section, Vienna (Austria)

1976-07-01

Prior to the development of nuclear power, uranium ores were used to a very limited extent as a ceramic colouring agent, as a source of radium and in some places as a source of vanadium. Perhaps before that, because of the bright orange and yellow colours of its secondary ores, it was probably used as ceremonial paint by primitive man. After the discovery of nuclear fission a whole new industry emerged, complete with its problems of demand, resources and supply. Spurred by special incentives in the early years of this new nuclear industry, prospectors discovered over 20 000 occurrences of uranium in North America alone, and by 1959 total world production reached a peak of 34 000 tonnes uranium from mines in South Africa, Canada and United States. This rapid growth also led to new problems. As purchases for military purposes ended, government procurement contracts were not renewed, and the large reserves developed as a result of government purchase incentives, in combination with lack of substantial commercial market, resulted in an over-supply of uranium. Typically, an over-supply of uranium together with national stockpiling at low prices resulted in depression of prices to less than $5 per pound by 1971. Although forecasts made in the early 1970's increased confidence in the future of nuclear power, and consequently the demand for uranium, prices remained low until the end of 1973 when OPEC announced a very large increase in oil prices and quite naturally, prices for coal also rose substantially. The economics of nuclear fuel immediately improved and prices for uranium began to climb in 1974. But the world-wide impact of the OPEC decision also produced negative effects on the uranium industry. Uranium production costs rose dramatically, as did capital costs, and money for investment in new uranium ventures became more scarce and more expensive. However, the uranium supply picture today offers hope of satisfactory development in spite of the many problems to be

Trends in uranium supply

International Nuclear Information System (INIS)

Hansen, M.

1976-01-01

Prior to the development of nuclear power, uranium ores were used to a very limited extent as a ceramic colouring agent, as a source of radium and in some places as a source of vanadium. Perhaps before that, because of the bright orange and yellow colours of its secondary ores, it was probably used as ceremonial paint by primitive man. After the discovery of nuclear fission a whole new industry emerged, complete with its problems of demand, resources and supply. Spurred by special incentives in the early years of this new nuclear industry, prospectors discovered over 20 000 occurrences of uranium in North America alone, and by 1959 total world production reached a peak of 34 000 tonnes uranium from mines in South Africa, Canada and United States. This rapid growth also led to new problems. As purchases for military purposes ended, government procurement contracts were not renewed, and the large reserves developed as a result of government purchase incentives, in combination with lack of substantial commercial market, resulted in an over-supply of uranium. Typically, an over-supply of uranium together with national stockpiling at low prices resulted in depression of prices to less than $5 per pound by 1971. Although forecasts made in the early 1970's increased confidence in the future of nuclear power, and consequently the demand for uranium, prices remained low until the end of 1973 when OPEC announced a very large increase in oil prices and quite naturally, prices for coal also rose substantially. The economics of nuclear fuel immediately improved and prices for uranium began to climb in 1974. But the world-wide impact of the OPEC decision also produced negative effects on the uranium industry. Uranium production costs rose dramatically, as did capital costs, and money for investment in new uranium ventures became more scarce and more expensive. However, the uranium supply picture today offers hope of satisfactory development in spite of the many problems to be

Method for converting uranium oxides to uranium metal

International Nuclear Information System (INIS)

Duerksen, W.K.

1988-01-01

A method for converting uranium oxide to uranium metal is described comprising the steps of heating uranium oxide in the presence of a reducing agent to a temperature sufficient to reduce the uranium oxide to uranium metal and form a heterogeneous mixture of a uranium metal product and oxide by-products, heating the mixture in a hydrogen atmosphere at a temperature sufficient to convert uranium metal in the mixture to uranium hydride, cooling the resulting uranium hydride-containing mixture to a temperature sufficient to produce a ferromagnetic transition in the uranium hydride, magnetically separating the cooled uranium hydride from the mixture, and thereafter heating the separated uranium hydride in an inert atmosphere to a temperature sufficient to convert the uranium hydride to uranium metal

New development stage of China's uranium industry

International Nuclear Information System (INIS)

Zhang Rong

2001-01-01

From the early 1980s China adjusted its uranium industry to better meet the market economy requirements. Until 1997, the adjustment has been completed. The technical and managerial improvements result in a more efficient uranium production. In 1996 a series of events related to the nuclear power development of China manifests very favorable situation for the uranium industry. The first two nuclear power plants with a total installed capacity of 2100 MW in the mainland of China have been operating safely and steadily for several years. The additional nuclear power projects to be constructed for the rest of this century are implemented in an all-round way. Four plants with eight reactors of a total of 6900 MW have entered their construction period in succession. In 1996 a commercial ISL mine in Xinjiang with annual capacity 100 tU was completed, and the larger scale of ISL mine is expected to be constructed by 2000. The Benxi uranium mine in northeast China was put into production. It applies some new mining and processing technologies and improved management, which might serve as a new model of uranium mines in China. (author)

Immobilization of uranium in biofilm microorganisms exposed to groundwater seeps over granitic rock tunnel walls in Olkiluoto, Finland

Science.gov (United States)

Krawczyk-Bärsch, Evelyn; Lünsdorf, Heinrich; Pedersen, Karsten; Arnold, Thuro; Bok, Frank; Steudtner, Robin; Lehtinen, Anne; Brendler, Vinzenz

2012-11-01

In an underground rock characterization facility, the ONKALO tunnel in Finland, massive 5-10-mm thick biofilms were observed attached to tunnel walls where groundwater was seeping from bedrock fractures at a depth of 70 m. In laboratory experiments performed in a flow cell with detached biofilms to study the effect of uranium on the biofilm, uranium was added to the circulating groundwater (CGW) obtained from the fracture feeding the biofilm. The final uranium concentration in the CGW was adjusted to 4.25 × 10-5 M, in the range expected from a leaking spent nuclear fuel (SNF) canister in a future underground repository. The effects were investigated using microelectrodes to measure pH and Eh, time-resolved laser fluorescence spectroscopy (TRLFS), energy-filtered transmission electron microscopy (EF-TEM), and electron energy-loss spectroscopy (EELS) studies and thermodynamic calculations were utilized as well. The results indicated that the studied biofilms constituted their own microenvironments, which differed significantly from that of the CGW. A pH of 5.37 was recorded inside the biofilm, approximately 3.5 units lower than the pH observed in the CGW, due to sulfide oxidation to sulfuric acid in the biofilm. Similarly, the Eh of +73 mV inside the biofilm was approximately 420 mV lower than the Eh measured in the CGW. Adding uranium increased the pH in the biofilm to 7.27 and reduced the Eh to -164 mV. The changes of Eh and pH influenced the bioavailability of uranium, since microbial metabolic processes are sensitive to metals and their speciation. EF-TEM investigations indicated that uranium in the biofilm was immobilized intracellularly in microorganisms by the formation of metabolically mediated uranyl phosphate, similar to needle-shaped autunite (Ca[UO2]2[PO4]2·2-6H2O) or meta-autunite (Ca[UO2]2[PO4]2·10-12H2O). In contrast, TRLFS studies of the contaminated CGW identified aqueous uranium carbonate species, likely (Ca2UO2[CO3]3), formed due to the high

Trans-generational study of DNA alterations and their consequences on life history traits and energy budget of Daphnia magna exposed to depleted uranium

International Nuclear Information System (INIS)

Plaire, Delphine

2013-01-01

Understanding how toxicants affect species at various levels of biological organization is a major research goal in both ecotoxicology and radioecology. As part of IRSN program ENVIRHOM, which aims to assess environmental risks related to the presence of radionuclides in the environment, this PhD work explored how depleted uranium alters DNA and affects life history traits (survival, growth and reproduction) of an aquatic invertebrate, Daphnia magna. To answer to this problematic, an experimental approach and a modeling approach are conducted. An experimental study is performed to evaluate DNA accumulation and transmission during an uranium exposure (0; 2; 9.9; 22.2 and 50 μg.L -1 ) over two successive generations (F0 and F1). Different exposures scenarios (continuous, post-hatching and embryo exposure) are achieved to test the specific sensitivity of several life stages to uranium. Genotoxic effects are estimated using random amplified DNA technique combined with PCR (PCR-RAPD). In continuous and post-hatching exposure scenarios, results highlighted an accumulation and a transmission of DNA damage across generations with an increase in effect severity. DNA alterations are reported at hatching of the F1 generation at a concentration as low as 2 μg.L -1 . Effects on growth and reproduction are stronger when the embryo stage is exposed and remain visible at 9.9 μg.L -1 despite a return in a clean medium at hatching. Results suggest that DNA damage could be used as early indicators of future effects on life history traits. A mechanistic analysis of experimental results is conducted using a DEBtox model (dynamic energy budget applied to toxicology) to better understand the causes of the increase in effect severity across generations. A model with two stress factors (one correlated to external concentration and another correlated to a damage level) is developed. Results of fits suggest the involvement of one second mode of action to explain immediate effects of

Determination of total uranium by mass spectrometry utilizing the isotopic dilution technique

International Nuclear Information System (INIS)

Cretella, R.F.; Noutary, C.J.; Servant, R.E.

1981-01-01

The isotopic dilution associated to mass spectrometry is a high-sensitivity technique that allows to work with microquantities of the sample, making it possible to analize the content in highly radioactive solutions with excellent accuracy and minimum risk. The proposed technique is described and its results are discussed through the analysis of: 1) A synthetic sample that simulates dissolved spent fuel elements; 2) Uranium dioxide of nuclear purity and 3) Uranium concentrate. 233 U(ORNL) was employed as a tracer and a Nuclide 12-90-SU mass spectrometer of simple magnetic focus as measurement instrument. The accuracy reached in the analyses is better than 0.5% with a reliability of 95%. The analysis of the errors shows that their main contributing source are the errors in the measurement of the isotopic ratios. (M.E.L.) [es

Uranium from German nuclear power projects of the 1940s - a nuclear forensic investigation

International Nuclear Information System (INIS)

Mayer, Klaus; Wallenius, Maria; Luetzenkirchen, Klaus; Horta, Joan; Nicholl, Adrian; Rasmussen, Gert; Belle, Pieter van; Varga, Zsolt; Buda, Razvan; Erdmann, Nicole; Kratz, Jens-Volker; Trautmann, Norbert; Fifield, L. Keith; Tims, Stephen G.; Froehlich, Michaela B.; Steier, Peter

2015-01-01

Here we present a nuclear forensic study of uranium from German nuclear projects which used different geometries of metallic uranium fuel. Through measurement of the 230 Th/ 234 U ratio, we could determine that the material had been produced in the period from 1940 to 1943. To determine the geographical origin of the uranium, the rare-earth-element content and the 87 Sr/ 86 Sr ratio were measured. The results provide evidence that the uranium was mined in the Czech Republic. Trace amounts of 236 U and 239 Pu were detected at the level of their natural abundance, which indicates that the uranium fuel was not exposed to any major neutron fluence. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Uranium in the Near-shore Aquatic Food Chain: Studies on Periphyton and Asian Clams

Energy Technology Data Exchange (ETDEWEB)

Bunn, Amoret L.; Miley, Terri B.; Eslinger, Paul W.; Brandt, Charles A.; Napier, Bruce A.

2007-12-31

The benthic aquatic organisms in the near-shore environment of the Columbia River are the first biological receptors that can be exposed to groundwater contaminants coming from the U.S. Department of Energy's Hanford Site. The primary contaminant of concern in the former nuclear fuels processing area at the Site, known as the 300 Area, is uranium. Currently, there are no national clean up criteria for uranium and ecological receptors. This report summarizes efforts to characterize biological uptake of uranium in the food chain of the benthic aquatic organisms and provide information to be used in future assessments of uranium and the ecosystem.

Uranium induces oxidative stress in lung epithelial cells

International Nuclear Information System (INIS)

Periyakaruppan, Adaikkappan; Kumar, Felix; Sarkar, Shubhashish; Sharma, Chidananda S.; Ramesh, Govindarajan T.

2007-01-01

Uranium compounds are widely used in the nuclear fuel cycle, antitank weapons, tank armor, and also as a pigment to color ceramics and glass. Effective management of waste uranium compounds is necessary to prevent exposure to avoid adverse health effects on the population. Health risks associated with uranium exposure includes kidney disease and respiratory disorders. In addition, several published results have shown uranium or depleted uranium causes DNA damage, mutagenicity, cancer and neurological defects. In the current study, uranium toxicity was evaluated in rat lung epithelial cells. The study shows uranium induces significant oxidative stress in rat lung epithelial cells followed by concomitant decrease in the antioxidant potential of the cells. Treatment with uranium to rat lung epithelial cells also decreased cell proliferation after 72 h in culture. The decrease in cell proliferation was attributed to loss of total glutathione and superoxide dismutase in the presence of uranium. Thus the results indicate the ineffectiveness of antioxidant system's response to the oxidative stress induced by uranium in the cells. (orig.)

Life-cycle effects of sediment-associated uranium on Chironomus riparius (diptera: chironomidae)

Energy Technology Data Exchange (ETDEWEB)

Dias, V.; Ksas, B.; Camilleri, V.; Bonzom, J.M. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

2004-07-01

In aquatic ecosystems, sediments function as reservoir for many of the more persistent chemicals that are introduced into surface waters. Sediments provide a habitat for various benthic macro-invertebrates, which are exposed to sediment-associated chemicals both directly and via food intake. These chemicals may be directly toxic to benthic macro-invertebrates and can be integrated into food chain. Benthic macro-invertebrates play an important role in the ecosystem structure and functioning. In particular, they represent an important component of aquatic food chains. Among the non biologically essential metals, data concerning uranium fate and effects on freshwater benthic invertebrates are sparse. The present study aimed to estimate effects of a chronic uranium exposure on life-cycle traits of Chironomus riparius. To achieve this goal, (i) first instar larvae were exposed to a series of concentrations of uranium via the sediment, and (ii) a number of developmental (e.g. growth) and reproductive (e.g. emergence, fecundity, viability) endpoints, through parental and into F1 generations, were evaluated. Within the framework of ecological risk assessment, these data will help the derivation of a sediment guideline value for uranium that does not currently exist in France or elsewhere due to a lack of toxicity data. (author)

Life-cycle effects of sediment-associated uranium on Chironomus riparius (diptera: chironomidae)

International Nuclear Information System (INIS)

Dias, V.; Ksas, B.; Camilleri, V.; Bonzom, J.M.

2004-01-01

In aquatic ecosystems, sediments function as reservoir for many of the more persistent chemicals that are introduced into surface waters. Sediments provide a habitat for various benthic macro-invertebrates, which are exposed to sediment-associated chemicals both directly and via food intake. These chemicals may be directly toxic to benthic macro-invertebrates and can be integrated into food chain. Benthic macro-invertebrates play an important role in the ecosystem structure and functioning. In particular, they represent an important component of aquatic food chains. Among the non biologically essential metals, data concerning uranium fate and effects on freshwater benthic invertebrates are sparse. The present study aimed to estimate effects of a chronic uranium exposure on life-cycle traits of Chironomus riparius. To achieve this goal, (i) first instar larvae were exposed to a series of concentrations of uranium via the sediment, and (ii) a number of developmental (e.g. growth) and reproductive (e.g. emergence, fecundity, viability) endpoints, through parental and into F1 generations, were evaluated. Within the framework of ecological risk assessment, these data will help the derivation of a sediment guideline value for uranium that does not currently exist in France or elsewhere due to a lack of toxicity data. (author)

On the distribution of uranium in hair: Non-destructive analysis using synchrotron radiation induced X-ray fluorescence microprobe techniques

Science.gov (United States)

Israelsson, A.; Eriksson, M.; Pettersson, H. B. L.

2015-06-01

In the present study the distribution of uranium in single human hair shafts has been evaluated using two synchrotron radiation (SR) based micro X-ray fluorescence techniques; SR μ-XRF and confocal SR μ-XRF. The hair shafts originated from persons that have been exposed to elevated uranium concentrations. Two different groups have been studied, i) workers at a nuclear fuel fabrication factory, exposed mainly by inhalation and ii) owners of drilled bedrock wells exposed by ingestion of water. The measurements were carried out on the FLUO beamline at the synchrotron radiation facility ANKA, Karlsruhe. The experiment was optimized to detect U with a beam size of 6.8 μm × 3 μm beam focus allowing detection down to ppb levels of U in 10 s (SR μ-XRF setup) and 70 s (SR confocal μ-XRF setup) measurements. It was found that the uranium was present in a 10-15 μm peripheral layer of the hair shafts for both groups studied. Furthermore, potential external hair contamination was studied by scanning of unwashed hair shafts from the workers. Sites of very high uranium signal were identified as particles containing uranium. Such particles, were also seen in complementary analyses using variable pressure electron microscope coupled with energy dispersive X-ray analyzer (ESEM-EDX). However, the particles were not visible in washed hair shafts. These findings can further increase the understanding of uranium excretion in hair and its potential use as a biomonitor.

Method for converting uranium oxides to uranium metal

Science.gov (United States)

Duerksen, Walter K.

1988-01-01

A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

Extraction of uranium low-grade ores from Great Divide Basin, Wyoming. National Uranium Resource Evaluation

International Nuclear Information System (INIS)

Judd, J.C.; Nichols, I.L.; Huiatt, J.L.

1983-04-01

The US Bureau of Mines is investigating the leachability of carbonaceous uranium ore samples submitted by the DOE under an Interagency Agreement. Studies on eight samples from the Great Divide Basin, Wyoming, are the basis of this report. The uranium content of the eight ore samples ranged from 0.003 to 0.03% U 3 O 8 and contained 0.7 to 45% organic carbon. Experiments were performed to determine the feasibility of extracting uranium using acid leaching, roast-acid leaching and pressure leaching techniques. Acid leaching with 600 lb/ton H 2 SO 4 plus 10 lb/ton NaClO 3 for 18 h at 70 0 C extracted 65 to 83% of the uranium. One sample responded best to a roast-leach treatment. When roasting for 4 h at 500 0 C followed by acid leaching of the calcine using 600 lb/ton H 2 SO 4 , the uranium extraction was 82%. Two of the samples responded best to an oxidative pressure leach for 3 h at 200 0 C under a total pressure of 260 psig; uranium extractions were 78 and 82%

Uranium Sequestration by Aluminum Phosphate Minerals in Unsaturated Soils

International Nuclear Information System (INIS)

Jerden, James L. Jr.

2007-01-01

A mineralogical and geochemical study of soils developed from the unmined Coles Hill uranium deposit (Virginia) was undertaken to determine how phosphorous influences the speciation of uranium in an oxidizing soil/saprolite system typical of the eastern United States. This paper presents mineralogical and geochemical results that identify and quantify the processes by which uranium has been sequestered in these soils. It was found that uranium is not leached from the saturated soil zone (saprolites) overlying the deposit due to the formation of a sparingly soluble uranyl phosphate mineral of the meta-autunite group. The concentration of uranium in the saprolites is approximately 1000 mg uranium per kg of saprolite. It was also found that a significant amount of uranium was retained in the unsaturated soil zone overlying uranium-rich saprolites. The uranium concentration in the unsaturated soils is approximately 200 mg uranium per kg of soil (20 times higher than uranium concentrations in similar soils adjacent to the deposit). Mineralogical evidence indicates that uranium in this zone is sequestered by a barium-strontium-calcium aluminum phosphate mineral of the crandallite group (gorceixite). This mineral is intimately inter-grown with iron and manganese oxides that also contain uranium. The amount of uranium associated with both the aluminum phosphates (as much as 1.4 weight percent) has been measured by electron microprobe micro-analyses and the geochemical conditions under which these minerals formed has been studied using thermodynamic reaction path modeling. The geochemical data and modeling results suggest the meta-autunite group minerals present in the saprolites overlying the deposit are unstable in the unsaturated zone soils overlying the deposit due to a decrease in soil pH (down to a pH of 4.5) at depths less than 5 meters below the surface. Mineralogical observations suggest that, once exposed to the unsaturated environment, the meta-autunite group

Natural uranium toxicology - evaluation of internal contamination in man

International Nuclear Information System (INIS)

Chalabreysse, J.

1968-01-01

After reminding the physical and chemical properties of natural uranium which might affect its toxicology, a comprehensive investigation upon natural uranium metabolism and toxicity and after applying occupational exposure standards to this particular poison, it has been determined, from accident reports and human experience reported in the related literature, a series of formulae obtained by theoretical mathematical development giving principles for internal contamination monitoring and disclosure by determining uranium in the urine of occupationally exposed individuals. An assay is performed to determine individual internal contamination according to the various contamination cases. The outlined purposes, mainly practical, required some options and extrapolations. The proposed formula allows a preliminary approach and also to determine shortly a contamination extent or to discuss the systematical urinalysis results as compared with individual radio-toxicology monitoring professional standards. (author) [fr

Uranium 1999. Resources, production and demand

International Nuclear Information System (INIS)

2000-01-01

In recent years, the world uranium market has been characterised by an imbalance between demand and supply and persistently depressed uranium prices. World uranium production currently satisfies between 55 and 60 per cent of the total reactor-related requirements, while the rest of the demand is met by secondary sources including the conversion of excess defence material and stockpiles, primarily from Eastern Europe. Although the future availability of these secondary sources remains unclear, projected low-cost production capability is expected to satisfy a considerable part of demand through to 2015. Information in this report provides insights into changes expected in uranium supply and demand over the next 15 years. The 'Red Book', jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, is the foremost world reference on uranium. It is based on official information from 49 countries and includes compilations of statistics on resources, exploration, production and demand as of 1 January 1999. It provides substantial new information from all of the major uranium producing centres in Africa, Australia, Eastern Europe, North America and the New Independent States. It also contains an international expert analysis of industry statistics and world-wide projections of nuclear energy growth, uranium requirements and uranium supply. (authors)

The delayed neutron method of uranium analysis

International Nuclear Information System (INIS)

Wall, T.

1989-01-01

The technique of delayed neutron analysis (DNA) is discussed. The DNA rig installed on the MOATA reactor, the assay standards and the types of samples which have been assayed are described. Of the total sample throughput of about 55,000 units since the uranium analysis service began, some 78% has been concerned with analysis of uranium ore samples derived from mining and exploration. Delayed neutron analysis provides a high sensitivity, low cost uranium analysis method for both uranium exploration and other applications. It is particularly suitable for analysis of large batch samples and for non-destructive analysis over a wide range of matrices. 8 refs., 4 figs., 3 tabs

Status of technology of uranium recovery from seawater

International Nuclear Information System (INIS)

Sugo, Takanobu; Saito, Kyoichi.

1990-01-01

By bringing the solid material called adsorbent in contact with seawater, uranium can be collected, therefore, the adsorbent to which uranium was adsorbed in seawater can be regarded as the resource of uranium storing. To the adsorbent, also rare metals are concentrated in addition to uranium. From such viewpoint, the development of the technology for collecting seawater uranium is important for the Japanese energy policy. The uranium concentration in seawater is about 3 mg/m 3 and its form of dissolution is uranyl tricarbonate ions. The technology of collecting seawater uranium is the separation technology for extracting the component of very low concentration from the aqueous solution containing many components. The total amount of uranium in the whole oceans reaches about 4 billion t, which is about 1000 times as much as the uranium commercially mined on land. It is the target of the technology to make artificial uranium ore of as high quality as possible quickly. The process of collecting seawater uranium comprises adsorption, desorption, separation and enrichment. As the adsorbents, hydrated titanium oxide and chelate resin represented by amidoxime are promising. The adsorption system is described. (K.I.)

Geology and exploration of the Rum Jungle Uranium Field

International Nuclear Information System (INIS)

Fraser, W.J.

1980-01-01

The Rum Jungle Uranium Field was discovered by a private prospector in 1949. A total of 3530 tonnes of uranium oxide was mined and treated from four ore-bodies by Territory Enterprises Pty. Limited who managed the Rum Jungle Project on behalf of the Australian Atomic Energy Commission until the closure of operations in 1971. One small low grade uranium orebody remains to be developed. Lead, zinc, copper, cobalt and nickel were found zoned sub vertically with uranium at one deposit. One medium sized lead, zinc, copper, cobalt and nickel deposit remains to be developed and one small copper deposit with minor uranium was mined. The basemetal deposits show a regional zoning relationship with the known uranium mineralization. Uranium and basemetal mineralization is hosted by graphitic or chloritic, pyritic shales at the contact with a magnesite. These rocks are in the lower part of a sequence of Lower Proterozoic sediments which unconformably overlie Archaean basement complexes. The sediments and complexes are displaced by Giants Reef Fault and sub-parallel shears and linears may further control mineralization. Nearly 50km of the prospective shale/magnesite contact was tested by total count radiometric surveys, various electrical methods, auger, rotary percussion and diamond drilling. The source for the uranium mineralization was probably the Archaean basement complexes from which uranium was initially deposited as protore by either chemical precipitation or clay adsorption in the shale units or as detrital placers in quartz pebble conglomerates immediately overlying the basement complexes. (author)

Status and development of uranium prospection methods

International Nuclear Information System (INIS)

Barthel, F.

1978-01-01

In radiometric prospection, gamma measuring equipment is widely used. Simple instruments, so-called scintillometers, can only measure total radiation while spectrometers permit separate measurements of uranium, thorium, or calcium via daughter products of their decay chains. Depending on the target investigated, airborne, carborne, or footborne methods are employed. In radon prospection the gaseous decay product radon is measured as a sign of hidden uranium enrichment in ground air or water from springs. Due to its high solubility, uranium is well suited for geochemical prospection where uranium concentrations in bodies of water, river sediments, soil and rock types are determined. There is a trend in uranium prospection towards the discovery of hidden orifications. Novel techniques, e.g. airborne geochemistry, isotope chemistry, tracer element measurement, etc. are being tested with a view to their suitability for uranium prospection. (orig./HP) 891 HP/orig.- 892 MKO [de

Uranium

International Nuclear Information System (INIS)

Cuney, M.; Pagel, M.; Leroy, J.

1992-01-01

First, this book presents the physico-chemical properties of Uranium and the consequences which can be deduced from the study of numerous geological process. The authors describe natural distribution of Uranium at different scales and on different supports, and main Uranium minerals. A great place in the book is assigned to description and classification of uranium deposits. The book gives also notions on prospection and exploitation of uranium deposits. Historical aspects of Uranium economical development (Uranium resources, production, supply and demand, operating costs) are given in the last chapter. 7 refs., 17 figs

Environmental impact of uranium mining and milling: an American view

International Nuclear Information System (INIS)

Momeni, M.H.

1981-01-01

The radiation dose rates to man from uranium milling activities are discussed. The sources of radiation, the radioisotopes involved, and the environmental exposure pathways are described. Risks of cancer to exposed individuals are presented and recommendations made for mitigation of contamination

Effect of vitamin E and C supplementation on oxidative damage and total antioxidant capacity in lead-exposed workers.

Science.gov (United States)

Rendón-Ramírez, Adela-Leonor; Maldonado-Vega, María; Quintanar-Escorza, Martha-Angelica; Hernández, Gerardo; Arévalo-Rivas, Bertha-Isabel; Zentella-Dehesa, Alejandro; Calderón-Salinas, José-Víctor

2014-01-01

The molecular response of the antioxidant system and the effects of antioxidant supplementation against oxidative insult in lead-exposed workers has not been sufficiently studied. In this work, antioxidants (vitamin E 400 IU+vitamin C 1g/daily) were supplemented for one year to 15 workers exposed to lead (73 μg of lead/dl of blood) and the results were compared with those on 19 non-lead exposed workers (6.7 μg of lead/dl). Lead intoxication was accompanied by a high oxidative damage and an increment in the erythrocyte antioxidant response due to increased activity of catalase and superoxide dismutase. Antioxidant supplementations decreased significantly the oxidative damage as well as the total antioxidant capacity induced by lead intoxication with reduction of the antioxidant enzyme activities. We conclude that antioxidant supplementation is effective in reducing oxidative damage and induces modifications in the physiopathological status of the antioxidant response in lead-exposed workers. Copyright © 2013 Elsevier B.V. All rights reserved.

Uranium

International Nuclear Information System (INIS)

Poty, B.; Cuney, M.; Bruneton, P.; Virlogeux, D.; Capus, G.

2010-01-01

With the worldwide revival of nuclear energy comes the question of uranium reserves. For more than 20 years, nuclear energy has been neglected and uranium prospecting has been practically abandoned. Therefore, present day production covers only 70% of needs and stocks are decreasing. Production is to double by 2030 which represents a huge industrial challenge. The FBR-type reactors technology, which allows to consume the whole uranium content of the fuel, is developing in several countries and will ensure the long-term development of nuclear fission. However, the implementation of these reactors (the generation 4) will be progressive during the second half of the 21. century. For this reason an active search for uranium ores will be necessary during the whole 21. century to ensure the fueling of light water reactors which are huge uranium consumers. This dossier covers all the aspects of natural uranium production: mineralogy, geochemistry, types of deposits, world distribution of deposits with a particular attention given to French deposits, the exploitation of which is abandoned today. Finally, exploitation, ore processing and the economical aspects are presented. Contents: 1 - the uranium element and its minerals: from uranium discovery to its industrial utilization, the main uranium minerals (minerals with tetravalent uranium, minerals with hexavalent uranium); 2 - uranium in the Earth's crust and its geochemical properties: distribution (in sedimentary rocks, in magmatic rocks, in metamorphic rocks, in soils and vegetation), geochemistry (uranium solubility and valence in magmas, uranium speciation in aqueous solution, solubility of the main uranium minerals in aqueous solution, uranium mobilization and precipitation); 3 - geology of the main types of uranium deposits: economical criteria for a deposit, structural diversity of deposits, classification, world distribution of deposits, distribution of deposits with time, superficial deposits, uranium

International uranium production. A South African perspective

International Nuclear Information System (INIS)

Sinclair-Smith, D.

