A survey of uranium levels in urine and hair of people living in a coal mining area in Yili, Xinjiang, China.

Recent reports have drawn attention to the uranium contamination arising from coal mining activities in the Yili region of Xinjiang, China due to the mixed distribution of uranium and coal mines, and some of the coal mines being associated with a high uranium content. In this study, we have collected water samples, solid samples such as soil, mud, coal, and coal ash, and hair and urine samples from local populations in order to evaluate the uranium level in this environment and its implications for humans in this high uranium coal mining area. Our results showed that uranium concentrations were 8.71-10.91 µg L-1 in underground water, whereas lower levels of uranium occurred in river water. Among the solid samples, coal ash contained fairly high concentrations of uranium (33.1 µg g-1) due to enrichment from coal burning. In addition, uranium levels in the other solid samples were around 2.8 µg g-1 (the Earth's average background value). Uranium concentrations in hair and urine samples were 22.2-634.5 ng g-1 (mean: 156.2 ng g-1) and 8.44-761.6 ng L-1 (mean: 202.6 ng L-1), respectively, which are significantly higher than reference values reported for unexposed subjects in other areas. Therefore, these results indicate that people living in this coal mining area have been subjected to uranium exposure for long periods of time.

On the sequential separation and quantification of 237Np, 241Am, thorium, plutonium, and uranium isotopes in environmental and urine samples.

The implementation of the one-pass-through separation technique using two stacked chromatography columns of TEVA - TRU resins for the separation of 237Np, 241Am, thorium, plutonium and uranium from environmental and urine samples was investigated. The sequential separation technique proved to be successful and gave similar results to those obtained when using individual separations. The analysis time was considerably improved. The amount of chemical waste was also reduced by 50% and the use of HClO4 was avoided. The technique of ICP-MS was also investigated as a complementary technique to alpha-spectrometry.

Urine uranium concentrations and renal function in residents of the United States--2001 to 2010.

CONTEXT: Animal model studies have demonstrated that subchronic oral uranium exposure is associated with renal dysfunction. Little is known about the effects of environmental exposure to uranium in humans. OBJECTIVE: To determine whether environmental exposure to uranium is associated with alterations in renal function among residents of the United States. METHODS: We analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2001-2010. Inclusion criteria included the measurement of urine uranium concentration, serum creatinine (sCr), and urine albumin-creatinine ratio. Exclusion criteria included a reported history of diabetes mellitus. Urine uranium concentrations were normalized to urinary creatinine. Respondents with and without detectable urine uranium concentrations were compared using Welch's t-test for urine albumin-creatinine ratio and sCr and using Fisher's exact test for a reported history of renal disease. Regression analysis was performed to assess for an association between urine uranium concentration and urine albumin-creatinine ratio, sCr, or a reported history of renal disease. RESULTS: Uranium was detectable in the urine of 74.1% (n = 9025) of respondents. Urine albumin-creatinine ratio was significantly greater in respondents with detectable urine uranium concentrations (mean 4.84 ± 45.8 mg/g) compared to respondents without detectable urine uranium concentrations (mean 0.77 ± 3.7 mg/g) (p < 0.001). There was no significant difference between the groups with respect to sCr or a reported history of renal disease. Regression analysis did not show a statistically significant association between urine uranium concentration and urine albumin-creatinine ratio (p = 0.45), sCr (p = 0.71), or a reported history of renal disease (p = 0.05). CONCLUSIONS: In this study, a high proportion of the U.S. population had exposure to uranium. We demonstrated an association between detectable urine uranium concentrations and microalbuminuria in residents of the United States but no association with clinical renal disease.

Determination of 234U/238U, 235U/238U and 236U/238U isotope ratios in urine using sector field inductively coupled plasma mass spectrometry.

