Chemical and radiological effects of chronic ingestion of uranium in the rat brain: biochemical impairment of dopaminergic, serotonergic and cholinergic neuro-transmissions; Effets chimique et radiologique d'une ingestion chronique d'uranium sur le cerveau du rat. Effets sur les neurotransmissions dopaminergique, serotoninergique et cholinergique

Energy Technology Data Exchange (ETDEWEB)

Bussy, C

2005-09-15

Uranium is an environmental ubiquitous metal-trace element. It has both chemical and radiological toxicity. After chronic ingestion, uranium can distribute in any part of the body and accumulate in the brain. The aims of this study was 1) to determine and estimate the effects of uranium on dopaminergic, serotoninergic and cholinergic systems and 2) to measure the uranium amount in the brain, after chronic exposure by ingestion of depleted (D.U.) or enriched (E.U.) uranium during 1.5 to 18 months at 40 mg.L{sup -1} (40 ppm) in different rat brain areas. At any time of exposure, the results show that both the neurotransmission alterations and the uranium brain accumulation were moderate, area specific, time-evolutive and depended on uranium specific activity. After D.U. exposure, monoamine perturbations are chronic and progressive. On the contrary, monoamine alterations occurred only after long term of E.U. exposure. These mono-aminergic modifications are not always dependent on uranium accumulation in brain areas. Moreover, although the cholinergic system was not affected at both 1.5 and 9 months of D.U. exposure, the alteration of ChE activity after E.U. exposure are both dependent on uranium accumulation in brain areas and on uranium specific activity. After E.U. exposure, cholinergic modification and uranium accumulation in hippocampus could partially explain the short-term memory disturbances which have been previously reported. (author)

Metabolomics identifies a biological response to chronic low-dose natural uranium contamination in urine samples.

Science.gov (United States)

Grison, Stéphane; Favé, Gaëlle; Maillot, Matthieu; Manens, Line; Delissen, Olivia; Blanchardon, Eric; Banzet, Nathalie; Defoort, Catherine; Bott, Romain; Dublineau, Isabelle; Aigueperse, Jocelyne; Gourmelon, Patrick; Martin, Jean-Charles; Souidi, Maâmar

2013-01-01

Because uranium is a natural element present in the earth's crust, the population may be chronically exposed to low doses of it through drinking water. Additionally, the military and civil uses of uranium can also lead to environmental dispersion that can result in high or low doses of acute or chronic exposure. Recent experimental data suggest this might lead to relatively innocuous biological reactions. The aim of this study was to assess the biological changes in rats caused by ingestion of natural uranium in drinking water with a mean daily intake of 2.7 mg/kg for 9 months and to identify potential biomarkers related to such a contamination. Subsequently, we observed no pathology and standard clinical tests were unable to distinguish between treated and untreated animals. Conversely, LC-MS metabolomics identified urine as an appropriate biofluid for discriminating the experimental groups. Of the 1,376 features detected in urine, the most discriminant were metabolites involved in tryptophan, nicotinate, and nicotinamide metabolic pathways. In particular, N -methylnicotinamide, which was found at a level seven times higher in untreated than in contaminated rats, had the greatest discriminating power. These novel results establish a proof of principle for using metabolomics to address chronic low-dose uranium contamination. They open interesting perspectives for understanding the underlying biological mechanisms and designing a diagnostic test of exposure.

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)

Occupational exposures to uranium: processes, hazards, and regulations

International Nuclear Information System (INIS)

Stoetzel, G.A.; Fisher, D.R.; McCormack, W.D.; Hoenes, G.R.; Marks, S.; Moore, R.H.; Quilici, D.G.; Breitenstein, B.D.

1981-04-01

The United States Uranium Registry (USUR) was formed in 1978 to investigate potential hazards from occupational exposure to uranium and to assess the need for special health-related studies of uranium workers. This report provides a summary of Registry work done to date. The history of the uranium industry is outlined first, and the current commercial uranium industry (mining, milling, conversion, enrichment, and fuel fabrication) is described. This description includes information on basic processes and areas of greatest potential radiological exposure. In addition, inactive commercial facilities and other uranium operations are discussed. Regulation of the commercial production industry for uranium fuel is reported, including the historic development of regulations and the current regulatory agencies and procedures for each phase of the industry. A review of radiological health practices in the industry - facility monitoring, exposure control, exposure evaluation, and record-keeping - is presented. A discussion of the nonradiological hazards of the industry is provided, and the final section describes the tissue program developed as part of the Registry

Constitution of a group of Czech and French uranium miners in order to estimate lung cancer risk linked to low chronic exposure to radon decay products

International Nuclear Information System (INIS)

Tirmarche, M.; Tomasek, L.

1996-01-01

West Bohemian and French uranium miners are characterized by a long duration of exposure to radon and its decay products, in comparison to most of the other groups of miners, studied in the recent international joint analysis by the National Cancer Institute (NCI) in USA. This analysis has confirmed the linearly increasing risk of lung cancer by cumulative radon exposure, describing the different factors that may influence this dose-response relationship. One of the main factors presently discussed is the influence of the exposure-rate effect: in other words, has the same cumulated exposure spread over 10 years the same risk of lung cancer as if it is cumulated in 2 years? The implication of an inverse exposure-rate effect for low chronic exposures as well as some methodological approaches will be discussed and tested by using the data of the Czech and French cohorts. These two cohorts present annual exposures varying by a factor of 5 to 10, French exposure rates being close or even less than 0.1 Working Level during the last 20 years. The project is integrated in a larger European project on uranium miners, co-ordinated by IPSN. (author)

Compared biokinetic and biological studies of chronic and acute inhalations of uranium compounds in the rat

International Nuclear Information System (INIS)

Monleau, M.

2005-12-01

Uranium is a natural, radioactive heavy metal, widely used in the nuclear industry in various chemical and isotopic forms. Its use in the fuel cycle involves the risk of radiological exposure for the workers, mainly via the inhalation of uranium particles. According to the workplace configuration, uranium contaminations can be acute or repeated, involve various chemical forms and different levels of enrichment, as well as involving one or several components. The dosimetric concepts and models available for workers' radiological protection, as well as most of the studies of the biological effects, correspond to acute exposure situations. Moreover the processes leading to pathological effects are little known in vivo. In this context, the main question is to know whether exposures due to repeated inhalation by rats induce the element kinetics and toxicity, which may be different from those observed after an acute exposure. In this study, comparison of the experimental and theoretical biokinetics of an insoluble uranium repeatedly inhaled over three weeks shows that a chronic contamination is correctly modelled, except for bone retention, by the sum of acute, successive and independent incorporations. Moreover, the kinetics of a soluble uranium inhaled irregularly can be modified by previous repeated exposure to an insoluble uranium. In certain cases therefore, exposure to uranium could modify its biokinetics during later exposures. At a toxicological level, the study demonstrates that the uranium particles inhaled repeatedly induce behavioural disruptions and genotoxic effects resulting in various sorts of DNA damage, in several cell types and certainly depending on the quantity inhaled. Exposures involving several uraniferous components produce a synergy effect. Moreover, repeated inhalations worsen the genotoxic effects in comparison to an acute exposure. This work demonstrates the importance of not ignoring the effects of the repetition of uranium exposure. It

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.

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

Does uranium exposure induce oxidative stress and genotoxicity in the teleostean Danio rerio? first experimental results

International Nuclear Information System (INIS)

Barillet, S.; Devaux, A.; Simon, O.; Buet, A.; Pradines, C.

2004-01-01

Within the Envirhom research program, key advances have been obtained in uranium bioaccumulation and underlying mechanisms understanding in various biological models at the individual level. However, considering different scales of biological effects (from early to delayed ones, from low to high level of organization) is crucial to provide ecologically relevant indicators. Organisms counteract stress induced by pollutant exposure through a wide range of physiological responses being both dose and time dependent. Effects at higher hierarchical levels are always preceded by early changes in biological processes, from subtle biochemical disturbances to impaired physiological functions, increased susceptibility to other stresses, reduced life-span Within this global context, preliminary experiments were carried out on adult zebra fish (Danio rerio), to assess early changes after short-term uranium exposure. Among the subsequent primary subcellular damages oxidative stress and genotoxicity (characterizing both chemo-toxicity and radiotoxicity) are relevant endpoints, thus requiring the knowledge of dose-effects relationships as a first operational approach to provide useful tool in predicting possible effects of U exposure. Zebra fish has been selected due to its small size (facilitating its maintenance) and its extended use in eco-toxicological studies. Moreover, its short life-cycle will allow to carry out chronic exposure experiments (along the whole life-cycle). Four uranium concentrations (0, 20, 100 and 500μg.L -1 ) and five sampling times (0, 0.5, 1, 5 and 10 days) were selected. Catalase, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were measured as oxidative stress bio-markers. DNA damage level was assessed in zebra fish erythrocytes using the comet assay. Uranium bioaccumulation was concurrently studied to understand observed bio-marker responses. Further experiments, dedicated to the assessment of the impact of chronic uranium

Uranium internal exposure evaluation based on urine assay data

International Nuclear Information System (INIS)

Lawrence, J.N.P.

1984-09-01

The difficulties in assessing internal exposures to uranium from urine assay data are described. A simplified application of the ICRP-30 and ICRP Lung Model concepts to the estimation of uranium intake is presented. A discussion follows on the development of a computer code utilizing the ICRP-30-based uranium elimination model with the existing urine assay information. The calculated uranium exposures from 1949 through 1983 are discussed. 13 references, 1 table

Irradiation Stability of Uranium Alloys at High Exposures

International Nuclear Information System (INIS)

McDonell, W.R.

2001-01-01

Postirradiation examinations were begun of a series of unrestrained dilute uranium alloy specimens irradiated to exposures up to 13,000 MWD/T in NaK-containing stainless steel capsules. This test, part of a program of development of uranium metal fuels for desalination and power reactors sponsored by the Division of Reactor Development and Technology, has the objective of defining the temperature and exposure limits of swelling resistance of the alloyed uranium. This paper discusses those test results

Calculation of gamma ray exposure rates from uranium ore bodies

International Nuclear Information System (INIS)

Thomson, J.E.; Wilson, O.J.

1980-02-01

The planning of operations associated with uranium mines often requires that estimates be made of the exposure rates from various ore bodies. A straight-forward method of calculating the exposure rate from an arbitrarily shaped body is presented. Parameters for the calculation are evaluated under the assumption of secular equilibrium of uranium with its daughters and that the uranium is uniformly distributed throughout an average soil mixture. The spectral distribution of the emitted gamma rays and the effect of air attenuation are discussed. Worked examples are given of typical situations encountered in uranium mines

The Toxicity of Depleted Uranium

OpenAIRE

Briner, Wayne

2010-01-01

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 c...

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)

Study of the biological effects of uranium exposure on zebra fish (D. rerio). Impact on life stages

International Nuclear Information System (INIS)

Bourrachot, St.

2009-05-01

This work is part of an ongoing project (ENVIRHOM) started at IRSN in 2000, which consists in studying the environmental effects of radioactive substances at chronic low level of exposure. In this general frame, our aim was two fold: (i) to identify sensitivity of different critical life stages of zebra fish (fish of fresh water frequently used for tests standards in ecotoxicology) to uranium exposure and (ii) to evaluate underlying mechanisms. Experiments were conducted with eggs, larvae and genitors exposed to uranium at environmentally relevant concentrations (from 20 to 500 μg/L) in order to study survival, hatching of eggs, growth of larvae and reproduction of genitors. Bio-markers of exposure (i.e. U bioaccumulation) and bio-markers of effects at molecular level (i.e. genotoxic effects, reproductive-toxicity) were also measured. Sensitivity of fish to uranium was dependent of the life stage of development with the early life stage being the most sensitive to U either directly or maternally exposed. It underlines the relevance of including pro-larval stages for toxicity assessments in fish. Moreover drastic effects of uranium on reproductive success and DNA damages in the germ cells foretell a strong impact on the population for low concentration of exposure (20 μg/L). As it is increasingly recognized that population-level effects of toxic substances are more relevant in terms of ecological risk assessment, this study points out the need to include different life stages of organisms in eco-toxicological studies, especially the sensitive early stages. Moreover, it appears, through the comparative study of the radiological effects or by another isotope of the uranium of stronger radioactivity ( 233 U or by an irradiation with 137 Cs), that the effects of the uranium are due to its chemo-toxicity. (author)

Epi-genetics modifications induced by a depleted uranium exposure in the zebra fish

Energy Technology Data Exchange (ETDEWEB)

Gombeau, K.; Pereira, S.; Adam-Guillermin, C. [IRSN/PRP-ENV/SERIS/LECO (France); Bourdineaud, J.P. [UMR CNRS 5805 EPOC (France); Ravanat, J.L. [INAC/Scib UMR E3 CEA-UJF (France)

2014-07-01

The work presented here integrates in the general framework of assessment of effects of chronic exposure to low doses of radionuclides. This evaluation necessarily involves the study of the mechanisms of toxic action at the cellular or subcellular level, in order to better understand the processes of propagation of effects to the level of the populations or ecosystems. As such, the question of the mechanisms underlying the trans-generational effects and the adaptive capacity of organisms is central, both in humans and in animal species. Epigenetic refer to changes in gene function that do not involve changes in DNA sequence, and which are transmitted in a hereditary manner by mitosis or meiosis. The latter plays a key role in these trans-generational effects. Among these changes, DNA-methylation is one of the most studied epigenetic parameters. This work is part of a PhD, included in the European COMET project (Euratom 7. Framework Program), and focuses on epigenetic modifications induced in zebra fish after a chronic exposure to radionuclides. Male and female fishes were exposed to 2 and 20 μg.L{sup -1} of depleted uranium for 24 days. After 7 and 24 days of exposure, brain, gonads, and eyes were collected in order to study changes in DNA methylation. In addition, genotoxicity was measured by the γH2AX assay. The overall changes in DNA methylation were studied by AFLP-MS and HPLC-MS, in order to know if the exposure to depleted uranium changes the global status of DNA methylation. We have found a decrease in the global level of methylation in the eyes of males after 24 days of exposure, the diminution being much more important and significant at the higher concentration of exposure (11.79 ± 3.62 against 52.43 ± 3.01 for controls) This study will be refined by analyzing the methylation of specific regions of the genome, because it represent the sequences of genes involved in major physiological functions and that may be subject to variations in the methylation

Radiation exposure of uranium mill workers

International Nuclear Information System (INIS)

Jha, Giridhar; Saha, S.C.

1982-01-01

The uranium mill workers at Jaduguda were covered by a regular film badge service from 1969 onwards. Since the log normal plot is useful in interpreting occupational exposure, a statistical analysis of the radiation exposure data was attempted. Exposure data for each year has been plotted as cumulative percentage and worker's population with exposure levels in different class intervals. The plot for each of the year under investigation shows an occupational exposure distribution more or less consistent with the log normal distribution function. The analysis shows that more than 98% of radiation workers received less than 200 mrem (2 mSv). (author)

Chronic uranium exposure and growth toxicity for phytoplankton. Dose-effect relationship: first comparison of chemical and radiological toxicity

International Nuclear Information System (INIS)

Gilbin, R.; Pradines, C.; Garnier-Laplace, J.

2004-01-01

The bioavailability of uranium for freshwater organisms, as for other dissolved metals, is closely linked to chemical speciation in solution (U aqueous speciation undergoes tremendous changes in the presence of ligands commonly found in natural waters e.g. carbonate, phosphate, hydroxide and natural organic matter). For the studied chemical domain, short-term uranium uptake experiments have already shown that the free uranyl ion concentration [UO 2 2+ ] is a good predictor of uranium uptake by the green algae Chlamydomonas reinhardtii, as predicted by the Free Ion Activity Model. In agreement with these results, acidic pH and low ligands concentrations in water enhance uranium bioavailability and consequently its potential chronic effects on phytoplankton. Moreover, uranium is known to be both radio-toxic and chemo-toxic. The use of different isotopes of uranium allows to expose organisms to different radiological doses for the same molar concentration: e.g. for a given element concentration (chemical dose), replacing depleted U by U-233 obviously leads to an enhanced radiological delivered dose to organisms (x10 4 ). In this work we established relationships between uranium doses (depleted uranium and 233-U ) and effect on the growth rate of the green algae Chlamydomonas reinhardtii. Uranium bioaccumulation was also monitored. Growth rate was measured both in classical batch (0-72 hrs) and continuous (turbidostat) cultures, the latter protocol allowing medium renewal to diminish exudates accumulation and speciation changes in the medium. The differences in effects will be, if possible, related to the development of defence mechanisms against the formation of reactive oxygen species (forms of glutathione) and the production of phyto-chelatins (small peptides rich in cystein that play an important role in the homeostasis and the detoxication of metals in cells). (author)

Influence of chronic exposure to uranium on male reproduction in mice

International Nuclear Information System (INIS)

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

1991-01-01

Relatively few data are available concerning the reproductive and developmental toxicity of uranium. The present study was designed to evaluate the reproductive effects of this metal in male Swiss mice. The animals were treated with uranyl acetate dihydrate at doses of 0, 10, 20, 40, and 80 mg/kg/day given in the drinking water for 64 days. To evaluate the fertility of the uranium-treated males, mice were mated with untreated females for 4 days. There was a significant but non-dose-related decrease in the pregnancy rate of these animals. Body weights were significantly depressed only in the 80 mg/kg/day group. Testicular function/spermatogenesis was not affected by uranium at any dose, as evidenced by normal testes and epididymis weights and normal spermatogenesis, whereas interstitial alterations and vacuolization of Leydig cells were seen at 80 mg/kg/day. The results of this investigation indicate that uranium does not cause any adverse effect on testicular function in mice at the concentrations usually ingested in the diet and drinking water, with a safety factor of more than 1000. However, although spermatogenesis was not affected by uranium administration, uranium produces a significant decrease in the pregnancy rate at 10, 20, 40, or 80 mg/kg/day

Secondary limits of exposure in facilities handling uranium

International Nuclear Information System (INIS)

Raghavayya, M.

1999-08-01

Annual limits of exposure and intake for radiation workers in nuclear installations have been recommended by the International Commission on Radiological Protection and the same have been adopted by the Indian Atomic Energy Regulatory Board for all the radionuclides of interest. The prescribed limits cannot be directly used for day to day radiation protection work. Hence secondary limits have to be derived for routine applications. The modeling steps may be simple in some situations and more complicated in some others. The limits recommended are for individual radionuclides. But in facilities handling natural or enriched uranium the radionuclides (isotopes of uranium and its decay products) generally occur together in specific ratios. Derivation of secondary limits has to take this into consideration. The present document is an attempt at deriving the secondary limits required for routine application in facilities handling uranium (Mine, mill, refineries and fuel fabrication etc.). Secondary limits of exposure have been derived in this document for air borne activity, activity in water, surface contamination and internal exposures. (author)

Y-12 Uranium Exposure Study

Energy Technology Data Exchange (ETDEWEB)

Eckerman, K.F.; Kerr, G.D.

1999-08-05

Following the recent restart of operations at the Y-12 Plant, the Radiological Control Organization (RCO) observed that the enriched uranium exposures appeared to involve insoluble rather than soluble uranium that presumably characterized most earlier Y-12 operations. These observations necessitated changes in the bioassay program, particularly the need for routine fecal sampling. In addition, it was not reasonable to interpret the bioassay data using metabolic parameter values established during earlier Y-12 operations. Thus, the recent urinary and fecal bioassay data were interpreted using the default guidance in Publication 54 of the International Commission on Radiological Protection (ICRP); that is, inhalation of Class Y uranium with an activity median aerodynamic diameter (AMAD) of 1 {micro}m. Faced with apparently new workplace conditions, these actions were appropriate and ensured a cautionary approach to worker protection. As additional bioassay data were accumulated, it became apparent that the data were not consistent with Publication 54. Therefore, this study was undertaken to examine the situation.

The brain is a target organ after acute exposure to depleted uranium.

Science.gov (United States)

Lestaevel, P; Houpert, P; Bussy, C; Dhieux, B; Gourmelon, P; Paquet, F

2005-09-01

The health effects of depleted uranium (DU) are mainly caused by its chemical toxicity. Although the kidneys are the main target organs for uranium toxicity, uranium can also reach the brain. In this paper, the central effects of acute exposure to DU were studied in relation to health parameters and the sleep-wake cycle of adult rats. Animals were injected intraperitoneally with 144+/-10 microg DU kg-1 as nitrate. Three days after injection, the amounts of uranium in the kidneys represented 2.6 microg of DU g-1 of tissue, considered as a sub-nephrotoxic dosage. The central effect of uranium could be seen through a decrease in food intake as early as the first day after exposure and shorter paradoxical sleep 3 days after acute DU exposure (-18% of controls). With a lower dosage of DU (70+/-8 microg DU kg-1), no significant effect was observed on the sleep-wake cycle. The present study intends to illustrate the fact that the brain is a target organ, as are the kidneys, after acute exposure to a moderate dosage of DU. The mechanisms by which uranium causes these early neurophysiological perturbations shall be discussed.

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

The brain is a target organ after acute exposure to depleted uranium

International Nuclear Information System (INIS)

Lestaevel, P.; Houpert, P.; Bussy, C.; Dhieux, B.; Gourmelon, P.; Paquet, F.