1984-01-01

Between 1981 and 1983 South Africa experienced a decline in its uranium resources of 23% in the less than $80/kg U category and 12% in the less than $130/kg U category. In 1983 only $5 million was spent on exploration, with activities being concentrated in the Witwatersrand Basin as a byproduct of gold exploration. South Africa has maintained a production level of around 6000 mt U in 1981, 1982 and 1983. One unusual feature of the South African uranium scene is the ability to selectively dump relatively high grade uranium tailings after the extraction of gold and to rework this material as well as material dumped prior to the emergence of the uranium industry. Uranium from this source amounted to some 28% of total production in 1983. (L.L.) (2 tabs., 6 figs.)

Contamination by depleted uranium (Du) in South Serbia

International Nuclear Information System (INIS)

Popovic, L.; Todorovic, J.; Bozic, P.; Stevanovic, Z.

2006-01-01

The paper present the results of the study on D.U. (depleted uranium) contamination in the environment and possible effects on animal healths in the region o f Bujanovac. Samples of soil, feed, leaves, grass, lichen, moss, honey and water were collected randomly in 2003/2004 in the vicinity of the target area (500-1000 m) and 5 km from the target area. Activity of the radionuclides ( 226 Ra, 232 Th, 40 K, 210 Pb, 238 U, 235 U, 137 Cs, 7 Be) in soils, grass, lichen, moss and honey was determined on Hp Ge detector (Canberra, relative efficiency 23%) by standard gamma spectrometry. Total alpha and beta activity in water was determined on proportional alpha/beta counter (Canberra 2400, efficiency for alpha emitters 11%, efficiency for beta emitters 30%). Non significantly higher values of concentrations of 226 Ra, 232 Th, 238 U and 235 U were measured in the immediate vicinity of the targeted site, but 235 U/ 238 U activity ratio in soils indicated the natural origin of uranium. On both sites the contents of radionuclides in soils were in the range of values measured in soils in Belgrade (2002-2005), at the mountain Stara Planina (1999) and in the region. The soil was found to be poor in potassium. In mosses and lichen, high concentrations of 137 Cs, 7 Be, 226 Ra and 210 Pb were found, while in leaves and grass there were lower concentrations of K, due to soil poor in K. As for uranium, there were no significant variations due to the sites, and 235 U/ 238 U activity ratios were close to values measured in vegetation in the vicinity of power plants 0.07-0.08. In honey, both 238 U and 235 U were below the minimal detectable concentrations. Total alpha and total beta activities measured in water showed no significant differences between the sites, and the obtained values were in range of the permissible values for drinking water in S.M.N. (total alpha activity <0.1 Bq/L, total beta activity <1 Bq/L) Samples of blood of cows and sheep bred in the area were collected

Mortality analyses in the updated French cohort of uranium miners (1946-2007)

Energy Technology Data Exchange (ETDEWEB)

Rage, E.; Caer-Lorho, S.; Drubay, D.; Ancelet, S.; Laurier, D. [Institute for Radiological Protection and Nuclear Safety (IRSN), Fontenay-aux-Roses (France). PRP-HOM, SRBE, LEPID; Laroche, P. [AREVA, Paris La Defense (France). Direction Sante

2015-08-15

The objectives are to analyze mortality risks in the extended follow-up of the French uranium miners' cohort and to examine their potential relation to occupational exposure to ionizing radiation (IR). The total cohort includes 5,086 uranium miners employed in the CEA-COGEMA group and followed up from 1946 to 2007. Vital status, causes of death, and cumulative radon exposures were recorded. The post-55 subcohort includes 3,377 miners first employed after 1955, for whom long-lived radionuclides (LLR) and external gamma-ray exposure were also recorded. External mortality analyses were performed by computing standardized mortality ratios (SMR). Excess relative risks (ERRs) due to IR exposures were estimated from Poisson regression models. The miners included in the total cohort were followed up for 35.4 years and exposed to 36.6 working level months (WLM) on average. There was no evidence of a difference in overall mortality between miners and the general French male population. Miners had a statistically significant excess mortality rate from lung cancer (SMR = 1.34 [95 % CI 1.16-1.53]) and from kidney cancer (SMR = 1.60 [1.03-2.39]). Cumulative radon exposure was significantly associated with lung cancer risk (ERR/100 WLM = 0.71 [0.31-1.30]) and cerebrovascular risk (ERR/100 WLM = 0.41 [0.04-1.03]). In the post-55 subcohort, this excess mortality from lung cancer remained associated with exposure to radon, and also with exposure to LLR and external gamma rays. Conclusions The analyses in the extended follow-up strengthen the results previously observed among French uranium miners about their excess risk of mortality and its association with their occupational IR exposure.

Mortality analyses in the updated French cohort of uranium miners (1946-2007)

International Nuclear Information System (INIS)

Rage, E.; Caer-Lorho, S.; Drubay, D.; Ancelet, S.; Laurier, D.; Laroche, P.

2015-01-01

The objectives are to analyze mortality risks in the extended follow-up of the French uranium miners' cohort and to examine their potential relation to occupational exposure to ionizing radiation (IR). The total cohort includes 5,086 uranium miners employed in the CEA-COGEMA group and followed up from 1946 to 2007. Vital status, causes of death, and cumulative radon exposures were recorded. The post-55 subcohort includes 3,377 miners first employed after 1955, for whom long-lived radionuclides (LLR) and external gamma-ray exposure were also recorded. External mortality analyses were performed by computing standardized mortality ratios (SMR). Excess relative risks (ERRs) due to IR exposures were estimated from Poisson regression models. The miners included in the total cohort were followed up for 35.4 years and exposed to 36.6 working level months (WLM) on average. There was no evidence of a difference in overall mortality between miners and the general French male population. Miners had a statistically significant excess mortality rate from lung cancer (SMR = 1.34 [95 % CI 1.16-1.53]) and from kidney cancer (SMR = 1.60 [1.03-2.39]). Cumulative radon exposure was significantly associated with lung cancer risk (ERR/100 WLM = 0.71 [0.31-1.30]) and cerebrovascular risk (ERR/100 WLM = 0.41 [0.04-1.03]). In the post-55 subcohort, this excess mortality from lung cancer remained associated with exposure to radon, and also with exposure to LLR and external gamma rays. Conclusions The analyses in the extended follow-up strengthen the results previously observed among French uranium miners about their excess risk of mortality and its association with their occupational IR exposure.

Uranium enrichment

International Nuclear Information System (INIS)

1991-11-01

This paper analyzes under four different scenarios the adequacy of a $500 million annual deposit into a fund to pay for the cost of cleaning up the Department of Energy's (DOE) three aging uranium enrichment plants. These plants are located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. In summary the following was found: A fixed annual $500 million deposit made into a cleanup fund would not be adequate to cover total expected cleanup costs, nor would it be adequate to cover expected decontamination and decommissioning (D and D) costs. A $500 million annual deposit indexed to an inflation rate would likely be adequate to pay for all expected cleanup costs, including D and D costs, remedial action, and depleted uranium costs

Geochemical methods for identification of formations being prospective for uranium

International Nuclear Information System (INIS)

Zhukova, A.M.; Komarova, N.I.; Spiridonov, A.A.; Shor, G.M.

1985-01-01

Geochemical methods of uranium content evaluation in metamorphic, ultrametamorphic and sedimentary formations are considered. At that, the following four factors are of the highest importance: 1) average uranium content-geochemical background; 2) character of uranium distribution; 3) forms of uranium presence; 4) the value of thorium-uranium ratio. A complex of radiogeochemical criteria, favourable for uranium presence is formulated: high average background content of total and '' mobile''uranium and high value of variation coefficient (80-100% and above); low (approximately one or lower) thorium-uranium ratio; sharp increase in uranium concentration in accessory minerals. Radiogeochemical peculiarities of metamorphic and ultrametamorphic formations prospective for uranium are enumerated. The peculiarities condition specificity of geochemical prospecting methods. Prospecting methods first of all must be directed at the evaluation of radioelement distribution parameters and specification of the forms of their presence

Practical issues in discriminating between environmental and occupational sources in a uranium urinalysis bioassay program

International Nuclear Information System (INIS)

Long, M.P.; Carbaugh, E.H.; Fairrow, N.L.

1994-11-01

Workers at two Department of Energy facilities, the Pantex Plant in Texas and the Hanford Site in Washington, are potentially exposed to class Y depleted or natural uranium. Since trace amounts of uranium are naturally present in urine excretion, site bioassay programs must be able to discern occupational exposure from naturally occurring uranium exposure. In 1985 Hanford established a 0.2-μg/d environmental screening level for elemental uranium in urine; the protocol was based on log-normal probability analysis of unexposed workers. A second study of background uranium levels commenced in 1990, and experiences in the field indicated that there seemed to be an excessive number of urine samples with uranium above the screening level and that the environmental screening level should be reviewed. Due to unforeseen problems, that second study was terminated before the complete data could be obtained. Natural uranium in rock (by weight, 99.27% 288 U, 0.72% 235 U, and 0.006% 234 U) has approximately equal activity concentrations of 238 U and 234 U. Earlier studies, summarized by the U.S. Environmental Protection Agency in 51 FR 32068, have indicated that 234 U (via 234 Th) has a greater environmental mobility than 238 U and may well have a higher concentration in ground water. By assuming that the 238 U-to 234 U ratio in the urine of nonoccupationally exposed persons should reflect the ratio of environmental levels, significant occupational exposure to depleted uranium would shift that ratio in favor of 238 U, allowing use of the ratio as a co-indicator of occupational exposure in addition to the isotope-specific screening levels. This approach has been adopted by Pantex. The Pacific Northwest Laboratory is studying the feasibility of applying this method to the natural and recycled uranium mixtures encountered at Hanford. The Hanford data included in this report represent work-in-progress

Lung cancer in uranium miners: A tissue resource and pilot study. Final performance report

International Nuclear Information System (INIS)

Samet, J.; Gilliland, F.D.

1998-01-01

This project incorporates two related research projects directed toward understanding respiratory carcinogenesis in radon-exposed former uranium miners. The first project involved a continuation of the tissue resource of lung cancer cases from former underground uranium miners and comparison cases from non-miners. The second project was a pilot study for a proposed longitudinal study of respiratory carcinogenesis in former uranium miners. The objectives including facilitating the investigation of molecular changes in radon exposed lung cancer cases, developing methods for prospectively studying clinical, cytologic, cytogenetic, and molecular changes in the multi-event process of respiratory carcinogenesis, and assessing the feasibility of recruiting former uranium miners into a longitudinal study that collected multiple biological specimens. A pilot study was conducted to determine whether blood collection, induced sputum, bronchial brushing, washings, and mucosal biopsies from participants at two of the hospitals could be included efficiently. A questionnaire was developed for the extended study and all protocols for specimen collection and tissue handling were completed. Resource utilization is in progress at ITRI and the methods have been developed to study molecular and cellular changes in exfoliated cells contained in sputum as well as susceptibility factors

Lung cancer in uranium miners: A tissue resource and pilot study. Final performance report

Energy Technology Data Exchange (ETDEWEB)

Samet, J.; Gilliland, F.D.

1998-08-13

This project incorporates two related research projects directed toward understanding respiratory carcinogenesis in radon-exposed former uranium miners. The first project involved a continuation of the tissue resource of lung cancer cases from former underground uranium miners and comparison cases from non-miners. The second project was a pilot study for a proposed longitudinal study of respiratory carcinogenesis in former uranium miners. The objectives including facilitating the investigation of molecular changes in radon exposed lung cancer cases, developing methods for prospectively studying clinical, cytologic, cytogenetic, and molecular changes in the multi-event process of respiratory carcinogenesis, and assessing the feasibility of recruiting former uranium miners into a longitudinal study that collected multiple biological specimens. A pilot study was conducted to determine whether blood collection, induced sputum, bronchial brushing, washings, and mucosal biopsies from participants at two of the hospitals could be included efficiently. A questionnaire was developed for the extended study and all protocols for specimen collection and tissue handling were completed. Resource utilization is in progress at ITRI and the methods have been developed to study molecular and cellular changes in exfoliated cells contained in sputum as well as susceptibility factors.

An analysis of uranium dispersal and health effects using a Gulf War case study

International Nuclear Information System (INIS)

Marshall, Albert Christian

2005-01-01

The study described in this report used mathematical modeling to estimate health risks from exposure to depleted uranium (DU) during the 1991 Gulf War for both U.S. troops and nearby Iraqi civilians. The analysis found that the risks of DU-induced leukemia or birth defects are far too small to result in an observable increase in these health effects among exposed veterans or Iraqi civilians. Only a few veterans in vehicles accidentally struck by U.S. DU munitions are predicted to have inhaled sufficient quantities of DU particulate to incur any significant health risk (i.e., the possibility of temporary kidney damage from the chemical toxicity of uranium and about a 1% chance of fatal lung cancer). The health risk to all downwind civilians is predicted to be extremely small. Recommendations for monitoring are made for certain exposed groups. Although the study found fairly large calculational uncertainties, the models developed and used are generally valid. The analysis was also used to assess potential uranium health hazards for workers in the weapons complex. No illnesses are projected for uranium workers following standard guidelines; nonetheless, some research suggests that more conservative guidelines should be considered

An analysis of uranium dispersal and health effects using a Gulf War case study.

Energy Technology Data Exchange (ETDEWEB)

Marshall, Albert Christian

2005-07-01

The study described in this report used mathematical modeling to estimate health risks from exposure to depleted uranium (DU) during the 1991 Gulf War for both U.S. troops and nearby Iraqi civilians. The analysis found that the risks of DU-induced leukemia or birth defects are far too small to result in an observable increase in these health effects among exposed veterans or Iraqi civilians. Only a few veterans in vehicles accidentally struck by U.S. DU munitions are predicted to have inhaled sufficient quantities of DU particulate to incur any significant health risk (i.e., the possibility of temporary kidney damage from the chemical toxicity of uranium and about a 1% chance of fatal lung cancer). The health risk to all downwind civilians is predicted to be extremely small. Recommendations for monitoring are made for certain exposed groups. Although the study found fairly large calculational uncertainties, the models developed and used are generally valid. The analysis was also used to assess potential uranium health hazards for workers in the weapons complex. No illnesses are projected for uranium workers following standard guidelines; nonetheless, some research suggests that more conservative guidelines should be considered.

Health physics in the Novazza (Bergamo, Italy) uranium mine

International Nuclear Information System (INIS)

Bassignani, S.; Fenzi, A.; Turchi, A.

1979-01-01

In this article the potential radiological hazards due to internal and external exposure of workers in the Novazza uranium mine are considered, as well as the surveillance systems adopted into the mine galleries from the current pre-operational stage. The problem is outlined of assuming for the professionally exposed workers an exposure limit allowing to reduce the hazards to negligible levels, taking the operational requirements into account. Finally, a summary of the daily measurements of radon daughters is presented, together with the methods currently applied in the estimate of the radiological impact of the uranium mine on the environment

Reaction of water vapor with a clean liquid uranium surface

International Nuclear Information System (INIS)

Siekhaus, W.

1985-01-01

To study the reaction of water vapor with uranium, we have exposed clean liquid uranium surfaces to H 2 O under UHV conditions. We have measured the surface concentration of oxygen as a function of exposure, and determined the maximum attainable surface oxygen concentration X 0 /sup s/ as a function of temperature. We have used these measurements to estimate, close to the melting point, the solubility of oxygen (X 0 /sup b/, -4 ) and its surface segregation coefficient β/sup s/(> 10 3 ). 8 refs., 5 figs., 1 tab

A cohort study of uranium millers and miners of Grants, New Mexico, 1979-2005

International Nuclear Information System (INIS)

Boice, John D Jr; Cohen, Sarah S; Mumma, Michael T; Chadda, Bandana; Blot, William J

2008-01-01

A cohort mortality study of workers engaged in uranium milling and mining activities near Grants, New Mexico, during the period from 1955 to 1990 was conducted. Vital status was determined through 2005 and standardised mortality ratio (SMR) analyses were conducted for 2745 men and women alive after 1978 who were employed for at least six months. Overall, mortality from all causes (SMR 1.15; 95% CI 1.07-1.23; n = 818) and all cancers (SMR 1.22; 95% CI 1.07-1.38; n = 246) was greater than expected on the basis of US mortality rates. Increased mortality, however, was seen only among the 1735 underground uranium miners and was due to malignant (SMR 2.17; 95% CI 1.75-2.65; n = 95) and non-malignant (SMR 1.64; 95% CI 1.23-2.13; n = 55) respiratory diseases, cirrhosis of the liver (SMR 1.79; n = 18) and external causes (SMR 1.65; n = 58). The lung cancer excess likely is attributable to the historically high levels of radon in uranium mines of the Colorado Plateau, combined with the heavy use of tobacco products. No statistically significant elevation in any cause of death was seen among the 904 non-miners employed at the Grants uranium mill. Among 718 mill workers with the greatest potential for exposure to uranium ore, no statistically significant increase in any cause of death of a priori interest was seen, i.e., cancers of the lung, kidney, liver, or bone, lymphoma, non-malignant respiratory disease, renal disease or liver disease. Although the population studied was relatively small, the follow-up was long (up to 50 yrs) and complete. In contrast to miners exposed to radon and radon decay products, for uranium mill workers exposed to uranium dusts and mill products there was no clear evidence of uranium-related disease

Studies on kidney function in workers exposed to uranium contamination

International Nuclear Information System (INIS)

Bugueno, M.C.; Suarez, J.

1983-01-01

The values of some kidney function tests in our workers were studied through the media, range and statistical spread, compared with those used abroad and also in our main hospitals. With that purpose, thirty three personas were selected among those without kidney pathology history of uranium internal contamination as revealed by the permanent control of our clinical and radiotoxicological service. Kidney function was explored through the measurement of uremia, ureic nitrogen, albuminuria, endogenous creatinine clearance and the Addis test. Values determined were normal with respect to those used in the international literature, with the exception of the creatinine clearance test. Also a 6% of our workers were abnormal in at least one or two of the five tests employed. (Author)

Micronuclei in lymphocytes from currently active uranium miners

International Nuclear Information System (INIS)

Zoelzer, Friedo; Freitinger Skalicka, Zuzana; Havrankova, Renata; Hon, Zdenek; Rosina, Jozef; Navratil, Leos; Skopek, Jiri

2012-01-01

Micronuclei can be used as markers of past radiation exposure, but only few studies have dealt with uranium miners. In this paper, we report on micronuclei in lymphocytes from individuals currently working at Rozna, Czech Republic, the last functioning uranium mine in the European Union. A modified micronucleus-centromere test was applied to assess the occurrence of micronuclei in stimulated lymphocytes, as well as their content in terms of whole chromosomes or fragments. Compared with unexposed individuals, the miners had higher frequencies of micronucleus-containing lymphocytes and higher percentages of micronuclei without centromeres, and the differences were significant for both parameters (0.74 ± 0.60 vs. 0.50 ± 0.42, p = 0.017 and 49 ± 44 vs. 12 ± 21, p = 0.0002; means ± standard deviations). There were also significant correlations between one or other of these parameters on the one hand and various dose values on the other, in particular with a 'retrievable' dose, that is, a dose whose effect should still be recognisable in lymphocytes assuming a half-life of 3 years. The 'retrievable' dose at which a doubling of the micronucleus frequency was observed was around 35 mSv, corresponding to a total dose of 90 mSv received while working in the mines. Altogether, our data show that the micronucleus-centromere test is a valuable tool for the assessment of past radiation exposure in uranium miners. The scatter in the data is of course far too great to allow individual dosimetry, but for groups of a few dozen exposed individuals, the method can be used to monitor doses clearly below 100 mSv. (orig.)

Uranium from German nuclear power projects of the 1940s - a nuclear forensic investigation

Energy Technology Data Exchange (ETDEWEB)

Mayer, Klaus; Wallenius, Maria; Luetzenkirchen, Klaus; Horta, Joan; Nicholl, Adrian; Rasmussen, Gert; Belle, Pieter van; Varga, Zsolt [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Karlsruhe (Germany); Buda, Razvan; Erdmann, Nicole [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Karlsruhe (Germany); Institut fuer Kernchemie, Universitaet Mainz (Germany); Kratz, Jens-Volker; Trautmann, Norbert [Institut fuer Kernchemie, Universitaet Mainz (Germany); Fifield, L. Keith; Tims, Stephen G. [Department of Nuclear Physics, Research School of Physics and Engineering, The Australian National University, Canberra, ACT (Australia); Froehlich, Michaela B. [Department of Nuclear Physics, Research School of Physics and Engineering, The Australian National University, Canberra, ACT (Australia); Universitaet Wien, Fakultaet fuer Chemie, Institut fuer Anorganische Chemie, Vienna (Austria); Steier, Peter [Universitaet Wien, Fakultaet fuer Physik, Isotopenforschung und Kernphysik, Vienna (Austria)

2015-11-02

Here we present a nuclear forensic study of uranium from German nuclear projects which used different geometries of metallic uranium fuel. Through measurement of the {sup 230}Th/{sup 234}U ratio, we could determine that the material had been produced in the period from 1940 to 1943. To determine the geographical origin of the uranium, the rare-earth-element content and the {sup 87}Sr/{sup 86}Sr ratio were measured. The results provide evidence that the uranium was mined in the Czech Republic. Trace amounts of {sup 236}U and {sup 239}Pu were detected at the level of their natural abundance, which indicates that the uranium fuel was not exposed to any major neutron fluence. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Experimental study on uranium alloys for hydrogen storage

International Nuclear Information System (INIS)

Deaconu, M.; Meleg, T.; Dinu, A.; Mihalache, M.; Ciuca, I.; Abrudeanu, M.

2013-01-01

The heaviest isotope of hydrogen is one of critically important elements in the field of fusion reactor technology. Conventionally, uranium metal is used for the storage of heavier isotopes of hydrogen (D and T). Under appropriate conditions, uranium absorbs hydrogen to form a stable UH 3 compound when exposed to molecular hydrogen at the temperature range of 300-500 O C at varied operating pressure below one atmosphere. However, hydriding-dehydriding on pure uranium disintegrates the specimen into fine powder. The powder is highly pyrophoric and has low heat conductivity, which makes it difficult to control the temperature, and has a high possibility of contamination Due to the powdering effect as hydrogen in uranium, alloying uranium with other metal looks promising for the use of hydrogen storage materials. This paper has the aim to study the hydriding properties of uranium alloys, including U-Ti U-Mo and U-Ni. The uranium alloys specimens were prepared by melting the constituent elements by means of simultaneous measurements of thermo-gravimetric and differential thermal analyses (TGA-DTA) and studied in as cast condition as hydrogen storage materials. Then samples were thermally treated under constant flow of hydrogen, at various temperatures between 573-973 0 K. The structural and absorption properties of the products obtained were examined by thermo-gravimetric analysis (TG), X-ray diffraction (XRD) and scanning electron microscopy (SEM). They slowly reacted with hydrogen to form the ternary hydride and the hydrogenated samples mainly consisted of the pursued ternary hydride bat contained also U or UO 2 and some transient phase. (authors)

Effectiveness of chelation therapy with time after acute uranium intoxication

International Nuclear Information System (INIS)

Domingo, J.L.; Ortega, A.; Llobet, J.M.; Corbella, J.

1990-01-01

The effect of increasing the time interval between acute uranium exposure and chelation therapy was studied in male Swiss mice. Gallic acid, 4,5-dihydroxy-1,3- benzenedisulfonic acid (Tiron), diethylenetriaminepentaacetic acid (DTPA), and 5-aminosalicylic acid (5-AS) were administered ip at 0, 0.25, 1, 4, and 24 hr after sc injection of 10 mg/kg of uranyl acetate dihydrate. Chelating agents were given at doses equal to one-fourth of their respective LD50 values. Daily elimination of uranium into urine and feces was determined for 4 days after which time the mice were killed, and the concentration of uranium was measured in kidney, spleen, and bone. The excretion of uranium was especially rapid in the first 24 hr. Treatment with Tiron or gallic acid at 0, 0.25, or 1 hr after uranium exposure significantly increased the total excretion of the metal. In kidney and bone, only administration of Tiron at 0, 0.25, or 1 hr after uranium injection, or gallic acid at 1 hr after uranium exposure significantly reduced tissue uranium concentrations. Treatment at later times (4 to 24 hr) did not increase the total excretion of the metal and did not decrease the tissue uranium concentrations 4 days after uranyl acetate administration. The results show that the length of time before initiating chelation therapy for acute uranium intoxication greatly influences the effectiveness of this therapy

Progress in recovery technology for uranium from seawater

International Nuclear Information System (INIS)

Sugo, Takanobu; Saito, Kyoichi.

1994-01-01

By the facts that the research group in Japan improved the performance of amidoxime resin which is the adsorbent for collecting seawater uranium, proposed the method of mooring floating bodies utilizing sea current and waves as the adsorption system, and further, verified the results of laboratory basic experiment by marine experiment, the technology of collecting seawater uranium has progressed. After the oil crisis, various countries started the research on seawater uranium, but only Japan has continued the systematic study up to now. In this report, the research on seawater uranium collection carried out so far is summarized, and the characteristics of the adsorbent which was synthesized by radiation graft polymerization and the results of the uranium collection test using coastal seawater are reported. In seawater of 1 m 3 , the uranium of 3.3 mg is dissolved in the form of uranyl tricarbonate complex ions. In the total quantity of seawater, the dissolved uranium amounts to about 4.6 billion tons, about 1000 times of the uranium resources on land. The research on seawater uranium collection and the performance of uranium adsorption of synthesized amidoxime fibers are reported. (K.I.)

Natural uranium toxicology - evaluation of internal contamination in man; Toxicologie de l'uranium naturel - essai d'evaluation de la contamination interne chez l'homme

Energy Technology Data Exchange (ETDEWEB)

Chalabreysse, J [Commissariat a l' Energie Atomique, Pierrelatte (France). Centre d' Etudes Nucleaires

1968-07-01

After reminding the physical and chemical properties of natural uranium which might affect its toxicology, a comprehensive investigation upon natural uranium metabolism and toxicity and after applying occupational exposure standards to this particular poison, it has been determined, from accident reports and human experience reported in the related literature, a series of formulae obtained by theoretical mathematical development giving principles for internal contamination monitoring and disclosure by determining uranium in the urine of occupationally exposed individuals. An assay is performed to determine individual internal contamination according to the various contamination cases. The outlined purposes, mainly practical, required some options and extrapolations. The proposed formula allows a preliminary approach and also to determine shortly a contamination extent or to discuss the systematical urinalysis results as compared with individual radio-toxicology monitoring professional standards. (author) [French] Apres le rappel des caracteristiques physiques et des proprietes chimiques de l'uranium naturel pouvant avoir une influence sur sa toxicologie, l'etude detaillee de son metabolisme et de sa toxicite, puis l'application des normes professionnelles d'exposition au cas particulier de ce toxique, il est etabli, a partir des comptes rendus d'accidents et de l'experimentation humaine rapportes dans la litterature, une serie de formules obtenues par developpement mathematique theorique qui posent les principes de la surveillance et de la mise en evidence de la contamination interne par la recherche et le dosage de l'uranium dans les urines d'individus professionnellement exposes. Un essai d'evaluation de la contamination interne individuelle suivant les differents cas de contamination est effectue. Le formulaire propose permet de faire une premiere approximation et d'apprecier rapidement l'importance d'une contamination ou bien d'interpreter les resultats d

Hydrothermal uranium deposits containing molybdenum and fluorite in the Marysvale volcanic field, west-central Utah

Science.gov (United States)

Cunningham, C.G.; Rasmussen, J.D.; Steven, T.A.; Rye, R.O.; Rowley, P.D.; Romberger, S.B.; Selverstone, J.

1998-01-01

Uranium deposits containing molybdenum and fluorite occur in the Central Mining Area, near Marysvale, Utah, and formed in an epithermal vein system that is part of a volcanic/hypabyssal complex. They represent a known, but uncommon, type of deposit; relative to other commonly described volcanic-related uranium deposits, they are young, well-exposed and well-documented. Hydrothermal uranium-bearing quartz and fluorite veins are exposed over a 300 m vertical range in the mines. Molybdenum, as jordisite (amorphous MoS2, together with fluorite and pyrite, increase with depth, and uranium decreases with depth. The veins cut 23-Ma quartz monzonite, 20-Ma granite, and 19-Ma rhyolite ash-flow tuff. The veins formed at 19-18 Ma in a 1 km2 area, above a cupola of a composite, recurrent, magma chamber at least 24 ?? 5 km across that fed a sequence of 21- to 14-Ma hypabyssal granitic stocks, rhyolite lava flows, ash-flow tuffs, and volcanic domes. Formation of the Central Mining Area began when the intrusion of a rhyolite stock, and related molybdenite-bearing, uranium-rich, glassy rhyolite dikes, lifted the fractured roof above the stock. A breccia pipe formed and relieved magmatic pressures, and as blocks of the fractured roof began to settle back in place, flat-lying, concave-downward, 'pull-apart' fractures were formed. Uranium-bearing, quartz and fluorite veins were deposited by a shallow hydrothermal system in the disarticulated carapace. The veins, which filled open spaces along the high-angle fault zones and flat-lying fractures, were deposited within 115 m of the ground surface above the concealed rhyolite stock. Hydrothermal fluids with temperatures near 200??C, ??18OH2O ~ -1.5, ?? -1.5, ??DH2O ~ -130, log fO2 about -47 to -50, and pH about 6 to 7, permeated the fractured rocks; these fluids were rich in fluorine, molybdenum, potassium, and hydrogen sulfide, and contained uranium as fluoride complexes. The hydrothermal fluids reacted with the wallrock resulting in

The uranium resources and production of Namibia

International Nuclear Information System (INIS)

Palfi, A.G.