Quantification of the isotopic composition of uranium in urine at low levels of concentration is important for assessing both military and civilian populations' exposures to uranium. However, until now there has been no convenient, precise method established for rapid determination of multiple uranium isotope ratios. Here, the authors report a new method to measure (234)U/(238)U, (235)U/(238)U and (236)U/(238)U. It uses solid-phase chelation extraction (via TRU columns) of actinides from the urine matrix, followed by measurement using a magnetic sector field inductively coupled plasma mass spectrometer (SF-ICP-MS-Thermo Element XR) equipped with a high-efficiency nebulizer (Apex PFA microflow) and coupled with a membrane desolvating nebulizer system (Aridus II™). This method provides rapid and reliable results and has been used successfully to analyse Certified Reference Materials.

Estimation of internal exposure to uranium with uncertainty from urinalysis data using the InDEP computer code.

The National Institute for Occupational Safety and Health (NIOSH) is currently studying mortality in a cohort of 6409 workers at a former uranium processing facility. As part of this study, over 220 000 urine samples were used to reconstruct organ doses due to internal exposure to uranium. Most of the available computational programs designed for analysis of bioassay data handle a single case at a time, and thus require a significant outlay of time and resources for the exposure assessment of a large cohort. NIOSH is currently supporting the development of a computer program, InDEP (Internal Dose Evaluation Program), to facilitate internal radiation exposure assessment as part of epidemiological studies of both uranium- and plutonium-exposed cohorts. A novel feature of InDEP is its batch processing capability which allows for the evaluation of multiple study subjects simultaneously. InDEP analyses bioassay data and derives intakes and organ doses with uncertainty estimates using least-squares regression techniques or using the Bayes' Theorem as applied to internal dosimetry (Bayesian method). This paper describes the application of the current version of InDEP to formulate assumptions about the characteristics of exposure at the study facility that were used in a detailed retrospective intake and organ dose assessment of the cohort.

Characterisation of protracted low-level exposure to uranium in the workplace: A comparison of two approaches.

Retrospective estimates of internal doses received by workers in the nuclear industry following intake of radionuclides, based on bioassay data, are a benchmark method in epidemiological studies. Nonetheless, full information relative to thousands of people included in an epidemiological cohort is rarely available, thus implying difficulties to estimate exposure precisely. To evaluate the cumulative exposure to uranium in a cohort of the AREVA NC Pierrelatte plant workers, we compared the epidemiological Job Exposure Matrix (JEM) method with the dosimetric method based on biological monitoring of exposure for 30 workers randomly selected within the cohort. A moderate to strong correlation was observed between the estimators resulting from the two approaches, thereby validating the JEM as a tool that can be used to characterise cumulative exposure to uranium in the cohort. In addition, this study showed that the JEM is a valuable complement to the interpretation of bioassy, (1) in providing information on exposure periods as well as on physical and chemical form of the radionuclides and (2) in compensating for the lack of exposure data regarding the very earliest periods. Combining the two methods may improve the precision in reconstructing cumulative exposure for epidemiological studies.

Biological monitoring of uranium exposure in south central Virginia.

In May 2004, two groundwater wells in Dinwiddie County, Virginia were found to have natural uranium levels either at or above the EPA recommended limit of 30 microg/l. As a result, a stop drinking water advisory was issued until a water treatment system could be installed to remove the uranium. In response to residents' concerns, and uncertainty of exposures, affected individuals were asked to participate in a voluntary epidemiological investigation of uranium uptake and 1-year uranium retention study. This study had two primary objectives: quantification of the uranium load on the participants, as expressed by their urine uranium concentration, and retention after 1 year of no exposure. A first-morning void urine specimen, along with survey information, was collected from 156 participants in May 2004, with a second collection occurring 12 months later of 91 participants. The samples were analyzed for uranium by ICP/MS, pH, creatinine by the Jaffe method, and RBP by LIA after both collections. A reduction of one order of magnitude for the geometric mean urine uranium concentration was observed, from 0.100 microg/g creatinine to 0.011 microg/g creatinine in 1 year. Comparatively, NHANES has reported that the geometric mean for all participants, ages 6 years and older, is 0.008 microg/g creatinine, with the 95th percentile being 0.040 microg/g creatinine. None of the second round specimens showed a urine uranium concentration higher than baseline for an individual.

Method design and validation for the determination of uranium levels in human urine using high-resolution alpha spectrometry.