2005-01-01

The health effects of depleted uranium (DU) are mainly caused by its chemical toxicity. Although the kidneys are the main target organs for uranium toxicity, uranium can also reach the brain. In this paper, the central effects of acute exposure to DU were studied in relation to health parameters and the sleep-wake cycle of adult rats. Animals were injected intraperitoneally with 144 ± 10 μg DU kg -1 as nitrate. Three days after injection, the amounts of uranium in the kidneys represented 2.6 μg of DU g -1 of tissue, considered as a sub-nephrotoxic dosage. The central effect of uranium could be seen through a decrease in food intake as early as the first day after exposure and shorter paradoxical sleep 3 days after acute DU exposure (-18% of controls). With a lower dosage of DU (70 ± 8 μg DU kg -1 ), no significant effect was observed on the sleep-wake cycle. The present study intends to illustrate the fact that the brain is a target organ, as are the kidneys, after acute exposure to a moderate dosage of DU. The mechanisms by which uranium causes these early neurophysiological perturbations shall be discussed

Exposure to recycled uranium contaminants in gaseous diffusion plants

International Nuclear Information System (INIS)

Anderson, Jeri L.; Yiin, James H.; Tseng, Chih-Yu; Apostoaei, A. Iulian

2017-01-01

As part of an ongoing study of health effects in a pooled cohort of gaseous diffusion plant workers, organ dose from internal exposure to uranium was evaluated. Due to the introduction of recycled uranium into the plants, there was also potential for exposure to radiologically significant levels of "9"9Tc, "2"3"7Np and "2"3"8","2"3"9Pu. In the evaluation of dose response, these radionuclide exposures could confound the effect of internal uranium. Using urine bioassay data for study subjects reported in facility records, intakes and absorbed dose to bone surface, red bone marrow and kidneys were estimated as these organs were associated with a priori outcomes of interest. Additionally, "9"9Tc intakes and doses were calculated using a new systemic model for technetium and compared to intakes and doses calculated using the current model recommended by the International Commission on Radiological Protection. Organ absorbed doses for the transuranics were significant compared to uranium doses; however, "9"9Tc doses calculated using the new systemic model were significant as well. Use of the new model resulted in an increase in "9"9Tc-related absorbed organ dose of a factor of 8 (red bone marrow) to 30 (bone surface). (authors)

Reproductive toxicity in rats after chronic oral exposure to low dose of depleted uranium

International Nuclear Information System (INIS)

Li Rong; Ai Guoping; Xu Hui; Su Yongping; Cheng Tianmin; Leng Yanbing

2007-01-01

Objective: To study the reproductive toxicity in rats induced by low dose of depleted uranium (DU). Methods: Male and female rats(F 0 generation) were exposed to DU in food at doses of 0, 0.4, 4 and 40 mg·kg -1 ·d -1 for 160 days, respectively. Then the activities of enzymes in testis and sexual hormone contents in serum were detected. Mature male rats were mated with female rats exposed to the same doses for 14 days. Pregnant rate and normal labor rate in F 0 rats were detected, as well as the survival rate and weight of F 1 rats within 21 d after birth. Results: No adverse effects of DU on fertility were evident at any dose in F 0 rats. Compared with control group, the rate of pregnancy, normal labor, survival of offspring birth and offspring nurture in F 1 generation of high-dose group reduced to 40.0%, 33.3%, 33.3%, and 33.3%, respectively. The sexual hormone contents in F 0 generation exposed increased, but those in Fl rats decreased significantly. The activities of lactate dehydrogenase-X (LDH-X) decreased in F 1 rats exposed to high-dose of DU, and those of sorbitol dehydrogenase (SDH), LDH and Na + -K + -ATPase decreased in F 1 rats exposed to DU. Conclusions: Reproduction function, growth and development of F 0 rats are not obviously affected after chronic oral exposure to DU, while the toxicity effects in F 1 generation was observed at any dose. (authors)

Ailing uranium millworkers seek recognition, aid

International Nuclear Information System (INIS)

Ambler, M.

1980-01-01

Uranium millworkers who helped produce uranium for the U.S. nuclear defense program in the 1950's and 1960's are suing the federal government and uranium companies for compensation for illnesses that they believe are job-related. Symptoms of these illnesses include frequent blackouts, chronic bronchitis, asthma, constant fatigue, and susceptibility to colds. Research is being conducted to determine whether the millworkers' symptoms are due to excessive radiation exposure. Studies to date indicated that during the 1950's and early 1960's, radiation protection procedures at uranium milling facilities were extremely deficient

Uranium mining sites - Thematic sheets

International Nuclear Information System (INIS)

2009-01-01

A first sheet proposes comments, data and key numbers about uranium extraction in France: general overview of uranium mining sites, status of waste rock and tailings after exploitation, site rehabilitation. The second sheet addresses the sources of exposure to ionizing radiations due to ancient uranium mining sites: discussion on the identification of these sources associated with these sites, properly due to mining activities or to tailings, or due to the transfer of radioactive substances towards water and to the contamination of sediments, description of the practice and assessment of radiological control of mining sites. A third sheet addresses the radiological exposure of public to waste rocks, and the dose assessment according to exposure scenarios: main exposure ways to be considered, studied exposure scenarios (passage on backfilled path and grounds, stay in buildings built on waste rocks, keeping mineralogical samples at home). The fourth sheet addresses research programmes of the IRSN on uranium and radon: epidemiological studies (performed on mine workers; on French and on European cohorts, French and European studies on the risk of lung cancer associated with radon in housing), study of the biological effects of chronic exposures. The last sheet addresses studies and expertises performed by the IRSN on ancient uranium mining sites in France: studies commissioned by public authorities, radioactivity control studies performed by the IRSN about mining sites, participation of the IRSN to actions to promote openness to civil society

In vivo effects of a chronic contamination by uranium or cesium 137 on the pharmaceutical metabolism, of the vitamin D and cholesterol

International Nuclear Information System (INIS)

Souidi, M.

2006-11-01

In conclusion, an animal model, miming the chronic contamination of the populations exposed to the uranium, was used for the first time to show that the chronic ingestion of a weak dose of depleted uranium can affect the level of active vitamin D without modifying the mineral homeostasis. This study shows that this radionuclide can lead molecular modifications of the CYPs and the nuclear receivers involved in the metabolism of the vitamin D not only at the level of the liver and kidney but also at the level of the independent metabolism in the brain. The deficiency in vitamin D can provoke osseous diseases such as the rickets at the child and the osteomalacia at the adult. The three categories of population the most exposed to this deficiency are the infants, the pregnant women and the old persons. Strong prevalence of the vitamin D deficiency associated with a chronic exposure to uranium could lead to osseous disorders. To verify this hypothesis, it will be necessary secondly to realize this study on individuals animal models predisposed to the rickets or to the osteomalacia. (N.C.)

Overview of toxicity data and risk assessment methods for evaluating the chemical effects of depleted uranium compounds

International Nuclear Information System (INIS)

Hartmann, H.M.; Monette, F.A.; Avci, H.I.

2000-01-01

In the United States, depleted uranium is handled or used in several chemical forms by both governmental agencies and private industry (primarily companies producing and machining depleted uranium metal for military applications). Human exposure can occur as a result of handling these compounds, routine low-level effluent releases to the environment from processing facilities, or materials being accidentally released from storage locations or during processing or transportation. Exposure to uranium can result in both chemical and radiological toxicity, but in most instances chemical toxicity is of greater concern. This article discusses the chemical toxic effects from human exposure to depleted uranium compounds that are likely to be handled during the long-term management and use of depleted uranium hexafluoride (UF 6 ) inventories in the United States. It also reviews representative publications in the toxicological literature to establish appropriate reference values for risk assessments. Methods are described for evaluating chemical toxicity caused by chronic low-level exposure and acute exposure. Example risk evaluations are provided for illustration. Preliminary results indicate that chemical effects of chronic exposure to uranium compounds under normal operating conditions would be negligibly small. Results also show that acute exposures under certain accident conditions could cause adverse chemical effects among the populations exposed.

Radon exposure in uranium mining industry vs. exposure in tourist caves

International Nuclear Information System (INIS)

Quindos Poncela, L.; Fernandez Navarro, P.; Sainz Fernandez, C.; Gomez Arozamena, J.; Bordonoba Perez, M.

2004-01-01

There is a fairly general consensus among health physicists and radiation professionals that exposure to radon progeny is the largest and most variable contribution to the population's exposure to natural sources of radiation. However, this exposure is the subject of continuing debate concerning the validity of risk assessment and recommendations on how to act in radon-prone areas. The purpose of this contribution is to situate the radon issue in Spain in two very different settings. The first is a uranium mining industry located in Saelices el Chico (Salamanca), which is under strict control of the Spanish Nuclear Safety Council (CSN). We have measured radon concentrations in different workplaces in this mine over a five-year period. The second setting comprises four tourist caves, three of which are located in the province of Cantabria and the fourth on the Canary Island of Lanzarote. These caves are not subject to any administrative control of radiation exposure. Measured air 222 Rn concentrations were used to estimate annual effective doses due to radon inhalation in the two settings, and dose values were found to be from 2 to 10 times lower in the uranium mine than in the tourist caves. These results were analysed in the context of the new European Basic Safety Standards Directive (EU-BSS, 1996). (authors)

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

Depleted uranium: Metabolic disruptor?; Uranium appauvri: perturbateur metabolique?

Energy Technology Data Exchange (ETDEWEB)

Souidi, Maamar; Dublineau, Isabelle; Lestaevel, Philippe [Institut de Radioprotection et de Surete Nucleaire - IRSN, Direction de la radioprotection de l' homme, Laboratoire de radiotoxicologie experimentale, Service de radiobiologie et d' epidemiologie, BP 17, 92262 Fontenay-aux-Roses cedex (France)

2011-11-15

The presence of uranium in the environment can lead to long-term contamination of the food chain and of water intended for human consumption and thus raises many questions about the scientific and societal consequences of this exposure on population health. Although the biological effects of chronic low-level exposure are poorly understood, results of various recent studies show that contamination by depleted uranium (DU) induces subtle but significant biological effects at the molecular level in organs including the brain, liver, kidneys and testicles. For the first time, it has been demonstrated that DU induces effects on several metabolic pathways, including those metabolizing vitamin D, cholesterol, steroid hormones, acetylcholine and xenobiotics. This evidence strongly suggests that DU might well interfere with many metabolic pathways. It might thus contribute, together with other man-made substances in the environment, to increased health risks in some regions. (authors)

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)

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)

External exposure from gamma radiation in uranium mines

International Nuclear Information System (INIS)

Thomson, J.E.

1982-01-01

Radiation doses received by workers in a high ore grade uranium mine are compared to those of other radiation workers and the need to be able to calculate the exposure rate from an ore body is indicated. The uranium-238 decay chain is presented and particular reference is made to the main gamma emitters and secular equilibrium of the members of the chain. Difficulties in dealing with a self attenuating volume source, in which scattering is important, are pointed out and traditional methods of solution are mentioned. It is shown that in the special case of an infinite ore body a simple solution may be obtained using the energy conservation principle. A straightforward method for calculating the exposure rate from an arbitrarily shaped ore body is given and corrections due to air attenuation, different soil types and possible lack of secular equilibrium are dealt with. The gamma ray spectrum from the ore is discussed with specific reference to the selection of suitable exposure monitors and the calculation of transmission through shields

Compared biokinetic and biological studies of chronic and acute inhalations of uranium compounds in the rat; Etudes biocinetique et biologique comparees d'inhalations chroniques et aigues de composes uraniferes chez le rat

Energy Technology Data Exchange (ETDEWEB)

Monleau, M

2005-12-15

Uranium is a natural, radioactive heavy metal, widely used in the nuclear industry in various chemical and isotopic forms. Its use in the fuel cycle involves the risk of radiological exposure for the workers, mainly via the inhalation of uranium particles. According to the workplace configuration, uranium contaminations can be acute or repeated, involve various chemical forms and different levels of enrichment, as well as involving one or several components. The dosimetric concepts and models available for workers' radiological protection, as well as most of the studies of the biological effects, correspond to acute exposure situations. Moreover the processes leading to pathological effects are little known in vivo. In this context, the main question is to know whether exposures due to repeated inhalation by rats induce the element kinetics and toxicity, which may be different from those observed after an acute exposure. In this study, comparison of the experimental and theoretical biokinetics of an insoluble uranium repeatedly inhaled over three weeks shows that a chronic contamination is correctly modelled, except for bone retention, by the sum of acute, successive and independent incorporations. Moreover, the kinetics of a soluble uranium inhaled irregularly can be modified by previous repeated exposure to an insoluble uranium. In certain cases therefore, exposure to uranium could modify its biokinetics during later exposures. At a toxicological level, the study demonstrates that the uranium particles inhaled repeatedly induce behavioural disruptions and genotoxic effects resulting in various sorts of DNA damage, in several cell types and certainly depending on the quantity inhaled. Exposures involving several uraniferous components produce a synergy effect. Moreover, repeated inhalations worsen the genotoxic effects in comparison to an acute exposure. This work demonstrates the importance of not ignoring the effects of the repetition of uranium exposure. It

Emergency exposure levels for natural uranium

International Nuclear Information System (INIS)

Spoor, N.L.; Harrison, N.T.

1980-12-01

An attempt is made to identify the inhalation hazards associated with the over-exposure of workers and of the general public, following an accidental release of uranium hexafluoride. Maximum emergency concentrations are recommended for periods of 10, 30, and 60 minutes. The quantitative aspect of the assessment is considered in the context of the development of exposure standards for chemical substances and this facilitates the derivation of levels which are compatible with occupational and public health experience and attainable by management, and to which most workers and members of the general public may be exposed without adverse effect. The radiological implications are also considered. (author)

Compared biokinetic and biological studies of chronic and acute inhalations of uranium compounds in the rat; Etudes biocinetique et biologique comparees d'inhalations chroniques et aigues de composes uraniferes chez le rat

Energy Technology Data Exchange (ETDEWEB)

Monleau, M

2005-12-15

Uranium is a natural, radioactive heavy metal, widely used in the nuclear industry in various chemical and isotopic forms. Its use in the fuel cycle involves the risk of radiological exposure for the workers, mainly via the inhalation of uranium particles. According to the workplace configuration, uranium contaminations can be acute or repeated, involve various chemical forms and different levels of enrichment, as well as involving one or several components. The dosimetric concepts and models available for workers' radiological protection, as well as most of the studies of the biological effects, correspond to acute exposure situations. Moreover the processes leading to pathological effects are little known in vivo. In this context, the main question is to know whether exposures due to repeated inhalation by rats induce the element kinetics and toxicity, which may be different from those observed after an acute exposure. In this study, comparison of the experimental and theoretical biokinetics of an insoluble uranium repeatedly inhaled over three weeks shows that a chronic contamination is correctly modelled, except for bone retention, by the sum of acute, successive and independent incorporations. Moreover, the kinetics of a soluble uranium inhaled irregularly can be modified by previous repeated exposure to an insoluble uranium. In certain cases therefore, exposure to uranium could modify its biokinetics during later exposures. At a toxicological level, the study demonstrates that the uranium particles inhaled repeatedly induce behavioural disruptions and genotoxic effects resulting in various sorts of DNA damage, in several cell types and certainly depending on the quantity inhaled. Exposures involving several uraniferous components produce a synergy effect. Moreover, repeated inhalations worsen the genotoxic effects in comparison to an acute exposure. This work demonstrates the importance of not ignoring the effects of the repetition of uranium exposure

Joint analysis of French and Czech uranium miners: lung cancer risk at low radon exposure rates and modifying effects of time since exposure and age at exposure

International Nuclear Information System (INIS)

Ladislav Tomasek; Agnes Rogel; Margot Tirmarche; Dominique Laurier

2006-01-01

The present analysis was conducted in the frame of European project 'Quantification of lung cancer risk after low radon exposure and low exposure rate: synthesis from epidemiologic and experimental data'. The overall goal of the project related to uranium miners was the evaluation of lung cancer dose-response relationship and of dose rate effects among European uranium miners exposed to low doses and low dose rates of radon decay products. In addition, modifying factors like attained age, age at exposure and time since exposure were investigated. The joint analysis of French and Czech uranium miners was conducted mainly in order to increase the statistical power and to allow a more detailed description of the variation of dose-response relationship in time. (N.C.)

Joint analysis of French and Czech uranium miners: lung cancer risk at low radon exposure rates and modifying effects of time since exposure and age at exposure

Energy Technology Data Exchange (ETDEWEB)

Ladislav Tomasek [National Radiation Protection Institute, Prague (Czech Republic); Agnes Rogel; Margot Tirmarche; Dominique Laurier [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France)

2006-07-01

The present analysis was conducted in the frame of European project 'Quantification of lung cancer risk after low radon exposure and low exposure rate: synthesis from epidemiologic and experimental data'. The overall goal of the project related to uranium miners was the evaluation of lung cancer dose-response relationship and of dose rate effects among European uranium miners exposed to low doses and low dose rates of radon decay products. In addition, modifying factors like attained age, age at exposure and time since exposure were investigated. The joint analysis of French and Czech uranium miners was conducted mainly in order to increase the statistical power and to allow a more detailed description of the variation of dose-response relationship in time. (N.C.)

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)

Effects in Plant Populations Resulting from Chronic Radiation Exposure

Energy Technology Data Exchange (ETDEWEB)

Geras' kin, Stanislav A.; Volkova, Polina Yu.; Vasiliyev, Denis V.; Dikareva, Nina S.; Oudalova, Alla A. [Russian Institute of Agricultural Radiology and Agroecology, 249032, Obninsk (Russian Federation)

2014-07-01

Human industrial activities have left behind a legacy of ecosystems strongly impacted by a wide range of contaminants, including radionuclides. Phyto-toxic effects of acute impact are well known, but the consequences of long-term chronic exposure to low pollutant concentrations is neither well understood nor adequately included in risk assessments. To understand effects of real-world contaminant exposure properly we must pay attention to what is actually going on in the field. However, for many wildlife groups and endpoints, there are no, or very few, studies that link accumulation, chronic exposure and biological effects in natural settings. To fill the gaps, results of field studies carried out on different plant species (winter rye and wheat, spring barley, oats, Scots pine, wild vetch, crested hair-grass) in various radioecological situations (nuclear weapon testing, the Chernobyl accident, uranium and radium processing) to investigate effects of long-term chronic exposure to radionuclides are discussed. Because each impacted site developed in its own way due to a unique history of events, the experience from one case study is rarely directly applicable to another situation. In spite of high heterogeneity in response, we have detected several general patterns. Plant populations growing in areas with relatively low levels of pollution are characterized by the increased level of both cytogenetic alterations and genetic diversity. Accumulation of cellular alterations may afterward influence biological parameters important for populations such as health and reproduction. Presented data provide evidence that in plant populations inhabiting heavily contaminated territories cytogenetic damage were accompanied by decrease in reproductive ability. In less contaminated sites, because of the scarcity of data available, it is impossible to establish exactly the relationship between cytogenetic effects and reproductive ability. Radioactive contamination of the plants

Acute and chronic toxicity of uranium compounds to Ceriodaphnia-Daphnia dubia

International Nuclear Information System (INIS)

Pickett, J.B.; Specht, W.L.; Keyes, J.L.

1993-01-01

A study to determine the acute and chronic toxicity of uranyl nitrate, hydrogen uranyl phosphate, and uranium dioxide to the organism Ceriodaphnia dubia was conducted. The toxicity tests were conducted by two independent environmental consulting laboratories. Part of the emphasis for this determination was based on concerns expressed by SCDHEC, which was concerned that a safety factor of 100 must be applied to the previous 1986 acute toxicity result of 0.22 mg/L for Daphnia pulex, This would have resulted in the LETF release limits being based on an instream concentration of 0.0022 mg/L uranium. The NPDES Permit renewal application to SCDHEC utilized the results of this study and recommended that the LETF release limit for uranium be based an instream concentration of 0.004 mg/L uranium. This is based on the fact that the uranium releases from the M-Area LETF will be in the hydrogen uranyl phosphate form, or a uranyl phosphate complex at the pH (6--10) of the Liquid Effluent Treatment Facility effluent stream, and at the pH of the receiving stream (5.5 to 7.0). Based on the chronic toxicity of hydrogen uranyl phosphate, a lower uranium concentration limit for the Liquid Effluent Treatment Facility outfall vs. the existing NPDES permit was recommended: The current NPDES permit ''Guideline'' for uranium at outfall M-004 is 0.500 mg/L average and 1.0 mg/L maximum, at a design flowrate of 60 gpm. It was recommended that the uranium concentration at the M-004 outfall be reduced to 0.28 mg/L average, and 0.56 mg/L, maximum, and to reduce the design flowrate to 30 gpm. The 0.28 mg/L concentration will provide an instream concentration of 0.004 mg/L uranium. The 0.28 mg/L concentration at M-004 is based on the combined flows from A-014, A-015, and A-011 outfalls (since 1985) of 1840 gpm (2.65 MGD) and was the flow rate which was utilized in the 1988 NPDES permit renewal application

Development of lesions in Syrian golden hamsters following exposure to radon daughters and uranium ore dust

International Nuclear Information System (INIS)

Cross, F.T.; Palmer, R.F.; Busch, R.H.; Filipy, R.E.; Stuart, B.O.