1997-01-01

The promulgation of the Minerals (Prospecting and Mining) Act, 1992, on 1 April 1994 and the simultaneous repeal of restrictive South African legislation on reporting uranium exploration and production results, allowed the Namibian Government for the first time to present information for publication of the report ''Uranium 1995 - Resource, Production and Demand'', by the OECD Nuclear Energy Agency and the IAEA. Namibia, one of the youngest independent nations in Africa, has a large number of uranium occurrences and deposits in several geological environments. The total estimated uranium resource amounts to about 299 thousand tonnes recoverable uranium at a cost of less than US$ 130/kg U, within the known conventional resources category. The most prominent geological type of these is the unique, granite-related uranium occurrences located in the central part of the Namib Desert. Permo-Triassic age Karoo sandstone-hosted uranium deposits were subject to only limited exploration due to the down-turn of uranium prices in the latter part of 1980s, despite they very encouraging exploration results. As only limited Karoo sandstone-covered areas were tested there is still great potential for further discoveries. The planned output of Roessing Uranium Mine at 40,000 tonnes of ore per day which results in an annual production of 4536 tonnes of uranium oxide, was achieved in 1979. In case of improved uranium market conditions, Namibia is in a strong position to increase uranium production and open up new production centres to strengthen the country's position as an important uranium producer in the world. 6 figs, 2 tabs

Imouraren - uranium leaching tests and specificities with analcites

International Nuclear Information System (INIS)

Wattinne-Morice, A.; Belieres, M.

2010-01-01

Imouraren is a sedimentary uranium deposit (total > 150 000 tU, average U ~ 0.08 %), located in Niger (~ 100 km from Agadez). Uranium mineralization is trapped in sandstones and is widely oxidized (uranotyle, metatuyamunite), but a part remains reduced (pitchblende, uraninite). The sandstones have a peculiar mineralogical assemblage (analcite partly chloritized) which can affect uranium recovery. Several acid heap leaching tests have been completed to determine the most suitable process parameters. Microscopic studies and XRD analysis performed on fresh ore and on leached residue highlight the complex behavior of uranium and the associated mineralogical families during the tests. (author)

Late-occurring pulmonary pathologies following inhalation of mixed oxide (uranium + plutonium oxide) aerosol in the rat.

Science.gov (United States)

Griffiths, N M; Van der Meeren, A; Fritsch, P; Abram, M-C; Bernaudin, J-F; Poncy, J L

2010-09-01

Accidental exposure by inhalation to alpha-emitting particles from mixed oxide (MOX: uranium and plutonium oxide) fuels is a potential long-term health risk to workers in nuclear fuel fabrication plants. For MOX fuels, the risk of lung cancer development may be different from that assigned to individual components (plutonium, uranium) given different physico-chemical characteristics. The objective of this study was to investigate late effects in rat lungs following inhalation of MOX aerosols of similar particle size containing 2.5 or 7.1% plutonium. Conscious rats were exposed to MOX aerosols and kept for their entire lifespan. Different initial lung burdens (ILBs) were obtained using different amounts of MOX. Lung total alpha activity was determined by external counting and at autopsy for total lung dose calculation. Fixed lung tissue was used for anatomopathological, autoradiographical, and immunohistochemical analyses. Inhalation of MOX at ILBs ranging from 1-20 kBq resulted in lung pathologies (90% of rats) including fibrosis (70%) and malignant lung tumors (45%). High ILBs (4-20 kBq) resulted in reduced survival time (N = 102; p inhalation result in similar risk for development of lung tumors as compared with industrial plutonium oxide.

Uranium conversion

International Nuclear Information System (INIS)

Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina

2006-03-01

FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF 6 and UF 4 are present require equipment that is made of corrosion resistant material

Results of uranium HSSR survey of the San Juan area southwestern Colorado

International Nuclear Information System (INIS)

Maxwell, J.C.

1977-01-01

During June--July 1976, 1706 water samples and 1982 sediment samples were collected from 1995 sites in the San Juan Mountains area and analyzed for uranium. The area includes the southern third of the Colorado mineral belt which has yielded rich ores of gold, silver, copper, lead, zinc, and molybdenum. The broadly domed mountains are capped by 2500 m of Tertiary volcanics, deeply eroded to expose a Precambrian crystalline core. Adjacent plateaus underlain by Mesozoic sedimentary rocks were included in the reconnaissance. Average value of uranium in water samples from mountains was less than 0.5 ppB, from plateaus was 1 to 2 ppB, and from Mancos shale areas exceeded 2 ppB. Anomalous sediment samples, 40 ppM uranium, came from near Storm King Mountain and upper Vallecito Creek. Other anomalous areas, including the Lake City mining district, were well defined by 4 to 30 ppM uranium in sediment and 3 to 30 ppB uranium in water. Above-average concentrations of uranium not previously reported indicate areas favorable for detailed exploration

Real-Time Speciation of Uranium During Active Bioremediation and U(IV) Reoxidation

International Nuclear Information System (INIS)

Komlos, J.; Mishra, B.; Lanzirotti, A.; Myneni, S.; Jaffe, P.

2008-01-01

The biological reduction of uranium from soluble U(VI) to insoluble U(IV) has shown potential to prevent uranium migration in groundwater. To gain insight into the extent of uranium reduction that can occur during biostimulation and to what degree U(IV) reoxidation will occur under field relevant conditions after biostimulation is terminated, X-ray absorption near edge structure (XANES) spectroscopy was used to monitor: (1) uranium speciation in situ in a flowing column while active reduction was occurring; and (2) in situ postbiostimulation uranium stability and speciation when exposed to incoming oxic water. Results show that after 70 days of bioreduction in a high (30 mM) bicarbonate solution, the majority (>90%) of the uranium in the column was immobilized as U(IV). After acetate addition was terminated and oxic water entered the column, in situ real-time XANES analysis showed that U(IV) reoxidation to U(VI) (and subsequent remobilization) occurred rapidly (on the order of minutes) within the reach of the oxygen front and the spatial and temporal XANES spectra captured during reoxidation allowed for real-time uranium reoxidation rates to be calculated.

Machining of uranium and uranium alloys

International Nuclear Information System (INIS)

Morris, T.O.

1981-01-01

Uranium and uranium alloys can be readily machined by conventional methods in the standard machine shop when proper safety and operating techniques are used. Material properties that affect machining processes and recommended machining parameters are discussed. Safety procedures and precautions necessary in machining uranium and uranium alloys are also covered. 30 figures

Lung cancer among workers at a uranium processing plant

International Nuclear Information System (INIS)

Cookfair, D.L.; Beck, W.L.; Shy, C.; Lushbaugh, C.C.; Sowder, C.L.

1983-01-01

This study examined the risk of dying from lung cancer among white males who received radiation to the lung as a result of inhaling uranium dust or the dust of uranium compounds. Cases and controls were chosen from a cohort of workers employed in a uranium processing plant during World War II. Cumulative radiation lung dose among study population members ranged from 0 to 75 rads. Relative risk was found to increase with increasing level of exposure even after controlling for age and smoking status, but only for those who were over the age of 45 when first exposed. A statistically significant excess in risk was found for men in this age group with a cumulative lung dose of 20 rads of more. These data suggest that older age groups may be more susceptible to radiation-induced lung cancer than younger age groups

Uranium recovery from slags of metallic uranium

International Nuclear Information System (INIS)

Fornarolo, F.; Frajndlich, E.U.C.; Durazzo, M.

2006-01-01

The Center of the Nuclear Fuel of the Institute of Nuclear Energy Research - IPEN finished the program of attainment of fuel development for research reactors the base of Uranium Scilicet (U 3 Si 2 ) from Hexafluoride of Uranium (UF 6 ) with enrichment 20% in weight of 235 U. In the process of attainment of the league of U 3 Si 2 we have as Uranium intermediate product the metallic one whose attainment generates a slag contend Uranium. The present work shows the results gotten in the process of recovery of Uranium in slags of calcined slags of Uranium metallic. Uranium the metallic one is unstable, pyrophoricity and extremely reactive, whereas the U 3 O 8 is a steady oxide of low chemical reactivity, what it justifies the process of calcination of slags of Uranium metallic. The calcination of the Uranium slag of the metallic one in oxygen presence reduces Uranium metallic the U 3 O 8 . Experiments had been developed varying it of acid for Uranium control and excess, nitric molar concentration gram with regard to the stoichiometric leaching reaction of temperature of the leaching process. The 96,0% income proves the viability of the recovery process of slags of Uranium metallic, adopting it previous calcination of these slags in nitric way with low acid concentration and low temperature of leaching. (author)

Uranium, depleted uranium, biological effects; Uranium, uranium appauvri, effets biologiques

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

Physicists, chemists and biologists at the CEA are developing scientific programs on the properties and uses of ionizing radiation. Since the CEA was created in 1945, a great deal of research has been carried out on the properties of natural, enriched and depleted uranium in cooperation with university laboratories and CNRS. There is a great deal of available data about uranium; thousands of analyses have been published in international reviews over more than 40 years. This presentation on uranium is a very brief summary of all these studies. (author)

Continued studies of long-term ecological effects of exposure to uranium

Energy Technology Data Exchange (ETDEWEB)

Hanson, W.C.; Miera, F.R. Jr.

1977-06-01

Studies of the long-term consequences of exposing terrestrial ecosystems to natural and depleted uranium dispersed during explosives tests at Los Alamos Scientific Laboratory (LASL) and test firing at Eglin Air Force Base (EAFB), Florida, were continued. Soils from EAFB, sampled before and after firing of depleted uranium penetrators against armor plate targets, indicated that the upper (0- to 5-cm-deep) soil usually contained more uranium than lower (5- to 10-cm-deep) soil. However, no significant changes were apparent in samples taken before and after the test firing. E-F explosive testing site at LASL was selected for intensive study of uranium redistribution during its 33-yr use. Highest surface soil (0- to 2.5-cm-deep) uranium concentrations occurred 0 and 10 m from the detonation point and averaged 4500 ppM. Concentrations in surface soil 50 and 200 m from the firing point were usually < 15% of that value. The uranium distribution to 30-cm depths showed significant penetration into the soil. Alluvium collected 250 m from the E-F detonation area in Potrillo Canyon indicated that surface (0- to 2.5-cm-deep) uranium concentrations were about 10% of those at the detonation point, and at 2.8 km they were twice background levels.

Pro-oxidant effects in the brain of rats concurrently exposed to uranium and stress

International Nuclear Information System (INIS)

Linares, Victoria; Sanchez, Domenec J.; Belles, Montserrat; Albina, Luisa; Gomez, Mercedes; Domingo, Jose L.

2007-01-01

Metal toxicity may be associated with increased rates of reactive oxygen species (ROS) generation within the central nervous system (CNS). Although the kidney is the main target organ for uranium (U) toxicity, this metal can also accumulate in brain. In this study, we investigated the modifications on endogenous antioxidant capacity and oxidative damage in several areas of the brain of U-exposed rats. Eight groups of adult male rats received uranyl acetate dihydrate (UAD) in the drinking water at 0, 10, 20, and 40 mg/kg/day for 3 months. Animals in four groups were concurrently subjected to restraint stress during 2 h/day throughout the study. At the end of the experimental period, cortex, hippocampus and cerebellum were removed and processed to examine the following stress markers: reduced glutathione (GSH), oxidized glutathione (GSSG), glutathione reductase (GR), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive substances (TBARS), as well as U concentrations. The results show that U significantly accumulated in hippocampus, cerebellum and cortex after 3 months of exposure. Moreover, UAD exposure promoted oxidative stress in these cerebral tissues. In cortex and cerebellum, TBARS levels were positively correlated with the U content, while in cerebellum GSSG and GSH levels were positively and negatively correlated, respectively, with U concentrations. In hippocampus, CAT and SOD activities were positively correlated with U concentration. The present results suggest that chronic oral exposure to UAD can cause progressive perturbations on physiological brain levels of oxidative stress markers. Although at the current UAD doses restraint scarcely showed additional adverse effects, its potential influence should not be underrated

Inhibition of poly(ADP-ribose)polymerase-1 and DNA repair by uranium.

Science.gov (United States)

Cooper, Karen L; Dashner, Erica J; Tsosie, Ranalda; Cho, Young Mi; Lewis, Johnnye; Hudson, Laurie G

2016-01-15

Uranium has radiological and non-radiological effects within biological systems and there is increasing evidence for genotoxic and carcinogenic properties attributable to uranium through its heavy metal properties. In this study, we report that low concentrations of uranium (as uranyl acetate; uranium exacerbates DNA damage and cytotoxicity induced by hydrogen peroxide, suggesting that uranium may inhibit DNA repair processes. Concentrations of uranyl acetate in the low micromolar range inhibited the zinc finger DNA repair protein poly(ADP-ribose) polymerase (PARP)-1 and caused zinc loss from PARP-1 protein. Uranyl acetate exposure also led to zinc loss from the zinc finger DNA repair proteins Xeroderma Pigmentosum, Complementation Group A (XPA) and aprataxin (APTX). In keeping with the observed inhibition of zinc finger function of DNA repair proteins, exposure to uranyl acetate enhanced retention of induced DNA damage. Co-incubation of uranyl acetate with zinc largely overcame the impact of uranium on PARP-1 activity and DNA damage. These findings present evidence that low concentrations of uranium can inhibit DNA repair through disruption of zinc finger domains of specific target DNA repair proteins. This may provide a mechanistic basis to account for the published observations that uranium exposure is associated with DNA repair deficiency in exposed human populations. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparison of open cycles of uranium and mixed oxides of thorium-uranium using advanced reactors

International Nuclear Information System (INIS)

Gonçalves, Letícia C.; Maiorino, José R.

2017-01-01

A comparative study of the mass balance and production costs of uranium oxide fuels was carried out for an AP1000 reactor and thorium-uranium mixed oxide in a reactor proposal using thorium called AP-Th1000. Assuming the input mass values for a fuel load the average enrichment for both reactors as well as their feed mass was determined. With these parameters, the costs were calculated in each fuel preparation process, assuming the prices provided by the World Nuclear Association. The total fuel costs for the two reactors were quantitatively compared with 18-month open cycle. Considering enrichment of 20% for the open cycle of mixed U-Th oxide fuel, the total uranium consumption of this option was 50% higher and the cost due to the enrichment was 70% higher. The results show that the use of U-Th mixed oxide fuels can be advantageous considering sustainability issues. In this case other parameters and conditions should be investigated, especially those related to fuel recycling, spent fuel storage and reduction of the amount of transuranic radioactive waste

Natural and depleted uranium in the topsoil of Qatar: Is it something to worry about?

International Nuclear Information System (INIS)

Shomar, Basem; Amr, Mohamed; Al-Saad, Khalid; Mohieldeen, Yasir

2013-01-01

Highlights: • Scientific studies on Uranium in the arid environment are almost absent. • Qatar is closed to Iraq and Iran where the two countries were exposed to long wars. • The paper introduces baseline study integrates chemistry, instrumentation and GIS mapping. • The study opens new horizons for similar studies on the field using similar approach. - Abstract: This study examines uranium in soils of Qatar to investigate whether there is any detectable traces of depleted uranium (DU). 409 soil samples were collected using a 10 km grid system throughout the State of Qatar. The U concentrations and isotopic compositions ( 235 U/ 238 U) were determined using an ICP-MS. The U concentrations range from 0.05 to 4.7 mg/kg and the 235 U/ 238 U isotopic signatures are in the range 0.007–0.008, i.e. comparable to the isotopic ratio in natural uranium (NU). The distribution of these concentrations in the topsoil were used to see correlations with locations of pollution point sources and environmentally hot areas associated with human activity: industrial estates, solid waste dumping sites, wastewater treatment plants, sea harbors, airports, and public transport network. New thematic maps were built using Geographic Information System (GIS) software. The results showed that there is no linkage between the occurrence, distribution, concentrations and isotopic ratios of U and these hotspots. More importantly, due to the low concentration of organic matter (OM) in soils of Qatar, very limited P-fertilization, the alkaline nature of soil (pH 8) and low Fe/Mn contents make soil uranium concentrations very low. The residential areas, including the capital Doha, had the lowest total concentrations of uranium and isotopic ratios of the country while the northern and western parts showed the highest values

Considerations and data on the uranium deposits in West-Mecsek Mountains, Hungary

International Nuclear Information System (INIS)

Erdi-Krausz, G.; Harsanyi, L.

1999-01-01

In 1987, the Government of Hungary closed the uranium mining in the Mecsek Mountain. Data are presented on the uranium reserves in the abandoned site of West-Mecsek. The history of uranium mining and the total amount of produced uranium are up to 31 December 1997 is presented. Some countries in Europe also abandon uranium mining, others develop it (Ukraine, Russia, Kazakhstan, Canada, Australia etc.). The Hungarian uranium reserves should be registered as a part of the national assets. (R.P.)

Can we predict uranium bioavailability based on soil parameters? Part 2: soil solution uranium concentration is not a good bioavailability index.

Science.gov (United States)

Vandenhove, H; Van Hees, M; Wannijn, J; Wouters, K; Wang, L

2007-01-01

The present study aimed to quantify the influence of soil parameters on uranium uptake by ryegrass. Ryegrass was established on eighteen distinct soils, spiked with (238)U. Uranium soil-to-plant transfer factors (TF) ranged from 0.0003 to 0.0340kgkg(-1). There was no significant relation between the U soil-to-plant transfer (or total U uptake or flux) and the uranium concentration in the soil solution or any other soil factor measured, nor with the U recovered following selective soil extractions. Multiple linear regression analysis resulted in a significant though complex model explaining up to 99% of variation in TF. The influence of uranium speciation on uranium uptake observed was featured: UO(2)(+2), uranyl carbonate complexes and UO(2)PO(4)(-) seem the U species being preferentially taken up by the roots and transferred to the shoots. Improved correlations were obtained when relating the uranium TF with the summed soil solution concentrations of mentioned uranium species.

Introduction - Physicochemical and technological aspects of processing of uranium industry wastes in Tajikistan

International Nuclear Information System (INIS)

Khakimov, N.; Nazarov, Kh.M.; Mirsaidov, I.U.

2011-01-01

The uranium deposits of Tajikistan played an immensely significant role in the practical solution of a radioactive raw materials problem which appeared during the post-World War II years in the USSR. The pioneer in this field became complex №6 (currently known as 'Vostokredmet'). The first soviet uranium was produced from the ores extracted from the republic's deposits. For 50 years (1945-1995 y.) , uranium bearing raw materials from all over the former USSR were delivered to Tajikistan, and uranium oxide was produced, which was later delivered back to Russia for further production of enriched uranium. The total volume of uranium produced in Tajikistan plants was approximately 100 thousands tons. In Soghd region, during that period, more than 55 million tons of uranium waste was accumulated. The total activity of the waste, according to different calculations, is approximately 240-285 TBq. The total amount of waste in dumps and tailings piles is estimated to be more than 170 million tons, most of which are located in the neighborhoods of hydrometallurgical plants and heap leaching locations. Uranium industry wastes in Northern Tajikistan have become attractive for different investors and commercial companies, from secondary reprocessing of mines and tailings' point of view, since the uranium price is increasing. In this regard, research on developing uranium extraction methods from wastes is broadening. The study of the possibility and economic reasonability of reprocessing former year's dumps requires comprehensive examination, and relates not only to uranium extraction but to safe extraction of dumps from tailings as well.

Introduction. Physicochemical aspects of uranium concentrates obtaining from the wastes and raw materials

International Nuclear Information System (INIS)

Mirsaidov, I.U.

2014-01-01

The uranium deposits of Tajikistan played an immensely significant role in the practical solution of a radioactive raw materials problem which appeared during the post-World War II years in the USSR. The pioneer in this field became complex №6 (currently known as 'Vostokredmet'). The first soviet uranium was produced from the ores extracted from the republic's deposits. For 50 years (1945-1995 y.), uranium bearing raw materials from all over the former USSR were delivered to Tajikistan, and uranium oxide was produced, which was later delivered back to Russia for further production of enriched uranium. The total volume of uranium produced in Tajikistan plants was approximately 100 thousands tons. In Sughd region, during that period, more than 55 million tons of uranium waste was accumulated. The total activity of the waste, according to different calculations, is approximately 240-285 TBq. The total amount of waste in dumps and tailings piles is estimated to be more than 170 million tons, most of which are located in the neighborhoods of hydrometallurgical plants and heap leaching locations. Uranium industry wastes in Northern Tajikistan have become attractive for different investors and commercial companies, from secondary reprocessing of mines and tailings' point of view, since the uranium price is increasing. In this regard, research on developing uranium extraction methods from wastes is broadening. The study of the possibility and economic reasonability of reprocessing former year's dumps requires comprehensive examination, and relates not only to uranium extraction but to safe extraction of dumps from tailings as well.

Uranium 2014: Resources, Production and Demand

International Nuclear Information System (INIS)

Vance, Robert

2014-01-01

Since the mid-1960's, with the co-operation of their member countries and states, the OECD Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA) have jointly prepared periodic updates (currently every two years) on world uranium resources, production and demand. Published by the OECD/NEA in what is commonly known as the 'Red Book', the 25. edition, released in September 2014, contains 45 national reports covering uranium producing and consuming countries and those with plans to do so. The uranium resource figures presented in the 25. edition of the Red Book are a snapshot of the situation as of 1 January 2013. Resource figures are dynamic and related to commodity prices. Despite less favourable market conditions, continued high levels of investment and associated exploration efforts have resulted in the identification of additional resources of economic interest, just as in past periods of intense exploration activity. Total identified resources (reasonably assured and inferred) as of 1 January 2013 amounted to 5 902 900 tonnes of uranium metal (tU) in the 3 O 8 ) category, an increase of 10.8% compared to 1 January 2011. In the highest cost category ( 3 O 8 ) which was reintroduced in 2009, total identified resources amounted to 7 635 200 tU, an increase of 7.6% compared to the total reported in 2011. The majority of the increases are a result of re-evaluations of previously identified resources and additions to known deposits, particularly in Australia, Canada, the People's Republic of China, the Czech Republic, Greenland, Kazakhstan and South Africa. Worldwide exploration and mine development expenditures in 2012 totalled USD 1.92 billion, a 21% increase over updated 2010 figures, despite declining market prices. Production in 2012 increased by 7.4% from 2011 to 58 816 tU and is expected to increase to over 59 500 tU in 2013. This recent growth is principally the result of increased production in Kazakhstan, which remains the world

Radiological analyses of solids in the area of the old uranium mine of Rosglas (Morbihan)

International Nuclear Information System (INIS)

2008-07-01

After a brief presentation of the different uranium sites previously exploited in Brittany, this document reports measurements performed on one of them, the old uranium mine of Rosglas. In situ radiation measurements and sampling (surface soil, rocks, and sediments) were performed. Samples were then analysed (gamma radiation measurements) in order to asses the contamination by Uranium 238 and 235. The authors outline that some radioactive wastes are still accessible and therefore expose public to health risks. They discuss how to take these risks into account and discuss the required restructuring works to be done

Solvent extraction of uranium from high acid leach solution

International Nuclear Information System (INIS)

Ramadevi, G.; Sreenivas, T.; Navale, A.S.; Padmanabhan, N.P.H.

2010-01-01

A significant part of the total uranium reserves all over the world is contributed by refractory uranium minerals. The refractory oxides are highly stable and inert to attack by most of the commonly used acids under normal conditions of acid strength, pressure and temperature. Quantitative dissolution of uranium from such ores containing refractory uranium minerals requires drastic operating conditions during chemical leaching like high acid strength, elevated pressures and temperatures. The leach liquors produced under these conditions normally have high free acidity, which affects the downstream operations like ion exchange and solvent extraction

Health and environmental impact of depleted uranium

International Nuclear Information System (INIS)

Furitsu, Katsumi

2010-01-01

Depleted Uranium (DU) is 'nuclear waste' produced from the enrichment process and is mostly made up of 238 U and is depleted in the fissionable isotope 235 U compared to natural uranium (NU). Depleted uranium has about 60% of the radioactivity of natural uranium. Depleted uranium and natural uranium are identical in terms of the chemical toxicity. Uranium's high density gives depleted uranium shells increased range and penetrative power. This density, combined with uranium's pyrophoric nature, results in a high-energy kinetic weapon that can punch and burn through armour plating. Striking a hard target, depleted uranium munitions create extremely high temperatures. The uranium immediately burns and vaporizes into an aerosol, which is easily diffused in the environment. People can inhale the micro-particles of uranium oxide in an aerosol and absorb them mainly from lung. Depleted uranium has both aspects of radiological toxicity and chemical toxicity. The possible synergistic effect of both kinds of toxicities is also pointed out. Animal and cellular studies have been reported the carcinogenic, neurotoxic, immuno-toxic and some other effects of depleted uranium including the damage on reproductive system and foetus. In addition, the health effects of micro/ nano-particles, similar in size of depleted uranium aerosols produced by uranium weapons, have been reported. Aerosolized DU dust can easily spread over the battlefield spreading over civilian areas, sometimes even crossing international borders. Therefore, not only the military personnel but also the civilians can be exposed. The contamination continues after the cessation of hostilities. Taking these aspects into account, DU weapon is illegal under international humanitarian laws and is considered as one of the inhumane weapons of 'indiscriminate destruction'. The international society is now discussing the prohibition of DU weapons based on 'precautionary principle'. The 1991 Gulf War is reportedly the first

Influence of radon-daughter exposure rate and uranium ore dust concentration on occurrence of lung tumors

International Nuclear Information System (INIS)

Cross, F.T.; Palmer, R.F.; Busch, R.H.

1980-01-01

Groups of male SPF Wistar rats were exposed concurrently to several levels of radon daughters and uranium ore dust to study the effect of these variables on pulmonary disease states. Clinical pathology data at 1 yr postexposure indicate no significant differences among exposed animals when compared with controls. Preliminary histopathologic data suggest a trend toward increasing lung tumor risk as the exposure rate is decreased (constant total dose), but the differences are not statistically significant at the 0.05 level. A similar trend occurs with decrease in ore dust concentration (except for the 2560-WLM exposure group), but these differences are also not significant at the 0.05 level. The tumor risk is significantly (0.05 level) increased as the exposure level increases from approximately 320 and 640 WLM to 2560 WLM at the high ore dust concentration

Investigation of the binding of tiron to uranium(IV) and uranium(VI) found in soil

International Nuclear Information System (INIS)

Birnbaum, E.R.; Iams, H.D.; del Rio Garcia, M.; Ford, D.K.; Smith, P.H.; Strietelmeier, B.; Brainard, J.

1993-01-01

The authors are investigating the utility of a chelate-reductant system to extract uranium from 2 million yards of contaminated soil at the Fernald uranium reprocessing plant near Cincinnati, Ohio. It has been found that reduction of the uranyl contaminants using Tiron as the ligand. Of concern is whether the increased mobilization is simply a result of the higher affinity of Tiron to U(IV), or whether reduction of amorphous iron oxides contained in the soil is exposing greater amounts of uranyl ions to the ligand. It is important to establish if the latter mechanism is occurring, since a removal process which does not damage the soil is desired. Potentiometric and spectrophotometric studies of Tiron binding to soluble uranyl and U(V) salts will be presented as models to help understand the soil studies. Extraction behavior of UO 2 (OH) 2 will also be presented

Uranium hydrogeochemical and stream sediment reconnaissance of the Durango NTMS quadrangle, Colorado

International Nuclear Information System (INIS)

Dawson, H.E.; Weaver, T.A.

1979-01-01

During the spring and summer of 1976, 1518 water and 1604 waterborne sediment samples were collected from 1804 locations in the Durango NTMS quadrangle, Colorado. The samples obtained from this 19 940-km 2 area were analyzed at the Los Alamos Scientific Laboratory for total uranium. The uranium concentrations in waters ranged from less than the detectable limit of 0.2 ppB to 25.7 ppB, with a mean value of 0.84 ppB. The concentrations in sediments ranged from 1.0 ppM to 71.6 ppM, with a mean value of 4.2 ppM. Study of total water and total sediment populations indicated that both are actually mixtures of several populations. Consequently, samples were chosen for discussion on the basis of their having conspicuously high uranium concentrations relative to surrounding background values. Thirty-four water samples (approximately 2.2% of the total water population) had uranium concentrations above 5.00 ppB, the highest of which were well water samples from the San Luis Valley. Thirty-seven sediment samples (approximately 2.3% of the total sediment population) had uranium concentrations above 12.0 ppM. The majority of these were taken from sites in Precambrian rocks, but several came from Paleozoic and Mesozoic strate and Tertiary volcanics. The uranium concentrations in sediment samples from areas of Precambrian rock were especially high and these areas may warrant further, more detailed investigations

International Uranium Resources Evaluation Project (IUREP) national favourability studies: India

International Nuclear Information System (INIS)

1977-08-01

Physiographically India has a total area of 3,268,010 km 2 in three distinct regions. 1. The Peninsular shield in the south with an area of 823,310 km 2 . 2. The Himalayan mountain system with an area of 1,797,200 km 2 . 3. The Indo-Gangetic alluvial plain with an area of 647,500 km 2 . The three presently recognised major uranium provinces in India are: 1. The Singhbhum uranium province; 2. The Rajasthan uranium province, 3. The Madhya Pradesh uranium province. The Atomic Minerals Division of the Department of Atomic Energy has carried out a vigorous exploration programme since 1949 but despite their efforts a great deal of ground has still to be explored. At present, structurally controlled deposits account for most of the uranium resources of India. Uranium occurrences and deposits have been outlined in (1) Vein type deposits (the Singhbhum belt), (2) Conglomerate (Karnataka and Udaipur area, Raiasthan), (3) Sandstones (Madhra Pradesh and Swaliks, Himachal Pradesh, (4) Others such as carbonatites, marine phosphates, etc, (Mussorrie - Sahasradhara In Uttar Pradesh and Chatterpur-Saucur in Madhya Pradesh), (5) By-product Uranium in copper tailings and beach sands. India's total resources are listed as 52,538 tonnes uranium (68,300 short tons U 3 O 8 ) with additional resources from monazite of 12700 tonnes uranium. In view of the wide geological favourability, the many types of occurrences already known and the vast areas of unexplored ground it is estimated that the Speculative Potential may be between 150,000 and 250,000 tonnes uranium which is Category 5. (author)

Determining uranium speciation in contaminated soils by molecular spectroscopic methods: Examples from the Uranium in Soils Integrated Demonstration

International Nuclear Information System (INIS)

Allen, P.G.; Berg, J.M.; Chisholm-Brause, C.J.; Conradson, S.D.; Donohoe, R.J.; Morris, D.E.; Musgrave, J.A.; Tait, C.D.