Quantification of uranium in human urine is a valuable technique for assessing occupational and public exposure to uranium. A reliable method has been developed and validated in the ARPANSA Radiochemistry Laboratory by means of standard radiochemical separation and purification techniques and measurement using high-resolution alpha spectrometry. This method can be used to evaluate the levels of naturally occurring 234U, 235U and 238U in urine. Method design and validation is the process of defining an analytical requirement, and then confirming that the method under consideration has performance capabilities consistent with what the application requires. The method was designed to measure levels down to 2 mBq/day of total uranium, corresponding to approximately 1/100th of the annual committed effective dose of 20 mSv. Validation tests were developed to assess selectivity, accuracy, recovery and quantification of uncertainty. The radiochemical recovery of this method was measured using (232)U tracer. The typical minimum detectable concentration for total uranium for 24-h urine samples is approximately 0.6 mBq/day or 0.019 microg/day.

Depleted uranium contamination by inhalation exposure and its detection after approximately 20 years: implications for human health assessment.

Inhaled depleted uranium (DU) aerosols are recognised as a distinct human health hazard and DU has been suggested to be responsible in part for illness in both military and civilian populations that may have been exposed. This study aimed to develop and use a testing procedure capable of detecting an individual's historic milligram-quantity aerosol exposure to DU up to 20 years after the event. This method was applied to individuals associated with or living proximal to a DU munitions plant in Colonie New York that were likely to have had a significant DU aerosol inhalation exposure, in order to improve DU-exposure screening reliability and gain insight into the residence time of DU in humans. We show using sensitive mass spectrometric techniques that when exposure to aerosol has been unambiguous and in sufficient quantity, urinary excretion of DU can be detected more than 20 years after primary DU inhalation contamination ceased, even when DU constitutes only approximately 1% of the total excreted uranium. It seems reasonable to conclude that a chronically DU-exposed population exists within the contamination 'footprint' of the munitions plant in Colonie, New York. The method allows even a modest DU exposure to be identified where other less sensitive methods would have failed entirely. This should allow better assessment of historical exposure incidence than currently exists.

Characterization of internal exposure to enriched uranium at a former gaseous diffusion plant.

The National Institute for Occupational Safety and Health (NIOSH) is conducting a nested case-control study of mortality from multiple myeloma involving 581 subjects who worked at the Oak Ridge K-25 Gaseous Diffusion Plant. Internally-deposited uranium is the primary agent being considered in the exposure assessment. Routine operation and maintenance of the plant presented the potential for inhaling uranium of various enrichments. As part of the exposure assessment, records describing the various plant processes and procedures, documentation on the medical monitoring program, uranium urinalysis data, and procedures and analytical methods for monitoring uranium exposure were retrieved and reviewed. Uranium urinalysis data consisted of 161,055 uranium urinalysis results obtained by fluorometry and 171,914 results obtained by alpha particle counting. Approximately 20% of the workers were monitored for internal exposure using urine sampling. Mean and median uranium concentrations in urine for the monitored study subjects were slightly lower than for the entire population of monitored K-25 workers. The specific activity of uranium excreted in urine was determined by comparing results obtained using fluorometric and alpha activity measurements and indicate that the majority of internal exposure involved uranium that was depleted or enriched to no more than 4% U.

Examination of the health status of populations from depleted-uranium-contaminated regions.