1981-01-01

The development of lesions in Syrian Golden hamsters was studied following life-span inhalation exposures to radon, radon daughters and uranium ore dust. Clinical measurements revealed that life-span exposures to radon daughters and uranium ore dust, singly or in combination, caused no significant changes in mortality patterns, body weights or hematological parameters compared with controls. Pulmonary and nonpulmonary lesions are presented. Exposure to uranium ore dust provoked inflammatory and proliferative responses in the lungs consisting of macrophage accumulation, alveolar cell hyperplasia, and adenomatous alteration of alveolar epithelium. The adenomatous lesions did not undergo further morphologic change. Exposure to radon and radon daughters was associated with increased occurrence of bronchiolar epithelial hyperplasia and with metaplastic changes of alveolar epithelium. Squamous carcinoma developed in only a few hamsters and only in those animals receiving radon daughter exposures exceeding 8000 WLM. It is concluded that an animal model other than the hamster would be more appropriate for study of the pulmonary carcinogenic potential of uranium ore alone. (author)

Uranium: properties and biological effects after internal contamination

International Nuclear Information System (INIS)

Souidi, M.; Tissandie, E.; Racine, R.; Ben Soussan, H.; Rouas, C.; Grignard, E.; Dublineau, I.; Gourmelon, P.; Lestaevel, P.; Gueguen, Y.

2009-01-01

Uranium is a radionuclide present in the environment since the origin of the Earth. In addition to natural uranium, recent deposits from industrial or military activities are acknowledged. Uranium's toxicity is due to a combination of its chemical (heavy metal) and radiological properties (emission of ionizing radiations). Acute toxicity induces an important weight loss and signs of renal and cerebral impairment. Alterations of bone growth, modifications of the reproductive system and carcinogenic effects are also often seen. On the contrary, the biological effects of a chronic exposure to low doses are unwell known. However, results from different recent studies suggest that a chronic contamination with low levels of uranium induces subtle but significant levels. Indeed, an internal contamination of rats for several weeks leads to detection of uranium in many cerebral structures, in association with an alteration of short-term memory and an increase of anxiety level. Biological effects of uranium on the metabolisms of xenobiotics, steroid hormones and vitamin D were described in the liver, testis and kidneys. These recent scientific data suggest that uranium could participate to increase of health risks linked to environmental pollution. (authors)

Exposure pathways and health effects associated with chemical and radiological toxicity of natural uranium: a review.

Science.gov (United States)

Brugge, Doug; de Lemos, Jamie L; Oldmixon, Beth

2005-01-01

Natural uranium exposure derives from the mining, milling, and processing of uranium ore, as well as from ingestion of groundwater that is naturally contaminated with uranium. Ingestion and inhalation are the primary routes of entry into the body. Absorption of uranium from the lungs or digestive track is typically low but can vary depending on compound specific solubility. From the blood, two-thirds of the uranium is excreted in urine over the first 24 hours and up to 80% to 90% of uranium deposited in the bone leaves the body within 1.5 years. The primary health outcomes of concern documented with respect to uranium are renal, developmental, reproductive, diminished bone growth, and DNA damage. The reported health effects derive from experimental animal studies and human epidemiology. The Lowest Observed Adverse Effect Level (LOAEL) derived from animal studies is 50 microg/m3 for inhalation and 60 ug/kg body weight/day for ingestion. The current respiratory standard of the Occupational Safety and Health Administration (OSHA), 50 microg/m3, affords no margin of safety. Considering the safety factors for species and individual variation, the ingestion LOAEL corresponds to the daily consumption set by the World Health Organization Drinking Water Standard at 2 microg/L. Based on economic considerations, the United States Environmental Protection Agency maximum contaminant level is 30 microg/L. Further research is needed, with particular attention on the impact of uranium on indigenous populations, on routes of exposure in communities near uranium sites, on the combined exposures present at many uranium sites, on human developmental defects, and on health effects at or below established exposure standards.

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)

An incident study about acute and chronic human exposure to uranium by high-resolution inductively coupled plasma mass spectrometry (HR-ICPMS)

NARCIS (Netherlands)

Krystek, Petra; Ritsema, Rob

2008-01-01

From the year 2003 to 2005 around 1700 Dutch soldiers made a part of the international stabilisation force in Iraq. An incident happened as a group of four Dutch soldiers found a 30 mm bullet identified as containing depleted uranium (DU). The main pathway of the acute exposure is via inhalation of

Uranium Mining and Norm in North America-Some Perspectives on Occupational Radiation Exposure.

Science.gov (United States)

Brown, Steven H; Chambers, Douglas B

2017-07-01

All soils and rocks contain naturally occurring radioactive materials (NORM). Many ores and raw materials contain relatively elevated levels of natural radionuclides, and processing such materials can further increase the concentrations of naturally occurring radionuclides. In the U.S., these materials are sometimes referred to as technologically-enhanced naturally occurring radioactive materials (TENORM). Examples of NORM minerals include uranium ores, monazite (a source of rare earth minerals), and phosphate rock used to produce phosphate fertilizer. The processing of these materials has the potential to result in above-background radiation exposure to workers. Following a brief review of the sources and potential for worker exposure from NORM in these varied industries, this paper will then present an overview of uranium mining and recovery in North America, including discussion on the mining methods currently being used for both conventional (underground, open pit) and in situ leach (ISL), also referred to as In Situ Recovery (ISR), and the production of NORM materials and wastes associated with these uranium recovery methods. The radiological composition of the NORM products and wastes produced and recent data on radiological exposures received by workers in the North American uranium recovery industry are then described. The paper also identifies the responsible government agencies in the U.S. and Canada assigned the authority to regulate and control occupational exposure from these NORM materials.

Occupational Exposures and Chronic Airflow Limitation

Directory of Open Access Journals (Sweden)

Helen Dimich-Ward

1996-01-01

Full Text Available The recent literature was reviewed to evaluate whether chronic airflow limitation is associated with occupational exposures to dusts. Only those studies that controlled for the effects of smoking were included. There is compelling evidence that exposure to inorganic dusts, such as from coal and hardrock mining or asbestos, are associated with the development of chronic airflow limitation, independently of pneumoconiosis. Nonsmoking gold miners are particularly at high risk of airflow obstruction and emphysema. Findings from studies of organic dusts, such as exposures to wood, cotton, grain or other agricultural dusts, or to mixed dust exposures, were less consistent but tended to show positive dose-response associations. In the majority of studies, no statistical interaction was shown between dust exposures and smoking; however, the effects of the dust exposures were often more pronounced. An occupational history should be considered, in addition to a smoking history, as an integral part of an investigation of chronic airflow limitation in a patient.

Induction of oxidative stress related responses in Arabidopsis thaliana after uranium exposure

International Nuclear Information System (INIS)

Vanhoudt, N.

2009-01-01

Uranium contamination in the environment has resulted from releases linked with nuclear fuel cycle activities and from industries extracting and processing materials containing naturally occurring radionuclides (for example phosphate industry). Uranium toxicity effects are predominantly studied on man and animal species, but little information is available for plants. If phytomanagement of uranium contaminated soils is considered, biological effects on the vegetation have to be investigated. Information on the contamination impact can also be used for risk assessment and derivation of clean-up standards. Plants can experience oxidative stress when they are exposed to environmental stress situations (for example exposure to heavy metals). Reactive oxygen species (ROS) are produced in both stressed and unstressed cells potentially leading to cellular damage. Consequently, plants have developed an antioxidative defence system comprising ROS-scavenging enzymes (e.g. SOD (superoxide dismutase), CAT (catalase) and metabolites (e.g. ascorbate, glutathione). Previous results showed that uranium exposure can cause an imbalance between the oxidative and antioxidative capacities of the plant cells. The present study aimed to analyse biological effects induced in Arabidopsis thaliana after bioaccumulation of uranium and to define possible dose-effect relationships. Subtle effects on the antioxidative defence system (enzymes, metabolites viewed as early responses for individual disturbances (growth, nutrient profile) were analysed

Chronic exposure to uranium compounds: medical surveillance problems related to their physico-chemical properties and their solubility: actual data and future prospects

International Nuclear Information System (INIS)

Ansoborlo, E.; Chalabreysse, J.C.

1988-01-01

A method was developped to assess uranium exposure hazards at work stations based on industrial experience acquired in Comurhex Malvesi at Narbonne. Applied to uranium tetrafluoride (UF4), the method involves five steps: 1/ Characterization of the industrial compound, including physico-chemical properties (density, surface area, X-ray spectrum and uranium enrichment). 2/ In vitro biological solubility with different synthetic fluids like Gamble solution added with differents gaz or compounds (Oxygen or hydrogen peroxyde), in order to determine the solubility class D, W or Y. 3/ Assessment of work station concentration in Bq m -3 and particle size distribution (AMAD). 4/ Monitoring workers by routine urinary excretion completed, if necessary, by fecal excretion and γ spectrometry. 5/ Use of individual protection filters or masks. Results and actual data on UF4 are presented and future prospects of studies on calcinated uranates are dealed with [fr

Non-neoplastic pulmonary disease from inhaled radon daughters with uranium ore dust in beagle dogs

International Nuclear Information System (INIS)

Filipy, R.E.; Palmer, R.F.; Stuart, B.O.

1977-01-01

Daily exposures of adult beagle dogs to inhaled radon daughters plus uranium ore dust, with and without concurrent cigarette smoking, for 2 to 5-1/2 yr have produced massive pulmonary fibrosis and severe emphysema. The cumulative exposure doses are similar to those associated with a 5-fold or greater increase in death rate of uranium miners due to chronic respiratory insufficiency, including pneumoconiosis, pulmonary fibrosis, and emphysema

Cross-sectional study of uranium mine workers to develop predictive equations for lung functions with reference to chronic obstructive pulmonary disease

Energy Technology Data Exchange (ETDEWEB)

De Kock, M A [Stellenbosch Univ. (South Africa); Swiegers, W R.S. [Roessing Uranium Mine, Swakopmund (South West Africa/Namibia); Kotze, T J.v.W.; Joubert, G [South African Medical Research Council, Cape Town (South Africa)

1988-03-19

As the first part of a prospective epidemiological study of the lung function and dust exposure of workers at the Roessing Uranium Mine in SWA/Namibia, various measurements of lung function of 1407 workers were carried out. This was necessary in order to follow up any chronic obstructive pulmonary disease that might develop. The opportunity was used to test existing prediction formulae and to develop formulae for normal values for workers at the Roessing mine. 94 refs., 36 figs., 14 tabs.

Cross-sectional study of uranium mine workers to develop predictive equations for lung functions with reference to chronic obstructive pulmonary disease

International Nuclear Information System (INIS)

De Kock, M.A.; Swiegers, W.R.S.; Kotze, T.J.v.W.; Joubert, G.

1988-01-01

As the first part of a prospective epidemiological study of the lung function and dust exposure of workers at the Roessing Uranium Mine in SWA/Namibia, various measurements of lung function of 1 407 workers were carried out. This was necessary in order to follow up any chronic obstructive pulmonary disease that might develop. The opportunity was used to test existing prediction formulae and to develop formulae for normal values for workers at the Roessing mine. 94 refs., 36 figs., 14 tabs

Enriched but not depleted uranium affects central nervous system in long-term exposed rat.

Science.gov (United States)

Houpert, Pascale; Lestaevel, Philippe; Bussy, Cyrill; Paquet, François; Gourmelon, Patrick

2005-12-01

Uranium is well known to induce chemical toxicity in kidneys, but several other target organs, such as central nervous system, could be also affected. Thus in the present study, the effects on sleep-wake cycle and behavior were studied after chronic oral exposure to enriched or depleted uranium. Rats exposed to 4% enriched uranium for 1.5 months through drinking water, accumulated twice as much uranium in some key areas such as the hippocampus, hypothalamus and adrenals than did control rats. This accumulation was correlated with an increase of about 38% of the amount of paradoxical sleep, a reduction of their spatial working memory capacities and an increase in their anxiety. Exposure to depleted uranium for 1.5 months did not induce these effects, suggesting that the radiological activity induces the primary events of these effects of uranium.

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

Biological pathways of exposure and ecotoxicity values for uranium and associated radionuclides: Chapter D in Hydrological, geological, and biological site characterization of breccia pipe uranium deposits in Northern Arizona

Science.gov (United States)

Hinck, Jo E.; Linder, Greg L.; Finger, Susan E.; Little, Edward E.; Tillitt, Donald E.; Kuhne, Wendy

2010-01-01

This chapter compiles available chemical and radiation toxicity information for plants and animals from the scientific literature on naturally occurring uranium and associated radionuclides. Specifically, chemical and radiation hazards associated with radionuclides in the uranium decay series including uranium, thallium, thorium, bismuth, radium, radon, protactinium, polonium, actinium, and francium were the focus of the literature compilation. In addition, exposure pathways and a food web specific to the segregation areas were developed. Major biological exposure pathways considered were ingestion, inhalation, absorption, and bioaccumulation, and biota categories included microbes, invertebrates, plants, fishes, amphibians, reptiles, birds, and mammals. These data were developed for incorporation into a risk assessment to be conducted as part of an environmental impact statement for the Bureau of Land Management, which would identify representative plants and animals and their relative sensitivities to exposure of uranium and associated radionuclides. This chapter provides pertinent information to aid in the development of such an ecological risk assessment but does not estimate or derive guidance thresholds for radionuclides associated with uranium. Previous studies have not attempted to quantify the risks to biota caused directly by the chemical or radiation releases at uranium mining sites, although some information is available for uranium mill tailings and uranium mine closure activities. Research into the biological impacts of uranium exposure is strongly biased towards human health and exposure related to enriched or depleted uranium associated with the nuclear energy industry rather than naturally occurring uranium associated with uranium mining. Nevertheless, studies have reported that uranium and other radionuclides can affect the survival, growth, and reproduction of plants and animals. Exposure to chemical and radiation hazards is influenced by a

Occupational exposure and mortality in the German uranium miner cohort

International Nuclear Information System (INIS)

Schnelzer, M.; Dufey, F.; Grosche, B.; Sogl, M.; Tschense, A.; Walsh, L.; Kreuzer, M.

2014-01-01

The German uranium miners cohort study comprises 58,982 men employed in the GDR by the Wismut company for at least six months between 1946 and 1989. Particularly in the early years, miners were exposed to high levels of radon, silica and other harmful substances. The aim of the cohort study is to investigate the health effects of occupational exposures. The cohort was established in 1998 with mortality follow-ups every five years, i.e. vital status and cause of death are ascertained. Annual exposures to radon progeny, external gamma-radiation, long-lived radionuclides, fine dust, silica and arsenic dust were individually assessed by means of a comprehensive job-exposure matrix. For data analyses Poisson regression models were used. By end of 2008, 25,438 (43 %) cohort members were deceased with known cause of death in 94 %. In total 7,780 cancer mortalities were observed, including 3,500 from lung cancer. Lung cancer mortality is twice as high as in the general population largely due to occupational radon progeny and silica exposure. Also 975 silicosis deaths were observed and there is some evidence for a relationship between radon progeny exposure and cancers of the extra-thoracic airways. Circulatory diseases and non-malignant diseases of the airways were also investigated, but no relationship to occupational exposure was found. Up to now health effects of uranium mining in the Wismut cohort primarily manifest themselves as increases in lung cancer and silicosis mortality due to high radon progeny and silica exposure. With increasing duration of follow-up, further findings regarding more rare causes of death and levels of exposure relevant today are expected.

Molecular, cellular, and tissue impact of depleted uranium on xenobiotic-metabolizing enzymes.

Science.gov (United States)

Gueguen, Yann; Rouas, Caroline; Monin, Audrey; Manens, Line; Stefani, Johanna; Delissen, Olivia; Grison, Stéphane; Dublineau, Isabelle

2014-02-01

Enzymes that metabolize xenobiotics (XME) are well recognized in experimental models as representative indicators of organ detoxification functions and of exposure to toxicants. As several in vivo studies have shown, uranium can alter XME in the rat liver or kidneys after either acute or chronic exposure. To determine how length or level of exposure affects these changes in XME, we continued our investigation of chronic rat exposure to depleted uranium (DU, uranyl nitrate). The first study examined the effect of duration (1-18 months) of chronic exposure to DU, the second evaluated dose dependence, from a level close to that found in the environment near mining sites (0.2 mg/L) to a supra-environmental dose (120 mg/L, 10 times the highest level naturally found in the environment), and the third was an in vitro assessment of whether DU exposure directly affects XME and, in particular, CYP3A. The experimental in vivo models used here demonstrated that CYP3A is the enzyme modified to the greatest extent: high gene expression changed after 6 and 9 months. The most substantial effects were observed in the liver of rats after 9 months of exposure to 120 mg/L of DU: CYP3A gene and protein expression and enzyme activity all decreased by more than 40 %. Nonetheless, no direct effect of DU by itself was observed after in vitro exposure of rat microsomal preparations, HepG2 cells, or human primary hepatocytes. Overall, these results probably indicate the occurrence of regulatory or adaptive mechanisms that could explain the indirect effect observed in vivo after chronic exposure.

In vivo effects of a chronic contamination by uranium or cesium 137 on the pharmaceutical metabolism, of the vitamin D and cholesterol; Effets in vivo d'une contamination chronique par l'uranium ou le cesium 137 sur le metabolisme du medicament, de la vitamine D et du cholesterol

Energy Technology Data Exchange (ETDEWEB)

Souidi, M

2006-11-15

In conclusion, an animal model, miming the chronic contamination of the populations exposed to the uranium, was used for the first time to show that the chronic ingestion of a weak dose of depleted uranium can affect the level of active vitamin D without modifying the mineral homeostasis. This study shows that this radionuclide can lead molecular modifications of the CYPs and the nuclear receivers involved in the metabolism of the vitamin D not only at the level of the liver and kidney but also at the level of the independent metabolism in the brain. The deficiency in vitamin D can provoke osseous diseases such as the rickets at the child and the osteomalacia at the adult. The three categories of population the most exposed to this deficiency are the infants, the pregnant women and the old persons. Strong prevalence of the vitamin D deficiency associated with a chronic exposure to uranium could lead to osseous disorders. To verify this hypothesis, it will be necessary secondly to realize this study on individuals animal models predisposed to the rickets or to the osteomalacia. (N.C.)

Cerebral cortex and hippocampus respond differently after post-natal exposure to uranium

International Nuclear Information System (INIS)

Lestaevel, Philippe; Bensoussan, Hélène; Dhieux, Bernadette; Delissen, Olivia; Dublineau, Isabelle; Voisin, Philippe; Vacher, Claire-Marie; Taouis, Mohammed

2013-01-01

The central nervous system (CNS) is known to be sensitive to pollutants during its development. Uranium (U) is a heavy metal that occurs naturally in the environment as a component of the earth's crust, and populations may therefore be chronically exposed to U through drinking water and food. Previous studies have shown that the CNS is a target of U in rats exposed in adulthood. We assessed the effects of U on behavior and cholinergic system of rats exposed from birth for 10 weeks at 10 mg.L"-"1 or 40 mg.L"-"1. For behavioral analysis, the sleep/wake cycle (recorded by telemetry), the object recognition memory and the spatial working memory (Y-maze) were evaluated. Acetylcholine (ACh) and acetylcholinesterase (AChE) levels were evaluated in the entorhinal cortex and hippocampus. At 40 mg.L"-"1, U exposure impaired object recognition memory (-20%), but neither spatial working memory nor the sleep/wake cycle was impaired. A significant decrease was observed in both the ACh concentration (-14%) and AChE activity (-14%) in the entorhinal cortex, but not in the hippocampus. Any significant effect on behaviour and cholinergic system was observed at 10 mg U.L"-"1. These results demonstrate that early exposure to U during postnatal life induces a structure cerebral-dependant cholinergic response and modifies such memory process in rats. This exposure to U early in life could have potential delayed effects in adulthood. (author)

Mortality from internal and external radiation exposure in a cohort of male German uranium millers, 1946-2008

Energy Technology Data Exchange (ETDEWEB)

Kreuzer, M.; Dufey, F.; Schnelzer, M.; Sogl, M.; Walsh, L. [Federal Office for Radiation Protection, Neuherberg (Germany). Dept. of Radiation Protection and Health; Laurier, D. [Institute for Radiological Protection and Nuclear Safety (IRSN), Paris (France); Nowak, D. [LMU Muenchen (Germany). Inst. for Occupational Medicine and Environmental Medicine; Marsh, J.W. [Public Health England, Chilton, Didcot (United Kingdom)

2015-05-15

To examine exposure-response relationships between ionizing radiation and several mortality outcomes in a subgroup of 4,054 men of the German uranium miner cohort study, who worked between 1946 and 1989 in milling facilities, but never underground or in open pit mines. Mortality follow-up was from 1946 to 2008, accumulating 158,383 person-years at risk. Cumulative exposure to radon progeny in working level months (WLM) (mean = 8, max = 127), long-lived radionuclides from uranium ore dust in kBqh/m{sup 3} (mean = 3.9, max = 132), external gamma radiation in mSv (mean = 26, max = 667) and silica dust was estimated by a comprehensive job-exposure matrix. Internal Poisson regression models were applied to estimate the linear excess relative risk (ERR) per unit of cumulative exposure. Overall, a total of 457, 717 and 111 deaths occurred from malignant cancer, cardiovascular diseases and non-malignant respiratory diseases, respectively. Uranium ore dust and silica dust were not associated with mortality from any of these disease groups. A statistically significant relationship between cumulative radon exposure and mortality from all cancers (ERR/100 WLM = 1.71; p = 0.02), primarily due to lung cancer (n = 159; ERR/100 WLM = 3.39; p = 0.05), was found. With respect to cumulative external gamma radiation, an excess of mortality of solid cancers (n = 434; ERR/Sv = 1.86; p = 0.06), primarily due to stomach cancer (n = 49, ERR/Sv = 10.0; p = 0.12), was present. The present findings show an excess mortality from lung cancer due to radon exposure and from solid cancers due to external gamma radiation in uranium millers that was not statistically significant. Exposure to uranium was not associated with any cause of death, but absorbed organ doses were estimated to be low.