1994-01-01

The US Department of Energy's former uranium production facility located at Fernald, OH (18 mi NW of Cincinnati) is the host site for an Integrated Demonstration for remediation of uranium-contaminated soils. A wide variety of source terms for uranium contamination have been identified reflecting the diversity of operations at the facility. Most of the uranium contamination is contained in the top ∼1/2 m of soil, but uranium has been found in perched waters indicating substantial migration. In support of the development of remediation technologies and risk assessment, we are conducting uranium speciation studies on untreated and treated soils using molecular spectroscopies. Untreated soils from five discrete sites have been analyzed. We have found that ∼80--90% of the uranium exists as hexavalent UO 2 2+ species even though many source terms consisted of tetravalent uranium species such as UO 2 . Much of the uranium exists as microcrystalline precipitates (secondary minerals). There is also clear evidence for variations in uranium species from the microscopic to the macroscopic scale. However, similarities in speciation at sites having different source terms suggest that soil and groundwater chemistry may be as important as source term in defining the uranium speciation in these soils. Characterization of treated soils has focused on materials from two sites that have undergone leaching using conventional extractants (e.g., carbonate, citrate) or novel chelators such as Tiron. Redox reagents have also been used to facilitate the leaching process. Three different classes of treated soils have been identified based on the speciation of uranium remaining in the soils. In general, the effective treatments decrease the total uranium while increasing the ratio of U(IV) to U(VI) species

Estimation of uranium GI absorption fractions for children and adults

International Nuclear Information System (INIS)

Chen, J.; Lariviere, D.; Timmins, R.; Verdecchia, K.

2011-01-01

Uranium is ubiquitously found in drinking water and food. The gastrointestinal tract absorption fraction (f 1 ) is an important parameter in risk assessment of uranium burdens from ingestion. Although absorption of uranium from ingestion has been studied extensively in the past, human data concerning children and adults are still limited. In a previous study based on measurements of uranium concentration in 73 bone-ash samples collected by Health Canada, the absorption fractions for uranium ingestion were determined to be 0.093 ± 0.113 for infants, and 0.050 ± 0.032 for young children ranging from 1 to 7 y of age. To extend the study, a total of 69 bone-ash samples were selected for children and adults ranging from 7 to 25 y of age and residing in the same Canadian community that is known to have an elevated level of uranium in its drinking water supply. For each bone-ash sample, the total uranium concentration was measured by inductively coupled plasma mass spectrometry. To solve uranium transfer in the biokinetic model for uranium given in International Commission of Radiological Protection (ICRP) Publication 69 with estimated daily uranium intake, the program WinSAAM v3.0.1 was used. The absorption fractions were determined to be 0.030 ± 0.022 for children (7-18 y) and 0.021 ± 0.015 for adults (18-25 y). For anyone more than 18 y of age, the estimated f 1 value for uranium agree well with the ICRP recommended value of 0.02. Published by Oxford Univ. Press on behalf of the Canadian Government 2010. (authors)

Certification of a uranium dioxide reference material for chemical analyses

International Nuclear Information System (INIS)

Le Duigou, Y.

1984-01-01

This report, issued by the Central Bureau for Nuclear Measurements (CBNM), describes the characterization of a uranium dioxide reference material with accurately determined uranium mass fraction for chemical analyses. The preparation, conditioning, homogeneity tests and the analyses performed on this material are described in Annex 1. The evaluation of the individual impurity results, total of impurities and uranium mass fraction are given in Annex 2. Information on a direct determination of uranium by titration is given in Annex 3. The uranium mass fraction (881.34+-0.13) g.kg -1 calculated in Annex 2 is given on the certificate

TERNARY ALLOYS OF URANIUM, COLUMBIUM, AND ZIRCONIUM

Science.gov (United States)

Foote, F.G.

1960-08-01

Ternary alloys of uranium are described which are useful as neutron- reflecting materials in a fast neutron reactor. They are especially resistant to corrosion caused by oxidative processes of gascous or aqueous origin and comprise uranium as the predominant metal with zirconiunn and niobium wherein the total content of the minor alloying elements is between 2 and 8% by weight.

Possible uranium sources of Streltsovsky uranium ore field

International Nuclear Information System (INIS)

Zhang Lisheng

2005-01-01

The uranium deposit of the Late Jurassic Streltsovaky caldera in Transbaikalia of Russia is the largest uranium field associated with volcanics in the world, its uranium reserves are 280 000 t U, and it is the largest uranium resources in Russia. About one third of the caldera stratigraphic pile consists of strongly-altered rhyolites. Uranium resources of the Streltsovsky caldera are much larger than any other volcanic-related uranium districts in the world. Besides, the efficiency of hydrothermal alteration, uranium resources appear to result from the juxtaposition of two major uranium sources; highly fractionated peralkaline rhyolites of Jurassic age in the caldera, and U-rich subalkaline granites of Variscan age in the basement in which the major uranium-bearing accessory minerals were metamict at the time of the hydrothermal ore formation. (authors)

Process for continuous production of metallic uranium and uranium alloys

Science.gov (United States)

Hayden, Jr., Howard W.; Horton, James A.; Elliott, Guy R. B.

1995-01-01

A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO.sub.3), or any other substantially stable uranium oxide, to form the uranium dioxide (UO.sub.2). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl.sub.4), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation.

Process for continuous production of metallic uranium and uranium alloys

Science.gov (United States)

Hayden, H.W. Jr.; Horton, J.A.; Elliott, G.R.B.

1995-06-06

A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO{sub 3}), or any other substantially stable uranium oxide, to form the uranium dioxide (UO{sub 2}). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl{sub 4}), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation. 4 figs.

VapC toxins drive cellular dormancy under uranium stress for the extreme thermoacidophile Metallosphaera prunae.

Science.gov (United States)

Mukherjee, Arpan; Wheaton, Garrett H; Counts, James A; Ijeomah, Brenda; Desai, Jigar; Kelly, Robert M

2017-07-01

When abruptly exposed to toxic levels of hexavalent uranium, the extremely thermoacidophilic archaeon Metallosphaera prunae, originally isolated from an abandoned uranium mine, ceased to grow, and concomitantly exhibited heightened levels of cytosolic ribonuclease activity that corresponded to substantial degradation of cellular RNA. The M. prunae transcriptome during 'uranium-shock' implicated VapC toxins as possible causative agents of the observed RNA degradation. Identifiable VapC toxins and PIN-domain proteins encoded in the M. prunae genome were produced and characterized, three of which (VapC4, VapC7, VapC8) substantially degraded M. prunae rRNA in vitro. RNA cleavage specificity for these VapCs mapped to motifs within M. prunae rRNA. Furthermore, based on frequency of cleavage sequences, putative target mRNAs for these VapCs were identified; these were closely associated with translation, transcription, and replication. It is interesting to note that Metallosphaera sedula, a member of the same genus and which has a nearly identical genome sequence but not isolated from a uranium-rich biotope, showed no evidence of dormancy when exposed to this metal. M. prunae utilizes VapC toxins for post-transcriptional regulation under uranium stress to enter a cellular dormant state, thereby providing an adaptive response to what would otherwise be a deleterious environmental perturbation. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

Balance of the uranium market. Contribution to an economic analysis. Vol. 1

International Nuclear Information System (INIS)

Ehsani, J.

1983-11-01

The evolution of the economic and the energetic world situation for these last 40 years are first described stressing electricity production. Place of nuclear energy in the energy market is analyzed taking into account socio-political factors. In a second part, cost for electricity production from different sources: coal, nuclear power, fuel-oil are compared. Two models for uranium world supply and demand are developed. In the third part the uranium market balance, is examined. The analysis includes 3 steps: determination of total uranium demand from 1983 to 2000, determination of total uranium supply by portion of production cost, supply and demand are compared for future evolution with different hypothesis [fr

Recovery of uranium from sea water - a laboratory study

International Nuclear Information System (INIS)

Jayawant, D.V.; Iyer, N.S.; Koppiker, K.S.

1991-01-01

Sea water contains traces of uranium, but the volume of sea water being enormous, the total quantity of uranium available from the sources is very large. From time to time, claims have been made elsewhere that a breakthrough has been made in developing a technology to recovery this uranium at an economic cost. Studies have been carried out at Uranium Extraction Division over a few years to develop a suitable technique to separate the uranium from sea water. Studies were primarily directed towards preparation of suitable inorganic ion exchangers and studying their properties. In this paper preparation of ion exchangers based on hydrous titanium oxide and the data collected in laboratory trials on their application for uranium adsorption from sea water are presented. (author). 11 refs., 2 tabs

Uranium. Resources, production, and market - 2009 Red Book

International Nuclear Information System (INIS)

Anon.

2010-01-01

The ''Red Book'' has been compiled since the mid-1960s as a joint OECD/NEA and IAEA publication. The analysis presents an overview of present uranium supply and demand with perspectives reaching as far as 2035. Data from 35 countries were accumulated about exploration, resources, production, and prices. The 23 rd edition contains the most recent basic evaluations of the world uranium market, providing a profile of nuclear fuel supply. Forecasts of nuclear generating capacity and uranium requirement for reactor use up until 2035 are presented along with a discussion of uranium supplies and aspects of demand beyond that time frame. Worldwide expenditures for the exploration of uranium resources in 2008 totaled more than US $1.6 billion, which is a 133% increase over expenses in 2006. Most of the important producer countries reported rising expenses for exploration as well as for commissioning new production centers. The total ''identified'' (=reasonably assured and inferred) reserves as of January 1, 2009 in the 3 O 8 ) category decreased slightly to 5,404,000 t U while a clear increase to 6,306,300 t U was seen in the re-introduced ''high cost'' category ( 3 O 8 ). Uranium production in 2008 amounted to 43,880 t U, which is an increase of 6% over 2007 (41,244 t U), and of 11% over 2006 (39,617 t U). In 2008, worldwide uranium production (43,880 t U) covered roughly 74% of the worldwide requirement for use in reactors (59,065 t U). The balance was met out of secondary sources. (orig.)

78 FR 72123 - Request To Amend a License to Export High-Enriched Uranium

Science.gov (United States)

2013-12-02

... NUCLEAR REGULATORY COMMISSION Request To Amend a License to Export High-Enriched Uranium Pursuant... manufacture HEU targets in Belgium. National Nuclear Security Uranium (HEU) uranium France for irradiation in... 5.8 kg of U- 235 contained in 6.2 kg uranium to a new cumulative total of 12.615 kg of U-235...

The light water natural uranium reactor

International Nuclear Information System (INIS)

Radkowsky, A.

A new type of light water seed blanket with the seed having 20% enrichment and the blanket a special combination of elements of natural uranium and thorium, relatively close packed, but sufficient spacing for heat transfer purpose is described. The blanket would deliver approximately half the total energy for about 10,000 MWDIT, so this type of core would be just as economical or better in uranium ore consumation as present cores. (author)

Experimental measurement of fission fragments paths in uranium gold, molybdenum, zirconium and silicon; Mesure experimentale des parcours des fragments de fission dans l'uranium, l'or, le molybdene, le zirconium et le silicium

Energy Technology Data Exchange (ETDEWEB)

Faraggi, H; Garin-Bonnet, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

The measurement of total number of fissiongments emerging from an homogeneous, thick alloy composed of uranium plus another element (the concentration of uranium being known) allows to obtain the range of the fragments in this alloy. By varying the concentration, the range of the fragments in uranium and in the other element can be deduced. (author)Fren. [French] La mesure du nombre total de fragments de fission sortant d'un alliage homogene epais d'uranium et d'un autre element, pour lequel la concentration en uranium est donnee, permet la mesure du parcours des fragments dans cet alliage. En faisant varier la concentration, on peut deduire de ces mesures le parcours des fragments dans l'uranium et dans l'autre element. (auteur)

The relationship between uranium in blood and the number of working years in the Syrian phosphate mines

International Nuclear Information System (INIS)

Othman, I.

1993-01-01

Since phosphate contains uranium, workers in phosphate mines may be expected to be exposed to radioactive elements from this source. Uranium is concentrated in three main areas in the body: bone, liver and kidney. The author chose three carriers of uranium, blood, urine and hair to study the relationship between uranium concentration and the number of working years spent in the mine. Uranium was measured in samples from workers and their families by fluorimetry. The quenching effect of blood, urine and heir on uranium standards was determined. The results show that uranium concentrations (in blood) increase with the number of working year in the mine. In addition, it has also been determined that uranium concentrations in blood samples of families living near the mine are higher than those in families living in Damascus city. Finally, it has been found that hair is not a good biological indicator for this type of study. (author). 13 refs., 4 tabs., 3 figs

78 FR 60928 - Request To Amend a License To Export High-Enriched Uranium

Science.gov (United States)

2013-10-02

... NUCLEAR REGULATORY COMMISSION Request To Amend a License To Export High-Enriched Uranium Pursuant... manufacture HEU The Netherlands. National Nuclear Security Uranium uranium (17.1 targets in France... export from 9.4 kg of U-235 contained in 10.1 kg uranium to a new cumulative total of 17.1 kg of U-235...

Ore-forming environment identification and uranium metallogenic features in Manite depression

International Nuclear Information System (INIS)

Liu Zhengyi; Liu Wusheng; Jia Licheng; Shi Qingping; Peng Cong; Chen Hua

2014-01-01

By using limonitization, the important indicator of uranium ore-forming identification as the product of acid water transportation from the reducing environment to the oxidation environment, based on the specimen examination naked eye, microscopic identification, electron microscopy, electron microprobe were used to study the major elements, trace elements, organic carbon, total sulfur, uranium valence and uranium, thorium isotope "2"3"4U/"2"3"8U, "2"3"0Th/"2"3"2Th ratio, hydrocarbons especially clay mineral species and the total amount, V/(V + Ni) water stratification and bottom hydrodynamic environment and other factors, which can indicate the microphase environment of all types of rocks in Manite depression, and uranium ore-forming factors were identified and evaluation are discussed and some suggestions were submitted. (authors)

Evaluation of parameters associated with monitoring in vivo of uranium isotopes in the lungs

International Nuclear Information System (INIS)

Juppa, Silvia P.; Lucena, Eder A.; Dantas, Bernardo M.; Dantas, Ana Leticia A.

2013-01-01

The objective of this study is to evaluate the parameters associated with the technique of monitoring individuals exposed to uranium isotopes, aiming to optimize the technique and reduced uncertainties associated

Temporal variation of uranium in ground water with conductivity

International Nuclear Information System (INIS)

Pulhani, Vandana; Chaudhury, Moushumi D.; Jha, S.K.; Tripathi, R.M.

2015-01-01

The concentration of uranium in drinking water sources is a matter of health concern since it has been proved to be chemo-toxic to humans. Uranium being a more soluble actinide is also very mobile in the environment. The effect of water quality parameters and their co-relation to uranium content in the water is an interesting study to understand and predict its behavior in ground water and subsequently to judge the hazard posed. Hence studies on spatial and temporal variation of uranium concentration with electrical conductivity, pH, total dissolved solids and salinity in ground water was carried out. (author)

Determination of uranium distribution in the evaporation of simulated Savannah River Site waste

International Nuclear Information System (INIS)

Barnes, M.J.; Chandler, G.T.

1995-01-01

The results of an experimental program addressing the distribution of uranium in saltcake and supernate for two Savannah River Site waste compositions are presented. Successive batch evaporations were performed on simulated H-Area Modified Purex low-heat and post-aluminum dissolution wastes spiked with depleted uranium. Waste compositions and physical data were obtained for supernate and saltcake samples. For the H-Area Modified Purex low-heat waste, the product saltcake contained 42% of the total uranium from the original evaporator feed solution. However, precipitated solids only accounted for 10% of the original uranium mass; the interstitial liquid within the saltcake matrix contained the remainder of the uranium. In the case of the simulated post-aluminum dissolution waste; the product saltcake contained 68% of the total uranium from the original evaporator feed solution. Precipitated solids accounted for 52% of the original uranium mass; again, the interstitial liquid within the saltcake matrix contained the remainder of the uranium. An understanding of the distribution of uranium between supernatant liquid, saltcake, and sludge is required to develop a material balance for waste processing operations. This information is necessary to address nuclear criticality safety concerns

Inhibition of poly(ADP-ribose)polymerase-1 and DNA repair by uranium

Energy Technology Data Exchange (ETDEWEB)

Cooper, Karen L.; Dashner, Erica J. [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Tsosie, Ranalda [Department of Chemistry and Biochemistry, University of Montana, Missoula, MT 59812 (United States); Cho, Young Mi [Department of Food and Nutrition, College of Human Ecology, Hanyang University, Seoul 133-791 (Korea, Republic of); Lewis, Johnnye [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Community Environmental Health Program, University of New Mexico Health Sciences Center College of Pharmacy, Albuquerque, NM 87131 (United States); Hudson, Laurie G., E-mail: lhudson@salud.unm.edu [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States)

2016-01-15

Uranium has radiological and non-radiological effects within biological systems and there is increasing evidence for genotoxic and carcinogenic properties attributable to uranium through its heavy metal properties. In this study, we report that low concentrations of uranium (as uranyl acetate; < 10 μM) is not cytotoxic to human embryonic kidney cells or normal human keratinocytes; however, uranium exacerbates DNA damage and cytotoxicity induced by hydrogen peroxide, suggesting that uranium may inhibit DNA repair processes. Concentrations of uranyl acetate in the low micromolar range inhibited the zinc finger DNA repair protein poly(ADP-ribose) polymerase (PARP)-1 and caused zinc loss from PARP-1 protein. Uranyl acetate exposure also led to zinc loss from the zinc finger DNA repair proteins Xeroderma Pigmentosum, Complementation Group A (XPA) and aprataxin (APTX). In keeping with the observed inhibition of zinc finger function of DNA repair proteins, exposure to uranyl acetate enhanced retention of induced DNA damage. Co-incubation of uranyl acetate with zinc largely overcame the impact of uranium on PARP-1 activity and DNA damage. These findings present evidence that low concentrations of uranium can inhibit DNA repair through disruption of zinc finger domains of specific target DNA repair proteins. This may provide a mechanistic basis to account for the published observations that uranium exposure is associated with DNA repair deficiency in exposed human populations. - Highlights: • Low micromolar concentration of uranium inhibits polymerase-1 (PARP-1) activity. • Uranium causes zinc loss from multiple DNA repair proteins. • Uranium enhances retention of DNA damage caused by ultraviolet radiation. • Zinc reverses the effects of uranium on PARP activity and DNA damage repair.

Contribution to uranium geochemistry in intrusive granites; Contribution a la geochimie de l'uranium dans les granites intrusifs

Energy Technology Data Exchange (ETDEWEB)

Coulomb, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1959-01-15

This work aims to define the position of a certain number of French granitic deposits within the field of the geochemistry of granites in general, and of the geochemistry of uranium in particular. The regions concerned are: - 3 French Hercynian ranges, in the Vendee, in Brittany and in the Morvan, - 1 African range, probably precambrian, of the Hoggar. For each range, the petrochemical framework is first of all determined and then the degree of chemical homogeneity of the rocks is evaluated. In the petrochemical groups thus obtained the geochemical behaviour of the uranium is studied. From a point of view of the geochemistry of the granites under investigation, a comparison of the laws of distribution of the major elements in the 4 ranges shows up a convergence of average composition which was not anticipated by geological and petrographic considerations alone. The statistical and geochemical distribution laws of the total uranium as a function of the petrochemical variations are established. A study of the chemical forms of uranium in the rocks has drawn an attention to the qualitative and quantitative importance of the fraction of this uranium soluble in dilute acids. We have therefore reconsidered on the one hand, the laws of distribution of the insoluble uranium, which represents essentially the uranium fixed in crystalline structures (zircon, allanite...), and we have justified on the other hand the interest presented by the soluble uranium: this, although more complex in character, presents a geochemical unity in post magmatic phenomena which makes possible to find a genetic connection between the uraniferous deposits and the intrusive massifs. Finally we have given a plan of the geochemical cycle of uranium, in which we hope to have provided some more accurate data on the igneous phase. (author) [French] Le but du travail presente est de situer sur le plan de la geochimie des granites en general, sur le plan de la geochimie de l'uranium en particulier, un

Health and environmental effects of depleted uranium

International Nuclear Information System (INIS)

Millar, W.A.

2001-01-01

Knowledge accumulated till the end of the 20th century is mentioned briefly. More attention is paid to recent findings. Recent studies of uranium contamination of the Persian Gulf and Balkan War veterans have been conducted in the U.S. and Canada by studying distribution of isotopes of DU in the veterans of the NATO and Allied forces who were accidentally contaminated with DU either in the form of imbedded shrapnel or inhalation of uranium contaminating dust. The studies of the U.S. armed forces Research Institute in Bethesda Maryland on the shrapnel wounded veteran's demonstrated increased concentration of the isotopes of DU in the urine eight years after the Persian Gulf War. In contrast non-governmental uranium research groups such as Uranium Medical Centre reported increased urinary excretion of four isotopes of DU in the Allied forces veterans exposed to DU containing dust ten years after the exposure. These studies were confirmed by two methods. Neutron activation analysis confirmed presence of DU in the urine of seven Persian Gulf veterans with ratios significantly different from the natural uranium and in the range of DU, ten years after exposure from inhalation. The veterans of the Allied forces contaminated by inhalation in the Persian Gulf War were also analyzed for the uranium presence for their body fluids, tissues and urine by the method of mass spectrometry. These results presented at the International Conferences in Dublin Ireland, Paris France and New York U.S.A. indicate significant presence of four uranium isotopes in over 60% of contaminated veterans being in the range of DU. The ratio of the uranium isotopes 235/238 is in the range of DU if higher than 137.8. It was found to be in the DU ratio 62% examined by the mass spectrometry analysis. Isotopic composition of natural enriched and DU should be for U 238 /99.3, U 235 /0.7 and U 234 /0.006 and for enriched uranium 99.01, 2.96 and 0.03, while for DU respective ratios are 99.75, 0.25 and 0

Unraveling uranium induced oxidative stress related responses in Arabidopsis thaliana seedlings. Part II: responses in the leaves and general conclusions.

Science.gov (United States)

Vanhoudt, Nathalie; Cuypers, Ann; Horemans, Nele; Remans, Tony; Opdenakker, Kelly; Smeets, Karen; Bello, Daniel Martinez; Havaux, Michel; Wannijn, Jean; Van Hees, May; Vangronsveld, Jaco; Vandenhove, Hildegarde

2011-06-01

The cellular redox balance seems an important modulator under heavy metal stress. While for other heavy metals these processes are well studied, oxidative stress related responses are also known to be triggered under uranium stress but information remains limited. This study aimed to further unravel the mechanisms by which plants respond to uranium stress. Seventeen-day-old Arabidopsis thaliana seedlings, grown on a modified Hoagland solution under controlled conditions, were exposed to 0, 0.1, 1, 10 and 100 μM uranium for 1, 3 and 7 days. While in Part I of this study oxidative stress related responses in the roots were discussed, this second Part II discusses oxidative stress related responses in the leaves and general conclusions drawn from the results of the roots and the leaves will be presented. As several responses were already visible following 1 day exposure, when uranium concentrations in the leaves were negligible, a root-to-shoot signaling system was suggested in which plastids could be important sensing sites. While lipid peroxidation, based on the amount of thiobarbituric acid reactive compounds, was observed after exposure to 100 μM uranium, affecting membrane structure and function, a transient concentration dependent response pattern was visible for lipoxygenase initiated lipid peroxidation. This transient character of uranium stress responses in leaves was emphasized by results of lipoxygenase (LOX2) and antioxidative enzyme transcript levels, enzyme capacities and glutathione concentrations both in time as with concentration. The ascorbate redox balance seemed an important modulator of uranium stress responses in the leaves as in addition to the previous transient responses, the total ascorbate concentration and ascorbate/dehydroascorbate redox balance increased in a concentration and time dependent manner. This could represent either a slow transient response or a stable increase with regard to plant acclimation to uranium stress. Copyright �

Preliminary analysis of accidents on the Santa QuitÉria Project: occupationally exposed individuals

Energy Technology Data Exchange (ETDEWEB)

Anjos, Gullit Diego C. dos, E-mail: gullitcardoso@inb.gov.br [Indústrias Nucleares do Brasil (INB), Rio de Janeiro, RJ (Brazil)

2017-07-01

The Santa Quitéria Project (PSQ) is an enterprise that aims at the production of phosphate compounds as main products, and of uranium concentrates as by-products from minerals of the Itataia deposit. The intended area for implementation of the project is located in the municipality of Santa Quitéria, north central region of the State of Ceará. The U.S. Nuclear Regulatory Commission lists the basic design accidents for a Uranium Processing Plant, such as the PSQ. Among all these scenarios, fire in uranium extraction cells was the one with the highest doses released. For simulation of the fire event, the atmospheric dispersion model used was the standard Gaussian plume model. The doses were calculated for two sets of meteorological conditions: stability class F, with wind velocity of 1 m/s and class D stability with wind velocity of 4.5 m/s. For PSQ, it was considered that there will be no public individual until after 2000 meters from the release point. The doses corresponding to the occupationally exposed individuals are: 2.0E-3 mSv (class D) and 5 mSv (Class F), 300 meters away from the event. Analyzing the results, it can be concluded that there are no significant radiological consequences for the occupationally exposed individual, both in the stability class D and the F. The doses of the workers are well below the levels that could cause deterministic effects. Even if an occupationally exposed individual were exposed for 12 hours in the center of the plume, the dose received would not exceed the annual limit established by CNEN. (author)

Uranium content in soil after bombing FRY

International Nuclear Information System (INIS)

Biocanin, B.; Cvijovic, M.; Golobocanin, D.; Markovic, M.; Miljevic, N.; Orlic, M; Todorovic, D.; Veselinovic, D.

2002-01-01

Depleted uranium (DU) is a byproduct of uranium enrichment process and its use is very dangerous and harmful. NATO has used DU ammunition in Yugoslav conflict during its air campaign against the tanks and bunkers. The estimated number of about 3,000-10,000 of 30 mm DU rounds as armor-piercing shells were fired from cannons fitted to A-10 aircraft and probably a usage in some of 1,500 launched Tomahawk Cruise missiles. We measured uranium content in the surface soil (0-5 cm depth) from bomb craters during NATO attack. Selected locations were Belgrade, Smederevo, Nis, Bor, Prahovo, Kadinjaca, Jadovnik, Raska, Sjenica, and Cape Arza. Total uranium concentration and isotopic ratio were determined using γ-spectrometry and inductively coupled plasma method. Obtained results were in the range 21 - 762.000 Bq/kg dry soil. They were at the all locations except Cape Arza comparable to the uranium content found in off-side locations of soils. (author)

Recovery of uranium from Cu-flotation tails

International Nuclear Information System (INIS)

Jayaram, K.M.V.; Sankaran, R.N.; Dwivedy, K.K.

1984-01-01

Uranium occurs along with copper in several parts of India. Since the total contained uranium in some of these deposits is very large, detailed studies were carried out on samples of ore obtained from Surda, Mosabani and Rakha Cu-flotation tails analysing 0.014 per cent, 0.010 per cent and 0.011 per cent U 3 O 8 and 0.12 per cent 0.09 per cent and 0.11 per cent Cu respectively. Uranium in these samples occurs not only as free uraninite but is also associated with other minerals like apatite, magnetite, tourmaline and micas, formed at different stages of paragenitic sequence. The size also varies considerably. Because of this the recovery of uranium varied from 35 to 70 per cent by wet gravity separation of the feed. Since uranium has to be anyway extracted from these concentrates by hydrometallurgical processing, it is suggested that Cu-flotation tails may be treated by hydrometallurgy to increase the ultimate recovery. (author)

Uranium spectra in the ICP

Energy Technology Data Exchange (ETDEWEB)

Ghazi, A.A.; Qamar, S.; Atta, M.A. (Khan (A.Q.) Research Labs., Rawalpindi (Pakistan))

1994-05-01

Uranium spectra have been studied by inductively coupled plasma atomic emission spectroscopy (ICP-AES). In total, 8361 uranium lines were observed in the wavelength range of 235-500 nm. This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). The hard copy text is accompanied by a disk with data files and test files for an IBM-compatible computer. The main article discusses the scientific aspects of the subject and explains the purpose of the data files. (Author).

Uranium spectra in the ICP

International Nuclear Information System (INIS)

Ghazi, A.A.; Qamar, S.; Atta, M.A.

1994-01-01

Uranium spectra have been studied by inductively coupled plasma atomic emission spectroscopy (ICP-AES). In total, 8361 uranium lines were observed in the wavelength range of 235-500 nm. This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). The hard copy text is accompanied by a disk with data files and test files for an IBM-compatible computer. The main article discusses the scientific aspects of the subject and explains the purpose of the data files. (Author)

Ningyo Toge uranium enrichment pilot plant comes into full

International Nuclear Information System (INIS)

1982-01-01

The uranium enrichment pilot plant of the Power Reactor and Nuclear Fuel Development Corporation at Ningyo Toge went into full operation on March 26, 1982. This signifies that the front end of the nuclear fuel cycle in Japan, from uranium ore to enrichment, is only a step away from commercialization. On the same day, the pilot plant of uranium processing and conversion to UF 6 , the direct purification of uranium ore into uranium hexafluoride, began batch operation at the same works. The construction of the uranium enrichment pilot plant has been advanced in three stages: i.e. OP-1A with 1000 centrifuges, OP-1B with 3000 centrifuges and OP-2 with 3000 centrifuges. With a total of 7000 centrifuges, the pilot plant, the first enrichment plant in Japan, has now a capacity of supplying enriched uranium for six months operation of a 1,000 MW nuclear power plant. (J.P.N.)

Recovery of uranium from crude uranium tetrafluoride

Energy Technology Data Exchange (ETDEWEB)

Ghosh, S K; Bellary, M P; Keni, V S [Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

An innovative process has been developed for recovery of uranium from crude uranium tetrafluoride cake. The process is based on direct dissolution of uranium tetrafluoride in nitric acid in presence of aluminium hydroxide and use of solvent extraction for removal of fluorides and other bulk impurities to make uranium amenable for refining. It is a simple process requiring minimum process step and has advantage of lesser plant corrosion. This process can be applied for processing of uranium tetrafluoride generated from various sources like uranium by-product during thorium recovery from thorium concentrate, first stage product of uranium recovery from phosphoric acid by OPPA process and off grade uranium tetrafluoride material. The paper describes the details of the process developed and demonstrated on bench and pilot scale and its subsequent modification arising out of bulky solid waste generation. The modified process uses a lower quantity of aluminium hydroxide by allowing a lower dissolution of uranium per cycle and recycles the undissolved material to the next cycle, maintaining the overall recovery at high level. This innovation has reduced the solid waste generated by a factor of four at the cost of a slightly larger dissolution vessel and its increased corrosion rate. (author). 4 refs., 1 fig., 3 tabs.