During the NATO air strikes on the Federal Republic of Yugoslavia (Serbia and Montenegro) in 1999, depleted-uranium ammunition was used on 112 locations, mainly Kosovo, in the south of Serbia, and one location in Montenegro. Blood samples of residents from depleted-uranium-contaminated areas were gathered and blood cell and chromosomal aberrations were analyzed. During the last 3 years blood samples from 21 residents of Kosovo (Strpce), from 29 residents from the south of Serbia (the Vranje and Bujanovac regions), and from 19 technical television workers from the site of Pljackovica, in the vicinity of Vranje, were collected. Blood samples from 33 residents of central Serbia and 46 occupational workers exposed to X-rays were used as controls. All subjects studied were without any clinical symptoms of disease. The examinations included general clinical assessment; urine samples for alpha-and gamma-spectrometry analysis; complete blood counts; ratio-percentages of blood cells in stained (Giemsa) capillary smears, individual leukocyte line elements; morphological changes observed under a microscope; the presence of immature forms or blasts; and leukocyte enzyme activity [alkaline phosphatase leukocyte (APL)]. Chromosomal aberrations were evaluated in 200 peripheral blood lymphocytes in mitosis. An increased incidence of rogue cells and chromosomal aberrations was found in the blood of the residents of Vranje and Bujanovac, but this was below the incidence of chromosomal aberrations in individuals occupationally exposed to ionizing irradiation. Blast cells were not found. Blood counts were decreased in only a few samples, while morphological changes of both nuclei and cytoplasm were marked in individuals in south and central Serbia. Enzymatic activity (as measured by the APL score) was decreased in samples with chromosomal aberrations and cyto-morphological changes in subjects from the south of Serbia. The contamination level measured by this examination was low. Because of the presence of depleted uranium (uranium-238) in the soil and in plants, the prevention of consequences necessitates the identification of the initial biological effects on sensitive tissues. Early identification of serious blood cell changes is important for appropriate medical treatment.

Validated measurements of the uranium isotopic signature in human urine samples using magnetic sector-field inductively coupled plasma mass spectrometry.

Increased interest in measuring uranium isotope ratios in environmental samples (biological materials, soils, dust particles, water) has come from the necessity to assess the health impact of the use of depleted uranium (DU) based ammunitions during recent military conflicts (e.g., Gulf war, Kosovo) and from the need to identify nondeclared nuclear activities (nuclear safeguards). In this context, very important decisions can arise which have to be based on measurement data of nondisputable uncertainty. The present study describes the certification to 2.5% (k = 2) relative combined uncertainty of n(235U)/n(238U) at ultralow uranium levels (approximately 5-20 pg g(-1)) in human urine samples. After sample decomposition and matrix separation, the isotope ratios were measured by means of a single-detector magnetic sector-field inductively coupled plasma mass spectrometry instrument fitted with an ultrasonic nebulizer. Correction for mass discrimination effects was obtained by means of the certified isotopic reference material IRMM-184. The analytical procedure developed was validated in three complementary ways. First, all major sources of uncertainty were identified and propagated together following the ISO/GUM guidelines. Second, this quality was controlled with a matrix matching NUSIMEP-3 sample (approximately 0.06-0.7% difference from certified). Third, the instrumental part of the procedure was proven to be reproducible from the confirmation of the results obtained for three samples remeasured 7 months later (approximately 1.5% difference). The results obtained for 33 individuals indicated that none seemed to have been exposed to contamination by DU.

[Depleted uranium a cancer risk that disappeared. Leukemia alarm regarding Balkan veterans came to nothing]. / Utarmat uran, en cancerrisk som försvann. Larmrapporterna om leukemi hos balkansoldater kom av sig.

After alarming reports in the international press in January 2001, about leukemia in war veterans returning from the Balkans after possible exposure to depleted uranium, a follow-up was conducted of the Swedish personnel that had served in the Balkans. Questionnaires, analysis of uranium in urine, and coordination with The National Board of Health and Welfare's cancer register showed no correlation between service in the Balkans and cancer or other illnesses. Several did however experience anxiety, insomnia and fatigue that may have been caused by the stressful environment and/or the anxiety arising from the depleted uranium-debate. To lower the risk for unjustified anxiety and to be better prepared for the physical environment, the Swedish Armed Forces are working on better risk analysis before mission as well as increased health examinations both before and after mission.

Uranium and thorium in urine of United States residents: reference range concentrations.

We measured uranium and thorium in urine of 500 U. S. residents to establish reference range concentrations using a magnetic-sector inductively coupled argon plasma mass spectrometer (ICP-MS). We found uranium at detectable concentrations in 96.6% of the urine specimens and thorium in 39.6% of the specimens. The 95th percentile concenetration for uranium was 34.5 ng/L (parts per trillion); concentrations ranged up to 4080 ng/L. Thorium had a 95th percentile concentration of 3.09 ng/L; concentrations ranged up to 7.7 ng/L.