Mortality from internal and external radiation exposure in a cohort of male German uranium millers, 1946-2008

International Nuclear Information System (INIS)

Kreuzer, M.; Dufey, F.; Schnelzer, M.; Sogl, M.; Walsh, L.; Nowak, D.

2015-01-01

To examine exposure-response relationships between ionizing radiation and several mortality outcomes in a subgroup of 4,054 men of the German uranium miner cohort study, who worked between 1946 and 1989 in milling facilities, but never underground or in open pit mines. Mortality follow-up was from 1946 to 2008, accumulating 158,383 person-years at risk. Cumulative exposure to radon progeny in working level months (WLM) (mean = 8, max = 127), long-lived radionuclides from uranium ore dust in kBqh/m 3 (mean = 3.9, max = 132), external gamma radiation in mSv (mean = 26, max = 667) and silica dust was estimated by a comprehensive job-exposure matrix. Internal Poisson regression models were applied to estimate the linear excess relative risk (ERR) per unit of cumulative exposure. Overall, a total of 457, 717 and 111 deaths occurred from malignant cancer, cardiovascular diseases and non-malignant respiratory diseases, respectively. Uranium ore dust and silica dust were not associated with mortality from any of these disease groups. A statistically significant relationship between cumulative radon exposure and mortality from all cancers (ERR/100 WLM = 1.71; p = 0.02), primarily due to lung cancer (n = 159; ERR/100 WLM = 3.39; p = 0.05), was found. With respect to cumulative external gamma radiation, an excess of mortality of solid cancers (n = 434; ERR/Sv = 1.86; p = 0.06), primarily due to stomach cancer (n = 49, ERR/Sv = 10.0; p = 0.12), was present. The present findings show an excess mortality from lung cancer due to radon exposure and from solid cancers due to external gamma radiation in uranium millers that was not statistically significant. Exposure to uranium was not associated with any cause of death, but absorbed organ doses were estimated to be low.

Canine neoplasia and exposure to uranium mill tailings in Mesa County, Colorado

International Nuclear Information System (INIS)

Reif, J.S.; Schweitzer, D.J.; Ferguson, S.W.; Benjamin, S.A.

1983-01-01

A canine cancer registry was established for Mesa County, Colorado in order to collect material for a case control analysis of exposure to uranium tailings. Between 1979 and 1981, 212 cases of canine cancer were confirmed histologically. Based on the address provided at the time of diagnosis, 33 dogs (15.6%) lived in a house with some exposure to uranium tailings. A control group, comprised of dogs with a histologic diagnosis other than cancer, was stratified according to hospital and matched with cases on a 1:1 basis. No significant differences were noted with respect to exposure to uranium tailings for total cancers or cancers of specific sites including lymph node, breast, liver, testicle and bone. The overall estimated relative risk was 0.70 (95% CI 0.04 to 1.16). Canine population estimates were derived for Mesa County in order to develop crude incidence rates for the major types and sites of cancer. Crude rates were compared with those published previously for Alameda County, California and Tulsa County, Oklahoma. Mesa County rates for total cancer incidence, connective tissue tumors and non melanoma skin cancer were higher than those reported for Alameda County. When compared with Tulsa County, Mesa County rates for total cancer, breast cancer, melanoma and mastocytoma were lower than expected while rates for osteosarcoma, hemangiosarcoma and fibrosarcoma significantly exceeded expected values

Analytical developments for the speciation of uranium in zebra fish (Danio rerio) gills after exposure

International Nuclear Information System (INIS)

Bucher, Guillaume

2013-01-01

The objective of this thesis is to study the cellular compartmentalization and the chelation of uranium (U) by cytosolic proteins of gill cells of the zebra fish (Danio rerio, model specie in aquatic toxicology) under different direct exposure conditions (chronic vs. acute, 20 and 250 μg.L -1 ). This study required the development of hyphenated techniques (SEC, IEF off-gel, RP-UHPLC for the separation, ICP-SFMS, ESI-FTMS/MS for the detection) with the main challenges of maintaining the non-covalent U-biomolecule interactions and enhancing sensitivity for the analysis of environmentally relevant samples. After extraction, 24% to 32% of the total U detected in the gills were present in the cytosolic fraction, in which the U distribution on the biomolecules (as a function of their MW and pI) varied depending on the exposure level. Finally, U target biomolecules mapping allowed us (i) to highlight a particular affinity of U for acidic and/or P-containing proteins and (ii) to identify 24 protein candidates for U binding. (author) [fr

Chronic plus binge ethanol exposure causes more severe pancreatic injury and inflammation

Energy Technology Data Exchange (ETDEWEB)

Ren, Zhenhua [Department of Anatomy, School of Basic Medicine, Anhui Medical University, Hefei, Anhui, China 230032 (China); Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Yang, Fanmuyi; Wang, Xin; Wang, Yongchao; Xu, Mei; Frank, Jacqueline A. [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Ke, Zun-ji [Department of Biochemistry, Shanghai University of Traditional Chinese Medicine, Shanghai 201203 (China); Zhang, Zhuo; Shi, Xianglin [Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Luo, Jia, E-mail: jialuo888@uky.edu [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States)

2016-10-01

Alcohol abuse increases the risk for pancreatitis. The pattern of alcohol drinking may impact its effect. We tested a hypothesis that chronic ethanol consumption in combination with binge exposure imposes more severe damage to the pancreas. C57BL/6 mice were divided into four groups: control, chronic ethanol exposure, binge ethanol exposure and chronic plus binge ethanol exposure. For the control group, mice were fed with a liquid diet for two weeks. For the chronic ethanol exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks. In the binge ethanol exposure group, mice were treated with ethanol by gavage (5 g/kg, 25% ethanol w/v) daily for 3 days. For the chronic plus binge exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks and exposed to ethanol by gavage during the last 3 days. Chronic and binge exposure alone caused minimal pancreatic injury. However, chronic plus binge ethanol exposure induced significant apoptotic cell death. Chronic plus binge ethanol exposure altered the levels of alpha-amylase, glucose and insulin. Chronic plus binge ethanol exposure caused pancreatic inflammation which was shown by the macrophages infiltration and the increase of cytokines and chemokines. Chronic plus binge ethanol exposure increased the expression of ADH1 and CYP2E1. It also induced endoplasmic reticulum stress which was demonstrated by the unfolded protein response. In addition, chronic plus binge ethanol exposure increased protein oxidation and lipid peroxidation, indicating oxidative stress. Therefore, chronic plus binge ethanol exposure is more detrimental to the pancreas. - Highlights: • Chronic plus binge alcohol drinking causes more pancreatic injury. • Chronic plus binge alcohol drinking induces more pancreatic inflammation. • Chronic plus binge alcohol causes more endoplasmic reticulum stress and oxidative stress.

Chronic plus binge ethanol exposure causes more severe pancreatic injury and inflammation

International Nuclear Information System (INIS)

Ren, Zhenhua; Yang, Fanmuyi; Wang, Xin; Wang, Yongchao; Xu, Mei; Frank, Jacqueline A.; Ke, Zun-ji; Zhang, Zhuo; Shi, Xianglin; Luo, Jia

2016-01-01

Alcohol abuse increases the risk for pancreatitis. The pattern of alcohol drinking may impact its effect. We tested a hypothesis that chronic ethanol consumption in combination with binge exposure imposes more severe damage to the pancreas. C57BL/6 mice were divided into four groups: control, chronic ethanol exposure, binge ethanol exposure and chronic plus binge ethanol exposure. For the control group, mice were fed with a liquid diet for two weeks. For the chronic ethanol exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks. In the binge ethanol exposure group, mice were treated with ethanol by gavage (5 g/kg, 25% ethanol w/v) daily for 3 days. For the chronic plus binge exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks and exposed to ethanol by gavage during the last 3 days. Chronic and binge exposure alone caused minimal pancreatic injury. However, chronic plus binge ethanol exposure induced significant apoptotic cell death. Chronic plus binge ethanol exposure altered the levels of alpha-amylase, glucose and insulin. Chronic plus binge ethanol exposure caused pancreatic inflammation which was shown by the macrophages infiltration and the increase of cytokines and chemokines. Chronic plus binge ethanol exposure increased the expression of ADH1 and CYP2E1. It also induced endoplasmic reticulum stress which was demonstrated by the unfolded protein response. In addition, chronic plus binge ethanol exposure increased protein oxidation and lipid peroxidation, indicating oxidative stress. Therefore, chronic plus binge ethanol exposure is more detrimental to the pancreas. - Highlights: • Chronic plus binge alcohol drinking causes more pancreatic injury. • Chronic plus binge alcohol drinking induces more pancreatic inflammation. • Chronic plus binge alcohol causes more endoplasmic reticulum stress and oxidative stress.

UDAD, Radiation Exposure to Man at Uranium Processing Plant

International Nuclear Information System (INIS)

Momeni, M.H.; Yuan, Y.; Zielen, A.J.

1983-01-01

1 - Description of problem or function: The Uranium Dispersion and Dosimetry (UDAD) program provides estimates of potential radiation exposure to individuals and to the general population in the vicinity of a uranium processing facility such as a uranium mine or mill. Only transport through the air is considered. Exposure results from inhalation, external irradiation from airborne and ground- deposited activity, and ingestion of foodstuffs. Individual dose commitments, population dose commitments, and environmental dose commitments are computed. The program was developed for application to uranium mining and milling; however, it may be applied to dispersion of any other pollutant. 2 - Method of solution: The removal of radioactive particles from a contaminated area such as uranium tailings by wind action is estimated from theoretical and empirical wind-erosion equations according to the wind speed, particle size distribution, surface roughness, and other parameters. Atmospheric concentrations of radioactivity from specific sources are calculated by means of a dispersion-deposition-resuspension model. Source depletion as a result of deposition, fallout of the heavier particulates, and radioactive decay and ingrowth of radon daughters are included in a sector-averaged, Gaussian plume dispersion model. The average air concentration at any given receptor location is assumed to be constant during each annual release period, but to increase from year to year because of resuspension. Surface contamination is estimated by including buildup from deposition, ingrowth of radio- active daughters, and removal by radioactive decay, weathering, and other environmental processes. Deposition velocity is estimated on the basis of particle size, density, and physical and chemical environmental conditions which influence the behavior of the smaller particles. Calculation of the inhalation dose to an individual is based on the ICRP Task Group Lung Model (TGLM). Estimates of the dose to

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.

Ultrastructural effects on gill, muscle, and gonadal tissues induced in zebrafish (Danio rerio) by a waterborne uranium exposure

International Nuclear Information System (INIS)

Barillet, Sabrina; Larno, Valerie; Floriani, Magali; Devaux, Alain; Adam-Guillermin, Christelle

2010-01-01

Experiments on adult zebrafish (Danio rerio) were conducted to assess histopathological effects induced on gill, muscle, and gonadal tissues after waterborne uranium exposure. Although histopathology is often employed as a tool for the detection and assessment of xenobiotic-mediated effects in aquatic organisms, few studies have been dedicated to the investigation of histopathological consequences of uranium exposure in fish. Results showed that gill tissue architecture was markedly disrupted. Major symptoms were alterations of the secondary lamellae epithelium (from extensive oedema to desquamation), hyperplasia of chloride cells, and breakdown of the pillar cell system. Muscle histology was also affected. Degeneration and disorganization of myofibrillar sarcomeric pattern as well as abnormal localization of mitochondria within muscle and altered endomysial sheaths were observed. Morphological alterations of spermatozoa within the gonadal tissue were also noticed. This study demonstrated that uranium exposure induced a variety of histological impairments in fish, supporting environmental concerns when uranium contaminates aquatic systems.

Ultrastructural effects on gill, muscle, and gonadal tissues induced in zebrafish (Danio rerio) by a waterborne uranium exposure

Energy Technology Data Exchange (ETDEWEB)

Barillet, Sabrina, E-mail: sabrina.barillet@free.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Larno, Valerie, E-mail: valerie.larno@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Floriani, Magali, E-mail: magali.floriani@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Devaux, Alain, E-mail: alain.devaux@entpe.fr [INRA, EFPA Department, 54280, Champenoux and Environmental Science Laboratory, ENTPE, 69518 Vaulx en Velin cedex (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France)

2010-11-01

Experiments on adult zebrafish (Danio rerio) were conducted to assess histopathological effects induced on gill, muscle, and gonadal tissues after waterborne uranium exposure. Although histopathology is often employed as a tool for the detection and assessment of xenobiotic-mediated effects in aquatic organisms, few studies have been dedicated to the investigation of histopathological consequences of uranium exposure in fish. Results showed that gill tissue architecture was markedly disrupted. Major symptoms were alterations of the secondary lamellae epithelium (from extensive oedema to desquamation), hyperplasia of chloride cells, and breakdown of the pillar cell system. Muscle histology was also affected. Degeneration and disorganization of myofibrillar sarcomeric pattern as well as abnormal localization of mitochondria within muscle and altered endomysial sheaths were observed. Morphological alterations of spermatozoa within the gonadal tissue were also noticed. This study demonstrated that uranium exposure induced a variety of histological impairments in fish, supporting environmental concerns when uranium contaminates aquatic systems.

The effect of exposure to employees from mining and milling operations in a uranium mine on lead isotopes--a pilot study.

Science.gov (United States)

Gulson, Brian L; Mizon, Karen J; Dickson, Bruce L; Korsch, Michael J

2005-03-01

Potential exposure during mining and milling of uranium ore has resulted in the industry being highly regulated. Exposure can arise from inhalation of the daughter product radioactive gas radon (222Rn), inhalation of radioactive dust particles from mining and milling, direct irradiation from outside the body, and ingestion of radionuclides (e.g. uranium or radium) in food or water. Making use of the highly unusual lead isotopic signature for uranium ores (high 206Pb/204Pb from the high uranium content, low 208Pb/204Pb from the low Th/U ratio), we undertook a pilot study of nine male mine employees and three controls from the Ranger uranium mine in the Northern Territory Australia to determine if it was feasible to use lead isotopes in blood to identify exposure to uranium-derived materials. The lead isotopic data for the mine employees and controls plot in two distinct fields which are consistent with predicted isotopic patterns. Assuming retention of 10% of the ingested lead, then the increases seen in 206Pb represent intakes of between 0.9 and 15 mg, integrated over the years of exposure. The small amount of lead does not affect blood lead concentrations, but appears to be sufficient to be detectable with sensitive isotopic methods. Further studies, including those on urine, should be undertaken to confirm the veracity of the lead isotope method in monitoring exposure of uranium industry employees.

The effect of exposure to employees from mining and milling operations in a uranium mine on lead isotopes. A pilot study

International Nuclear Information System (INIS)

Gulson, Brian L.; Mizon, Karen J.; Dickson, Bruce L.; Korsch, Michael J.

2005-01-01

Potential exposure during mining and milling of uranium ore has resulted in the industry being highly regulated. Exposure can arise from inhalation of the daughter product radioactive gas radon ( 222 Rn), inhalation of radioactive dust particles from mining and milling, direct irradiation from outside the body, and ingestion of radionuclides (e.g. uranium or radium) in food or water. Making use of the highly unusual lead isotopic signature for uranium ores (high 206 Pb/ 204 Pb from the high uranium content, low 208 Pb/ 204 Pb from the low Th/U ratio), we undertook a pilot study of nine male mine employees and three controls from the Ranger uranium mine in the Northern Territory Australia to determine if it was feasible to use lead isotopes in blood to identify exposure to uranium-derived materials. The lead isotopic data for the mine employees and controls plot in two distinct fields which are consistent with predicted isotopic patterns. Assuming retention of 10% of the ingested lead, then the increases seen in 206 Pb represent intakes of between 0.9 and 15 mg, integrated over the years of exposure. The small amount of lead does not affect blood lead concentrations, but appears to be sufficient to be detectable with sensitive isotopic methods. Further studies, including those on urine, should be undertaken to confirm the veracity of the lead isotope method in monitoring exposure of uranium industry employees

Exposure pathways and biological receptors: baseline data for the canyon uranium mine, Coconino County, Arizona

Science.gov (United States)

Hinck, Jo E.; Linder, Greg L.; Darrah, Abigail J.; Drost, Charles A.; Duniway, Michael C.; Johnson, Matthew J.; Méndez-Harclerode, Francisca M.; Nowak, Erika M.; Valdez, Ernest W.; van Riper, Charles; Wolff, S.W.

2014-01-01

Recent restrictions on uranium mining within the Grand Canyon watershed have drawn attention to scientific data gaps in evaluating the possible effects of ore extraction to human populations as well as wildlife communities in the area. Tissue contaminant concentrations, one of the most basic data requirements to determine exposure, are not available for biota from any historical or active uranium mines in the region. The Canyon Uranium Mine is under development, providing a unique opportunity to characterize concentrations of uranium and other trace elements, as well as radiation levels in biota, found in the vicinity of the mine before ore extraction begins. Our study objectives were to identify contaminants of potential concern and critical contaminant exposure pathways for ecological receptors; conduct biological surveys to understand the local food web and refine the list of target species (ecological receptors) for contaminant analysis; and collect target species for contaminant analysis prior to the initiation of active mining. Contaminants of potential concern were identified as arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, thallium, uranium, and zinc for chemical toxicity and uranium and associated radionuclides for radiation. The conceptual exposure model identified ingestion, inhalation, absorption, and dietary transfer (bioaccumulation or bioconcentration) as critical contaminant exposure pathways. The biological survey of plants, invertebrates, amphibians, reptiles, birds, and small mammals is the first to document and provide ecological information on .200 species in and around the mine site; this study also provides critical baseline information about the local food web. Most of the species documented at the mine are common to ponderosa pine Pinus ponderosa and pinyon–juniper Pinus–Juniperus spp. forests in northern Arizona and are not considered to have special conservation status by state or federal agencies; exceptions

Background paper for regulations related to the exposure of uranium mine and mill workers

International Nuclear Information System (INIS)

1978-01-01

The Atomic Energy Control Board is modifying the Atomic Energy Control Regulations to include a maximum permissible exposure to radon daughters for uranium mine and mill workers. In January 1976, after consultation with the uranium producers, union, and government regulatory bodies, the AECB issued a directive endorsing a maximum permissible annual occupational exposure to radon daughters of 4 Working Level Months (WLM). This exposure limit was an interim guideline to be applied for at least one year. The Board staff and members of the Mine Safety Advisory Committee have examined available evidence on the excess risk of lung cancer owing to exposure to radon daughters since then, and have assessed the arguments for both raising and lowering the exposure limit. The evidence is still not conclusive, and further studies, especially epidemiological ones, are needed. Nevertheless, the Board considers that the interim guideline is acceptable in the light of the present state of knowledge and that it should be incorporated into the regulations. This document explains why the Board has made this decision and discusses a number of related issues

In vivo measurements of lead-210 for assessing cumulative radon exposure in uranium miners

International Nuclear Information System (INIS)

Guilmette, R.A.; Laurer, G.R.; Lambert, W.E.; Gilliland, F.D.

1995-01-01

It has long been recognized that a major contributor to the uncertainty in risk analysis of lung cancer in uranium and other hard rock miners is the estimation of total radon progeny exposure of individual miners under study. These uncertainties arise from the fact that only a limited number of measurements of airborne 222 Rn progeny concentrations were made in the mines during the times that the miners were being exposed, and that dosimeters capable of integrating the Rn progeny exposures of the miners did not exist. Historically, the cumulative exposures for individual uranium and other hard rock miners have been calculated by combining the employee's work history, which may or may not have included time spent at different jobs within the mines and at different locations within the mines, with whatever periodic measurements of Rn and Rn progeny were available. The amount and quality of the measurement data varied enormously from mine to mine and from population to population. Because the quality of the exposure data collected during the period of active mining in the United STates cannot now be altered substantially, significant improvement in individual miner exposure estimates is only likely to be achieved if a new cumulative exposure metric is developed and implemented. The decay chain of Rn includes the production of 210 Pb, which can accumulate in the skeleton in amounts proportional to the intake of Rn progeny. We hypothesize that the in vivo measurement of 210 Pb in the skulls of miners will provide such a metric. In summary, the primary purpose of this pilot study to demonstrate the feasibility of measuring 210 Pb in the heads of former uranium miners has been accomplished

Radiation exposure of the Bulgarian population exceeding the background as a result of mining and processing of uranium ores

International Nuclear Information System (INIS)

Yonchev, L.; Vasilev, G.