Recovery of uranium from crude uranium tetrafluoride

International Nuclear Information System (INIS)

Ghosh, S.K.; Bellary, M.P.; Keni, V.S.

1994-01-01

An innovative process has been developed for recovery of uranium from crude uranium tetrafluoride cake. The process is based on direct dissolution of uranium tetrafluoride in nitric acid in presence of aluminium hydroxide and use of solvent extraction for removal of fluorides and other bulk impurities to make uranium amenable for refining. It is a simple process requiring minimum process step and has advantage of lesser plant corrosion. This process can be applied for processing of uranium tetrafluoride generated from various sources like uranium by-product during thorium recovery from thorium concentrate, first stage product of uranium recovery from phosphoric acid by OPPA process and off grade uranium tetrafluoride material. The paper describes the details of the process developed and demonstrated on bench and pilot scale and its subsequent modification arising out of bulky solid waste generation. The modified process uses a lower quantity of aluminium hydroxide by allowing a lower dissolution of uranium per cycle and recycles the undissolved material to the next cycle, maintaining the overall recovery at high level. This innovation has reduced the solid waste generated by a factor of four at the cost of a slightly larger dissolution vessel and its increased corrosion rate. (author)

The latest figures on uranium

International Nuclear Information System (INIS)

Vance, R.

2010-01-01

According to the latest figures on uranium, soon to be published by the NEA, uranium resources, production and demand are all on the rise. Exploration efforts have increased recently in line with the expected expansion of nuclear energy in the coming years. Total identified resources have grown and are now sufficient to cover 100 years of supply at 2008 rates of consumption. Costs of production have, however, also increased. This article is based on the latest edition of the 'Red Book', Uranium 2009: Resources, Production and Demand, which presents the results of the most recent biennial review of world uranium market fundamentals and a statistical profile of the world uranium industry as of 1 January 2009. It contains official data provided by OECD Nuclear Energy Agency (NEA) and International Atomic Energy Agency (IAEA) member countries on uranium exploration, resources, production and reactor-related requirements. Projections of nuclear generating capacity and reactor-related uranium requirements through 2035 are also provided as well as a discussion of long-term uranium supply and demand issues. Despite recent declines stemming from the global financial crisis, world demand for electricity is expected to continue to grow significantly over the next several decades to meet the needs of an increasing population and economic growth. The recognition by an increasing number of governments that nuclear power can produce competitively priced, base-load electricity that is essentially free of greenhouse gas emissions, coupled with the role that nuclear can play in enhancing security of energy supply, increases the prospects for growth in nuclear generating capacity, although the magnitude of that growth remains to be determined. Regardless of the role that nuclear energy ultimately plays in meeting rising electricity demand, the uranium resource base is more than adequate to meet projected requirements. Meeting even high-case requirements to 2035 would consume less

Natural uranium toxicology - evaluation of internal contamination in man; Toxicologie de l'uranium naturel - essai d'evaluation de la contamination interne chez l'homme

Energy Technology Data Exchange (ETDEWEB)

Chalabreysse, J. [Commissariat a l' Energie Atomique, Pierrelatte (France). Centre d' Etudes Nucleaires

1968-07-01

After reminding the physical and chemical properties of natural uranium which might affect its toxicology, a comprehensive investigation upon natural uranium metabolism and toxicity and after applying occupational exposure standards to this particular poison, it has been determined, from accident reports and human experience reported in the related literature, a series of formulae obtained by theoretical mathematical development giving principles for internal contamination monitoring and disclosure by determining uranium in the urine of occupationally exposed individuals. An assay is performed to determine individual internal contamination according to the various contamination cases. The outlined purposes, mainly practical, required some options and extrapolations. The proposed formula allows a preliminary approach and also to determine shortly a contamination extent or to discuss the systematical urinalysis results as compared with individual radio-toxicology monitoring professional standards. (author) [French] Apres le rappel des caracteristiques physiques et des proprietes chimiques de l'uranium naturel pouvant avoir une influence sur sa toxicologie, l'etude detaillee de son metabolisme et de sa toxicite, puis l'application des normes professionnelles d'exposition au cas particulier de ce toxique, il est etabli, a partir des comptes rendus d'accidents et de l'experimentation humaine rapportes dans la litterature, une serie de formules obtenues par developpement mathematique theorique qui posent les principes de la surveillance et de la mise en evidence de la contamination interne par la recherche et le dosage de l'uranium dans les urines d'individus professionnellement exposes. Un essai d'evaluation de la contamination interne individuelle suivant les differents cas de contamination est effectue. Le formulaire propose permet de faire une premiere approximation et d'apprecier rapidement l'importance d

Gastric cancer in New Mexico counties with significant deposits of uranium

International Nuclear Information System (INIS)

Wilkinson, G.S.

1985-01-01

Several counties in northern New Mexico display high rates of mortality from gastric cancer. Significant differences in sex-specific, age-adjusted, average annual stomach cancer mortality rates among whites from 1970-1979 were found between counties with significant deposits of uranium compared to those without significant deposits. These results remained unchanged when either socioeconomic status or Hispanic ethnicity were considered. Additional research needs to consider individual characteristics and competing risk factors for individuals with gastric cancer in these counties. A working hypothesis is that residents of counties with significant deposits of uranium are exposed to higher-than-average environmental levels of radionuclides such as radon and radon daughters, or to trace elements such as arsenic, cadmium, selenium, and lead which are commonly found in areas with uranium deposits

Uranium facilitated transport by water-dispersible colloids in field and soil columns

Energy Technology Data Exchange (ETDEWEB)

Crancon, P., E-mail: pierre.crancon@cea.fr [CEA, DAM, DIF, F-91297 Arpajon (France); Pili, E. [CEA, DAM, DIF, F-91297 Arpajon (France); Charlet, L. [Laboratoire de Geophysique Interne et Tectonophysique (LGIT-OSUG), University of Grenoble-I, UMR5559-CNRS-UJF, BP53, 38041 Grenoble cedex 9 (France)

2010-04-01

The transport of uranium through a sandy podzolic soil has been investigated in the field and in column experiments. Field monitoring, numerous years after surface contamination by depleted uranium deposits, revealed a 20 cm deep uranium migration in soil. Uranium retention in soil is controlled by the < 50 {mu}m mixed humic and clayey coatings in the first 40 cm i.e. in the E horizon. Column experiments of uranium transport under various conditions were run using isotopic spiking. After 100 pore volumes elution, 60% of the total input uranium is retained in the first 2 cm of the column. Retardation factor of uranium on E horizon material ranges from 1300 (column) to 3000 (batch). In parallel to this slow uranium migration, we experimentally observed a fast elution related to humic colloids of about 1-5% of the total-uranium input, transferred at the mean porewater velocity through the soil column. In order to understand the effect of rain events, ionic strength of the input solution was sharply changed. Humic colloids are retarded when ionic strength increases, while a major mobilization of humic colloids and colloid-borne uranium occurs as ionic strength decreases. Isotopic spiking shows that both {sup 238}U initially present in the soil column and {sup 233}U brought by input solution are desorbed. The mobilization process observed experimentally after a drop of ionic strength may account for a rapid uranium migration in the field after a rainfall event, and for the significant uranium concentrations found in deep soil horizons and in groundwater, 1 km downstream from the pollution source.

Depleted uranium in the environment - an issue of concern?

International Nuclear Information System (INIS)

Stegnar, P.; Benedik, Lj.

2002-01-01

Natural uranium (U) occurs in soils in typical concentrations of a few parts per milion. U-238 is the most abundant isotope in natural uranium (fraction by weight in natural uranium is 99.28%) and decays into other radioactive elements. A radioactive waste product of uranium enrichment is known as 'depleted uranium' (DU) which is basically natural uranium in which the fissionable U-235 isotopic content has been reduced from 0.71% to 0.2-0.3%. It is practically pure alpha emitter, only selected (in=growth) daughter products are gammaand beta emitters. Comparison of radioactivity shows that the total activity in 1mg of natural uranium is 25.28 Bq and in1 mg of DU is 14.80 Bq. The radioactivity of DU is 60% of that of natural uranium. Currently in the USA alone, there are about 600.000 tonnes of DU in storage. DU is cheap and it is available in large quantities. It is widely used as ballast or counterbalances in ships and aircrafts, as radiation shielding and in non-nuclear civil applications requiring hugh density material. (author)

Semi-automated potentiometric titration method for uranium characterization.

Science.gov (United States)

Cristiano, B F G; Delgado, J U; da Silva, J W S; de Barros, P D; de Araújo, R M S; Lopes, R T

2012-07-01

The manual version of the potentiometric titration method has been used for certification and characterization of uranium compounds. In order to reduce the analysis time and the influence of the analyst, a semi-automatic version of the method was developed in the Brazilian Nuclear Energy Commission. The method was applied with traceability assured by using a potassium dichromate primary standard. The combined standard uncertainty in determining the total concentration of uranium was around 0.01%, which is suitable for uranium characterization. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evaluation of uranium resources in Antarctica

International Nuclear Information System (INIS)

Zeller, E.J.; Dreschhoff, G.A.M.

1980-01-01

The continent of Antarctica comprises roughly nine per cent of the total land surface of the earth and is the only large land area that has been left almost totally unexplored for uranium resources. In 1976 the first systematic uranium resource evaluation, entitled Antarctica International Radiometric Survey, was started as a part of the US Antarctic Research Program. This project was staffed jointly by scientists from the University of Kansas and the Bundesanstalt fuer Geowissenschaften und Rohstoffe of the Federal Republic of Germany. The survey has continued for three antarctic field seasons and an extension of operations for the next four years has been approved. Two areas in the Transantarctic Mountains and one part of Marie Byrd Land have been surveyed by airborne gamma-ray spectrometric methods. The work that has been conducted demonstrates clearly that radiometric surveys can be performed successfully under the rigorous climatic conditions in Antarctica, and that significant and reproducible data can be obtained. So far no substantial concentrations of uranium have been detected but deposits of thorium minerals have been found. (author)

Concentration of Uranium Radioisotopes in Albanian Drinking Waters Measured by Alpha Spectrometry

Science.gov (United States)

Bylyku, Elida; Cfarku, Florinda; Deda, Antoneta; Bode, Kozeta; Fishka, Kujtim

2010-01-01

Uranium is a radioactive material that is frequently found in rocks and soil. When uranium decays, it changes into different elements that are also radioactive, including radon, a gas that is known to cause a lung cancer. The main concern with uranium in drinking water is harm to the kidneys. Public water systems are required to keep uranium levels at or below 500 mBq per liter to protect against kidney damage. Such an interest is needed due to safety, regulatory compliance and disposal issue for uranium in the environment since uranium is included as an obligatory controlled radionuclide in the European Legislation (Directive 98/83 CE of Council of 03.11.1998). The aim of this work is to measure the levels of uranium in drinking and drilled well waters in Albania. At first each sample was measured for total Alpha and total Beta activity. The samples with the highest levels of total alpha activity were chosen for the determination of uranium radioisotopes by alpha spectrometry. A radiochemical procedure using extraction with TBP (Tri-Butyl-Phosphate) is used in the presence of U232 as a yield tracer. Thin sources for alpha spectrometry are prepared by electrodepositing on to stainless steel discs. The results of the U238 activity measured in the different samples, depending from their geological origin range between 0.55-13.87 mBq/l. All samples measured results under the European Directive limits for U238 (5-500 mBq/1), Dose Coefficients according to Directive 96/29 EURATOM.

Detection of trisomy 7 in bronchial cells from uranium miners

Energy Technology Data Exchange (ETDEWEB)

Lechner, J.F.; Neft, R.E.; Belinsky, S.A. [and others

1995-12-01

New Mexico was the largest producer of uranium in the western world during 1960s and 1970s. Investigators at the University of New Mexico School of Medicine`s Epidemiology and Cancer Control Program have been conducting epidemiological studies on uranium miners over the past 2 decades. Currently, this cohort includes more than 3600 men who had completed at least 1 y of underground work experience in New Mexico by December 31, 1976. These miners, who are now in their 5th through 7th decades, the age when lung cancer incidence is highest, are at high risk for developing this disease because they were exposed to high levels of radon progeny in the mines, and they also smoked tobacco. However, not all people comparably exposed develop lung cancer; in fact, the lifetime risk of lung cancer for the smoking uranium miners has been projected by epidemiological analyses to be no higher than 50%. Therefore, the identification of gene alterations in bronchial epithelium would be a valuable tool to ascertain which miners are at greatest risk for lung cancer. The underlying significance of the current effort confirms the hypothesis that chronic exposure to high concentrations of {alpha}-particles and tobacco smoke produces genetically altered lung epithelial cells throughout the respiratory tract of some susceptible individuals before they develop clinical disease.

Detection of trisomy 7 in bronchial cells from uranium miners

International Nuclear Information System (INIS)

Lechner, J.F.; Neft, R.E.; Belinsky, S.A.

1995-01-01

New Mexico was the largest producer of uranium in the western world during 1960s and 1970s. Investigators at the University of New Mexico School of Medicine's Epidemiology and Cancer Control Program have been conducting epidemiological studies on uranium miners over the past 2 decades. Currently, this cohort includes more than 3600 men who had completed at least 1 y of underground work experience in New Mexico by December 31, 1976. These miners, who are now in their 5th through 7th decades, the age when lung cancer incidence is highest, are at high risk for developing this disease because they were exposed to high levels of radon progeny in the mines, and they also smoked tobacco. However, not all people comparably exposed develop lung cancer; in fact, the lifetime risk of lung cancer for the smoking uranium miners has been projected by epidemiological analyses to be no higher than 50%. Therefore, the identification of gene alterations in bronchial epithelium would be a valuable tool to ascertain which miners are at greatest risk for lung cancer. The underlying significance of the current effort confirms the hypothesis that chronic exposure to high concentrations of α-particles and tobacco smoke produces genetically altered lung epithelial cells throughout the respiratory tract of some susceptible individuals before they develop clinical disease

Teratogenicity of depleted uranium aerosols: A review from an epidemiological perspective

Directory of Open Access Journals (Sweden)

Panikkar Bindu

2005-08-01

Full Text Available Abstract Background Depleted uranium is being used increasingly often as a component of munitions in military conflicts. Military personnel, civilians and the DU munitions producers are being exposed to the DU aerosols that are generated. Methods We reviewed toxicological data on both natural and depleted uranium. We included peer reviewed studies and gray literature on birth malformations due to natural and depleted uranium. Our approach was to assess the "weight of evidence" with respect to teratogenicity of depleted uranium. 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. Discussion The two most significant challenges to establishing a causal pathway between (human parental DU exposure and the birth of offspring with defects are: i distinguishing the role of DU from that of exposure to other potential teratogens; ii documentation on the individual level of extent of parental DU exposure. Studies that use biomarkers, none yet reported, can help address the latter challenge. Thoughtful triangulation of the results of multiple studies (epidemiological and other of DU teratogenicity contributes to disentangling the roles of various potentially teratogenic parental exposures. This paper is just such an endeavor. Conclusion In aggregate the human epidemiological evidence is consistent with increased risk of birth defects in offspring of persons exposed to DU.

Analytical method of uranium (IV) and uranium (VI) in uranium ores and uranium-bearing rocks

International Nuclear Information System (INIS)

Shen Zhuqin; Zheng Yongfeng; Li Qingzhen; Zhong Miaolan; Gu Dingxiang

1995-11-01

The best conditions for keeping the original valences of uranium during the dissolution and separation procedure of geological samples (especially those micro uranium-bearing rock) were studied. With the exist of high concentration protectants, the sample was decomposed with concentration HF at 40 +- 5 degree C. The U(VI) was dissolved completely and formed stable complex UO 2 F 2 , the U(IV) was precipitated rapidly and carried by carrier. Quantitative separation was carried out immediately with suction. The decomposition of sample and separation of solid/liquid phases was completed within two minutes. After separation, the U(IV) and U(VI) were determined quantitatively with laser fluorescence or voltametry respectively according to the uranium content. The limit of detection for this method is 0.7 μg/g, RSD is 10.5%, the determinate range of uranium is 2 x 10 -6 ∼10 -1 g/g. The uranium contents and their valence state ratio were measured for more than one hundred samples of sand stone and granite, the accuracy and precision of these results are satisfactory for uranium geological research. (12 tabs.; 11 refs.)

Reduction of uranium hexafluoride to uranium tetrafluoride

International Nuclear Information System (INIS)

Chang, I.S.; Do, J.B.; Choi, Y.D.; Park, M.H.; Yun, H.H.; Kim, E.H.; Kim, Y.W.

1982-01-01

The single step continuous reduction of uranium hexafluoride (UF 6 ) to uranium tetrafluoride (UF 4 ) has been investigated. Heat required to initiate and maintain the reaction in the reactor is supplied by the highly exothermic reaction of hydrogen with a small amount of elemental fluorine which is added to the uranium hexafluoride stream. When gases uranium hexafluoride and hydrogen react in a vertical monel pipe reactor, the green product, UF 4 has 2.5g/cc in bulk density and is partly contaminated by incomplete reduction products (UF 5 ,U 2 F 9 ) and the corrosion product, presumably, of monel pipe of the reactor itself, but its assay (93% of UF 4 ) is acceptable for the preparation of uranium metal with magnesium metal. Remaining problems are the handling of uranium hexafluoride, which is easily clogging the flowmeter and gas feeding lines because of extreme sensitivity toward moisture, and a development of gas nozzel for free flow of uranium hexafluoride gas. (Author)

Precise coulometric titration of uranium in a high-purity uranium metal and in uranium compounds

International Nuclear Information System (INIS)

Tanaka, Tatsuhiko; Yoshimori, Takayoshi

1975-01-01

Uranium in uranyl nitrate, uranium trioxide and a high-purity uranium metal was assayed by the coulometric titration with biamperometric end-point detection. Uranium (VI) was reduced to uranium (IV) by solid bismuth amalgam in 5M sulfuric acid solution. The reduced uranium was reoxidized to uranium (VI) with a large excess of ferric ion at a room temperature, and the ferrous ion produced was titrated with the electrogenerated manganese(III) fluoride. In the analyses of uranium nitrate and uranium trioxide, the results were precise enough when the error from uncertainty in water content in the samples was considered. The standard sample of pure uranium metal (JAERI-U4) was assayed by the proposed method. The sample was cut into small chips of about 0.2g. Oxides on the metal surface were removed by the procedure shown by National Bureau of Standards just before weighing. The mean assay value of eleven determinations corrected for 3ppm of iron was (99.998+-0.012) % (the 95% confidence interval for the mean), with a standard deviation of 0.018%. The proposed coulometric method is simple and permits accurate and precise determination of uranium which is matrix constituent in a sample. (auth.)

31 CFR 540.317 - Uranium feed; natural uranium feed.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

Uranium exploration

International Nuclear Information System (INIS)

De Voto, R.H.

1984-01-01

This paper is a review of the methodology and technology that are currently being used in varying degrees in uranium exploration activities worldwide. Since uranium is ubiquitous and occurs in trace amounts (0.2 to 5 ppm) in virtually all rocks of the crust of the earth, exploration for uranium is essentially the search of geologic environments in which geologic processes have produced unusual concentrations of uranium. Since the level of concentration of uranium of economic interest is dependent on the present and future price of uranium, it is appropriate here to review briefly the economic realities of uranium-fueled power generation. (author)

Uranium

International Nuclear Information System (INIS)

1982-01-01

The development, prospecting, research, processing and marketing of South Africa's uranium industry and the national policies surrounding this industry form the headlines of this work. The geology of South Africa's uranium occurences and their positions, the processes used in the extraction of South Africa's uranium and the utilisation of uranium for power production as represented by the Koeberg nuclear power station near Cape Town are included in this publication

TECHNICAL REPORT ON TECHNOLOGICALLY ENHANCED NATURALLY OCCURRING RADIOACTIVE MATERIALS FROM URANIUM MINING, VOLUME II: INVESTIGATION OF POTENTIAL HEALTH, GEOGRAPHIC, AND ENVIRONMENTAL ISSUES OF ABANDONED URANIUM MINES

Science.gov (United States)

Volume II investigates the potential radiogenic risks from abandoned uranium mines and evaluates which may pose the greatest hazards to members of the public and to the environment. The intent of this report is to identify who may be most likely to be exposed to wastes at small a...

Evaluation of health effects in Sequoyah Fuels Corporation workers from accidental exposure to uranium hexafluoride

International Nuclear Information System (INIS)

Fisher, D.R.; Swint, M.J.; Kathren, R.L.

1990-05-01

Urine bioassay measurements for uranium and medical laboratory results were studied to determine whether there were any health effects from uranium intake among a group of 31 workers exposed to uranium hexafluoride (UF 6 ) and hydrolysis products following the accidental rupture of a 14-ton shipping cylinder in early 1986 at the Sequoyah Fuels Corporation uranium conversion facility in Gore, Oklahoma. Physiological indicators studied to detect kidney tissue damage included tests for urinary protein, casts and cells, blood, specific gravity, and urine pH, blood urea nitrogen, and blood creatinine. We concluded after reviewing two years of follow-up medical data that none of the 31 workers sustained any observable health effects from exposure to uranium. The early excretion of uranium in urine showed more rapid systemic uptake of uranium from the lung than is assumed using the International Commission on Radiological Protection (ICRP) Publication 30 and Publication 54 models. The urinary excretion data from these workers were used to develop an improved systemic recycling model for inhaled soluble uranium. We estimated initial intakes, clearance rates, kidney burdens, and resulting radiation doses to lungs, kidneys, and bone surfaces. 38 refs., 10 figs., 7 tabs

Evaluation of health effects in Sequoyah Fuels Corporation workers from accidental exposure to uranium hexafluoride

Energy Technology Data Exchange (ETDEWEB)

Fisher, D.R. (Pacific Northwest Lab., Richland, WA (USA)); Swint, M.J.; Kathren, R.L. (Hanford Environmental Health Foundation, Richland, WA (USA))

1990-05-01

Urine bioassay measurements for uranium and medical laboratory results were studied to determine whether there were any health effects from uranium intake among a group of 31 workers exposed to uranium hexafluoride (UF{sub 6}) and hydrolysis products following the accidental rupture of a 14-ton shipping cylinder in early 1986 at the Sequoyah Fuels Corporation uranium conversion facility in Gore, Oklahoma. Physiological indicators studied to detect kidney tissue damage included tests for urinary protein, casts and cells, blood, specific gravity, and urine pH, blood urea nitrogen, and blood creatinine. We concluded after reviewing two years of follow-up medical data that none of the 31 workers sustained any observable health effects from exposure to uranium. The early excretion of uranium in urine showed more rapid systemic uptake of uranium from the lung than is assumed using the International Commission on Radiological Protection (ICRP) Publication 30 and Publication 54 models. The urinary excretion data from these workers were used to develop an improved systemic recycling model for inhaled soluble uranium. We estimated initial intakes, clearance rates, kidney burdens, and resulting radiation doses to lungs, kidneys, and bone surfaces. 38 refs., 10 figs., 7 tabs.

Measurements of 234U, 238U and 230Th in excreta of uranium-mill crushermen

International Nuclear Information System (INIS)

Fisher, D.R.; Jackson, P.O.; Brodacynski, G.G.; Scherpelz, R.I.

1982-07-01

Uranium and thorium levels in excreta of uranium mill crushermen who are routinely exposed to airborne uranium ore dust were measured. The purpose was to determine whether 230 Th was preferentially retained over either 234 U or 238 U in the body. Urine and fecal samples were obtained from fourteen active crushermen with long histories of exposure to uranium ore dust, plus four retired crushermen and three control individuals for comparison. Radiochemical procedures were used to separate out the uranium and thorium fractions, which were then electroplated on stainless steel discs and assayed by alpha spectrometry. Significantly greater activity levels of 234 U and 238 U were measured in both urine and fecal samples obtained from uranium mill crushermen, indicating that uranium in the inhaled ore dust was cleared from the body with a shorter biological half-time than the daughter product 230 Th. The measurements also indicated that uranium and thorium separate in vivo and have distinctly different metabolic pathways and transfer rates in the body. The appropriateness of current ICRP retention and clearance parameters for 230 Th in ore dust is questioned

Determination of the oxygen-metal-ratio of uranium-americium mixed oxides

International Nuclear Information System (INIS)

Bartscher, W.

1982-01-01

During the dissolution of uranium-americium mixed oxides in phosphoric acid under nitrogen tetravalent uranium is oxidized by tetravalent americium. The obtained hexavalent uranium is determined by constant potential coulometry. The coulombs measured are equivalent to the oxygen in excess of the minimum composition of UO 2 x AmO 1 . 5 . The total uranium content of the sample is determined in a subsequent coulometric titration. The oxygen-metal ratio of the sample can be calculated for a given uranium-americium ratio. An excess of uranium dioxide is necessary in order to suppress the oxidation of water by tetravalent americium. The standard deviation of the method is 0.0017 O/M units. (orig.) [de

Translocation of uranium from water to foodstuff while cooking

International Nuclear Information System (INIS)

Krishnapriya, K.C.; Baksi, Ananya; Chaudhari, Swathi; Gupta, Soujit Sen; Pradeep, T.

2015-01-01

Highlights: • Rice can efficiently uptake uranium from water contaminated with uranyl nitrate hexahydrate (UO 2 (NO 3 ) 2.6 H 2 O), while cooking. • Unusual uranium uptake to the extent of about 1000 ppm is observed when rice is cooked in highly concentrated uranium contaminated water (1240 ppm). • Nature of interaction of uranium with carbohydrates is probed using small monosaccharides like glucose and mannose. • Electrospray ionization mass spectrometry showed UO 2 2+ to be the most stable species in water in such solutions which can form complexes with sugars. • The species (UO 2 2+ ) is also observed in the case of water exposed to the common mineral, uranium oxide (UO 2 ) and similar type of complexation is observed with sugars. - Abstract: The present work report the unusual uranium uptake by foodstuff, especially those rich in carbohydrates like rice when they are cooked in water, contaminated with uranium. The major staple diet in South Asia, rice, was chosen to study its interaction with UO 2 2+ , the active uranium species in water, using inductively coupled plasma mass spectrometry. Highest uptake limit was checked by cooking rice at very high uranium concentration and it was found to be good scavenger of uranium. To gain insight into the mechanism of uptake, direct interaction of UO 2 2+ with monosaccharides was also studied, using electrospray ionization mass spectrometry taking mannose as a model. The studies have been done with dissolved uranium salt, uranyl nitrate hexahydrate (UO 2 (NO 3 ) 2 ·6H 2 O), as well as the leachate of a stable oxide of uranium, UO 2 (s), both of which exist as UO 2 2+ in water. Among the eight different rice varieties investigated, Karnataka Ponni showed the maximum uranium uptake whereas unpolished Basmati rice showed the minimum. Interaction with other foodstuffs (potato, carrot, peas, kidney beans and lentils) with and without NaCl affected the extent of chemical interaction but was not consistent with the

Metabolic fate and evaluation of injury in rats and dogs following exposure to the hydrolysis products of uranium hexafluoride: implications for a bioassay program related to potential releases of uranium hexafluoride, July 1979-October 1981

International Nuclear Information System (INIS)

Morrow, P.E.; Leach, L.J.; Smith, F.A.

1982-12-01

This final report summarizes the experimental studies undertaken in rats and dogs in order to help provide adequate biological bases for quantifying and evaluating uranium hexafluoride (UF 6 ) exposures. Animals were administered the hydrolysis products of UF 6 by inhalation exposures, intratracheal instillations and intravenous injections. Attention was given to dose-effect relationships appropriate to the kidney, the unique site of subacute toxicity; to the rates of uranium excretion; and to uranium retention in renal tissue. These criteria were examined in both naive and multiply-exposed animals. The findings of these studies partly substantiate the ICRP excretion model for hexavalent uranium; generally provide a lower renal injury threshold concentration than implicit in the MPC for natural uranium; indicate distinctions in response (for example, uranium excretion) are based on exposure history; compare and evaluate various biochemical indices of renal injury; raise uncertainties about prevailing views of reversible renal injury, renal tolerance and possible hydrogen fluoride synergism with uranium effects; and reveal species differences in several areas, for example, renal retention of uranium. While these studies present some complicating features to extant bioassay practice, they nevertheless supply data supportive of the bioassay concept

Contribution to uranium geochemistry in intrusive granites; Contribution a la geochimie de l'uranium dans les granites intrusifs

Energy Technology Data Exchange (ETDEWEB)

Coulomb, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1959-01-15

This work aims to define the position of a certain number of French granitic deposits within the field of the geochemistry of granites in general, and of the geochemistry of uranium in particular. The regions concerned are: - 3 French Hercynian ranges, in the Vendee, in Brittany and in the Morvan, - 1 African range, probably precambrian, of the Hoggar. For each range, the petrochemical framework is first of all determined and then the degree of chemical homogeneity of the rocks is evaluated. In the petrochemical groups thus obtained the geochemical behaviour of the uranium is studied. From a point of view of the geochemistry of the granites under investigation, a comparison of the laws of distribution of the major elements in the 4 ranges shows up a convergence of average composition which was not anticipated by geological and petrographic considerations alone. The statistical and geochemical distribution laws of the total uranium as a function of the petrochemical variations are established. A study of the chemical forms of uranium in the rocks has drawn an attention to the qualitative and quantitative importance of the fraction of this uranium soluble in dilute acids. We have therefore reconsidered on the one hand, the laws of distribution of the insoluble uranium, which represents essentially the uranium fixed in crystalline structures (zircon, allanite...), and we have justified on the other hand the interest presented by the soluble uranium: this, although more complex in character, presents a geochemical unity in post magmatic phenomena which makes possible to find a genetic connection between the uraniferous deposits and the intrusive massifs. Finally we have given a plan of the geochemical cycle of uranium, in which we hope to have provided some more accurate data on the igneous phase. (author) [French] Le but du travail presente est de situer sur le plan de la geochimie des granites en general, sur le plan de la geochimie de l'uranium en particulier

Uranium conversion; Urankonvertering

Energy Technology Data Exchange (ETDEWEB)

Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina [Swedish Defence Research Agency (FOI), Stockholm (Sweden)

2006-03-15

FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF{sub 6} and UF{sub 4} are present require equipment that is made of corrosion resistant material.