1999-01-01

The nearly 50-year-long history of researches, mining and processing and closure of uranium industry of researches, mining and processing and the closure of uranium industry sites in the country as well necessitate reassessment of the radiation exposure of the human population in the regions nearby such projects. Proceeding from the available data from expert examination reports the radiation exposure of the Bulgarian population in excess of the background as a result of mining and processing of uranium ores is analysed. The study covers about 135000 persons. The mean value of exposure above the background, attributable to the technologically increased background amounts to 3.04 mSv/a at effective background dose about 2.3 mSv/a. The collective effective dose is 410 mSv/a and represents about 5 per cent of the overall radiation exposure of the Bulgarian population

Radon exposure, cigarette smoking, and other mining experience in the beaverlodge uranium miners cohort

International Nuclear Information System (INIS)

L'Abbe, K.A.; Howe, G.R.; Burch, J.D.; Miller, A.B.; Abbatt, J.; Band, P.; Choi, W.; Du, J.; Feather, J.; Gallagher, R.

1991-01-01

A nested case-control study within the Beaverlodge Uranium Miners Cohort was undertaken to assess any possible contribution of confounding by smoking and other mining experience to the risk estimate derived from the original cohort study. Next of kin have been interviewed for 46 lung cancer cases and 95 controls enrolled in the Beaverlodge Uranium Miners Cohort Study who died between 1950 and 1980. Confounding by cigarette smoking and other mining experience appears unlikely to have contributed to the relative risk coefficient for exposure to Rn decay products derived in the parent study. Data for smoking and exposure to Rn decay products are consistent with a multiplicative model, although considerable caution must be applied to this interpretation

Health Effects of Chronic Arsenic Exposure

Directory of Open Access Journals (Sweden)

Young-Seoub Hong

2014-09-01

Full Text Available Arsenic is a unique element with distinct physical characteristics and toxicity whose importance in public health is well recognized. The toxicity of arsenic varies across its different forms. While the carcinogenicity of arsenic has been confirmed, the mechanisms behind the diseases occurring after acute or chronic exposure to arsenic are not well understood. Inorganic arsenic has been confirmed as a human carcinogen that can induce skin, lung, and bladder cancer. There are also reports of its significant association to liver, prostate, and bladder cancer. Recent studies have also suggested a relationship with diabetes, neurological effects, cardiac disorders, and reproductive organs, but further studies are required to confirm these associations. The majority of research to date has examined cancer incidence after a high exposure to high concentrations of arsenic. However, numerous studies have reported various health effects caused by chronic exposure to low concentrations of arsenic. An assessment of the health effects to arsenic exposure has never been performed in the South Korean population; thus, objective estimates of exposure levels are needed. Data should be collected on the biological exposure level for the total arsenic concentration, and individual arsenic concentration by species. In South Korea, we believe that biological exposure assessment should be the first step, followed by regular health effect assessments.

Chronic perfluorooctane sulfonate (PFOS) exposure induces hepatic steatosis in zebrafish

International Nuclear Information System (INIS)

Cheng, Jiangfei; Lv, Suping; Nie, Shangfei; Liu, Jing; Tong, Shoufang; Kang, Ning; Xiao, Yanyan; Dong, Qiaoxiang; Huang, Changjiang; Yang, Dongren

2016-01-01

Highlights: • PFOS chronic exposure induces sex-dependent hepatic steotosis in zebrafish. • PFOS interferes with β-oxidation, lipid synthesis, and lipid hepatic export process. • Zebrafish could be used as an alternative model for PFOS chronic toxicity screening. - Abstract: Perfluorooctane sulfonate (PFOS), one persistent organic pollutant, has been widely detected in the environment, wildlife and human. Currently few studies have documented the effects of chronic PFOS exposure on lipid metabolism, especially in aquatic organisms. The underlying mechanisms of hepatotoxicity induced by chronic PFOS exposure are still largely unknown. The present study defined the effects of chronic exposure to low level of PFOS on lipid metabolism using zebrafish as a model system. Our findings revealed a severe hepatic steatosis in the liver of males treated with 0.5 μM PFOS as evidenced by hepatosomatic index, histological assessment and liver lipid profiles. Quantitative PCR assay further indicated that PFOS significantly increase the transcriptional expression of nuclear receptors (nr1h3, rara, rxrgb, nr1l2) and the genes associated with fatty acid oxidation (acox1, acadm, cpt1a). In addition, chronic PFOS exposure significantly decreased liver ATP content and serum level of VLDL/LDL lipoprotein in males. Taken together, these findings suggest that chronic PFOS exposure induces hepatic steatosis in zebrafish via disturbing lipid biosynthesis, fatty acid β-oxidation and excretion of VLDL/LDL lipoprotein, and also demonstrate the validity of using zebrafish as an alternative model for PFOS chronic toxicity screening.

Chronic perfluorooctane sulfonate (PFOS) exposure induces hepatic steatosis in zebrafish

Energy Technology Data Exchange (ETDEWEB)

Cheng, Jiangfei; Lv, Suping; Nie, Shangfei; Liu, Jing; Tong, Shoufang; Kang, Ning; Xiao, Yanyan; Dong, Qiaoxiang [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China); Huang, Changjiang, E-mail: cjhuang5711@163.com [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China); Yang, Dongren, E-mail: yangdongren@yahoo.com [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China)

2016-07-15

Highlights: • PFOS chronic exposure induces sex-dependent hepatic steotosis in zebrafish. • PFOS interferes with β-oxidation, lipid synthesis, and lipid hepatic export process. • Zebrafish could be used as an alternative model for PFOS chronic toxicity screening. - Abstract: Perfluorooctane sulfonate (PFOS), one persistent organic pollutant, has been widely detected in the environment, wildlife and human. Currently few studies have documented the effects of chronic PFOS exposure on lipid metabolism, especially in aquatic organisms. The underlying mechanisms of hepatotoxicity induced by chronic PFOS exposure are still largely unknown. The present study defined the effects of chronic exposure to low level of PFOS on lipid metabolism using zebrafish as a model system. Our findings revealed a severe hepatic steatosis in the liver of males treated with 0.5 μM PFOS as evidenced by hepatosomatic index, histological assessment and liver lipid profiles. Quantitative PCR assay further indicated that PFOS significantly increase the transcriptional expression of nuclear receptors (nr1h3, rara, rxrgb, nr1l2) and the genes associated with fatty acid oxidation (acox1, acadm, cpt1a). In addition, chronic PFOS exposure significantly decreased liver ATP content and serum level of VLDL/LDL lipoprotein in males. Taken together, these findings suggest that chronic PFOS exposure induces hepatic steatosis in zebrafish via disturbing lipid biosynthesis, fatty acid β-oxidation and excretion of VLDL/LDL lipoprotein, and also demonstrate the validity of using zebrafish as an alternative model for PFOS chronic toxicity screening.

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

Carcinogenic effects of radon daughters, uranium ore dust and cigarette smoke in beagle dogs

International Nuclear Information System (INIS)

Cross, F.T.; Palmer, R.F.; Filipy, R.E.; Dagle, G.E.; Stuart, B.O.

1982-01-01

The development of pulmonary lesions in beagle dogs was studied following chronic inhalation exposures to radon (at 105 +- 20 nCi/l), radon daughters (at 605 +- 169 WL), uranium ore dust (at 12.9 +- 6.7 mg/m 3 ) and cigarette smoke. Chronic exposures to mixtures of these agents caused significant lifespan shortening compared with controls. Survival times of controls and smoke-exposed dogs were equivalent during the 4 to 5-yr mean survival time of the dogs exposed to radon-daughter and ore-dust mixtures (with or without added cigarette smoke). Animals with tumors of the respiratory tract generally has cumulative radon-daughter exposures exceeding 13,000 WLM; their survival time was longer than that of nontumor-bearing animals. Exposure to cigarette smoke had a mitigating effect on radon daughter-induced tumors. Exposures to smoke from 10 cigarettes/d, 7 d/wk produced no significant respiratory tract lesions. Exposure to 20 cigarettes/d, 7 d/wk resulted in pulmonary emphysema, fibrosis and chronic bronchitis and bronchiolitis. Emphysema and fibrosis were much more prevalent and severe in the dogs exposed to mixtures including radon daughters and uranium/ore dust. These dogs also had adenomatous lesions which progressed to squamous metaplasia of alveolar epithelium, epidermoid carcinoma and bronchioloalveolar carcinoma. Pathologic changes in the airways of these dogs were most prominent in the nasal mucosa, and included a few squamous carcinomas in the nasal cavity. (author)

HIGH LEVELS OF URANIUM IN GROUNDWATER OF ULAANBAATAR, MONGOLIA

Science.gov (United States)

Nriagu, Jerome; Nam, Dong-Ha; Ayanwola, Titilayo A.; Dinh, Hau; Erdenechimeg, Erdenebayar; Ochir, Chimedsuren; Bolormaa, Tsend-Ayush

2011-01-01

Water samples collected from 129 wells in seven of the nine sub-divisions of Ulaanbaatar were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) using Clean Lab methods. The levels of many trace elements were found to be very low with the average concentrations (ranges in brackets) being 0.9 (uranium were surprisingly elevated (mean, 4.6 μg/L; range uranium in drinking water. Local rocks and soils appear to be the natural source of the uranium. The levels of uranium in Ulaanbaatar's groundwater are in the range that has been associated with nephrotoxicity, high blood pressure, bone dysfunction and likely reproductive impairment in human populations. We consider the risk associated with drinking the groundwater with elevated levels of uranium in Ulaanbaatar to be a matter for some public health concern and conclude that the paucity of data on chronic effects of low level exposure is a risk factor for continuing the injury to many people in this city. PMID:22142646

Review of the toxicologic and radiologic risks to military personnel from exposure to depleted uranium during and after combat

National Research Council Canada - National Science Library

National Academies Press (U.S.); National Research Council (U.S.). Board on Environmental Studies and Toxicology; National Research Council (U.S.) Committee on Toxicologic and Radiologic Effects from Exposure to Depleted Uranium During and After Combat

2008-01-01

.... Depleted uranium is a toxic heavy metal and is weakly radioactive. Concerns have been raised about the adverse health effects from exposure to depleted uranium that is aerosolized during combat...

Effects of radionuclides (uranium et cesium 137) on the metabolism of vitamin D in rat

International Nuclear Information System (INIS)

Tissandie, Emilie

2007-01-01

Uranium and Cesium 137 ( 137 Cs) are both radionuclides found in the environment as a result of their accidental dispersion and/or natural presence. Consequently, some human populations are exposed to these radioelements mainly through chronic ingestion. Chemical and/or radiological toxicity of uranium and 13 7 Cs has been reported in kidney, liver and brain that play key-roles in vitamin D metabolism. Beside, alterations of both bone and phospho-calcium homeostasis have been reported after an acute or chronic contamination with uranium or 137 Cs. However, vitamin D, the major regulator of mineral homeostasis has never been studied up to now. The aim of this work was to investigate in vivo the effects of depleted (DU) or enriched uranium (EU) and of 137 Cs on vitamin D3 biosynthetic pathway in liver, kidney and brain. An experimental animal model was used for the first time to demonstrate that chronic exposure with environmental doses of 137 Cs and uranium could decrease the vitamin D active form level (1,25(OH)2D3) and lead to molecular modifications of cytochromes P450 (CYPs) enzymes involved in this metabolism and associated nuclear receptors. We demonstrated that both UA and UE contamination affected VDR (vitamin D receptor) and RXRa (retinoid X receptor alpha) expression, and consequently could modulate the expression of vitamin D target genes involved in calcium homeostasis in kidney. These results suggest that these effects could be due to the chemical toxicity of uranium. On the contrary, the main molecular targets of 137 Cs are CYPs involved in Vitamin D3 biosynthesis (CYP2R1, CYP27B1) in liver and brain. In this adult rat model such perturbations were not associated with a dys-regulation of mineral homeostasis. Conversely, chronic exposure with 137 Cs during postnatal development induce alterations of vitamin D metabolism associated with modifications of bone and phospho-calcium homeostasis, suggesting a greater susceptibility of the growing organism to

In vivo measurements of lead-210 for assessing cumulative radon exposure in uranium miners

Energy Technology Data Exchange (ETDEWEB)

Guilmette, R.A.; Laurer, G.R. [New York Univ. Inst. of Environmental Medicine, Tuxedo, NY (United States); Lambert, W.E.; Gilliland, F.D. [Univ. of New Mexico, Albuquerque, NM (United States)] [and others

1995-12-01

It has long been recognized that a major contributor to the uncertainty in risk analysis of lung cancer in uranium and other hard rock miners is the estimation of total radon progeny exposure of individual miners under study. These uncertainties arise from the fact that only a limited number of measurements of airborne {sup 222}Rn progeny concentrations were made in the mines during the times that the miners were being exposed, and that dosimeters capable of integrating the Rn progeny exposures of the miners did not exist. Historically, the cumulative exposures for individual uranium and other hard rock miners have been calculated by combining the employee`s work history, which may or may not have included time spent at different jobs within the mines and at different locations within the mines, with whatever periodic measurements of Rn and Rn progeny were available. The amount and quality of the measurement data varied enormously from mine to mine and from population to population. Because the quality of the exposure data collected during the period of active mining in the United STates cannot now be altered substantially, significant improvement in individual miner exposure estimates is only likely to be achieved if a new cumulative exposure metric is developed and implemented. The decay chain of Rn includes the production of {sup 210}Pb, which can accumulate in the skeleton in amounts proportional to the intake of Rn progeny. We hypothesize that the in vivo measurement of {sup 210}Pb in the skulls of miners will provide such a metric. In summary, the primary purpose of this pilot study to demonstrate the feasibility of measuring {sup 210}Pb in the heads of former uranium miners has been accomplished.

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

Chronic pesticide exposure and consequential keratectasia & corneal neovascularisation.

Science.gov (United States)

Sanyal, Shalini; Law, Atrayo; Law, Sujata

2017-11-01

Ocular toxicity as a consequence of chronic pesticide exposure is one of the health hazards caused due to extended exposure to pesticides. The cornea, due to its position as the outer ocular layer and its role in protecting the internal layers of the eye; is gravely affected by this xenobiotic insult to the eye, leading to ocular irritation and damage to normal vision. The deleterious effects of chronic pesticide exposure on the various corneal layers and the ocular risks involved therein, were explored by mimicking the on-field scenario. Cytological, histological and flowcytometric parameters were taken into consideration to determine the enhanced risk of corneal neovascularisation and keratectasia, specifically, keratoconus. Chronic exposure to pesticides leads to heightened ocular morbidity wherein there were visible pathophysiological changes to the ocular surface. The cornea was found to be adversely affected with visible protuberance in a cone-like shape, characteristic of keratoconus in a majority of the experimental animals. Further analyses revealed a detrimental impact on all the corneal layers and an amplified expression of inflammation markers such as TNF-α, VCAM-1 and ICAM-1. Additionally, it was found that post pesticide exposure, the corneal surface developed hypoxia, leading to a significant increase of angiogenesis promoting factors and consequential neovascularisation. Apart from ocular toxicity, chronic exposure to pesticides significantly increases the risks of keratectasia and corneal neovascularisation; disorders which lead to diminished vision and if untreated, blindness. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Inhalation hazards to uranium miners

International Nuclear Information System (INIS)

Cross, F.T.

1986-01-01

This project is investigating levels of uranium mine air contaminants, using both large and small experimental animals to model human respiratory system diseases. Lung cancer and deaths by degenerative lung disease have reached epidemic proportions among uranium miners, but the cause-effect relationships for these diseases are based on inadequate epidemiological data. This project identifies uranium mine air 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. Histopathologic data from serially sacrificed rats are reported for approximately 20- to 640- working-level-month (WLM) radon-daughter exposures delivered at one-tenth the rate of previous exposures. Exposure of male rats to radon daughters and uranium ore dust continues, along with exposure of male and female beagle dogs to uranium ore dust alone

Individual monitoring of internal exposure to uranium oxides in two fuel fabrication plants

International Nuclear Information System (INIS)

Bourdeix, F.; Achiary, J.; Berard, P.

1989-01-01

Individual monitoring of personal exposure to inhalation of uranium oxides throughout the manufacture of fuel for pressurized water reactor (PWR) includes lung gamma-spectrometry, fecal analysis and urine analysis. Examination of the results shows the following: internal exposure is the consequence of repeated intake incidents as revealed by early peaks of urinary and particularly fecal elimination; a shift is often observed with the results of aerosol concentration measured through air collectors; the measured variations of uranium lung incorporations are relatively fast (apparent mean period 165 d). Correct evaluation of the effective dose equivalent from inhalation requires further information concerning the aerosol size distribution at work stations, the physico-chemical characteristics of the product leading to an estimate of its actual biological solubility, and the measurement of the fraction of aerosol liable to intake with an individual portable collector [fr

210Pb in bone in vivo - a biodosimeter for assessing uranium miner radon progeny exposure

International Nuclear Information System (INIS)

Guilmette, R.A.; Snipes, M.B.; Hoover, M.D.; Leggett, R.W.; Laurer, G.R.; Lambert, W.E.; Coons, T.A.; Gilliland, F.D.

2002-01-01

A joint analysis of the results of 11 epidemiological studies of lung cancer among uranium miners has shown a significant level of variability in the relative risk per unit of exposure - in the range of a factor of 30 (Lubin et al., 1994). A significant fraction of the uncertainty associated with these risk coefficients may be due to differences in the methods and quality of data used in calculating cumulative exposures, in WLM, for the various miner populations. We hypothesize that in vivo measurement of 210 Pb, a long-lived radon decay product that is retained in bone, will provide an improved measure of Rn progeny exposures received by individual miners during their mining careers. To accomplish such in vivo measurements, the lovelace in vivo bioassay facility (LIVBF) was modified to obtain an optimized counting geometry for measuring 210 Pb in the skull. Six 12.7 cm diameter phoswich detectors were positioned about the head of a reclining subject (one in the posterior, and one in the anterior position, and four about the mid-sagittal plane), and photon emission from the skull was measured using anticoincidence multichannel analysis electronics. We analyzed the in vivo data from about 90 former uranium miners from the grants mining district, and compared the recorded WLM exposures for each uranium miner (data from the UNM epidemiological data base) with a WLM exposure calculated using a model developed specifically for this study. This model couples a Pb biokinetic model with the ICRP publication 66 respiratory tract dosimetry model. The analyses show that the independent measurements of exposure are statistically correlated, but with a large degree of variability occurring among individual values, and that a major source of uncertainty in mining exposure estimation is the uncertainty involved in accounting for non-mining sources of 210 Pb. (orig.)

Effects of long-term chronic exposure to radionuclides in plant populations

International Nuclear Information System (INIS)

Geras'kin, S.; Evseeva, T.; Oudalova, A.

2013-01-01

The results of field studies carried out on different plant species (winter rye and wheat, spring barley, oats, Scots pine, wild vetch, crested hairgrass) in various radioecological situations (nuclear weapon testing, the Chernobyl accident, uranium and radium processing) to investigate the effects of long-term chronic exposure to radionuclides are discussed. Plant populations growing in areas with relatively low levels of pollution are characterized by an increased level of both cytogenetic disturbances and genetic diversity. Although ionizing radiation causes primary damage at the molecular level, there are emergent effects at the level of populations, non-predictable from the knowledge of elementary mechanisms of cellular effects formation. Accumulation of cellular alterations may afterward influence biological parameters important for populations such as health and reproduction. Presented data provide evidence that in plant populations inhabiting heavily contaminated territories cytogenetic damage could be accompanied by a decrease in reproductive capacity. However, in less contaminated sites, because of the scarcity of data available, a steady relationship between cytogenetic effects and reproductive capacity was not revealed. Under radioactive contamination of the plant's environment, a population's resistance to exposure may increase. However, there are radioecological situations where an enhanced radioresistance has not evolved or has not persisted

Leukemia, lymphoma and multiple myeloma mortality (1950–1999) and incidence (1969–1999) in the Eldorado uranium workers cohort

Energy Technology Data Exchange (ETDEWEB)

Zablotska, Lydia B., E-mail: Lydia.Zablotska@ucsf.edu [Department of Epidemiology and Biostatistics, School of Medicine, University of California, San Francisco, CA 94118 (United States); Lane, Rachel S.D. [Radiation and Health Sciences Division, Directorate of Environmental and Radiation Protection and Assessment, Canadian Nuclear Safety Commission, Ottawa, ON, Canada K1P 5S9 (Canada); Frost, Stanley E. [Frost and Frost Consultants, Saskatoon, SK, Canada S7H 0A1 (Canada); Thompson, Patsy A. [Radiation and Health Sciences Division, Directorate of Environmental and Radiation Protection and Assessment, Canadian Nuclear Safety Commission, Ottawa, ON, Canada K1P 5S9 (Canada)

2014-04-01

Uranium workers are chronically exposed to low levels of radon decay products (RDP) and gamma (γ) radiation. Risks of leukemia from acute and high doses of γ-radiation are well-characterized, but risks from lower doses and dose-rates and from RDP exposures are controversial. Few studies have evaluated risks of other hematologic cancers in uranium workers. The purpose of this study was to analyze radiation-related risks of hematologic cancers in the cohort of Eldorado uranium miners and processors first employed in 1932–1980 in relation to cumulative RDP exposures and γ-ray doses. The average cumulative RDP exposure was 100.2 working level months and the average cumulative whole-body γ-radiation dose was 52.2 millisievert. We identified 101 deaths and 160 cases of hematologic cancers in the cohort. Overall, male workers had lower mortality and cancer incidence rates for all outcomes compared with the general Canadian male population, a likely healthy worker effect. No statistically significant association between RDP exposure or γ-ray doses, or a combination of both, and mortality or incidence of any hematologic cancer was found. We observed consistent but non-statistically significant increases in risks of chronic lymphocytic leukemia (CLL) and Hodgkin lymphoma (HL) incidence and non-Hodgkin lymphoma (NHL) mortality with increasing γ-ray doses. These findings are consistent with recent studies of increased risks of CLL and NHL incidence after γ-radiation exposure. Further research is necessary to understand risks of other hematologic cancers from low-dose exposures to γ-radiation. - Highlights: • We analyzed long-term follow-up for hematologic cancers of the Eldorado uranium workers. • Workers were exposed to a unique combination of radon decay products (RDP) and gamma (γ) ray doses. • Exposures to RDP and γ-ray doses were not associated with significantly increased risks of cancers. • Radiation risks of chronic lymphocytic leukemia (CLL) and

Biological characterization of radiation exposure and dose estimates for inhaled uranium milling effluents. Annual progress report April 1, 1982-March 31, 1983

International Nuclear Information System (INIS)

Eidson, A.F.

1984-05-01

The problems addressed are the protection of uranium mill workers from occupational exposure to uranium through routine bioassay programs and the assessment of accidental worker exposures. Comparisons of chemical properties and the biological behavior of refined uranium ore (yellowcake) are made to identify important properties that influence uranium distribution patterns among organs. These studies will facilitate calculations of organ doses for specific exposures and associated health risk estimates and will identify important bioassay procedures to improve evaluations of human exposures. A quantitative analytical method for yellowcake was developed based on the infrared absorption of ammonium diuranate and U 3 O 8 mixtures in KBr. The method was applied to yellowcake samples obtained from six operating mills. The composition of yellowcake from the six mills ranged from nearly pure ammonium diuranate to nearly pure U 3 O 8 . The composition of yellowcake samples taken from lots from the same mill was only somewhat less variable. Because uranium mill workers might be exposed to yellowcake either by contamination of a wound or by inhalation, a study of retention and translocation of uranium after subcutaneous implantation in rats was done. The results showed that 49% of the implanted yellowcake cleared from the body with a half-time (T sub 1/2) in the body of 0.3 days, and the remainder was cleared with a T sub 1/2 of 11 to 30 days. Exposures of Beagle dogs by nose-only inhalation to aerosols of commercial yellowcake were completed. Biochemical indicators of kidney dysfunction that appeared in blood and urine 4 to 8 days after exposure to the more soluble yellowcake showed significant changes in dogs, but levels returned to normal by 16 days after exposure. No biochemical evidence of kidney dysfunction was observed in dogs exposed to the less soluble yellowcake form. 18 figures, 9 tables

Uranium bone content as an indicator of chronic environmental exposure from drinking water.

Science.gov (United States)

Larivière, Dominic; Tolmachev, Sergei Y; Kochermin, Vera; Johnson, Sonia

2013-07-01

Uranium (U) is an ubiquitous radioelement found in drinking water and food. As a consequence of its prevalence, most humans ingest a few micrograms (μg) of this element daily. It is incorporated in various organs and tissues. Several studies have demonstrated that ingested U is deposited mainly in bones. Therefore, U skeletal content could be considered as a prime indicator for low-level chronic intake. In this study, 71 archived vertebrae bone samples collected in seven Canadian cities were subjected to digestion and U analysis by inductively coupled plasma mass spectrometry. These results were correlated with U concentrations in municipal drinking water supplies, with the data originating from historical studies performed by Health Canada. A strong relationship (r(2) = 0.97) was observed between the averaged U total skeletal content and averaged drinking water concentration, supporting the hypothesis that bones are indeed a good indicator of U intake. Using a PowerBASIC compiler to process an ICRP systemic model for U (ICRP, 1995a), U total skeletal content was estimated using two gastrointestinal tract absorption factors (ƒ1 = 0.009 and 0.03). Comparisons between observed and modelled skeletal contents as a function of U intake from drinking water tend to demonstrate that neither of the ƒ1 values can adequately estimate observed values. An ƒ1value of 0.009 provides a realistic estimate for intake resulting from food consumption only (6.72 μg) compared to experimental data (7.4 ± 0.8 μg), whereas an ƒ1value of 0.03 tends to better estimate U skeletal content at higher levels of U (1-10 μg L(-1)) in drinking water. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mortality patterns among a retrospective cohort of uranium mill workers

International Nuclear Information System (INIS)

Waxweiler, R.J.; Archer, V.E.; Roscoe, R.J.; Watanabe, A.; Thun, M.J.

1983-01-01

The long-term health effects associated with the milling of uranium ore are of interest particularly because of exposures to uranium and thorium-230. Excess risks of pulmonary and lymphatic malignancies have been suggested by previous epdiemiologic studies of persons milling or smelting uranium ores, and nephrotoxic effects of uranium have been reported in both man and animals. To test these three previously reported associations and to assess all cause-specific mortality patterns among uranium mill workers, we carried out a retrospective cohort study of 2002 uranium millers employed in any of seven mills at least one year before 1972. Ninety-eight percent (98%) followup of the cohort through 1977 resulted in 533 deaths observed versus 605 expected from US White male mortality rates. Mortality from most causes was lower than expected. Significant excess risks were found only for nonmalignant respiratory disease and miscellaneous accidents but not for any of the three diseases of a priori interest. However, nonsignificant excesses were found for lymphatic malignancies after 20 years latency and for death due to chronic nephritis among short-term workers

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

Determination of internal exposure doses of the personnel of uranium-mining company due to radon isotopes decay products

International Nuclear Information System (INIS)

Sevostyanov, V.N.

2004-01-01

This work carries out a determination of individual doses of internal exposure of the staff of the uranium-mining company in Kazakhstan due to radon decay products. The company extracts uranium by in-situ leaching. After leaching, uranium is sorbed from a solution in facilities where the staff is located. The state of three uranium mines was analyzed. The dose determination was conducted in tune with the proposed method by using integral alpha-tracking detectors to identify the content of 222 Rn and express appliances to identify the content of radio-active aerosols in air of the working area for determination the equilibrium coefficient. The measurements were performed within one year. The work produced the results in average annual values of radon and thoron decay products activity concentration and variation, equilibrium coefficient variation, and so-called expressive-to-integral value conversion factor. The obtained personnel's individual radiation doses due to radon exposure for this period lie within the range of < 1 mSv/year. (author)

The oxidative corrosion of carbide inclusions at the surface of uranium metal during exposure to water vapour

International Nuclear Information System (INIS)

Scott, T.B.; Petherbridge, J.R.; Harker, N.J.; Ball, R.J.; Heard, P.J.; Glascott, J.; Allen, G.C.

2011-01-01

Highlights: → High resolution imagery (FIB, SEM and SIMS) of carbide inclusions in uranium metal. → Real time images following the reaction of the carbide inclusions with water vapour. → Shown preferential consumption of carbide over that of the bulk metal. → Quantity of impurities in the metal therefore seriously influence reaction rate. → Metal purity must be considered when storing uranium in air or moist conditions. - Abstract: The reaction between uranium and water vapour has been well investigated, however discrepancies exist between the described kinetic laws, pressure dependence of the reaction rate constant and activation energies. Here this problem is looked at by examining the influence of impurities in the form of carbide inclusions on the reaction. Samples of uranium containing 600 ppm carbon were analysed during and after exposure to water vapour at 19 mbar pressure, in an environmental scanning electron microscope (ESEM) system. After water exposure, samples were analysed using secondary ion mass spectrometry (SIMS), focused ion beam (FIB) imaging and sectioning and transmission electron microscopy (TEM) with X-ray diffraction (micro-XRD). The results of the current study indicate that carbide particles on the surface of uranium readily react with water vapour to form voluminous UO 3 .xH 2 O growths at rates significantly faster than that of the metal. The observation may also have implications for previous experimental studies of uranium-water interactions, where the presence of differing levels of undetected carbide may partly account for the discrepancies observed between datasets.

Inhalation hazards to uranium miners

International Nuclear Information System (INIS)

Cross, F.T.

1985-01-01

This project is investigating levels of uranium mine air contaminants, using both large and small experimental animals to model human respiratory system disease. Lung cancer and deaths by degenerative lung disease have reached epidemic proportions 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. Histopathologic data from rats are shown for approximately 300- to 10,000-working-level-month (WLM) radon-daughter exposures. Exposure of male rats to radon daughters and uranium ore dust continues, along with exposure of male and female beagle dogs to uranium ore dust alone. 4 tables

Radon exposure and mortality among the French cohort of uranium miners: 1946-1999

International Nuclear Information System (INIS)

Vacquier, B.; Tirmarche, M.; Laurier, D.; Caer, S.; Quesne, B.

2006-01-01

Full text of publication follows: The French cohort of uranium miners aims at evaluating the mortality risk of miners exposed to low levels of radon and its decay products and to other occupational hazards. Its primary aim is the quantification of the relationship between cumulated radon exposure and the risk of lung cancer death. However this study also allows to analyse risks for causes of death other than lung cancer. We present a new analysis of the mortality based on an extended follow-up of the cohort to end of 1999. Materials and methods: The French cohort of uranium miners has been followed by the Institut de Radioprotection et de Surete Nucleaire (I.R.S.N.) since the 1980's, in collaboration with the Occupational Medical Service of Compagnie Generale des Matieres Nucleaires (Cogema). The cohort was recently enlarged and the follow-up extended up to 1999. It includes men employed as miners for at least 1 year since 1946 at the Commissariat a l Energie Atomique (Cea) or at the Cogema. Individual vital status was ascertained through a national database and causes of death were determined according to death certificates. For each miner, yearly radon exposures was reconstructed and expressed in working level month (W.L.M.). Risk of death was estimated relatively to external reference rates from the general French male population. The classical method of standardized mortality ratios (S.M.R.s) was used to adjust for age and calendar year. Exposure-risk relationships have been estimated by Poisson regression, using a linear excess relative risk (E.R.R.) model with a lag time of 5 years. Results: The cohort comprises 5,098 miners. The mean duration of follow -up is 30.1 years (total of 153,272 person-years). The number of radon exposed miners is 4,134 with an average cumulative radon exposure of 36.5 W.L.M.. Miners lost to follow-up represent 1.4% of the cohort. A total of 1,471 deaths before age 85 is observed up to 1999. The analysis shows no excess for all

Impact of chronic and acute pesticide exposures on periphyton communities

Energy Technology Data Exchange (ETDEWEB)

Tlili, Ahmed, E-mail: ahmed.tlili@cemagref.fr [CEMAGREF, UR MAEP, 3 quai Chauveau CP 69336 Lyon Cedex 09 (France); Montuelle, Bernard, E-mail: bernard.montuelle@cemagref.fr [CEMAGREF, UR MAEP, 3 quai Chauveau CP 69336 Lyon Cedex 09 (France); INRA UMR CARRTEL, Laboratoire de Microbiologie Aquatique, BP 511, 74203, Thonon Cedex (France); Berard, Annette, E-mail: annette.berard@avignon.inra.fr [INRA UMR EMMAH 1114, Domaine Saint-Paul-Site Agroparc 84914 Avignon Cedex 9 (France); Bouchez, Agnes, E-mail: agnes.bouchez@thonon.inra.fr [INRA UMR CARRTEL, Laboratoire de Microbiologie Aquatique, BP 511, 74203, Thonon Cedex (France)

2011-05-01

Aquatic ecosystems face variable exposure to pesticides, especially during floodings which are associated with short bursts of high contaminant concentrations that influence biological systems. A study was undertaken to highlight the impact of the herbicide diuron applied in mixture with the fungicide tebuconazole on natural periphyton during flooding events. Periphyton were grown in two series of two lotic outdoor mesocosms: one series was non-contaminated while the other was exposed to chronic contamination. After 4 weeks, one channel of each series was exposed to three successive pulses, with each pulse followed by one week of recovery. Impacts on periphyton were assessed by using Denaturing Gel Gradient Electrophoresis to characterize eukaryotic community structure. At a functional scale, photosynthetic efficiency was quantified during each pulse, and the induced tolerance to diuron was estimated by performing short-term inhibition tests based on photosynthetic efficiency. Moreover, pesticide concentrations in the water column and periphyton matrix were measured. Diuron was adsorbed in the periphyton during each pulse and desorbed 13 h after pulse end. The different pulses affected the eukaryotic community structures of the control biofilms, but not of the chronically exposed ones. During the first pulse, photosynthetic efficiency was correlated with pesticide concentration in the water phase, and there was no difference between periphyton from chronically contaminated channels and control channels. However, during the second and third pulses, the photosynthetic efficiency of periphyton chronically exposed to pesticides appeared to be less impacted by the acute pulsed exposure of pesticide. These changes were consistent with the acquisition of induced tolerance to diuron since only after the third pulse that periphyton from chronic channel became tolerant to diuron. Our experimental study indicates that the effects of pulsed acute exposures to pesticides on

Impact of chronic and acute pesticide exposures on periphyton communities

International Nuclear Information System (INIS)

Tlili, Ahmed; Montuelle, Bernard; Berard, Annette; Bouchez, Agnes

2011-01-01

Aquatic ecosystems face variable exposure to pesticides, especially during floodings which are associated with short bursts of high contaminant concentrations that influence biological systems. A study was undertaken to highlight the impact of the herbicide diuron applied in mixture with the fungicide tebuconazole on natural periphyton during flooding events. Periphyton were grown in two series of two lotic outdoor mesocosms: one series was non-contaminated while the other was exposed to chronic contamination. After 4 weeks, one channel of each series was exposed to three successive pulses, with each pulse followed by one week of recovery. Impacts on periphyton were assessed by using Denaturing Gel Gradient Electrophoresis to characterize eukaryotic community structure. At a functional scale, photosynthetic efficiency was quantified during each pulse, and the induced tolerance to diuron was estimated by performing short-term inhibition tests based on photosynthetic efficiency. Moreover, pesticide concentrations in the water column and periphyton matrix were measured. Diuron was adsorbed in the periphyton during each pulse and desorbed 13 h after pulse end. The different pulses affected the eukaryotic community structures of the control biofilms, but not of the chronically exposed ones. During the first pulse, photosynthetic efficiency was correlated with pesticide concentration in the water phase, and there was no difference between periphyton from chronically contaminated channels and control channels. However, during the second and third pulses, the photosynthetic efficiency of periphyton chronically exposed to pesticides appeared to be less impacted by the acute pulsed exposure of pesticide. These changes were consistent with the acquisition of induced tolerance to diuron since only after the third pulse that periphyton from chronic channel became tolerant to diuron. Our experimental study indicates that the effects of pulsed acute exposures to pesticides on

Improving the Assessment of Internal Occupational Exposure to Natural Uranium from Urinalysis by Normalization to Creatinine

International Nuclear Information System (INIS)

Marko, R.; Kol, R.; Katorza, E.; German, U.; Balaish, Y.; Lorber, A.; Karpas, Z.

2002-01-01

The assessment of occupational internal exposure to natural uranium is normally carried out by combining Uranium Lung Detection (ULD) and urine analysis. The ULD is a direct measurement of the uranium content in lungs. The urine analysis measures the amount of uranium excreted from the body. The biokinetic models that are in use for dose assessments from urine analysis measurements are usually based on 24-hour urine collection. There are three traditional methods to collect urine samples: a) 24-hour collection - the subject is asked to collect all the urine excreted during a 24-hour period. b) Simulated 24-hour collection - the subject collects all the urine excreted during three consecutive 8-hour workdays. c) Spot samples - the subject gives a single urine sample at some time during work hours

The oxidative corrosion of carbide inclusions at the surface of uranium metal during exposure to water vapour.

Science.gov (United States)

Scott, T B; Petherbridge, J R; Harker, N J; Ball, R J; Heard, P J; Glascott, J; Allen, G C

2011-11-15

The reaction between uranium and water vapour has been well investigated, however discrepancies exist between the described kinetic laws, pressure dependence of the reaction rate constant and activation energies. Here this problem is looked at by examining the influence of impurities in the form of carbide inclusions on the reaction. Samples of uranium containing 600 ppm carbon were analysed during and after exposure to water vapour at 19 mbar pressure, in an environmental scanning electron microscope (ESEM) system. After water exposure, samples were analysed using secondary ion mass spectrometry (SIMS), focused ion beam (FIB) imaging and sectioning and transmission electron microscopy (TEM) with X-ray diffraction (micro-XRD). The results of the current study indicate that carbide particles on the surface of uranium readily react with water vapour to form voluminous UO(3) · xH(2)O growths at rates significantly faster than that of the metal. The observation may also have implications for previous experimental studies of uranium-water interactions, where the presence of differing levels of undetected carbide may partly account for the discrepancies observed between datasets. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Consideration of measurement errors in the analysis of the risk related to the exposure to ionising radiation in an occupational cohort: application to the French cohort of uranium miners

International Nuclear Information System (INIS)

Allodji, Rodrigue Setcheou

2011-01-01

In epidemiological studies, measurement errors in exposure can substantially bias the estimation of the risk associated to exposure. A broad variety of methods for measurement error correction has been developed, but they have been rarely applied in practice, probably because their ability to correct measurement error effects and their implementation are poorly understood. Another important reason is that many of the proposed correction methods require to know measurement errors characteristics (size, nature, structure and distribution). The aim of this thesis is to take into account measurement error in the analysis of risk of lung cancer death associated to radon exposure based on the French cohort of uranium miners. The mains stages were (1) to assess the characteristics (size, nature, structure and distribution) of measurement error in the French uranium miners cohort, (2) to investigate the impact of measurement error in radon exposure on the estimated excess relative risk (ERR) of lung cancer death associated to radon exposure, and (3) to compare the performance of methods for correction of these measurement error effects. The French cohort of uranium miners includes more than 5000 miners chronically exposed to radon with a follow-up duration of 30 years. Measurement errors have been characterized taking into account the evolution of uranium extraction methods and of radiation protection measures over time. A simulation study based on the French cohort of uranium miners has been carried out to investigate the effects of these measurement errors on the estimated ERR and to assess the performance of different methods for correcting these effects. Measurement error associated to radon exposure decreased over time, from more than 45% in the early 70's to about 10% in the late 80's. Its nature also changed over time from mostly Berkson to classical type from 1983. Simulation results showed that measurement error leads to an attenuation of the ERR towards the null

Comparison of late effects of single x-ray exposure, chronic tritiated water ingestion, and chronic cesium-137 gamma exposure in mice

International Nuclear Information System (INIS)

Carsten, A.L.; Cronkite, E.P.

1979-01-01

There is concern over the possible late effects resulting from chronic exposure to tritiated water, a primary by-product of power reactors. We are comparing the genetic and somatic effects of tritiated water ingestion to acute x-ray or chronic cesium-137 gamma-ray exposures. Eight week old mice were maintaned on tritiated water in concentrations of 0.3, 1.0, and 3.0 μCi/ml. Identical animals received cesium-137 gamma exposures equivalent to that from the tritiated water. At 4 week intervals, animals were sacrificed and the hematopoietic stem cell content and cellularity of the bone marrow determined. For comparison of acute and chronic effects, one group of mice received a single whole-body x-ray exposure of 525 rads. The x-irradiated animals showed an immediate sharp decrease in marrow cellularity followed by gradual return to normal levels, with a lifelong reduction in number of marrow stem cells. Animals exposed to the two higher concentrations of tritiated water showed only slight reductions in marrow cellularity, with a lifelong reduction in hematopoietic stem cells in the bone marrow. Comparison of the external gamma exposures to chronic tritiated water ingestion indicates similar patterns. Maintenance of normal cellularity with a reduced number of stem cells in x-rayed animals was shown by tritiated thymidine cytocide to be due to the reduction in number of stem cells in the resting G/sub O/ stage. At this time it is not possible to determine whether there is a significant difference in relative biological effectiveness of tritiated water compared to cesium-137 gamma rays; however, indications are that they are similar

Generally applicable limits on intakes of uranium based on its chemical toxicity and the radiological significance of intakes at those limits

International Nuclear Information System (INIS)

Thorne, M C; Wilson, J

2015-01-01

Uranium is chemically toxic and radioactive, and both considerations have to be taken into account when limiting intakes of the element, in the context of both occupational and public exposures. Herein, the most recent information available on the chemical toxicity and biokinetics of uranium is used to propose new standards for limiting intakes of the element. The approach adopted allows coherent standards to be set for ingestion and inhalation of different chemical forms of the element by various age groups. It also allows coherent standards to be set for occupational and public exposures (including exposures of different age groups) and for various exposure regimes (including short-term and chronic exposures). The proposed standards are more restrictive than those used previously, but are less restrictive than the Minimal Risk Levels proposed recently by the US Agency for Toxic Substances and Disease Registry. Having developed a set of proposed limits based solely on chemical toxicity considerations, the radiological implications of exposure at those proposed limits are investigated for natural, depleted and enriched uranium. (paper)

Residential proximity to abandoned uranium mines and serum inflammatory potential in chronically exposed Navajo communities.