Development growth of uranium reserves during mining

International Nuclear Information System (INIS)

Giroux, M.

1989-01-01

According to the 1988 issue of the Nuclear Energy Agency report 'Uranium Resources, Production and Demand' (the Red Book), total uranium resources remained constant, and compare with those given in the 1986 issue. However, the low cost category of the Reasonably Assured Resources (RAR), that is to say potentially mineable reserves under present market conditions, presents a different picture. These show a decrease of 54 000 tonnes U, or about 3.5%, from the 1 January 1985 level. It seems insignificant until compared with what was removed from the ground - only a quarter of the 71 500 tonnes U of the low cost uranium that was extracted during 1985 and 1986 was renewed by the industry. This is probably related to the low level of exploration activity since 1983. Moreover, new uranium might be not as easy to find as some past discoveries have led us to believe. While in 1988 it appears there is enough low cost uranium to supply existing reactors, the picture quickly changes. From 1991 onwards, for 30 years' supply for existing reactors, uranium will have to come from RAR in the higher cost category. (author)

Early results of studies on the levels of depleted uranium excreted by Balkan residents

International Nuclear Information System (INIS)

Priest, N.D.; Thirlwell, M.

2002-01-01

Urine samples collected from residents of Bosnia and Herzegovina and Kosovo were analysed to determine their natural and depleted uranium content using MC-ICP-MS. All may have been exposed to depleted uranium released as a consequence of the deployment of armour-piercing rounds by the US Air Force. A 236 U tracer was employed to determine chemical recovery. Early results suggest that the levels of natural and depleted uranium excretion by the subjects, which ranged in age from 1 to 71 years, ranged from 2.8 - 58.2 ng d -1 and 1.3 - 46.3 ng d -1 , respectively. The results suggest accumulated body burdens of depleted uranium ranging from close to zero to 46 μg. All the body burdens predicted are lower than published values for the uranium content of the body (90μg) and health effects are not predicted. Further studies are underway to check the provenance of the results. (author)

Uranium speciation in Fernald soils

International Nuclear Information System (INIS)

Morris, D.E.; Conradson, S.D.; Tait, C.D.; Chisholm-Brause, C.J.; Berg, J.; Musgrave, J.

1992-01-01

This report details progress made from January 1 to May 31, 1992 in this analytical support task to determine the speciation of uranium in contaminated soil samples from the Fernald Environmental Management Project site under the auspices of the Uranium in Soils Integrated Demonstration funded through the US DOE's Office of Technology Development. The authors' efforts have focused on characterization of soil samples collected by S.Y. Lee (Oak Ridge National Laboratory) from five locales at the Fernald site. These were chosen to sample a broad range of uranium source terms. On the basis of x-ray absorption spectroscopy data, they have determined that the majority of uranium (> 80--90%) exists in the hexavalent oxidation state for all samples examined. This is a beneficial finding from the perspective of remediation, because U(VI) species are more soluble in general than uranium species in other oxidation states. Optical luminescence data from many of the samples show the characteristic structured yellow-green emission from the uranyl (UO 2 2+ ) moiety. The luminescence data also suggest that much of the uranium in these soils is present as well-crystallized UO 2 2+ species. Some clear spectroscopic distinctions have been noted for several samples that illustrate significant differences in the speciation (1) from site to site, (2) within different horizons at the same site, and (3) within different size fractions of the soils in the same horizon at the same site. This marked heterogeneity in uranyl speciation suggests that several soil washing strategies may be necessary to reduce the total uranium concentrations within these soils to regulatory limits

Studies on fission tracks and distributions of uranium and rare earths in granite materials

International Nuclear Information System (INIS)

Matsuda, Hiroshi; Sakanoue, Masanobu

1987-01-01

Many materials contain fossil records of the slow spontaneous fission of uranium they contain as an impurity. Fission fragments, heavy charged particles released in each fission event, produce microscopic trails of radiation damage that may persist over geological times and may be developed to a size observable under an optical microscope by a suitable etching treatment. Such tracks are also produced by fissions induced by thermal neutron irradiation of the uranium. When the material is heated sufficiently, it anneals and the the microscopic trails become shorter and narrower. The track density decreases, because the chemical etchant will not reach some of the shortened tracks. Measurements of track densities before and after annealing can be used, along with laboratory studies of annealing rates, to determine the annealing temperature. Also, the track density of induced fissions is related to the concentration of uranium and the fluence of neutrons to which it was exposed. If the track density due to induced fissions can be distinguished from that due to fossil tracks, estimates of either the concentration or the fluence can be made if the other is known. Two such materials (one a fragment of a granite paving stone, the other a piece of stained glass from a cathedral window) that had been exposed to the atomic bomb at Nagasaki were used in the present work. The fossil record in zircons in the granite was used to estimate the temperature to which it had been exposed in the bombing. Induced fissions were used to estimate the concentration of uranium in the zircons. Nonuniform heating and cooling and nearly uniform exposure to the neutrons make the granite sample unsuitable for determining the neutron fluence from the bomb. Induced fissions in the stained glass were used to estimate the concentration of uranium and the thermal neutron fluence from the A-bomb. Annealing of tracks in glass was also studied

Determination of uranium in clinical and environmental samples by FIAS-ICPMS

International Nuclear Information System (INIS)

Karpas, Z.; Lorber, A.; Halicz, L.; Gavrieli, I.

1998-01-01

Uranium may enter the human body through ingestion or inhalation. Ingestion of uranium compounds through the diet, mainly drinking water, is a common occurrence, as these compounds are present in the biosphere. Inhalation of uranium-containing particles is mainly an occupational safety problem, but may also take place in areas where uranium compounds are abundant. The uranium concentration in urine samples may serve as an indication of the total uranium body content. A method based on flow injection and inductively coupled plasma mass spectrometry (FIAS-ICPMS) was found to be most suitable for determination of uranium in clinical samples (urine and serum), environmental samples (seawater, wells and carbonate rocks) and in liquids consumed by humans (drinking water and commercial beverages). Some examples of the application of the FIAS-ICPMS method are reviewed and presented here

Assessment of uranium resources and supply

International Nuclear Information System (INIS)

1991-04-01

Uranium as nuclear fuel is an important energy resource, which generates about one-sixth of the world's total electricity generated in 1989. The current nuclear electricity generating capacity of 318 GW(e) is expected to grow by over 38% to 440 GW(e) in the year 2005. The world's uranium requirements are expected to increase similarly from about 52,000 t U in 1989 to over 70,000 t U in 2005. Beyond this time the uranium requirements are projected to reach over 80,000 t U in 2030. It was the objective of the Technical Committee Meeting on Assessment of Uranium Resources and Supply, organized by the IAEA and held in Vienna, between 29 August - 1 September 1989, to attract specialists in this field and to provide a forum for the presentation of reports on the methodologies and actual projects carried out in the different countries. Of special interest was the participation of specialists from some countries which did not or only occasionally co-operate with the IAEA in the projects related to the assessment of uranium resources and supply. A separate abstract was prepared for each of the 19 papers. Refs, figs and tabs

Evaluation of the radiation doses to uranium mine employees exposed to external gamma radiation

International Nuclear Information System (INIS)

Young, J.G.; Wilson, O.J.

1983-02-01

Factors to convert a personal monitor badge reading to an effective dose equivalent are given for several exposure geometries encountered in uranium mines. Factors are also given that relate a free air absorbed dose measurement to an effective dose equivalent. In addition, factors are reported which can be used to estimate the dose equivalent to the testes, ovaries and active bone marrow

The Ellweiler uranium plant - a demolition and recycling project

International Nuclear Information System (INIS)

Mika, S.; Rohr, T.; Seehars, R.; Feser, A.

1999-01-01

The uranium plant at Ellweiler, district of Birkenfeld, was used for the production and storage of uranium concentrates. The owner of the Ellweiler uranium plant (UAE), Gewerkschaft Brunhilde GmbH, ceased processing uranium ore and recycling in 1989 and has been in liquidation since September 1991. The State of Rhineland-Palatinate, had safety measures adopted in a first step, getting the plant into a safe state by former plant personnel. The entire plant was demolished in a second step. The contract for demolishing the former uranium plant was awarded to ABB Reaktor as the general contractor in August 1996. Demolition work was carried out between April 1997 and May 1999. A total of approx. 7900 Mg of material was disposed of. At present, recultivation measures are being carried out. (orig.) [de

Case-control study of lung cancer among workers at a uranium processing plant

International Nuclear Information System (INIS)

Cookfair, D.L.

1982-01-01

The purpose of this case-control study was to investigate the relationship between exposure to radiation resulting from the inhalation of uranium dust and the dust of uranium-bearing compounds and death due to lung cancer. Cases and controls were chosen from a cohort of white male workers employed at one uranium processing plant during World War II. The 330 cases consisted of all lung cancer deaths occurring in the cohort between 1943 and 1973. Level of exposure to radiation and other potential workplace carcinogens was determined for each worker using process manuals, industrial hygiene reports, air monitoring data and individual work histories. Smoking status and information regarding medical variables was determined from employee medical records. Cumulative radiation lung dose among study population members ranged from 0 to 75 rads. Data were analyzed using Mantel-Haenszel stratified analysis and logistic regression. Relative risk was found to increase with increasing level of lung dose exposure even after controlling for age, smoking status and other workplace exposures, but only for those who were over the age of 44 when first exposed. A statistically significant excess in risk was found for men in this hire age group with a cumulative lung dose of 20 rads or more. The risk associated with the overall work environment was also investigated using a summary measure of total workplace exposure called chemical rank. A similar relationship existed between chemical rank and lung cancer to that found for cumulative lung dose and lung cancer

Uranium facilitated transport by water-dispersible colloids in field and soil columns

Energy Technology Data Exchange (ETDEWEB)

Crancon, P.; Pili, E. [CEA Bruyeres-le-Chatel, DIF, 91 (France); Charlet, L. [Univ Grenoble 1, Lab Geophys Interne and Tectonophys LGIT OSUG, CNRS, UJF, UMR5559, F-38041 Grenoble 9 (France)

2010-07-01

The transport of uranium through a sandy podsolic soil has been investigated in the field and in column experiments. Field monitoring, numerous years after surface contamination by depleted uranium deposits, revealed a 20 cm deep uranium migration in soil. Uranium retention in soil is controlled by the {<=} 50 {mu}m mixed humic and clayey coatings in the first 40 cm i.e. in the E horizon. Column experiments of uranium transport under various conditions were run using isotopic spiking. After 100 pore volumes elution, 60% of the total input uranium is retained in the first 2 cm of the column. Retardation factor of uranium on E horizon material ranges from 1300 (column) to 3000 (batch). In parallel to this slow uranium migration, we experimentally observed a fast elution related to humic colloids of about 1-5% of the total-uranium input, transferred at the mean pore-water velocity through the soil column. In order to understand the effect of rain events, ionic strength of the input solution was sharply changed. Humic colloids are retarded when ionic strength increases, while a major mobilization of humic colloids and colloid-borne uranium occurs as ionic strength decreases. Isotopic spiking shows that both {sup 238}U initially present in the soil column and {sup 233}U brought by input solution are desorbed. The mobilization process observed experimentally after a drop of ionic strength may account for a rapid uranium migration in the field after a rainfall event, and for the significant uranium concentrations found in deep soil horizons and in groundwater, 1 km downstream from the pollution source. (authors)

Vapor corrosion of aluminum cladding alloys and aluminum-uranium fuel materials in storage environments

International Nuclear Information System (INIS)

Lam, P.; Sindelar, R.L.; Peacock, H.B. Jr.

1997-04-01

An experimental investigation of the effects of vapor environments on the corrosion of aluminum spent nuclear fuel (A1 SNF) has been performed. Aluminum cladding alloys and aluminum-uranium fuel alloys have been exposed to environments of air/water vapor/ionizing radiation and characterized for applications to degradation mode analysis for interim dry and repository storage systems. Models have been developed to allow predictions of the corrosion response under conditions of unlimited corrodant species. Threshold levels of water vapor under which corrosion does not occur have been identified through tests under conditions of limited corrodant species. Coupons of aluminum 1100, 5052, and 6061, the US equivalent of cladding alloys used to manufacture foreign research reactor fuels, and several aluminum-uranium alloys (aluminum-10, 18, and 33 wt% uranium) were exposed to various controlled vapor environments in air within the following ranges of conditions: Temperature -- 80 to 200 C; Relative Humidity -- 0 to 100% using atmospheric condensate water and using added nitric acid to simulate radiolysis effects; and Gamma Radiation -- none and 1.8 x 10 6 R/hr. The results of this work are part of the body of information needed for understanding the degradation of the A1 SNF waste form in a direct disposal system in the federal repository. It will provide the basis for data input to the ongoing performance assessment and criticality safety analyses. Additional testing of uranium-aluminum fuel materials at uranium contents typical of high enriched and low enriched fuels is being initiated to provide the data needed for the development of empirical models

Properties, use and health effects of depleted uranium

International Nuclear Information System (INIS)

Aloraby, M.N.

2010-01-01

Depleted uranium (DU), a waste product of uranium enrichment, has several civilian and military applications. It was used as armor-piercing ammunition in international military conflicts and was claimed to contribute to health problems, known as the Gulf War Syndrome. This led to renewed efforts to assess the environmental consequences and health impact of DU use. The radiological and chemical properties of DU can be compared to those of natural uranium, which is ubiquitously present in soil at a typical concentration of 3 mg/kg. Natural uranium has the same chemo toxicity, but its radiotoxicity is 60% higher. Due to low specific radioactivity and the dominance of alpha radiation no acute risk is attributed to external exposure to DU. The major risk is DU dust, generated when DU ammunition hits hard targets. After deposition on the ground, resuspension takes place, if the DU containing particle size sufficiently small. However, transfer to drinking water or locally produced food has little potential to lead to significant exposure to DU. Since poor solubility of uranium compounds and lack of information on speciation precludes the use of radioecological models for exposure assessment, bio monitoring has to be used for assessing exposed persons. With the exception of crews of military vehicles having been hit by DU penetrators, no body burdens above the range of values for natural uranium have been found. Therefore, observable health effects are not expected and residual cancer risk estimates have to be based on theoretical considerations. They appear to be very minor for all post-conflict situations, i.e. a fraction of those expected from natural radiation. (author)

Use of gamma camera for measurement of the internal contamination with depleted uranium

International Nuclear Information System (INIS)

Spaic, R.; Markovic, S.; Pavlovic, S.; Pavlovic, R.; Ajdinovic, B.; Baskot, B.; Djurovic, B.

2000-01-01

Depleted uranium from radioactive wastes is used for manufacturing bullets used in Iraq, Republic of Serbia and Yugoslavia. These bullets are extremely dense and capable of penetrating heavily armored vehicles. Their medical importance lies in the fact that the bullets contain seventy percent depleted uranium which creates aerosolized particles less than five microns in diameter, small enough to be inhaled, after spontaneous bullet burn at impact. Nuclear medicine scientists must be aware of this and be prepared to measure internal contamination of persons exposed to this radioactive material. Whole body counters (WBC) represent appropriate equipment for this purpose but their availability in developing countries is not sufficient. Gamma camera is an alternative. The minimum detectable activity (MDA) of depleted uranium, iodine and technetium for gamma cameras was measured in this paper. Low energy X-ray 100 KeV with 20% windows are used for the depleted uranium detection. About 40% gamma emissions from depleted uranium fall within these limits. The activities measured (50-100 Bq) are about ten times higher then on WBC (5 Bq). This does not limit the use of gamma cameras for measurement of lung or whole body internal contamination with depleted uranium. (author)

Uranium

International Nuclear Information System (INIS)

Mackay, G.A.

1978-01-01

The author discusses the contribution made by various energy sources in the production of electricity. Estimates are made of the future nuclear contribution, the future demand for uranium and future sales of Australian uranium. Nuclear power growth in the United States, Japan and Western Europe is discussed. The present status of the six major Australian uranium deposits (Ranger, Jabiluka, Nabarlek, Koongarra, Yeelerrie and Beverley) is given. Australian legislation relevant to the uranium mining industry is also outlined

Epidemiological study on lung cancer of uranium miners

International Nuclear Information System (INIS)

Yuan Liyun; Gu Juanjuan

1994-01-01

Lung cancer among 13360 male workers of 5 uranium mines were investigated. During the period of observation (Jan, 1971-Dec. 1985) 35 lung cancers were registered; among them 24 were in exposed group and 11 in control group. Standard mortality of lung cancer for these two groups were 21.42·10 -5 and 15.94·10 -5 , respectively. SMR were 1.83 (exposed group) and 1.44 (control group) (P<0.01). The average latent period of lung cancer in exposed group was 17.5 years, and the average cumulative exposure dose to radon daughters was 168 WLM. The average age of workers dead of lung cancer was 47.83 years. The excess RR coefficient of lung cancer was 1.07%/WLM. SMR increased with increasing cumulative exposure dose to radon daughters. The adjusted mortality of long cancer of smokers in exposed group was obviously higher than that of nonsmokers

Effects of enriched uranium on developing brain damage of neonatal rats

International Nuclear Information System (INIS)

Gu Guixiong; Zhu Shoupeng; Wang Liuyi; Yang Shuqin; Zhu Lingli

2001-01-01

The model of irradiation-induced brain damage in vivo was settled first of all. The micro-auto-radiographic tracing showed that when the rat's brain at postnatal day after lateral ventricle injection with enriched uranium 235 U the radionuclides were mainly accumulated in the nucleus. At the same time autoradiographic tracks appeared in the cytoplasm and interval between cells. The effects of cerebrum exposure to alpha irradiation by enriched uranium on somatic growth and neuro-behavior development of neonatal rats were examined by determination of multiple parameters. In the growth and development of the neonatal rat's cerebrum exposure to enriched uranium, the somatic growth such as body weight and brain weight increase was lower significantly. The data indicated that the neonatal wistar rats having cerebrum exposure to alpha irradiation by enriched uranium showed delayed growth and abnormal neuro-behavior. The changes of neuron specific enolase (NSE), interleukin-1 β (IL- β), superoxide dismutase (SOD), and endothelin (ET) in cerebellum, cerebral cortex, hippocampus, diencephalons of the rat brain after expose to alpha irradiation by enriched uranium were examined with radioimmunoassay. The results showed that SOD and ET can be elevated by the low dose irradiation of enriched uranium, and can be distinctly inhibited by the high dose. The data in view of biochemistry indicated firstly that alpha irradiation from enriched uranium on the developing brain damage of neonatal rats were of sensibility, fragility and compensation in nervous cells

Effects of enriched uranium on developing brain damage of neonatal rats

Energy Technology Data Exchange (ETDEWEB)

Guixiong, Gu; Shoupeng, Zhu; Liuyi, Wang; Shuqin, Yang; Lingli, Zhu [Suzhou Medical College, Suzhou (China)

2001-04-01

The model of irradiation-induced brain damage in vivo was settled first of all. The micro-auto-radiographic tracing showed that when the rat's brain at postnatal day after lateral ventricle injection with enriched uranium {sup 235}U the radionuclides were mainly accumulated in the nucleus. At the same time autoradiographic tracks appeared in the cytoplasm and interval between cells. The effects of cerebrum exposure to alpha irradiation by enriched uranium on somatic growth and neuro-behavior development of neonatal rats were examined by determination of multiple parameters. In the growth and development of the neonatal rat's cerebrum exposure to enriched uranium, the somatic growth such as body weight and brain weight increase was lower significantly. The data indicated that the neonatal wistar rats having cerebrum exposure to alpha irradiation by enriched uranium showed delayed growth and abnormal neuro-behavior. The changes of neuron specific enolase (NSE), interleukin-1 {beta} (IL- {beta}), superoxide dismutase (SOD), and endothelin (ET) in cerebellum, cerebral cortex, hippocampus, diencephalons of the rat brain after expose to alpha irradiation by enriched uranium were examined with radioimmunoassay. The results showed that SOD and ET can be elevated by the low dose irradiation of enriched uranium, and can be distinctly inhibited by the high dose. The data in view of biochemistry indicated firstly that alpha irradiation from enriched uranium on the developing brain damage of neonatal rats were of sensibility, fragility and compensation in nervous cells.

Uranium, the joint facilities, disarmament and peace

International Nuclear Information System (INIS)

Anon.

1984-07-01

The Australian Government recognises that the only outcome which is ultimately acceptable is total nuclear disarmament. One of the issues addressed in this document is that of the export of Australian uranium. It is argued that by refusing to supply uranium Australia would be making a symbolic gesture which would have the reverse effect to that which was intended. It would weaken the non-proliferation regime and Australia's voice in arms control and disarmament forums

Evaluation of transport properties of nanofiltration membranes exposed to radioactive liquid waste

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Elizabeth E.M.; Barbosa, Celina C.R.; Bastos, Edna T.R., E-mail: eemo@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeira, RJ (Brazil); Afonso, Julio C., E-mail: Julio@iq.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica. Dept. de Quimica Analitica

2011-07-01

The application of membrane separation processes (PSM) for treatment of radioactive waste requires the selection of a suitable membrane for the treatment of waste, as the membrane will be directly exposed to the radioactive liquid waste, and also exposed to ionizing radiation. The nanofiltration membrane is most suitable for treatment of radioactive waste, since it has high rejection of multivalent ions. Usually the membranes are made of polymers and depending on the composition of the waste, type and dose of radiation absorbed may be changes in the structure of the membrane, resulting in loss of its transport properties. We tested two commercial nanofiltration membranes: NF and SW Dow/Filmtec. The waste liquid used was obtained in the process of conversion of uranium hexafluoride gas to solid uranium dioxide, known as 'carbonated water'. The membranes were characterized as their transport properties (hydraulic permeability, permeate flux and salt rejection) before and after their immersion in the waste for 24 hours. The surface of the membranes was also evaluated by SEM and FTIR. It was observed that in both the porosity of the membrane selective layer was altered, but not the membrane surface charge, which is responsible for the selectivity of the membrane. The NF membranes and SW showed uranium ion rejection of 64% and 55% respectively. (author)

Uranium in Niger; L'uranium au Niger

Energy Technology Data Exchange (ETDEWEB)

Gabelmann, E

1978-03-15

This document presents government policy in the enhancement of uranium resources, existing mining companies and their productions, exploitation projects and economical outcome related to the uranium mining and auxiliary activities. [French] Le document presente la politique de l'Etat dans le cadre de la mise en valeur des ressources d'uranium, les societes minieres existantes et leurs productions, les projets d'exploitation d'uranium et les retombees economiques liees aux activites uraniferes et connexes.

Basic status of uranium mine production at the beginning of the new century

International Nuclear Information System (INIS)

Tan Chenglong

2005-01-01

At the beginning of the new century, the global uranium mine production declined slightly, the spot uranium price was close to or slightly higher than that of the last century. The uranium consumption in global nuclear electricity generation does not fluctuate greatly, remains stable as a whole. Although certain accidents have taken place during the period of uranium mine production, uranium production remains stable, uranium's demand and supply remain balanced basically. In the global uranium mine production at the beginning of the new century, production from hard rock uranium mines still plays the leading role, and production from in-situ leachable sandstone-type uranium mines increases by a small margin and makes up one fifth of the total global uranium mine production. Several transnational uranium industry companies have become the main stockholders of low cost uranium production centers all around the world. Most mining uranium deposits and uranium production centers have centralized in a few countries. The globalized distribution of uranium resources during the progress of the world's economy globalization has taken shape in the uranium industry. (authors)

Comparative toxicity in rats vs hamsters of inhaled radon daughters with and without uranium ore dust

International Nuclear Information System (INIS)

Gaven, J.C.; Palmer, R.F.; McDonald, K.E.; Lund, J.E.; Stuart, B.O.

1977-01-01

Simultaneous exposures of rats and hamsters to inhaled radon daughters, with and without uranium ore dust, were performed daily for five months. Pulmonary pathology developing in 6 to 13 mo after cessation of daily exposures included interstitial fibrosis, emphysema, epithelial hyperplasia, squamous metaplasia, and malignant neoplasia. Rats showed a greater variety and more severe response to these uranium mine inhalation exposures than did hamsters. Inhalation of radon daughters with uranium ore dust displayed the site of greatest damage, including squamous carcinoma, from the nasopharynx to the lungs. Sixty percent of the rats exposed to radon daughters with ore dust developed primary pulmonary carcinomas, providing an appropriate short-term experimental animal model for investigation of respiratory tract carcinogenesis in uranium miners

Exploration and uranium mining in Niger

International Nuclear Information System (INIS)

Moussa, M.

2014-01-01

features are important in trapping the mineralisation which is often of roll front type, either reduced consisting in pitchblende and coffinite (Akouta, Arlit, Afasto, Madaouela) or oxidized (Imouraren). The main exploration companies of Uranium in the basin of Tim Mersoï (Northern Iullemenden) are: • AREVA-Niger for the uranium-bearing prospecting permits of Imouraren, Afouday, Agebout; • Cominak for the uranium-bearing prospecting permit Western Afasto; • NorthWestern Mineral Ventures Inc for the uranium-bearing prospecting permits Irhazer and Ingal; • North Atlantic Resources Ltd. for the uranium-bearing prospecting permit Abélajouad; • CNUC for the uranium-bearing permit of Tiguida • Goviex for uranium permit of Madaouéla; • International Uranium Ltd for the uranium-bearing prospecting permits of Agelal I, II, III, IV and Aserka I, II, III, IV; • Total Uranium Corporation for the licences of Chock Negouran I, II, III and IV; • Trend Field Holding SA for the uranium-bearing prospecting permits Tagaza II and IV. (author)

The relationship between uranium distribution and some major crustal features in Canada

International Nuclear Information System (INIS)

Darnley, A.G.

1982-01-01

The availability of reconnaissance scale geochemical maps for large areas of Canada enables spatial associations between major crustal structures and surface uranium content to be identified. Maps of the distribution of uranium for an area greater than 2 million km 2 compiled from airborne gamma-ray spectrometry data are supplemented by maps for uranium, based on stream and lake sediment and some bore hole sampling. These are examined in relation to gravity, aeromagnetic and geological maps. The radioelement distribution can be related in detail to exposed bedrock and surface geology, but in addition there is evidence of the control of uranium distribution by major structural features which are marked by granitoids containing elevated levels of radioelements; several of these granitoids are associated with large negative Bouguer gravity anomalies. The distribution of such granitoids appears to be related to 'megashears', as in the case of the South Mountain batholith in Nova Scotia, or zones of tension. A belt of uranium enrichment, the Athabasca axis which is characterized by uraniferous granitoids with negative Bouguer gravity anomalies and associated tension faulting extends 2500 km northeastward from Edmonton, Alberta to the Melville Peninsula. This structure passes under the Athabasca basin which contains many large uranium deposits. (author)

Uranium hydrogeochemical and stream sediment reconnaissance in the San Juan Mountains, Southwest Colorado

Energy Technology Data Exchange (ETDEWEB)

Maxwell, J.C.

1977-02-01

From 1995 sites in the San Juan Mountains area, 1706 water and 1982 sediment samples were collected during June--July 1976 and analyzed for uranium. The area includes the southern third of the Colorado mineral belt which has yielded rich ores of gold, silver, copper, lead, zinc, and molybdenum. The broadly domed mountains are capped by 2500 m of Tertiary volcanics, deeply eroded to expose a Precambrian crystalline core. Adjacent plateaus underlain by Mesozoic sedimentary rocks were included in the reconnaissance. Average value of uranium in water samples from mountains was less than 0.5 ppB, from plateaus was 1 to 2 ppB, from Mancos shale areas exceeded 2 ppB. Anomalous sediment samples, 40 ppM uranium, came from near Storm King Mountain and upper Vallecito Creek. Other anomalous areas, including the Lake City mining district, were well defined by 4 to 30 ppM uranium in sediment and 3 to 30 ppB uranium in water. Anomalous areas not previously reported indicate favorable areas for future exploration.

Uranium hydrogeochemical and stream sediment reconnaissance in the San Juan Mountains, Southwest Colorado

International Nuclear Information System (INIS)

Maxwell, J.C.

1977-02-01

From 1995 sites in the San Juan Mountains area, 1706 water and 1982 sediment samples were collected during June--July 1976 and analyzed for uranium. The area includes the southern third of the Colorado mineral belt which has yielded rich ores of gold, silver, copper, lead, zinc, and molybdenum. The broadly domed mountains are capped by 2500 m of Tertiary volcanics, deeply eroded to expose a Precambrian crystalline core. Adjacent plateaus underlain by Mesozoic sedimentary rocks were included in the reconnaissance. Average value of uranium in water samples from mountains was less than 0.5 ppB, from plateaus was 1 to 2 ppB, from Mancos shale areas exceeded 2 ppB. Anomalous sediment samples, 40 ppM uranium, came from near Storm King Mountain and upper Vallecito Creek. Other anomalous areas, including the Lake City mining district, were well defined by 4 to 30 ppM uranium in sediment and 3 to 30 ppB uranium in water. Anomalous areas not previously reported indicate favorable areas for future exploration

Study of internal exposure to uranium compounds in fuel fabrication plants in Brazil

International Nuclear Information System (INIS)

Santos, Maristela Souza

2006-01-01

The International Commission on Radiological Protection (ICRP) Publication 66 and Supporting Guidance 3) strongly recommends that specific information on lung retention parameters should be used in preference to default values wherever appropriate, for the derivation of effective doses and for bioassay interpretation of monitoring data. A group of 81 workers exposed to UO 2 at the fuel fabrication facility in Brazil was selected to evaluate the committed effective dose. The workers were monitored for determination of uranium content in the urinary and faecal excretion. The contribution of intakes by ingestion and inhalation were assessed on the basis of the ratios of urinary to fecal excretion. For the selected workers it was concluded that inhalation dominated intake. According to ICRP 66, uranium oxide is classified as insoluble Type S compound. The ICRP Supporting Guidance 3 and some recent studies have recommended specific lung retention parameters to UO 2 . The solubility parameters of the uranium oxide compound handled by the workers at the fuel fabrication facility in Brazil was evaluated on the basis of the ratios of urinary to fecal excretion. Excretion data were corrected for dietary intakes. This paper will discuss the application of lung retention parameters recommended by the ICRP models to these data and also the dependence of the effective committed dose on the lung retention parameters. It will also discuss the problems in the interpretation of monitoring results, when the worker is exposed to several uranium compounds of different solubilities. (author)

Uranium ores

International Nuclear Information System (INIS)

Poty, B.; Roux, J.

1998-01-01

The processing of uranium ores for uranium extraction and concentration is not much different than the processing of other metallic ores. However, thanks to its radioactive property, the prospecting of uranium ores can be performed using geophysical methods. Surface and sub-surface detection methods are a combination of radioactive measurement methods (radium, radon etc..) and classical mining and petroleum prospecting methods. Worldwide uranium prospecting has been more or less active during the last 50 years, but the rise of raw material and energy prices between 1970 and 1980 has incited several countries to develop their nuclear industry in order to diversify their resources and improve their energy independence. The result is a considerable increase of nuclear fuels demand between 1980 and 1990. This paper describes successively: the uranium prospecting methods (direct, indirect and methodology), the uranium deposits (economical definition, uranium ores, and deposits), the exploitation of uranium ores (use of radioactivity, radioprotection, effluents), the worldwide uranium resources (definition of the different categories and present day state of worldwide resources). (J.S.)

Latest data shows long-term security of uranium supply

International Nuclear Information System (INIS)

2010-01-01

Full text: According to Uranium 2009: Resources, Production and Demand just published by the OECD Nuclear En ergy Agency (NEA) and the International Atomic Energy Agency (IAEA), uranium resources, production and demand are all on the rise. Exploration efforts have increased recently in line with the expected expansion of nuclear energy in the coming years. Total identified resources have grown but so too have costs of production. Worldwide exploration and mine development expenditures have more than doubled since the publication of the previous edition, Uranium 2007: Resources, Production and Demand. These expenditures have increased despite declining uranium market prices since mid- 2007. The uranium resources presented in this edition, reflecting the situation as of 1 January 2009, show that total identified resources amounted to 6 306 300 tU, an increase of about 15% compared to 2007, including those reported in the high-cost category (< USD 260/kgU or < USD 100/lbU O), reintroduced for the first time since the 1980s. This high-cost 3 8 category was used in the 2009 edition in response to the generally increased market prices for uranium in recent years, despite the decline since mid-2007, expectations of increasing demand as new nuclear power plants are being planned and built, and increased mining costs. Although total identified resources have increased overall, there has been a significant reduction in lower-cost resources owing to increased mining costs. At 2008 rates of consumption, total identified resources are sufficient for over 100 years of supply. The recognition by an increasing number of governments that nuclear power can produce competitively priced, baseload electricity that is essentially free of greenhouse gas emissions, coupled with the role that nuclear can play in enhancing security of energy supply, increases the prospects for growth in nuclear generating capacity, although the magnitude of that growth remains to be determined. According to

Uranium reserves fall: AAEC

International Nuclear Information System (INIS)

Anon.

1982-01-01

Figures released by the AAEC show that Australia's reasonably assured resources of uranium recoverable at US$80 a kg fell by 5,000 tonnes during 1980-81. Reserves at 30 June 1981 totalled 294,000 tonnes. This represented 17 per cent of the Western World's low cost reasonably assured resources

Metal bioaccumulation, genotoxicity and gene expression in the European wood mouse (Apodemus sylvaticus) inhabiting an abandoned uranium mining area

Energy Technology Data Exchange (ETDEWEB)

Lourenço, Joana, E-mail: joanalourenco@ua.pt [Departamento de Biologia, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); CESAM, Centro de Estudos do Ambiente e do Mar, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Pereira, Ruth [Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CESAM, Centro de Estudos do Ambiente e do Mar, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Gonçalves, Fernando; Mendo, Sónia [Departamento de Biologia, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); CESAM, Centro de Estudos do Ambiente e do Mar, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal)

2013-01-15

Genotoxic effects caused by the exposure to wastes containing metals and radionuclides were investigated in the European wood mice (Apodemus sylvaticus). The animals were captured in the surroundings of an abandoned uranium mining site. DNA damage was assessed by comet assay; gene expression and single nucleotide polymorphisms (SNPs) were assessed, respectively, by Real-Time PCR and melt curve analysis. The bioaccumulation of metals in the liver, kidney and bones was also determined to help clarify cause–effect relationships. Results confirmed the bioaccumulation of cadmium and uranium in organisms exposed to uranium mining wastes. P53 gene was found to be significantly up-regulated in the liver of those organisms and SNPs in the Rb gene were also detected in the kidney. Our results showed that uranium mining wastes caused serious DNA damage resulting in genomic instability, disclosed by the significant increase in DNA strand breaks and P53 gene expression disturbance. These effects can have severe consequences, since they may contribute for the emergence of serious genetic diseases. The fact that mice are often used as bioindicator species for the evaluation of risks of environmental exposure to humans, raises concerns on the risks for human populations living near uranium mining areas. - Highlights: ► Long term effects of chronic pollution in natural population of rodents. ► Bioaccumulation of cadmium and uranium by organisms exposed to uranium wastes. ► P53 upregulation in the liver and SNPs in the Rb gene detected in the kidney. ► Significant DNA damages detected by the comet assay. ► Concerns on the risks of human populations living nearby uranium mining areas.

Water Sorption and Gamma Radiolysis Studies for Uranium Oxides

Energy Technology Data Exchange (ETDEWEB)

Icenhour, A.S.

2002-02-27

During the development of a standard for the safe, long-term storage of {sup 233}U-containing materials, several areas were identified that needed additional experimental studies. These studies were related to the perceived potential for the radiolytic generation of large pressures or explosive concentrations of gases in storage containers. This report documents the results of studies on the sorption of water by various uranium oxides and on the gamma radiolysis of uranium oxides containing various amounts of sorbed moisture. In all of the experiments, {sup 238}U was used as a surrogate for the {sup 233}U. For the water sorption experiments, uranium oxide samples were prepared and exposed to known levels of humidity to establish the water uptake rate. Subsequently, the amount of water removed was studied by heating samples in a oven at fixed temperatures and by thermogravimetric analysis (TGA)/differential thermal analysis (DTA). It was demonstrated that heating at 650 C adequately removes all moisture from the samples. Uranium-238 oxides were irradiated in a {sup 60}Co source and in the high-gamma-radiation fields provided by spent nuclear fuel elements of the High Flux Isotope Reactor. For hydrated samples of UO{sub 3}, H{sub 2} was the primary gas produced; but the total gas pressure increase reached steady value of about 10 psi. This production appears to be a function of the dose and the amount of water present. Oxygen in the hydrated UO{sub 3} sample atmosphere was typically depleted, and no significant pressure rise was observed. Heat treatment of the UO{sub 3} {center_dot} xH{sub 2}O at 650 C would result in conversion to U{sub 3}O{sub 8} and eliminate the H{sub 2} production. For all of the U{sub 3}O{sub 8} samples loaded in air and irradiated with gamma radiation, a pressure decrease was seen and little, if any, H{sub 2} was produced--even for samples with up to 9 wt % moisture content. Hence, these results demonstrated that the efforts to remove trace

Port Radium Canada's Original Radium/Uranium Mine, The Complete Story of Canada's Historic Radium/Uranium Mine, 1932 to 2012 - 13159

International Nuclear Information System (INIS)

Chambers, Doug; Wiatzka, Gerd; Brown, Steve

2013-01-01

This paper provides the life story of Canada's original radium/uranium mine. In addition to the history of operations, it discusses the unique and successful approach used to identify the key issues and concerns associated with the former radium, uranium and silver mining property and the activities undertaken to define the remedial actions and subsequent remedial plan. The Port Radium Mine site, situated approximately 275 km north of Yellowknife on the east shore of Great Bear Lake, Northwest Territories, was discovered in 1930 and underground mining began in 1932. The mine operated almost continuously from 1932 to 1982, initially for recovery of radium, then uranium and finally, for recovery of silver. Tailings production totaled an estimated 900,000 tons and 800,000 tons from uranium and silver processing operations respectively. In the early days of mining, Port Radium miners were exposed to radon and associated decay product levels (in Working Level Months of exposure - WLM) hundreds of times greater than modern standards. The experience of the Port Radium miners provides important contribution to understanding the risks from radon. While the uranium mine was originally decommissioned in the early 1960's, to the standards of the day, the community of Deline (formerly Fort Franklin) had concerns about residual contamination at the mine site and the potential effects arising from use of traditional lands. The Deline people were also concerned about the possible risks to Deline Dene arising from their work as ore carriers. In the late 1990's, the community of Deline brought these concerns to national attention and consequently, the Government of Canada and the community of Deline agreed to move forward in a collaborative manner to address these concerns. The approach agreed to was to establish the Canada-Deline Uranium Table (CDUT) to provide a joint process by which the people of Deline could have their concerns expressed and addressed. A great deal of work was

Uranium analysis in Cypriot groundwaters by total alpha-radiometry and alpha-spectroscopy

International Nuclear Information System (INIS)

Efstathiou, Maria; Kiliari, Tasoula; Pashalidis, Ioannis

2011-01-01

Two different alpha-radiometric methods (e.g. alpha-spectroscopy and alpha-particle counting) have been applied to the determination of uranium in Cypriot groundwater samples after separation of the radionuclides by cation exchange using Chelex-100 and its electrodeposition on stainless steel planchettes. The data obtained were compared to show the advantages and disadvantages of the two radiometric methods, determine the alpha-radioactivity concentration and the radiation dose associated with the use of the studied groundwaters. Calibration of the methods was performed by means of uranium standard solutions and the corresponding data were used to evaluate linear range, detector efficiency, detection limits, value of the information obtained, and time of analysis of the methods. Comparison of the data obtained from calibration and natural sample measurements has shown that alpha-particle counting with a simple alpha-radiometer (equipped with a semiconductor detector) may offer only an activity value and not detailed information about the isotopic composition but it is the fastest method and the method of choice if only a screening method for the alpha-radioactivity measurement is required. Based on the alpha-radioactivity data, the corresponding radiation dose was estimated for situations where the groundwaters are used for drinking water purposes.

Studies on the determination of uranium by potentiometry

International Nuclear Information System (INIS)

Venkataramana, P.; John, Mary; Nair, P.R.; Kasar, U.M.; Natarajan, P.R.

1981-01-01

A potentiometric method for the determination of uranium standardised earlier has been in use for the chemical quality control of plutonium fuels. The method involves the reduction of U(VI) in phosphoric acid medium and titration of U(IV) against Cr(VI). An extension of the range of the quantity of uranium determined by the same method is reported here. The precisions have been evaluated at 13 concentration levels. 20 titrations were carried out at each concentration. the precision at 20 μg level was found to be 3.8% while it was better than 0.03% at concentrations ranging from 20 mg upto 200 mg. At 100 mg and 200 mg of uranium the total volume of the reagent solutions was 50 ml while in other cases it was 25 ml. The effects of a few impurities on the uranium determination were also studied for the 2-5 mg range of uranium. (author)

Granite-related hypothermal uranium mineralization in South China

International Nuclear Information System (INIS)

Liu, X.; Wu, J.; Pan, J.; Zhu, M.

2014-01-01

As one of the important geological types, granite-related uranium deposits account for about 29% of the total discovered natural uranium resources in China. Most of the granite-related uranium deposits located in Taoshan - Zhuguang uranium metallogenic belt, South China. In addition to the typical pitchblende vein-type uranium mineralization of epithermal metallogenic system, a new type of granite-related uranium mineralization with characteristics of hypothermal matallogenic system was discovered in South China by current studies. However, hypothermal is contact thermal to epithermal mineralization, and not the conventional intrusive high temperature mineralization. Hypothermal uranium mineralization is presented by disseminated uraninite or pitchblende stockwork in fissures in granites normally with extensive alkaline alteration. The high temperature mineral assemblage of uraninite associate with scheelite and tourmaline was identified in hypothermal uranium mineralization. Fluid inclusion studies on this type mineralization indicated the middle to high temperature (>250℃) mineralization with the mixing evidence of ore forming solution derived from deep level, and the boiling and mixing of ore forming solution are regarded as the dominant mineralization mechanism for the precipitating of uranium. In contrast to the mineralization ages of 67 Ma to 87 Ma for typical pitchblende vein mineralization of epithermal metallogenic system, the mineralization age is older than 100 Ma for hypothermal uranium mineralization in granite. In the Shituling deposit, Xiazhuang uranium ore field, uraninite and pitchblende micro veins with extensive potassic alteration, chloritization and sericitization are hosted in fissures of Indo-Chinese epoch granites with the uranium mineralization age of 130 Ma to 138 Ma with a mineralization temperature of 290℃ to 330℃ indicated. Other examples sharing the similar characters of hypothermal uranium mineralization have been recognized in

Geological and geochronological evidence for the effect of Paleogene and Miocene uplift of the Northern Ordos Basin on the formation of the Dongsheng uranium district, China

Science.gov (United States)

Zhang, Chuang; Yi, Chao; Dong, Qian; Cai, Yu-Qi; Liu, Hong-Xu

2018-02-01

The Dongsheng uranium district, located in the northern part of the Ordos Basin, contains the largest known sandstone-hosted uranium deposit in China. This district contains (from west to east) the Daying, Nalinggou, and Dongsheng uranium deposits that host tens of thousands of metric tonnes of estimated recoverable uranium resources at an average grade of 0.05% U. These uranium orebodies are generally hosted by the lower member of the Zhiluo Formation and are dominantly roll or tabular in shape. The uranium deposits in this district formed during two stages of mineralization (as evidenced by U-Pb dating) that occurred at 65-60 and 25 Ma. Both stages generated coffinite, pitchblende, anatase, pyrite, and quartz, with or without sericite, chlorite, calcite, fluorite, and hematite. The post-Late Cretaceous uplift of the Northern Ordos Basin exposed the northern margins of the Zhiluo Formation within the Hetao depression at 65-60 Ma, introducing groundwater into the formation and generating the first stage of uranium mineralization. The Oligocene (∼25 Ma) uplift of this northern margin exposed either the entirety of the southern flank of the Hetao depression or only the clastic sedimentary part of this region, causing a second gravitational influx of groundwater into the Zhiluo Formation and forming the second stage of uranium mineralization.

Results of uranium hydrogeochemical and stream sediment reconnaissance of the San Juan area, southwestern Colorado

International Nuclear Information System (INIS)

Maxwell, J.C.

1977-01-01

During June-July 1976, 1706 water samples and 1982 sediment samples were collected from 1995 sites in the San Juan Mountains area and analyzed for uranium. The area includes the southern third of the Colorado mineral belt which has yielded rich ores of gold, silver, copper, lead, zinc, and molybdenum. The broadly domed mountains are capped by 2500 m of Tertiary volcanics, deeply eroded to expose a Precambrian crystalline core. Adjacent plateaus underlain by Mesozoic sedimentary rocks were included in the reconnaissance. Average value of uranium in water samples from mountains was less than 0.5 ppb, from plateaus was 1 to 2 ppb, and from Mancos shale areas exceeded 2 ppb. Anomalous sediment samples, 40 ppM uranium, came from near Storm King Mountain and upper Vallecito Creek. Other anomalous areas, including the Lake City mining district, were well defined by 4 to 30 ppM uranium in sediment and 3 to 30 ppB uranium in water. Above-average concentrations of uranium not previously reported indicate areas favorable for detailed exploration

Uranium abundance in some sudanese phosphate ores

International Nuclear Information System (INIS)

Adam, A.A.; Eltayeb, M.A.H.

2009-01-01

This work was carried out mainly to analysis of some Sudanese phosphate ores, for their uranium abundance and total phosphorus content measured as P 2 O 5 %. For this purpose, 30 samples of two types of phosphate ore from Eastern Nuba Mountains, in Sudan namely, Kurun and Uro areas were examined. In addition, the relationship between uranium and major, and trace elements were obtained, also, the natural radioactivity of the phosphate samples was measured, in order to characterize and differentiate between the two types of phosphate ores. The uranium abundance in Uro phosphate with 20.3% P 2 O 5 is five time higher than in Kurun phosphate with 26.7% P 2 O 5 . The average of uranium content was found to be 56.6 and 310 mg/kg for Kurun and Uro phosphate ore, respectively. The main elements in Kurun and Uro phosphate ore are silicon, aluminum, and phosphorus, while the most abundant trace elements in these two ores are titanium, strontium and barium. Pearson correlation coefficient revealed that uranium in Kurun phosphate shows strong positive correlation with P 2 O 5 , and its distribution is essentially controlled by the variations of P2O5 concentration, whereas uranium in Uro phosphate shows strong positive correlation with strontium, and its distribution is controlled by the variations of Sr concentration. Uranium behaves in different ways in Kurun phosphate and in Uro phosphate. Uro phosphate shows higher concentrations of all the estimated radionuclides than Kurun phosphate. According to the obtained results, it can be concluded that Uro phosphate is consider as secondary uranium source, and is more suitable for uranium recovery, because it has high uranium abundance and low P 2 O 5 %, than Kurun phosphate. (authors) [es

Normalisation of spot urine samples to 24-h collection for assessment of exposure to uranium

International Nuclear Information System (INIS)

Marco, R.; Katorza, E.; Gonen, R.; German, U.; Tshuva, A.; Pelled, O.; Paz-tal, O.; Adout, A.; Karpas, Z.

2008-01-01

For dose assessment of workers at Nuclear Research Center Negev exposed to natural uranium, spot urine samples are analysed and the results are normalised to 24-h urine excretion based on 'standard' man urine volume of 1.6 l d -1 . In the present work, the urine volume, uranium level and creatinine concentration were determined in two or three 24-h urine collections from 133 male workers (319 samples) and 33 female workers (88 samples). Three volunteers provided urine spot samples from each voiding during a 24-h period and a good correlation was found between the relative level of creatinine and uranium in spot samples collected from the same individual. The results show that normalisation of uranium concentration to creatinine in a spot sample represents the 24-h content of uranium better than normalisation to the standard volume and may be used to reduce the uncertainty of dose assessment based on spot samples. (authors)

Unraveling uranium induced oxidative stress related responses in Arabidopsis thaliana seedlings. Part II: responses in the leaves and general conclusions

Energy Technology Data Exchange (ETDEWEB)

Vanhoudt, Nathalie, E-mail: nvanhoud@sckcen.be [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Cuypers, Ann [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Horemans, Nele [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Remans, Tony; Opdenakker, Kelly; Smeets, Karen [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Bello, Daniel Martinez [Hasselt University, Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Agoralaan Building D, 3590 Diepenbeek (Belgium); Havaux, Michel [Commissariat a l' Energie Atomique (CEA)/Cadarache, Direction des Sciences du Vivant, Departement d' Ecophysiologie Vegetale et de Microbiologie, Laboratoire d' Ecophysiologie de la Photosynthese, 13108 Saint-Paul-lez-Durance (France); Wannijn, Jean; Van Hees, May [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Vangronsveld, Jaco [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Vandenhove, Hildegarde [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium)

2011-06-15

The cellular redox balance seems an important modulator under heavy metal stress. While for other heavy metals these processes are well studied, oxidative stress related responses are also known to be triggered under uranium stress but information remains limited. This study aimed to further unravel the mechanisms by which plants respond to uranium stress. Seventeen-day-old Arabidopsis thaliana seedlings, grown on a modified Hoagland solution under controlled conditions, were exposed to 0, 0.1, 1, 10 and 100 {mu}M uranium for 1, 3 and 7 days. While in Part I of this study oxidative stress related responses in the roots were discussed, this second Part II discusses oxidative stress related responses in the leaves and general conclusions drawn from the results of the roots and the leaves will be presented. As several responses were already visible following 1 day exposure, when uranium concentrations in the leaves were negligible, a root-to-shoot signaling system was suggested in which plastids could be important sensing sites. While lipid peroxidation, based on the amount of thiobarbituric acid reactive compounds, was observed after exposure to 100 {mu}M uranium, affecting membrane structure and function, a transient concentration dependent response pattern was visible for lipoxygenase initiated lipid peroxidation. This transient character of uranium stress responses in leaves was emphasized by results of lipoxygenase (LOX2) and antioxidative enzyme transcript levels, enzyme capacities and glutathione concentrations both in time as with concentration. The ascorbate redox balance seemed an important modulator of uranium stress responses in the leaves as in addition to the previous transient responses, the total ascorbate concentration and ascorbate/dehydroascorbate redox balance increased in a concentration and time dependent manner. This could represent either a slow transient response or a stable increase with regard to plant acclimation to uranium stress

Pengaruh Kandungan Uranium Dalam Umpan Terhadap Efisiensi Pengendapan Uranium

OpenAIRE

Torowati

2010-01-01

PENGARUH KANDUNGAN URANIUM DALAM UMPAN TERHADAP EFISIENSI PENGENDAPAN URANIUM. Setiap aktivitas analisis di Laboratorium Kendali Kualitas, Bidang Bahan Bakar Nuklir selalu dihasilkan limbah radioaktif cair. Limbah radioaktif cair di laboratorium masih mengandung uranium yang cukup besar ± 0,600 g U/l dengan keasamaan yang cukup besar pula. Karena uranium mempunyai nilai ekonomis yang cukup tinggi maka perlu USAha untuk mengambil kembali uranium tersebut. Pada kegiatan ini telah dilak...

The problem of radon in uranium mines; Le probleme du radon dans les mines d'uranium

Energy Technology Data Exchange (ETDEWEB)

Jammet, H; Pradel, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

The exploitation of uranium ores constitute the first stage in the use of the atomic energy. With the current methods of exploitation, we meet in these mines various dangers of irradiation and contamination which the presence of the radon constitutes one of the most important aspects. The supportable maximum concentration is currently of 10{sup -10} c of radon by liter of air. It seems, even while considering that the RaA, RaB and RaC descendants are not in balance, that it cannot be fix a less rigorous limit. Indeed the limit proposed by the ''Commission Internationale de Protection Radiologique'' give, for an exhibition of 40 hours per week a dose calculated to the level of the bronchi of: 9,5 rem/week with 100% of RaA and 50% of RaB and RaCs, or 19 rem/week with 100% of RaA, RaB and RaC instead of 0,3 rem. It is necessary, also, to take into account because of the risk is not unique for the miner who is expose to the radiation of ore and breath dusts of uranium. (authors) [French] L'exploitation des minerais d'uranium constitue le premier stade dans l'utilisation de l'energie atomique. Avec les methodes courantes d'exploitation on rencontre dans ces mines des dangers divers d'irradiation et de contamination dont la presence du radon constitue l'un des aspects les plus importants. La concentration maximum tolerable est actuellement de 10{sup -10} c de radon par litre d'air. Il semble, meme en considerant que les descendants RaA, RaB et RaC ne sont pas en equilibre, qu'on ne puisse pas fixer une limite moins rigoureuse. En effet la limite proposee par la Commission Internationale de Protection radiologique donne, pour une exposition de 40 heures par semaine une dose calculee au niveau des bronches de: 9,5 rem/semaine avec 100 % de RaA et 50 % de RaB et RaC, ou 19 rem/semaine avec 100 % de RaA, RaB et RaC au lieu de 0,3 rem. Il faut, en outre, tenir compte du fait que le risque n'est pas unique chez le mineur qui est expose au rayonnement du minerai et respire des

Effects on inhaled uranium mine air contaminants in beagle dogs

International Nuclear Information System (INIS)

Filipy, R.E.; Stuart, B.O.; Palmer, R.F.; Ragan, H.A.; Hackett, P.L.

1974-01-01

The high incidence of lung cancer among uranium miners of the Colorado plateau is a matter of national concern in a period of increasing demand for uranium ore. These miners are exposed to a variety of inhalation hazards, including radon daughters, uranium ore dust, and cigarette smoking, that may cause or contribute to respiratory tract pathology. Over 98 percent of the miners developing lung cancer have had histories of cigarette smoking. In order to determine the combined or separate roles of radon daughters and cigarette smoking in the development of lung cancer and other respiratory tract pathology, groups of 20 dogs each received daily life span exposures to 4 hours of 600 working levels of radon daughters with ore dust, and/or cigarette smoking over 16 hours per day, 7 days per week, or both; control dogs received sham smoking. After 4 years of exposure, respiratory tract pathology included macrophage accumulation, septal fibrosis, epithelial hyperplasia, endothelial proliferation, vesicular and bullous emphysema, and extensive epithelial changes involving squamous metaplasia with atypical nuclei. These effects were primarily related to exposure to radon daughters and uranium ore dust, with and without cigarette smoke

Micronuclei in epithelial cells from sputum of uranium workers

International Nuclear Information System (INIS)

Loomis, D.P.; Shy, C.M.; Allen, J.W.; Saccomanno, G.

1990-01-01

The exfoliated-cell micronucleus (MN) assay was used to assess cytogenetic effects of exposure to radon progeny and cigarette smoke among 99 Colorado plateau uranium workers. Subjects were selected at random from employees in underground and open-pit uranium mines, ore mills, laboratories, and offices participating in a sputum screening program from 1964-88. The prevalence of cells with MN was determined by scoring one sputum specimen for each worker. Data obtained by interview were used to classify exposure to radon progeny and smoking at the time sputum specimens were taken. Underground miners were considered exposed to radon progeny, and others were considered unexposed. Neither radon progeny exposure nor cigarette smoking had any appreciable effect on the prevalence of cells with MN; crude prevalence ratios were 1.0 (95% CI 0.7-1.4) and 0.9 (95% CE 0.6-1.3), respectively. The effects of radon and smoking were not confounded by each other or by age, and there was no evidence of synergy between exposures. The findings appear to cast doubt on the epidemiological utility of a sputum-based MN assay for studies of other populations exposed to occupational or environmental lung carcinogens

Inhalation of uranium nanoparticles: respiratory tract deposition and translocation to secondary target organs in rats.

Science.gov (United States)

Petitot, Fabrice; Lestaevel, Philippe; Tourlonias, Elie; Mazzucco, Charline; Jacquinot, Sébastien; Dhieux, Bernadette; Delissen, Olivia; Tournier, Benjamin B; Gensdarmes, François; Beaunier, Patricia; Dublineau, Isabelle

2013-03-13

Uranium nanoparticles (fuel cycle and during remediation and decommissioning of nuclear facilities. Explosions and fires in nuclear reactors and the use of ammunition containing depleted uranium can also produce such aerosols. The risk of accidental inhalation of uranium nanoparticles by nuclear workers, military personnel or civilian populations must therefore be taken into account. In order to address this issue, the absorption rate of inhaled uranium nanoparticles needs to be characterised experimentally. For this purpose, rats were exposed to an aerosol containing 10⁷ particles of uranium per cm³ (CMD=38 nm) for 1h in a nose-only inhalation exposure system. Uranium concentrations deposited in the respiratory tract, blood, brain, skeleton and kidneys were determined by ICP-MS. Twenty-seven percent of the inhaled mass of uranium nanoparticles was deposited in the respiratory tract. One-fifth of UO₂ nanoparticles were rapidly cleared from lung (T(½)=2.4 h) and translocated to extrathoracic organs. However, the majority of the particles were cleared slowly (T(½)=141.5 d). Future long-term experimental studies concerning uranium nanoparticles should focus on the potential lung toxicity of the large fraction of particles cleared slowly from the respiratory tract after inhalation exposure. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Glances on uranium. From uranium in the earth to electric power

International Nuclear Information System (INIS)

Valsardieu, C.

1995-01-01

This book is a technical, scientific and historical analysis of the nuclear fuel cycle from the origin of uranium in the earth and the exploitation of uranium ores to the ultimate storage of radioactive wastes. It comprises 6 chapters dealing with: 1) the different steps of uranium history (discovery, history of uranium chemistry, the radium era, the physicists and the structure of matter, the military uses, the nuclear power, the uranium industry and economics), 2) the uranium in nature (nuclear structure, physical-chemical properties, radioactivity, ores, resources, cycle, deposits), 3) the sidelights on uranium history (mining, prospecting, experience, ore processing, resources, reserves, costs), 4) the uranium in the fuel cycle, energy source and industrial product (fuel cycle, fission, refining, enrichment, fuel processing and reprocessing, nuclear reactors, wastes management), 5) the other energies in competition and the uranium market (other uranium uses, fossil fuels and renewable energies, uranium market), and 6) the future of uranium (forecasting, ecology, economics). (J.S.)

Translocation of uranium from water to foodstuff while cooking

Energy Technology Data Exchange (ETDEWEB)

Krishnapriya, K.C.; Baksi, Ananya; Chaudhari, Swathi; Gupta, Soujit Sen; Pradeep, T.