Science.gov (United States)

Harmon, Molly E; Lewis, Johnnye; Miller, Curtis; Hoover, Joseph; Ali, Abdul-Mehdi S; Shuey, Chris; Cajero, Miranda; Lucas, Selita; Zychowski, Katherine; Pacheco, Bernadette; Erdei, Esther; Ramone, Sandy; Nez, Teddy; Gonzales, Melissa; Campen, Matthew J

2017-07-01

Members of the Navajo Nation, who possess a high prevalence of cardiometabolic disease, reside near hundreds of local abandoned uranium mines (AUM), which contribute uranium, arsenic and other metals to the soil, water and air. We recently reported that hypertension is associated with mine waste exposures in this population. Inflammation is a major player in the development of numerous vascular ailments. Our previous work establishing that specific transcriptional responses of cultured endothelial cells treated with human serum can reveal relative circulating inflammatory potential in a manner responsive to pollutant exposures, providing a model to assess responses associated with exposure to these waste materials in this population. To investigate a potential link between exposures to AUM and serum inflammatory potential in affected communities, primary human coronary artery endothelial cells were treated for 4 h with serum provided by Navajo study participants (n=145). Endothelial transcriptional responses of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and chemokine ligand 2 (CCL2) were measured. These transcriptional responses were then linked to AUM exposure metrics, including surface area-weighted AUM proximity and estimated oral intake of metals. AUM proximity strongly predicted endothelial transcriptional responses to serum including CCL2, VCAM-1 and ICAM-1 (Puranium did not, even after controlling for all major effect modifiers. Inflammatory potential associated with proximity to AUMs, but not oral intake of specific metals, additionally suggests a role for inhalation exposure as a contributor to cardiovascular disease.

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/

The toxicology of uranium compounds

International Nuclear Information System (INIS)

Brickner, D.

1988-11-01

This review of literature presents and criticises the current knowledge relevant to risk assessment in cases of human exposure to natural uranium compounds due to industrial accidents. The major risk of high uranium exposure is renal-tubular damage which may lead to acute renal insufficiency and death. Radiation damage is not expected in these circumstances. In this review the metabolism of uranium in the body, the health effects and the possible medical treatment are discussed, with an emphasis on relatively large exposure of short duration. The current ICRP lung model does not represent all the factors affecting the kinetics of uranium oxides in the respiratory tract. The significance of these factors, not represented by the model, for risk assessment in such exposures, is not known. The current recommendations for treatment are not scientifically based. Further investigations are urgently needed to enable a rational medical preparadness

Acute and chronic toxicity of effluent water from an abandoned uranium mine.

Science.gov (United States)

Antunes, S C; Pereira, R; Gonçalves, F

2007-08-01

Inactive or abandoned mines represent a significant source of environmental, chemical, physical, and aesthetic impact. Among concerning situations, the occurrence of abandoned or semi-abandoned mine-associated ponds (for sedimentation of solids, for effluent neutralization, or for washing the ore) is a common feature in this type of system. These ponds are a source of contamination for the groundwater resources and adjacent soils, because they lack appropriate impermeabilization. The use of this water for agriculture may also pose chronic risks to humans. In Portugal, these problems have been diagnosed and some remediation projects have been developed. The purpose of our study was to evaluate the acute and chronic toxicity of water samples collected from the aquatic system surrounding an abandoned uranium mine (Cunha Baixa, Mangualde, Central Portugal). The present study focuses on the water compartment, whose toxicity was evaluated by means of standard toxicity assays using two Daphnia species (D. longispina and D. magna). Three different ponds were used in the characterization of the aquatic system from Cunha Baixa mine: a reference pond (Ref), a mine effluent treatment pond (T), and a mine pit pond (M). Metal analyses performed in the water samples from these ponds showed values that, in some cases, were much higher than maximum recommendable values established (especially Al, Mn) by Portuguese legislation for waters for crop irrigation. Acute toxicity was only observed in the mine pit pond, with EC(50) values of 28.4% and 50.4% for D. longispina and D. magna, respectively. The significant impairment of chronic endpoints, translated in reductions in the population growth rate for both species, gives rise to concerns regarding the potential risks for aquatic zooplanktonic communities, from local receiving waters, potentially exposed to point source discharges of the treated and nontreated effluent from Cunha Baixa uranium mine.

Comparison of radon-daughter exposures calculated for US- underground uranium miners based on MSHA and company records

International Nuclear Information System (INIS)

Cooper, W.E.

1981-01-01

How accurate are past and present employee radon-daughter exposure records of underground uranium miners employed in the United States. This often-debated question is essential for future substantiation of safe exposure limits. An apparent discrepancy between company-reported exposures and Mining Enforcement and Safety Administration (MESA) projected exposures was detected in 1977. For these reasons a need for an updated comparison of these exposure data was indicated. This paper gives some of the conclusions of the earlier study and compares more recent exposure records compiled by the Atomic Industrial Forum, Inc., with projected exposures based on sampling by Federal mine inspectors

Long-term ecological effects of exposure to uranium

International Nuclear Information System (INIS)

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

1976-03-01

The consequences of releasing natural and depleted uranium to terrestrial ecosystems during development and testing of depleted uranium munitions were investigated. At Eglin Air Force Base, Florida, soil at various distances from armor plate target butts struck by depleted uranium penetrators was sampled. The upper 5 cm of soil at the target bases contained an average of 800 ppM of depleted uranium, about 30 times as much as soil at 5- to 10-cm depth, indicating some vertical movement of depleted uranium. Samples collected beyond about 20 m from the targets showed near-background natural uranium levels, about 1.3 +- 0.3 μg/g or ppM. Two explosives-testing areas at the Los Alamos Scientific Laboratory (LASL) were selected because of their use history. E-F Site soil averaged 2400 ppM of uranium in the upper 5 cm and 1600 ppM at 5-10 cm. Lower Slobovia Site soil from two subplots averaged about 2.5 and 0.6 percent of the E-F Site concentrations. Important uranium concentration differences with depth and distance from detonation points were ascribed to the different explosive tests conducted in each area. E-F Site vegetation samples contained about 320 ppM of uranium in November 1974 and about 125 ppM in June 1975. Small mammals trapped in the study areas in November contained a maximum of 210 ppM of uranium in the gastrointestinal tract contents, 24 ppM in the pelt, and 4 ppM in the remaining carcass. In June, maximum concentrations were 110, 50, and 2 ppM in similar samples and 6 ppM in lungs. These data emphasized the importance of resuspension of respirable particles in the upper few millimeters of soil as a contamination mechanism for several components of the LASL ecosystem

Uranium: biokinetics and toxicity; Biocinetique et toxicite de l'uranium

Energy Technology Data Exchange (ETDEWEB)

Menetrier, F.; Renaud-Salis, V.; Flury-Herard, A

2000-07-01

This report was achieved as a part of a collaboration with the Fuel Cycle Direction. Its aim was to give the state of the art about: the behaviour of uranium in the human organism (biokinetics) after ingestion, its toxicity (mainly renal) and the current regulation about its incorporation. Both in the upstream and in the downstream of the fuel cycle, uranium remains, quantitatively, the first element in the cycle which is, at the present time, temporarily disposed or recycled. Such a considerable quantity of uranium sets the problem of its risk on the health. In the long term, the biosphere may be affected and consequently the public may ingest water or food contaminated with uranium. In this way, radiological and chemical toxicity risk may be activated. This report emphasizes: the necessity of confirming some experimental and epidemiological biokinetic data used or not in the ICRP models. Unsolved questions remain about the gastrointestinal absorption according to chemical form (valency state, mixtures...), mass and individual variations (age, disease) further a chronic ingestion of uranium. It is well established that uranium is mainly deposited in the skeleton and the kidney. But the skeleton kinetics following a chronic ingestion and especially in some diseases has to be more elucidated; the necessity of taking into account uranium at first as a chemical toxic, essentially in the kidney and determining the threshold of functional lesion. In this way, it is important to look for some specific markers; the problem of not considering chemical toxicity of uranium in the texts regulating its incorporation.

Assessing potential risks from exposure to natural uranium in well water

International Nuclear Information System (INIS)

Hakonson-Hayes, A.C.; Fresquez, P.R.; Whicker, F.W.

2002-01-01

Over 50% of the wells in the Nambe region of northern New Mexico exceed the US Environmental Protection Agency's recommended drinking water standard of 20 μg l -1 for 238 U; the highest in the area was measured at 1200 μg U l -1 . Uranium uptake was estimated in tomato (Lycopersicon esculentum), squash (Cucurbita pepo), lettuce (Lactuca scarriola), and radish (Raphanus sativus) irrigated with Nambe well water containing -1 . Plant uptake and human dose and toxicity associated with ingestion of water and produce and inhalation of irrigated soil related to gardening activities were evaluated. Uranium concentration in plants increased linearly with increasing U concentration in irrigation water, particularly in lettuce and radish. The estimated total committed effective dose for 70 years of maximum continuous exposure, via the three pathways to well water containing 1200 μg U l -1 , was 0.17 mSv with a corresponding kidney concentration of 0.8 μg U g -1 kidney

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

Yellowcake: the international uranium cartel

International Nuclear Information System (INIS)

Taylor, J.H.; Yokell, M.D.

1979-01-01

The dramatic events that occurred in the uranium market between 1972 and 1976, and their repercussions is discussed. In particular, the book concentrates on the international uranium cartel's attempt to fix yellowcake prices. The background of the yellowcake industry is discussed in Part I of the book, and the demand for uranium and the nuclear fuel cycle isdiscussed, along with a brief anecdotal history of the uranium industry. Part II describes the political conflicts in Australia which led to the public exposure of the uranium cartel and the situation in the world uranium market that led to the cartel's formation. The legal repercussions of the cartel's exposure are discussed in Part III, and in Part IV, the authors reflect on the ramifications of the events described in the book and some of the issues they raise

Chronic Exposure to Subtherapeutic Antibiotics Aggravates Ischemic Stroke Outcome in Mice

Directory of Open Access Journals (Sweden)

Xiao-Hui Dong

2017-10-01

Full Text Available Subtherapeutic antibiotics have been widely used in agriculture since the 1950s, which can be accumulated in human body through various approaches and may have long-term consequences. However, there is limited information about the link between chronic subtherapeutic antibiotic exposure and the outcome of ischemic brain injury. Here we showed that long-term treatment with subtherapeutic chlortetracycline, penicillin or vancomycin, which were widely used in agriculture approved by US Food and Drug Administration (FDA, could impair EPC functions, reduce ischemic brain angiogenesis and aggravate cerebral ischemic injury and long-term stroke outcomes in mice. In addition, transplantated EPCs from chronic antibiotic-treated mice showed a lower therapeutic effect on cerebral ischemic injury reduction and local angiogenesis promotion compared to those from control mice, and EPCs from the donor animals could integrate into the recipient ischemic brain in mice. Furthermore, transplanted EPCs might exert paracrine effects on cerebral ischemic injury reduction in mice, which could be impaired by chronic antibiotic exposure. In conclusion, chronic subtherapeutic antibiotic exposure aggravated cerebral ischemic injury in mice, which might be partly attributed to the impairment of both EPC-mediated angiogenesis and EPCs' paracrine effects. These findings reveal a previously unrecognized impact of chronic subtherapeutic antibiotic exposure on ischemic injury.

Unexpected Lack of Deleterious Effects of Uranium on Physiological Systems following a Chronic Oral Intake in Adult Rat

Directory of Open Access Journals (Sweden)

Isabelle Dublineau

2014-01-01

Full Text Available Uranium level in drinking water is usually in the range of microgram-per-liter, but this value may be as much as 100 to 1000 times higher in some areas, which may raise question about the health consequences for human populations living in these areas. Our purpose was to improve knowledge of chemical effects of uranium following chronic ingestion. Experiments were performed on rats contaminated for 9 months via drinking water containing depleted uranium (0.2, 2, 5, 10, 20, 40, or 120 mg/L. Blood biochemical and hematological indicators were measured and several different types of investigations (molecular, functional, and structural were conducted in organs (intestine, liver, kidneys, hematopoietic cells, and brain. The specific sensitivity of the organs to uranium was deduced from nondeleterious biological effects, with the following thresholds (in mg/L: 0.2 for brain, >2 for liver, >10 for kidneys, and >20 for intestine, indicating a NOAEL (No-Observed-Adverse-Effect Level threshold for uranium superior to 120 m g/L. Based on the chemical uranium toxicity, the tolerable daily intake calculation yields a guideline value for humans of 1350 μg/L. This value was higher than the WHO value of 30 μg/L, indicating that this WHO guideline for uranium content in drinking water is very protective and might be reconsidered.

Unexpected lack of deleterious effects of uranium on physiological systems following a chronic oral intake in adult rat.

Science.gov (United States)

Dublineau, Isabelle; Souidi, Maâmar; Gueguen, Yann; Lestaevel, Philippe; Bertho, Jean-Marc; Manens, Line; Delissen, Olivia; Grison, Stéphane; Paulard, Anaïs; Monin, Audrey; Kern, Yseult; Rouas, Caroline; Loyen, Jeanne; Gourmelon, Patrick; Aigueperse, Jocelyne

2014-01-01

Uranium level in drinking water is usually in the range of microgram-per-liter, but this value may be as much as 100 to 1000 times higher in some areas, which may raise question about the health consequences for human populations living in these areas. Our purpose was to improve knowledge of chemical effects of uranium following chronic ingestion. Experiments were performed on rats contaminated for 9 months via drinking water containing depleted uranium (0.2, 2, 5, 10, 20, 40, or 120 mg/L). Blood biochemical and hematological indicators were measured and several different types of investigations (molecular, functional, and structural) were conducted in organs (intestine, liver, kidneys, hematopoietic cells, and brain). The specific sensitivity of the organs to uranium was deduced from nondeleterious biological effects, with the following thresholds (in mg/L): 0.2 for brain, >2 for liver, >10 for kidneys, and >20 for intestine, indicating a NOAEL (No-Observed-Adverse-Effect Level) threshold for uranium superior to 120 m g/L. Based on the chemical uranium toxicity, the tolerable daily intake calculation yields a guideline value for humans of 1350 μg/L. This value was higher than the WHO value of 30 μg/L, indicating that this WHO guideline for uranium content in drinking water is very protective and might be reconsidered.

Depleted uranium induces sex- and tissue-specific methylation patterns in adult zebrafish

International Nuclear Information System (INIS)

Gombeau, Kewin; Pereira, Sandrine; Ravanat, Jean-Luc; Camilleri, Virginie; Cavalie, Isabelle; Bourdineaud, Jean-Paul; Adam-Guillermin, Christelle

2016-01-01

We examined the effects of chronic exposure to different concentrations (2 and 20 μg L"−"1) of environmentally relevant waterborne depleted uranium (DU) on the DNA methylation patterns both at HpaII restriction sites (5′-CCGG-3′) and across the whole genome in the zebrafish brain, gonads, and eyes. We first identified sex-dependent differences in the methylation level of HpaII sites after exposure. In males, these effects were present as early as 7 days after exposure to 20 μg L"−"1 DU, and were even more pronounced in the brain, gonads, and eyes after 24 days. However, in females, hypomethylation was only observed in the gonads after exposure to 20 μg L"−"1 DU for 24 days. Sex-specific effects of DU were also apparent at the whole-genome level, because in males, exposure to 20 μg L"−"1 DU for 24 days resulted in cytosine hypermethylation in the brain and eyes and hypomethylation in the gonads. In contrast, in females, hypermethylation was observed in the brain after exposure to both concentrations of DU for 7 days. Based on our current knowledge of uranium toxicity, several hypotheses are proposed to explain these findings, including the involvement of oxidative stress, alteration of demethylation enzymes and the calcium signaling pathway. This study reports, for the first time, the sex- and tissue-specific epigenetic changes that occur in a nonhuman organism after exposure to environmentally relevant concentrations of uranium, which could induce transgenerational epigenetic effects. - Highlights: • This study demonstrates a sex-related effect of DU exposure on DNA methylation patterns. • Impacts on DNA methylation patterns revealed a tissue-specific effect of DU exposure. • The MS–AFLP and HPLC–MS/MS sensitively and complementarily demonstrated the responses to environmental concentrations of DU.

Hypertension and hematologic parameters in a community near a uranium processing facility

International Nuclear Information System (INIS)

Wagner, Sara E.; Burch, James B.; Bottai, Matteo; Pinney, Susan M.; Puett, Robin; Porter, Dwayne; Vena, John E.; Hebert, James R.

2010-01-01

Background: Environmental uranium exposure originating as a byproduct of uranium processing can impact human health. The Fernald Feed Materials Production Center functioned as a uranium processing facility from 1951 to 1989, and potential health effects among residents living near this plant were investigated via the Fernald Medical Monitoring Program (FMMP). Methods: Data from 8216 adult FMMP participants were used to test the hypothesis that elevated uranium exposure was associated with indicators of hypertension or changes in hematologic parameters at entry into the program. A cumulative uranium exposure estimate, developed by FMMP investigators, was used to classify exposure. Systolic and diastolic blood pressure and physician diagnoses were used to assess hypertension; and red blood cells, platelets, and white blood cell differential counts were used to characterize hematology. The relationship between uranium exposure and hypertension or hematologic parameters was evaluated using generalized linear models and quantile regression for continuous outcomes, and logistic regression or ordinal logistic regression for categorical outcomes, after adjustment for potential confounding factors. Results: Of 8216 adult FMMP participants 4187 (51%) had low cumulative uranium exposure, 1273 (15%) had moderate exposure, and 2756 (34%) were in the high (>0.50 Sievert) cumulative lifetime uranium exposure category. Participants with elevated uranium exposure had decreased white blood cell and lymphocyte counts and increased eosinophil counts. Female participants with higher uranium exposures had elevated systolic blood pressure compared to women with lower exposures. However, no exposure-related changes were observed in diastolic blood pressure or hypertension diagnoses among female or male participants. Conclusions: Results from this investigation suggest that residents in the vicinity of the Fernald plant with elevated exposure to uranium primarily via inhalation exhibited

Hypertension and hematologic parameters in a community near a uranium processing facility

Energy Technology Data Exchange (ETDEWEB)

Wagner, Sara E., E-mail: swagner@uga.edu [College of Public Health, Department of Epidemiology and Biostatistics, Paul D. Coverdell Center for Biomedical and Health Sciences, University of Georgia, 500 D.W. Brooks Drive, Athens, GA 30602-7396 (United States); Burch, James B. [Arnold School of Public Health, Department of Epidemiology and Biostatistics, University of South Carolina, Columbia, SC (United States); South Carolina Statewide Cancer Prevention and Control Program, Columbia, SC (United States); WJB Dorn Veteran' s Affairs Medical Center, Columbia, SC (United States); Bottai, Matteo [Arnold School of Public Health, Department of Epidemiology and Biostatistics, University of South Carolina, Columbia, SC (United States); Pinney, Susan M. [College of Medicine, Department of Environmental Health, University of Cincinnati, Cincinnati, OH (United States); Puett, Robin [Arnold School of Public Health, Department of Epidemiology and Biostatistics, University of South Carolina, Columbia, SC (United States); South Carolina Statewide Cancer Prevention and Control Program, Columbia, SC (United States); Arnold School of Public Health, Department of Environmental Health Sciences, University of South Carolina, Columbia, SC (United States); Porter, Dwayne [Arnold School of Public Health, Department of Environmental Health Sciences, University of South Carolina, Columbia, SC (United States); Vena, John E. [College of Public Health, Department of Epidemiology and Biostatistics, Paul D. Coverdell Center for Biomedical and Health Sciences, University of Georgia, 500 D.W. Brooks Drive, Athens, GA 30602-7396 (United States); Hebert, James R. [Arnold School of Public Health, Department of Epidemiology and Biostatistics, University of South Carolina, Columbia, SC (United States); South Carolina Statewide Cancer Prevention and Control Program, Columbia, SC (United States)

2010-11-15

Background: Environmental uranium exposure originating as a byproduct of uranium processing can impact human health. The Fernald Feed Materials Production Center functioned as a uranium processing facility from 1951 to 1989, and potential health effects among residents living near this plant were investigated via the Fernald Medical Monitoring Program (FMMP). Methods: Data from 8216 adult FMMP participants were used to test the hypothesis that elevated uranium exposure was associated with indicators of hypertension or changes in hematologic parameters at entry into the program. A cumulative uranium exposure estimate, developed by FMMP investigators, was used to classify exposure. Systolic and diastolic blood pressure and physician diagnoses were used to assess hypertension; and red blood cells, platelets, and white blood cell differential counts were used to characterize hematology. The relationship between uranium exposure and hypertension or hematologic parameters was evaluated using generalized linear models and quantile regression for continuous outcomes, and logistic regression or ordinal logistic regression for categorical outcomes, after adjustment for potential confounding factors. Results: Of 8216 adult FMMP participants 4187 (51%) had low cumulative uranium exposure, 1273 (15%) had moderate exposure, and 2756 (34%) were in the high (>0.50 Sievert) cumulative lifetime uranium exposure category. Participants with elevated uranium exposure had decreased white blood cell and lymphocyte counts and increased eosinophil counts. Female participants with higher uranium exposures had elevated systolic blood pressure compared to women with lower exposures. However, no exposure-related changes were observed in diastolic blood pressure or hypertension diagnoses among female or male participants. Conclusions: Results from this investigation suggest that residents in the vicinity of the Fernald plant with elevated exposure to uranium primarily via inhalation exhibited

Effect of pH and Pressure on Uranium Removal from Drinking Water Using NF/RO Membranes.