2015-10-30

Highlights: • Rice can efficiently uptake uranium from water contaminated with uranyl nitrate hexahydrate (UO{sub 2}(NO{sub 3}) 2.6 H{sub 2}O), while cooking. • Unusual uranium uptake to the extent of about 1000 ppm is observed when rice is cooked in highly concentrated uranium contaminated water (1240 ppm). • Nature of interaction of uranium with carbohydrates is probed using small monosaccharides like glucose and mannose. • Electrospray ionization mass spectrometry showed UO{sub 2}{sup 2+} to be the most stable species in water in such solutions which can form complexes with sugars. • The species (UO{sub 2}{sup 2+}) is also observed in the case of water exposed to the common mineral, uranium oxide (UO{sub 2}) and similar type of complexation is observed with sugars. - Abstract: The present work report the unusual uranium uptake by foodstuff, especially those rich in carbohydrates like rice when they are cooked in water, contaminated with uranium. The major staple diet in South Asia, rice, was chosen to study its interaction with UO{sub 2}{sup 2+}, the active uranium species in water, using inductively coupled plasma mass spectrometry. Highest uptake limit was checked by cooking rice at very high uranium concentration and it was found to be good scavenger of uranium. To gain insight into the mechanism of uptake, direct interaction of UO{sub 2}{sup 2+} with monosaccharides was also studied, using electrospray ionization mass spectrometry taking mannose as a model. The studies have been done with dissolved uranium salt, uranyl nitrate hexahydrate (UO{sub 2}(NO{sub 3}){sub 2}·6H{sub 2}O), as well as the leachate of a stable oxide of uranium, UO{sub 2}(s), both of which exist as UO{sub 2}{sup 2+} in water. Among the eight different rice varieties investigated, Karnataka Ponni showed the maximum uranium uptake whereas unpolished Basmati rice showed the minimum. Interaction with other foodstuffs (potato, carrot, peas, kidney beans and lentils) with and

Uranium prospecting in Cerro Partido Region-Encruzilhada do Sul Basin-RS, Brazil

International Nuclear Information System (INIS)

Fraenkel, M.O.

1974-01-01

The Cerro Partido residual basin is a shallow (85 meters) and small (25km 2 ) sedimentary basin, a remainder of the erosive cicle, enclosed in the pre-cambrian granitic rocks of the Rio Grande do Sul Shield. Grades of 0.2 + U 3 O 8 were found in its upper-paleozoic sandstones and shales drilles for uranium. The small size and thicknesses of these concentrations prevent their economic mining. However, the different levels of the shield exposed by tectonics, the intrusive granitic, riolitic and syenitic rocks, the anomalous uranium contents in sedimentary and crystalline rocks recommend further investigations on the shield area

Corrosion behavior, mechanical properties, and long-term aging of nickel-plated uranium

International Nuclear Information System (INIS)

Dini, J.W.; Johnson, H.R.; Schoenfelder, C.W.

1976-01-01

The behavior of nickel-plated uranium upon exposure to moist nitrogen was evaluated. Plating thicknesses of 0.051 mm (2 mil) were adequate to prevent corrosion. Specimens with thinner coats showed some corrosion and some reduction in mechanical properties during subsequent testing. Plated samples exposed to dry air at ambient pressure for 10 y showed no corrosion and no degradation of mechanical properties. Surface and bulk hydrogen content, as well as free hydrogen generated during the test, were measured to determine the extent of corrosion. Results support an earlier proposed mechanism for uranium corrosion at low humidities

Reconnaissance study of the uranium and thorium contents of plutonic rocks of the southwestern Seward Peninsula, Alaska

International Nuclear Information System (INIS)

Miller, T.P.; Bunker, C.M.

1976-01-01

Large granitic Cretaceous plutons are exposed along and adjacent to an arcuate belt of igneous and high-grade metamorphic rocks in the southeastern Seward Peninsula of Alaska. Reconnaissance studies of these plutons have shown that the Darby pluton has well above average amounts of uranium and thorium (11.2 ppm and 58.7 ppm, respectively), the Kachauik pluton contains average to above average uranium and thorium (5.7 ppm and 22.5 ppm, respectively), and the Bendeleben pluton contains average amounts of uranium and thorium (3.4 ppm and 16.7 ppm, respectively). The three plutons show compositional and textural differences indicative of different source materials that may have controlled the distribution of uranium and thorium. The high uranium and thorium contents of the Darby pluton, similar to those of the Conway Granite of New Hampshire which has been mentioned as a possible low-grade thorium resource, suggest that this pluton may be a favorable area for economic concentrations of uranium and thorium

Survey of United States uranium marketing activity

International Nuclear Information System (INIS)

Krusiewski, S.V.; Thomas, D.C.; Patterson, J.A.

1981-06-01

In 1980 US buyers contracted for 12,500 short tons U 3 O 8 in new procurement. Nontheless, there was a net decrease of 13,100 tons in total commitments as of January 1, 1981, because of even larger changes to the delivery commitments as of January 1, 1980. The average contract price of domestic uranium was $28.15 per pound of U 3 O 8 for 1980 delivery and $30.70 for 1981 delivery. Settlements of domestic market price contracts averaged $36.75 for 1980 delivery and $46.80 for 1981 delivery. Prices of foreign uranium averaged $43.10 for 1980 delivery and $40.00 for 1981 delivery. Producers expect to be able to offer 21,800 tons U 3 O 8 for sale in the 1981 to 1985 period, about 30 percent less than was estimated in the 1980 survey. US producers also estimated that 30,600 tons U 3 O 8 would be available for sale in the 1986 to 1990 period. Utilities made sales of 800 tons U 3 O 8 for 1980 to 1981 delivery as well as loans of another 800 tons. New export commitments made in 1980 totalled 4000 tons U 3 O 8 ; however, 2500 tons of these commitments are options or delivery is contingent on price developments. Import commitments made in 1980 totalled 2300 tons U 3 O 8 . Inventories of natural and enriched uranium held by US buyers increased from 52,300 to 63,400 tons U 3 O 8 during 1980. In addition, inventories of uranium held by US producers increased from 2400 to 2700 tons U 3 O 8 . Unfilled requirements for the 1981 to 1990 period decreased from 75,300 tons U 3 O 8 , as reported in last year's survey, to 54,500 tons in this year's survey, a decrease of 20,800 tons. Responses to the 1981 survey suggest that there seems to be an adequate supply of uranium to meet US demand at least through 1986, although the apparent buyer requirements reported as of January 1, 1981 for the 1987 to 1990 period are higher than the total domestic production or supply

The determination of total cyanide in solutions containing uranium and gold

International Nuclear Information System (INIS)

Solomons, M.; Dixon, K.

1983-01-01

This report gives the results of a limited investigation of three distillation procedures and their variants for the separation of cyanide. The spectrophotometric measurement, which follows the distillation, uses either a mixture of pyridine and pyrazolone, or a mixture of pyridine and barbituric acid. It was found that the method published in the South Africa Government Gazette in 1969 gives quantitative recoveries from potassium cyanide solutions but not in the presence of gold. The ligand-displacement method did not give quantitative recoveries in the presence of gold, except when zinc was added to the distilland, and it then failed to give a quantitative recovery of cyanide from ferrocyanide. These two methods were therefore rejected as unsuitable for the determination of cyanide in solutions containing small amounts of uranium and gold. The procedure of the American Public Health Association (APHA) was found to give quantitative recoveries in the presence of gold, uranium, thiocyanate, and ferrocyanide when cuprous chloride, or cuprous chloride with magnesium chloride, are added to the distilland. The spectrophotometric measurement using a mixture of pyridine and barbituric acid is preferred. The calibration range of the method is 0,5 to 6μg of cyanide, and the limit of determination is 0,04μg/cm 3 . (The relative standard deviation of the method is 0,05.) The distillation time in the APHA method is approximately two and a half hours; with 3 distillation trains, up to 9 distillations can be made per day, plus a further 2 hours for the spectrophotometric determination. The preferred laboratory method is detailed in an appendix

Semi-detailed uranium geochemical survey in Northwestern Samar (27 March 1979 - 4 July 1979)

International Nuclear Information System (INIS)

Santos, G. Jr.; Ogena, M.; Tauli, G.

1980-04-01

A uranium geochemical survey was conducted to delineate in detail the uranium prospective area(s) in northwestern Samar. A total of 805 stream sediments and 1.115 water samples were obtained from the target areas from uranium analysis. Geochemical anomalies were indicated in San Isidro and Mauo. Geochemical correlations between uranium and trace elements (Pb, Ag, Ni, Cu, Co, Zn and Mn) were generally poor. (ELC)

Effect of uranium on growth and reproduction of the marine amphipod Allorchestes compressa

International Nuclear Information System (INIS)

Ahsanullah, M.; Williams, A.R.

1986-01-01

Experiments on growth of the marine amphipod Allorchestes compressa Dana were carried out over four weeks, and both growth and reproduction were studied over three generations, each of which was exposed to uranium for approximately 10 wk. At 0.1 mg l -1 the uranium increased growth by 23%, as measured by the mean weight after 4 wk, and at 2 mg l -1 growth was reduced by 28% compared with the control. A. compressa accumulated uranium from sea water with a concentration factor of 10. There was no effect of uranium on the survival of amphipods or their progeny in the multiple-generation experiment, but the numbers of males, the sex ratio, and the respiration rate (measured on males only) at 1 mg l -1 were significantly lower than the control. A. compressa is shown to be a convenient species for the study of toxic effects on growth and reproduction using multiple-generation experiments. (orig.)

Uranium prospecting; La prospection de l'uranium

Energy Technology Data Exchange (ETDEWEB)

Roubault, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

This report is an instruction book for uranium prospecting. It appeals to private prospecting. As prospecting is now a scientific and technical research, it cannot be done without preliminary studies. First of all, general prospecting methods are given with a recall of fundamental geologic data and some general principles which are common with all type of prospecting. The peculiarities of uranium prospecting are also presented and in particular the radioactivity property of uranium as well as the special aspect of uranium ores and the aspect of neighbouring ores. In a third part, a description of the different uranium ores is given and separated in two different categories: primary and secondary ores, according to the place of transformation, deep or near the crust surface respectively. In the first category, the primary ores include pitchblende, thorianite and rare uranium oxides as euxenite and fergusonite for example. In the second category, the secondary ores contain autunite and chalcolite for example. An exhaustive presentation of the geiger-Mueller counter is given with the presentation of its different components, its functioning and utilization and its maintenance. The radioactivity interpretation method is showed as well as the elaboration of a topographic map of the measured radioactivity. A brief presentation of other detection methods than geiger-Mueller counters is given: the measurement of fluorescence and a chemical test using the fluorescence properties of uranium salts. Finally, the main characteristics of uranium deposits are discussed. (M.P.)

Study on the radiotoxicology of enriched uranium

International Nuclear Information System (INIS)

Zhu Shoupeng; Zheng Siying; Wang Guolin; Wang Chongdao; Cao Genfa

1987-12-01

A study on the retentive peculiarity of soluble enriched uranium UO 2 F 2 were observed after iv once or consecutive ip qd x 3d to Wistar male rats. The dynamic retention of radioactivity in the body showed that the enriched uranium UO 2 F 2 was chiefly localized in kidney, and then in skeleton and liver. The radioactivity of the enriched uranium UO 2 F 2 in skeleton rose steadily while the concentratoin in kidney and liver droped. When enriched uranium UO 2 F 2 was accumulated in organism, it caused chromosome aberrations on bone marrow cells. Results indicated that the chromosome aberration rates were elevated when the dose of the enriched uranium UO 2 F 2 was increased, at the same time, the cell division was depressed. Accumulation of insoluble enriched uranium U 3 O 8 in gastrointestinal tract was well described by a two exponential expression. Values of retention estimate for fast component, T 1 = 0.34 d, and for relatively long term component, T 2 = 4.05 d. The deposition of UO 2 F 2 in the intact skin was only 0.16 to 0.18% of the total contaminated UO 2 F 2 . Penetration of the enriched uranium UO 2 F 2 was dominantly increased in abraded skin. This value is about 25 to 32 times as compaired with that in intact skin. Retention of the enriched uranium UO 2 F 2 through abraded skins was dominantly localized in kidney and skeleton

The solubility of uranium trioxide simulated lung fluid

International Nuclear Information System (INIS)

Kravchiks, T.; Kol, R.; Prager, A.; German, U.; Oved, S.; Laichter, Y.

1997-01-01

Uranium trioxide is an important intermediate compound in the uranium production process. Inhalation of UO 3 aerosols can occur during this process. To assess the radiation dose from the intake of this compound it is necessary to know its transportability class, based on its dissolution rate in lung fluid. The International Commission on Radiological Protection (ICRP) has assigned UO 3 to Inhalation Class W (lung retention half-time of 10 to 100 days). A solubility study of UO 3 in a simulated lung fluid has been carried out using a batch/filter replacement method. Two tests were conducted over a 100-days period, during which 17 samples were collected and analyzed for their dissolved uranium content. The results show that about 40% of the total uranium was dissolved during the first days and nearly all was dissolved during 100 days. Expressed as the fraction of the total uranium remaining undissolved as a function of time, using a non-linear least squares regression fit, it was found that the solubility of UO 3 in simulated lung fluid could be expressed as a combination of two Inactions: about 25% of the UO 3 could be classified as type D (with lung retention half-time of several hours) and about 75% as type W (with half-time of 10-20 days). This classification is in agreement with recent investigations and indicates that UO 3 is more soluble than considered by ICRP. (authors)

Uncertainty hovers over the uranium market

International Nuclear Information System (INIS)

Holtorp, J.

1981-01-01

The results of evaluation of capitalist countries requirements for uranium for nuclear power engineering in 1985-1995 are presented. The data of maximum and minimum forecasting of NPP construction have been taken into account. It is assumed that the NPP total power in capitalist countries is to attain by 1990 335-350 million kW and by 1995 356-549 million kW. It is pointed out that by 1990 uranium production will constitute 82 thousand a year: 45% of this amount will be produced at existing mines, 17% at mines under construction and 38% at the designed mines. Use of only operating mines will enable in 1985 to have reserves of produced uranium sufficient for meeting the requirements of nuclear power engineering during 2.2 years and in 1990 - 0.7 year. On the basis of analysis of the given data the conclusion is drawn that uranium requirements in the nearest future will not be great, particularly if the observed decrease in the NPPs construction scale growth rate is preserved [ru

Uranium

International Nuclear Information System (INIS)

Stewart, E.D.J.

1974-01-01

A discussion is given of uranium as an energy source in The Australian economy. Figures and predictions are presented on the world supply-demand position and also figures are given on the added value that can be achieved by the processing of uranium. Conclusions are drawn about Australia's future policy with regard to uranium (R.L.)

Nuclear forensic analysis of uranium oxide powders interdicted in Victoria, Australia

Energy Technology Data Exchange (ETDEWEB)

Kristo, Michael Joseph [Lawrence Livermore National Laboratory, Livermore, CA (United States); Keegan, Elizabeth; Colella, Michael [Australian Nuclear Science and Technology Organisation, Kirrawee, NSW (Australia); and others

2015-07-01

Nuclear forensic analysis was conducted on two uranium samples confiscated during a police investigation in Victoria, Australia. The first sample, designated NSR-F-270409-1, was a depleted uranium powder of moderate purity (∝ 1000 μg/g total elemental impurities). The chemical form of the uranium was a compound similar to K{sub 2}(UO{sub 2}){sub 3}O{sub 4} . 4H{sub 2}O. While aliquoting NSR-F-270409-1 for analysis, the body and head of a Tineid moth was discovered in the sample. The second sample, designated NSR-F-270409-2, was also a depleted uranium powder. It was of reasonably high purity (∝ 380 μg/g total elemental impurities). The chemical form of the uranium was primarily UO{sub 3} . 2H{sub 2}O, with minor phases of U{sub 3}O{sub 8} and UO{sub 2}. While aliquoting NSR-F-270409-2 for analysis, a metal staple of unknown origin was discovered in the sample. The presence of {sup 236}U and {sup 232}U in both samples indicates that the uranium feed stocks for these samples experienced a neutron flux at some point in their history. The reactor burn-up calculated from the isotopic composition of the uranium is consistent with that of spent fuel from natural uranium (NU) fueled Pu production. These nuclear forensic conclusions allow us to categorically exclude Australia as the origin of the material and greatly reduce the number of candidate sources.

Determination of natural and depleted uranium in urine at the ppt level: an interlaboratory analytical exercise

International Nuclear Information System (INIS)

D'Agostino, P.A.; Ough, E.A.; Glover, S.E.; Vallerand, A.L.

2002-10-01

An analytical exercise was initiated in order to determine those analytical procedures with the capacity to measure uranium isotope ratios ( 238 U/ 235 U) in urine samples containing less that 1μ uranium /L urine. A host laboratory was tasked with the preparation of six sets (12 samples per set) of synthetic urine samples spiked with varying amounts of natural and depleted (0.2% 235 U) uranium. The sets of samples contained total uranium in the range 25 ng U/L urine to 770 ng U/L urine, with isotope ratios ( 238 U/ 235 U) from 137.9 (natural uranium) to 215 (∼50% depleted uranium). Sets of samples were shipped to five testing laboratories (four Canadian and one European) for total and isotopic assay. The techniques employed in the analyses included sector field inductively coupled plasma mass spectrometry (ICP-SF-MS), quadrupole inductively coupled plasma mass spectrometry (ICP-Q-MS), thermal ionization mass spectrometry (TIMS) and neutron activation analysis (NAA). Full results were obtained from three testing labs (ICP-SF-MS, ICP-Q-MS and TIMS). Their results, plus partial results from the NAA lab, have been included in this report. Total uranium and isotope ratio results obtained from ICP-SF-MS and ICP-Q-MS were in good agreement with the host lab values. Neutron activation analysis and TIMS reported total uranium concentrations that differed from the host lab. An incomplete set of isotopic ratios was obtained from the NAA lab with some results reporting enriched uranium (% 235 U > 0.7). Based on the reported results, the four analytical procedures were ranked: ICP-SF-MS (1), ICP-Q-MS (2), TIMS (3) and NAA (4). (author)

Uranium, depleted uranium, biological effects

International Nuclear Information System (INIS)

2001-01-01

Physicists, chemists and biologists at the CEA are developing scientific programs on the properties and uses of ionizing radiation. Since the CEA was created in 1945, a great deal of research has been carried out on the properties of natural, enriched and depleted uranium in cooperation with university laboratories and CNRS. There is a great deal of available data about uranium; thousands of analyses have been published in international reviews over more than 40 years. This presentation on uranium is a very brief summary of all these studies. (author)

Recovery of uranium from phosphatic rock and its derivatives

International Nuclear Information System (INIS)

Romero Guzman, E.T.

1992-01-01

The recovery of uranium present in the manufacture process of phosphoric acid and fertilizers has been one interesting field of study in chemistry. It is true that the recovery of uranium it is not very attractive from the commercial point of view, however the phosphatic fertilizers have an important amount of uranium which comes from the starting materials (phosphatic rock), therefore there must be many tons of uranium that are dispersed in the environmental together with the fertilizers used in agriculture every year. They are utilized for the enrichment of the nutrients which are exhausted in the soil. In this work, uranium was identified and quantified in the phosphatic rocks and in inorganic fertilizers using Gamma Spectroscopy, Neutron Activation Analysis, UV/Visible Spectrophotometry, Alpha Spectroscopy. On the other hand, it was done a correlation of the behaviour of uranium with inorganic elements present in the samples such as phosphorus, calcium and iron; which were determined by UV/Visible Spectrophotometry for phosphorus and Atomic Absorption Spectrometry for calcium and iron. The quantity of uranium found in the phosphatic rock, phosphoric acid and fertilizers was considerable (70-200 ppm). The adequate conditions for the recovery of 40% of total of uranium from the phosphatic rock with the addition of leaching solutions were stablished. (Author)

Manual on laboratory testing for uranium ore processing

International Nuclear Information System (INIS)

1990-01-01

Laboratory testing of uranium ores is an essential step in the economic evaluation of uranium occurrences and in the development of a project for the production of uranium concentrates. Although these tests represent only a small proportion of the total cost of a project, their proper planning, execution and interpretation are of crucial importance. The main purposes of this manual are to discuss the objectives of metallurgical laboratory ore testing, to show the specific role of these tests in the development of a project, and to provide practical instructions for performing the tests and for interpreting their results. Guidelines on the design of a metallurgical laboratory, on the equipment required to perform the tests and on laboratory safety are also given. This manual is part of a series of Technical Reports on uranium ore processing being prepared by the IAEA's Division of Nuclear Fuel Cycle and Waste Management. A report on the Significance of Mineralogy in the Development of Flowsheets for Processing Uranium Ores (Technical Reports Series No. 196, 1980) and an instruction manual on Methods for the Estimation of Uranium Ore Reserves (No. 255, 1985) have already been published. 17 refs, 40 figs, 17 tabs

Uranium complex recycling method of purifying uranium liquors

International Nuclear Information System (INIS)

Elikan, L.; Lyon, W.L.; Sundar, P.S.

1976-01-01

Uranium is separated from contaminating cations in an aqueous liquor containing uranyl ions. The liquor is mixed with sufficient recycled uranium complex to raise the weight ratio of uranium to said cations preferably to at least about three. The liquor is then extracted with at least enough non-interfering, water-immiscible, organic solvent to theoretically extract about all of the uranium in the liquor. The organic solvent contains a reagent which reacts with the uranyl ions to form a complex soluble in the solvent. If the aqueous liquor is acidic, the organic solvent is then scrubbed with water. The organic solvent is stripped with a solution containing at least enough ammonium carbonate to precipitate the uranium complex. A portion of the uranium complex is recycled and the remainder can be collected and calcined to produce U 3 O 8 or UO 2

Contractual arrangements for uranium exploration and mining

International Nuclear Information System (INIS)

1988-07-01

Uranium exploration in WOCA, stabilized since 1985 at a level of annual expenditures of US $120-150 million. About half of this amount is funded by mining companies based in the uranium consumer countries such as the Federal Republic of Germany, France, the Republic of Korea, Japan, United Kingdom etc. and expended outside their home countries, mainly in Australia, Canada and USA, but also in a number of African countries. As WOCA's uranium production is concentrated in a few countries, in 1986, Australia, Canada, South Africa and USA had a combined share of nearly 70% of the total, a stronger diversification of uranium supplies may be desirable in the future. This expected trend may result in the planning or uranium exploration projects by international uranium companies in countries in Africa, Asia and South America. To provide information which can be helpful for both parties in the negotiations of cooperation agreement is the scope of this document. It contains a brief introductory part including an overview of the development of the different forms of international cooperation, a case history provided by Zambia, a report listing the essential subjects to be included in an uranium agreement as well as an example of a structure of contractual arrangements. This part is followed by an extensive annex with three ''no-names-no numbers'' contract texts, which were concluded in the later part of the 1970s and beginning of the 1980s

Uranium bioprecipitation mediated by yeasts utilizing organic phosphorus substrates.

Science.gov (United States)

Liang, Xinjin; Csetenyi, Laszlo; Gadd, Geoffrey Michael

2016-06-01

In this research, we have demonstrated the ability of several yeast species to mediate U(VI) biomineralization through uranium phosphate biomineral formation when utilizing an organic source of phosphorus (glycerol 2-phosphate disodium salt hydrate (C3H7Na2O6P·xH2O (G2P)) or phytic acid sodium salt hydrate (C6H18O24P6·xNa(+)·yH2O (PyA))) in the presence of soluble UO2(NO3)2. The formation of meta-ankoleite (K2(UO2)2(PO4)2·6(H2O)), chernikovite ((H3O)2(UO2)2(PO4)2·6(H2O)), bassetite (Fe(++)(UO2)2(PO4)2·8(H2O)), and uramphite ((NH4)(UO2)(PO4)·3(H2O)) on cell surfaces was confirmed by X-ray diffraction in yeasts grown in a defined liquid medium amended with uranium and an organic phosphorus source, as well as in yeasts pre-grown in organic phosphorus-containing media and then subsequently exposed to UO2(NO3)2. The resulting minerals depended on the yeast species as well as physico-chemical conditions. The results obtained in this study demonstrate that phosphatase-mediated uranium biomineralization can occur in yeasts supplied with an organic phosphate substrate as sole source of phosphorus. Further understanding of yeast interactions with uranium may be relevant to development of potential treatment methods for uranium waste and utilization of organic phosphate sources and for prediction of microbial impacts on the fate of uranium in the environment.

Incorporation of Uranium into Hematite during Crystallization from Ferrihydrite

Science.gov (United States)

2014-01-01

Ferrihydrite was exposed to U(VI)-containing cement leachate (pH 10.5) and aged to induce crystallization of hematite. A combination of chemical extractions, TEM, and XAS techniques provided the first evidence that adsorbed U(VI) (≈3000 ppm) was incorporated into hematite during ferrihydrite aggregation and the early stages of crystallization, with continued uptake occurring during hematite ripening. Analysis of EXAFS and XANES data indicated that the U(VI) was incorporated into a distorted, octahedrally coordinated site replacing Fe(III). Fitting of the EXAFS showed the uranyl bonds lengthened from 1.81 to 1.87 Å, in contrast to previous studies that have suggested that the uranyl bond is lost altogether upon incorporation into hematite. The results of this study both provide a new mechanistic understanding of uranium incorporation into hematite and define the nature of the bonding environment of uranium within the mineral structure. Immobilization of U(VI) by incorporation into hematite has clear and important implications for limiting uranium migration in natural and engineered environments. PMID:24580024

Preparation and certification of a reference uranium

International Nuclear Information System (INIS)

Anon.

1979-06-01

The CEA Analysis Coordination has produced a reference uranium metal of guaranteed minimum uranium content. The metal was purified by electro-refining in fused salt baths and the dendrites obtained were cast in the form of an ingot by electron bombardment. The ingot was rolled and cut into pieces of mass between 0.5 g and 1.5 g, and each piece conditioned in a glass ampoule under primary vacuum. The total number of reference samples is about 4500. The uranium content was inferred from the impurity concentration determined by spark mass spectrometry and atomic or molecular adsorption spectrophotometry and from the gas concentration determined by specific methods. A certificate of guarantee gives instructions for the use of these reference samples [fr

Development of uranium industry in Romania

International Nuclear Information System (INIS)

Iuhas, Tiberiu

2000-01-01

The management of the uranium resources is performed in Romania by the National Uranium Company. The tasks to be done are: 1. management and protection of rare and radioactive metal ores in the exploitation areas; 2. mining, preparation, refining and trading the radioactive ores, as well as reprocessing the uranium stock from the uranium concentrate in the national reserve; 3. performing geologic and technologic studies in the exploitation areas; 4. performing studies and projects concerning the maintenance of the present facilities and unearthing new ores; 5. building industrial facilities; 6. carrying out technological transport; 7. importation-exportation operations; 8. performing micro-production activity in experimental research units; 9. personnel training; 10. medical assistance for the personnel; 11. environment protection. The company is organized as follows: 1.three branches for uranium ore mining, located at Suceava, Bihor and Banat; 2. one branch for geologic survey, located at Magurele; 3. one branch for uranium ore preparation and concentration and for refining uranium concentrates, located at Feldioara; 4. One group for mine conservation, closure and ecology, located at Bucuresti. The final product, sintered powder of UO 2 produced at Feldioara plant, was tested in 1994 by the Canadian partner and met successfully the required standards. The Feldioara plant was certified as supplier of raw material for CANDU nuclear fuel production and as such, Romania is the only authorized producer of CANDU nuclear fuel in Europe and the second in the world, after Canada. Maintaining the uranium production in Romania is justified by the existence of uranium ore resources, the declining of natural gas resources, lower costs per kWh for electric nuclear power as compared to fossil-fuel power production, the possibility for Romania to become an important supplier of CANDU nuclear fuel, the low environmental impact and high costs for total shutdown of activity, high

The Development of Low-Level Measurement Capabilities for Total and Isotopic Uranium in Environmental Samples at Brazilian and Argentine Laboratories by ABACC

International Nuclear Information System (INIS)

Guidicini, Olga M.; Olsen, Khris B.; Hembree, Doyle M.; Carter, Joel A.; Whitaker, Michael; Hayes, Susan M.

2005-01-01

In June 1998, the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC), with assistance from the U.S. Department of Energy (DOE), began a program to assess environmental sampling and analysis capabilities at laboratories in Argentina and Brazil. The program began with staff training conducted in South America and the United States by Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL). Both laboratories are participating members of DOE's Network of Analytical Laboratories (NWAL) that support IAEA's environmental sampling program. During the initial planning meeting, representatives from ABACC and all the participating analytical laboratories supporting ABACC were briefed on how the first exercise would be managed and on key aspects necessary to analyze low-level environmental samples for uranium. Subsequent to this training, a laboratory evaluation exercise (Exercise 1) was conducted using standard swipe samples prepared for this exercise by the International Atomic Energy Agency (IAEA). The results of Exercise 1 determined that sample contamination was a major factor in the analysis, and a thorough review of laboratory procedures was required to reduce the level of contamination to acceptable levels. Following modification of sample preparation procedures, the laboratories performed Exercise 2, an analysis of a National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 1547, Peach Leaves. The results of Exercise 2 demonstrated that several laboratories were capable of accurately determining the total uranium and uranium isotopic distribution in the peach leaves. To build on these successes, Exercise 3 was performed using a series of standard swipe samples prepared by the IAEA and distributed to laboratories supporting ABACC and to PNNL and ORNL. The results of Exercise 3 demonstrate that ABACC now has support laboratories in both Argentina and Brazil, which are capable of

Uranium

International Nuclear Information System (INIS)

Toens, P.D.

1981-03-01

The geological setting of uranium resources in the world can be divided in two basic categories of resources and are defined as reasonably assured resources, estimated additional resources and speculative resources. Tables are given to illustrate these definitions. The increasing world production of uranium despite the cutback in the nuclear industry and the uranium requirements of the future concluded these lecture notes

Toward harmonious development of the uranium market

International Nuclear Information System (INIS)

Suzuki, Y.

1984-01-01

Japan's economy is in a period of low growth, and growth in electricity demand has decreased substantially. Nuclear power remains the mainstay of Japan's energy policy, even though targets have been lowered. Japanese utilities attempted to procure as much uranium as possible for the long-term operation of their plants soon after the nuclear development plan was set in 1972. By 1975 they had secured around 80% of the cumulative uranium requirements up to the year 1990 through long-term contracts. Since then the scale of the nuclear power development program has shrunk to about one third of what it was in 1975. As a result, the quantity of uranium under long-term contracts far exceeds the actual demand. The existing contracted quantity is sufficient to cover total demand well into the late 1990s. Appropriate levels of stockpiling have yet to be determined. Security of supply can be assured without stockpiling if utilities diversify their sources of supply. The uranium market will develop harmoniously if producers and suppliers work towards securing flexibility for demand fluctuations, preventing government interference, and exchanging the information needed for precise uranium demand forecasting. (L.L.)