Science.gov (United States)

Schulte-Herbrüggen, Helfrid M A; Semião, Andrea J C; Chaurand, Perrine; Graham, Margaret C

2016-06-07

Groundwater is becoming an increasingly important drinking water source. However, the use of groundwater for potable purposes can lead to chronic human exposure to geogenic contaminants, for example, uranium. Nanofiltration (NF) and reverse osmosis (RO) processes are used for drinking water purification, and it is important to understand how contaminants interact with membranes since accumulation of contaminants to the membrane surface can lead to fouling, performance decline and possible breakthrough of contaminants. During the current study laboratory experiments were conducted using NF (TFC-SR2) and RO (BW30) membranes to establish the behavior of uranium across pH (3-10) and pressure (5-15 bar) ranges. The results showed that important determinants of uranium-membrane sorption interactions were (i) the uranium speciation (uranium species valence and size in relation to membrane surface charge and pore size) and (ii) concentration polarization, depending on the pH values. The results show that it is important to monitor sorption of uranium to membranes, which is controlled by pH and concentration polarization, and, if necessary, adjust those parameters controlling uranium sorption.

Uranium-bearing wastes and their radon emanation

International Nuclear Information System (INIS)

Sasaki, Tomozo; Imamura, Mitsutaka; Gunji, Yasuyoshi

2007-01-01

There are no data available with regard to radon emanation coefficients for uranium-bearing wastes; such data are needed for the assessment of radiation exposure from radon that will be generated in the distant future as one uranium progeny at shallow land disposal sites for uranium-bearing wastes. There are many kinds of uranium-bearing wastes. However, it is not necessary to measure the radon emanation coefficients for all of them for two reasons. First, the radon emanation coefficients for uranium-bearing wastes contaminated by dissolved uranium are determined by the uranium chemical form, the manner of uranium deposition on the waste matrix, and the size of the particles which constitute the waste matrix. Therefore, only a few representative measurements are sufficient for such uranium-bearing wastes. Second, it is possible to make theoretical calculations of radon emanation coefficients for uranium-bearing wastes contaminated by UO 2 particles before sintering. In the present study, simulated uranium-bearing wastes contaminated by dissolved uranium were prepared, their radon emanation coefficients were measured and radon emanation coefficients were calculated theoretically for uranium-bearing wastes contaminated by UO 2 particles before sintering. The obtained radon emanation coefficients are distributed at higher values than those for ubiquitous soils and rocks in the natural environment. Therefore, it is not correct to just compare uranium concentrations among uranium-bearing wastes, ubiquitous soils and rocks in terms of radiation exposure. The radon emanation coefficients obtained in the present study have to be employed together with the uranium concentration in uranium-bearing wastes in order to achieve proper assessment of radiation exposure. (author)

Chronic bisphenol A exposure alters behaviors of zebrafish (Danio rerio)

International Nuclear Information System (INIS)

Wang, Ju; Wang, Xia; Xiong, Can; Liu, Jian; Hu, Bing; Zheng, Lei

2015-01-01

The adult zebrafish (Danio rerio) were exposed to treated-effluent concentration of bisphenol A (BPA) or 17β-estradiol (E2) for 6 months to evaluate their effects on behavioral characteristics: motor behavior, aggression, group preference, novel tank test and light/dark preference. E2 exposure evidently dampened fish locomotor activity, while BPA exposure had no marked effect. Interestingly, BPA-exposed fish reduced their aggressive behavior compared with control or E2. Both BPA and E2 exposure induced a significant decrease in group preference, as well as a weaker adaptability to new environment, exhibiting lower latency to reach the top, more entries to the top, longer time spent in the top, fewer frequent freezing, and fewer erratic movements. Furthermore, the circadian rhythmicity of light/dark preference was altered by either BPA or E2 exposure. Our results suggest that chronic exposure of treated-effluent concentration BPA or E2 induced various behavioral anomalies in adult fish and enhanced ecological risk to wildlife. - Highlights: • BPA exposure induces various adult behavioral anomalies. • BPA exposure decreases social interaction and environmental adaptation of zebrafish. • BPA exposure increases ecological risk to wildlife. - Chronic bisphenol A exposure alters zebrafish behaviors.

Proteomic analysis reveals contrasting stress response to uranium in two nitrogen-fixing Anabaena strains, differentially tolerant to uranium

Energy Technology Data Exchange (ETDEWEB)

Panda, Bandita; Basu, Bhakti; Acharya, Celin; Rajaram, Hema; Apte, Shree Kumar, E-mail: aptesk@barc.gov.in

2017-01-15

Highlights: • Response of two native cyanobacterial strains to uranium exposure was studied. • Anabaena L-31 exhibited higher tolerance to uranium as compared to Anabaena 7120. • Uranium exposure differentially affected the proteome profiles of the two strains. • Anabaena L-31 showed better sustenance of photosynthesis and carbon metabolism. • Anabaena L-31 displayed superior oxidative stress defense than Anabaena 7120. - Abstract: Two strains of the nitrogen-fixing cyanobacterium Anabaena, native to Indian paddy fields, displayed differential sensitivity to exposure to uranyl carbonate at neutral pH. Anabaena sp. strain PCC 7120 and Anabaena sp. strain L-31 displayed 50% reduction in survival (LD{sub 50} dose), following 3 h exposure to 75 μM and 200 μM uranyl carbonate, respectively. Uranium responsive proteome alterations were visualized by 2D gel electrophoresis, followed by protein identification by MALDI-ToF mass spectrometry. The two strains displayed significant differences in levels of proteins associated with photosynthesis, carbon metabolism, and oxidative stress alleviation, commensurate with their uranium tolerance. Higher uranium tolerance of Anabaena sp. strain L-31 could be attributed to sustained photosynthesis and carbon metabolism and superior oxidative stress defense, as compared to the uranium sensitive Anabaena sp. strain PCC 7120. Significance: Uranium responsive proteome modulations in two nitrogen-fixing strains of Anabaena, native to Indian paddy fields, revealed that rapid adaptation to better oxidative stress management, and maintenance of metabolic and energy homeostasis underlies superior uranium tolerance of Anabaena sp. strain L-31 compared to Anabaena sp. strain PCC 7120.

Uranium: biokinetics and toxicity

International Nuclear Information System (INIS)

Menetrier, F.; Renaud-Salis, V.; Flury-Herard, A.

2000-01-01

This report was achieved as a part of a collaboration with the Fuel Cycle Direction. Its aim was to give the state of the art about: the behaviour of uranium in the human organism (biokinetics) after ingestion, its toxicity (mainly renal) and the current regulation about its incorporation. Both in the upstream and in the downstream of the fuel cycle, uranium remains, quantitatively, the first element in the cycle which is, at the present time, temporarily disposed or recycled. Such a considerable quantity of uranium sets the problem of its risk on the health. In the long term, the biosphere may be affected and consequently the public may ingest water or food contaminated with uranium. In this way, radiological and chemical toxicity risk may be activated. This report emphasizes: the necessity of confirming some experimental and epidemiological biokinetic data used or not in the ICRP models. Unsolved questions remain about the gastrointestinal absorption according to chemical form (valency state, mixtures...), mass and individual variations (age, disease) further a chronic ingestion of uranium. It is well established that uranium is mainly deposited in the skeleton and the kidney. But the skeleton kinetics following a chronic ingestion and especially in some diseases has to be more elucidated; the necessity of taking into account uranium at first as a chemical toxic, essentially in the kidney and determining the threshold of functional lesion. In this way, it is important to look for some specific markers; the problem of not considering chemical toxicity of uranium in the texts regulating its incorporation

Assessing potential risks from exposure to natural uranium in well water

Energy Technology Data Exchange (ETDEWEB)

Hakonson-Hayes, A.C.; Fresquez, P.R. E-mail: fresquezp@lanl.gov; Whicker, F.W

2002-07-01

Over 50% of the wells in the Nambe region of northern New Mexico exceed the US Environmental Protection Agency's recommended drinking water standard of 20 {mu}g l{sup -1} for {sup 238}U; the highest in the area was measured at 1200 {mu}g U l{sup -1}. Uranium uptake was estimated in tomato (Lycopersicon esculentum), squash (Cucurbita pepo), lettuce (Lactuca scarriola), and radish (Raphanus sativus) irrigated with Nambe well water containing <1, 150, 500, and 1200 {mu}g U l{sup -1}. Plant uptake and human dose and toxicity associated with ingestion of water and produce and inhalation of irrigated soil related to gardening activities were evaluated. Uranium concentration in plants increased linearly with increasing U concentration in irrigation water, particularly in lettuce and radish. The estimated total committed effective dose for 70 years of maximum continuous exposure, via the three pathways to well water containing 1200 {mu}g U l{sup -1}, was 0.17 mSv with a corresponding kidney concentration of 0.8 {mu}g U g{sup -1} kidney.

A novel antibody-based biomarker for chronic algal toxin exposure and sub-acute neurotoxicity

Science.gov (United States)

Lefebvre, Kathi A.; Frame, Elizabeth R.; Gulland, Frances; Hansen, John D.; Kendrick, Preston S.; Beyer, Richard P.; Bammler, Theo K.; Farin, Frederico M.; Hiolski, Emma M.; Smith, Donald R.; Marcinek, David J.

2012-01-01

The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by seizures, memory loss, coma and death. Regular monitoring for high DA levels in edible shellfish tissues has been effective in protecting human consumers from acute DA exposure. However, chronic low-level DA exposure remains a concern, particularly in coastal and tribal communities that subsistence harvest shellfish known to contain low levels of the toxin. Domoic acid exposure via consumption of planktivorous fish also has a profound health impact on California sea lions (Zalophus californianus) affecting hundreds of animals yearly. Due to increasing algal toxin exposure threats globally, there is a critical need for reliable diagnostic tests for assessing chronic DA exposure in humans and wildlife. Here we report the discovery of a novel DA-specific antibody response that is a signature of chronic low-level exposure identified initially in a zebrafish exposure model and confirmed in naturally exposed wild sea lions. Additionally, we found that chronic exposure in zebrafish caused increased neurologic sensitivity to DA, revealing that repetitive exposure to DA well below the threshold for acute behavioral toxicity has underlying neurotoxic consequences. The discovery that chronic exposure to low levels of a small, water-soluble single amino acid triggers a detectable antibody response is surprising and has profound implications for the development of diagnostic tests for exposure to other pervasive environmental toxins.

A novel antibody-based biomarker for chronic algal toxin exposure and sub-acute neurotoxicity.

Science.gov (United States)

Lefebvre, Kathi A; Frame, Elizabeth R; Gulland, Frances; Hansen, John D; Kendrick, Preston S; Beyer, Richard P; Bammler, Theo K; Farin, Frederico M; Hiolski, Emma M; Smith, Donald R; Marcinek, David J

2012-01-01

The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by seizures, memory loss, coma and death. Regular monitoring for high DA levels in edible shellfish tissues has been effective in protecting human consumers from acute DA exposure. However, chronic low-level DA exposure remains a concern, particularly in coastal and tribal communities that subsistence harvest shellfish known to contain low levels of the toxin. Domoic acid exposure via consumption of planktivorous fish also has a profound health impact on California sea lions (Zalophus californianus) affecting hundreds of animals yearly. Due to increasing algal toxin exposure threats globally, there is a critical need for reliable diagnostic tests for assessing chronic DA exposure in humans and wildlife. Here we report the discovery of a novel DA-specific antibody response that is a signature of chronic low-level exposure identified initially in a zebrafish exposure model and confirmed in naturally exposed wild sea lions. Additionally, we found that chronic exposure in zebrafish caused increased neurologic sensitivity to DA, revealing that repetitive exposure to DA well below the threshold for acute behavioral toxicity has underlying neurotoxic consequences. The discovery that chronic exposure to low levels of a small, water-soluble single amino acid triggers a detectable antibody response is surprising and has profound implications for the development of diagnostic tests for exposure to other pervasive environmental toxins.

Drinking-water criteria document for uranium. Draft report

International Nuclear Information System (INIS)

1991-06-01

The document provides the health effects basis to be considered in establishing the MCLG for uranium. To achieve the objective, data on pharmacokinetics, human exposure, acute and chronic toxicity to animals and humans, epidemiology and the mechanisms of toxicity were evaluated. Specific emphasis is placed on literature data providing dose-response information. Thus, while the literature search and evaluation performed in support of the document was comprehensive, only the reports considered most pertinent in the derivation of the MCLG are cited in the document. The comprehensive literature search in support of the analysis of health effects, exposure and occurrence in the document includes information published up to January, 1991; however, more recent information may have been added during the review process

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

Oxidative stress responses induced by uranium exposure at low pH in leaves of Arabidopsis thaliana plants

International Nuclear Information System (INIS)

Saenen, Eline; Horemans, Nele; Vanhoudt, Nathalie; Vandenhove, Hildegarde; Biermans, Geert; Hees, May van; Wannijn, Jean; Vangronsveld, Jaco; Cuypers, Ann

2015-01-01

Anthropogenic activities have led to a widespread uranium (U) contamination in many countries. The toxic effects of U at the cellular level have mainly been investigated at a pH around 5.5, the optimal pH for hydroponically grown plants. However, since the speciation of U, and hence its toxicity, is strongly dependent on environmental factors such as the pH, it is important to investigate the effects of U at different environmentally relevant pH levels. Although U is poorly translocated from the roots to the shoots, resulting in a low U concentration in the leaves, it has been demonstrated that toxic effects in the leaves were already visible after 1 day exposure at pH 5.5, although only when exposed to relatively high U concentrations (100 μM). Therefore, the present study aimed to analyse the effects of different U concentrations (ranging from 0 to 100 μM) at pH 4.5 in leaves of Arabidopsis thaliana plants. Results indicate that U induces early senescence in A. thaliana leaves as was suggested by a decreased expression of CAT2 accompanied by an induction of CAT3 expression, a decreased CAT capacity and an increased lipid peroxidation. In addition, miRNA398b/c is involved in the regulation of the SOD response in the leaves. As such, an increased MIR398b/c expression was observed leading to a decreased transcript level of CSD1/2. Finally, the biosynthesis of ascorbate was induced after U exposure. This can point towards an important role for this metabolite in the scavenging of reactive oxygen species under U stress. - Highlights: • Uranium induces early senescence in A. thaliana after uranium exposure. • Ascorbate is involved in scavenging reactive oxygen species under uranium stress. • miRNA398b/c is involved in the regulation of the SOD response under uranium stress.

Radiological impacts of uranium recovery in the phosphate industry

International Nuclear Information System (INIS)

Ryan, M.T.

1981-01-01

This article characterizes the occupational and public radiological health impacts associated with phosphate mining and milling. These impacts are related to the phosphate industry's uranium production potential and are compared with those associated with conventional uranium mining and milling. The radiological impacts resulting from occupational and nonoccupational exposures are assessed. Occupational exposures in phosphate facilities are compared to background exposures and radiological population dose assessments, which characterize important radionuclides and exposure pathways. The following conclusions were reached: (1) public consequences of phosphate mining will occur whether or not uranium is recovered as a by-product, (2) radiological consequences of phosphate mining may be comparable to those associated with uranium mining and milling per unit uranium production, (3) radiological impacts via surface waterways and crops fertilized with uranium-bearing phosphates are of minor consequence, and (4) major radiological public health problems associated with phosphate mining are related to radon and radon progeny exposures in structures built on reclaimed lands or with phosphate mining residues, although the magnitudes of these impacts are difficult to evaluate with current data

77 FR 14837 - Bioassay at Uranium Mills

Science.gov (United States)

2012-03-13

... NUCLEAR REGULATORY COMMISSION [NRC-2012-0057] Bioassay at Uranium Mills AGENCY: Nuclear Regulatory..., ``Bioassay at Uranium Mills.'' This guide describes a bioassay program acceptable to the NRC staff for uranium mills and applicable portions of uranium conversion facilities where the possibility of exposure...

Brick mortar exposure and chronic lymphocytic leukemia.

Science.gov (United States)

Markovic-Denic, L; Jankovic, S; Marinkovic, J; Radovanovic, Z

1995-01-01

A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL.

Brick mortar exposure and chronic lymphocytic leukemia

International Nuclear Information System (INIS)

Markovic-Denic, Lj.; Jankovic, S.; Marinkovic, J.; Radovanovic, Z.

1995-01-01

A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence, (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL. (author)

Incidence of non-lung solid cancers in Czech uranium miners: A case-cohort study

International Nuclear Information System (INIS)

Kulich, M.; Rericha, V.; Rericha, R.; Shore, D.L.; Sandler, D.P.

2011-01-01

Objectives: Uranium miners are chronically exposed to radon and its progeny, which are known to cause lung cancer and may be associated with leukemia. This study was undertaken to evaluate risk of non-lung solid cancers among uranium miners in Pribram region, Czech Republic. Methods: A retrospective stratified case-cohort study in a cohort of 22,816 underground miners who were employed between 1949 and 1975. All incident non-lung solid cancers were ascertained among miners who worked underground for at least 12 months (n=1020). A subcohort of 1707 subjects was randomly drawn from the same population by random sampling stratified on age. The follow-up period lasted from 1977 to 1996. Results: Relative risks comparing 180 WLM (90th percentile) of cumulative lifetime radon exposure to 3 WLM (10th percentile) were 0.88 for all non-lung solid cancers combined (95% CI 0.73-1.04, n=1020), 0.87 for all digestive cancers (95% CI 0.69-1.09, n=561), 2.39 for gallbladder cancer (95% CI 0.52-10.98, n=13), 0.79 for larynx cancer (95% CI 0.38-1.64, n=62), 2.92 for malignant melanoma (95% CI 0.91-9.42, n=23), 0.84 for bladder cancer (95% CI 0.43-1.65, n=73), and 1.13 for kidney cancer (95% CI 0.62-2.04, n=66). No cancer type was significantly associated with radon exposure; only malignant melanoma and gallbladder cancer showed elevated but non-significant association with radon. Conclusions: Radon was not significantly associated with incidence of any cancer of interest, although a positive association of radon with malignant melanoma and gallbladder cancer cannot be entirely ruled out. - Research highlights: → Uranium miners are chronically exposed to radon. → We evaluate risk of non-lung solid cancers among uranium miners. → No cancer type was significantly associated with radon exposure. → Malignant melanoma and gallbladder cancer showed non-significant elevated risk.

Occupational diseases in uranium and ore miners in connection with radiation exposure in the Czech Republic

International Nuclear Information System (INIS)

Mueller, T.

2003-01-01

Dozens cases of diseases are submitted to judgement as occupational diseases every year in the Czech Republic. Patients or attending physicians suggest that these cases are caused by occupational ionizing radiation. Only a part of these cases is qualified as occupational disease. The term 'occupational disease' is rather a juridical term which underlies the right to financial compensation. The causal association with exposure to ionizing radiation cannot be indisputably verified by expert medical opinion. Most diseases, which are proposed as occupational disease, are malignant tumors of the lungs. Total majority of judged cases are lung cancers from radioactive agents. In 2002, a total of 33 cases of lung cancer in former uranium or ore miners have been acknowledged as occupational diseases. The decision about occupational disease is derived from probabilistic approach based on estimation of probability of causation of irradiation on disease origin (methodical guideline No. 15 of Ministry of Health Bulletin, part 9, 1998). The presented paper gives a general information about all judged causes of occupational diseases in former uranium and ore miners in the Czech Republic in 2002. A total of 72 cases were submitted to judgement of conditions of disease origin to the National Radiation Protection Institute in 2002. 67 cases were lung cancers, 1 case was chronic myeloid leukemia, acute myeloid leukemia, basaliom, cancer of larynx and cancer of nasal septum. The probability of causation was assessed as prevailing in 32 cases of lung cancer, borderline in 5 cases and low in other 30 cases of lung cancer. The probability of causation was prevailing in both cases of myeloid leukemia. (author)

Does chronic exposure to mobile phones affect cognition?

Science.gov (United States)

Mohan, Mamta; Khaliq, Farah; Panwar, Aprajita; Vaney, Neelam

2016-01-01

Summary Mobile phones form an integral part of our modern lifestyle. Following the drastic rise in mobile phone use in recent years, it has become important to study its potential public health impact. Amongst the various mobile phone health hazards, the most alarming is the possible effect on the brain. The aim of the present study was to explore whether chronic exposure to mobile phones affects cognition. Ninety subjects aged 17–25 years with normal hearing were recruited for the study and divided into three groups according to their duration of mobile phone use. No significant differences in N100, P200, N200, P300 latencies or N2-P300 amplitude were observed. Our results suggest that chronic mobile phone exposure does not have detrimental effects on cognition. PMID:27027894

In vivo effects of chronic contamination with depleted uranium on CYP3A and associated nuclear receptors PXR and CAR in the rat

International Nuclear Information System (INIS)

Souidi, M.; Gueguen, Y.; Linard, C.; Dudoignon, N.; Grison, S.; Baudelin, C.; Marquette, C.; Gourmelon, P.; Aigueperse, J.; Dublineau, I.

2005-01-01

In addition to its natural presence at high concentrations in some areas, uranium has several civilian and military applications that could cause contamination of human populations, mainly through chronic ingestion. Reports describe the accumulation of this radionuclide in some organs (including the bone, kidney, and liver) after acute or chronic contamination and show that it produces chemical or radiological toxicity or both. The literature is essentially devoid of information about uranium-related cellular and molecular effects on metabolic functions such as xenobiotic detoxification. The present study thus evaluated rats chronically exposed to depleted uranium in their drinking water (1 mg/(rat day)) for 9 months. Our specific aim was to evaluate the hepatic and extrahepatic mRNA expression of CYP3A1/A2, CYP2B1, and CYP1A1 as well as of the nuclear receptors PXR, CAR, and RXR in these rats. CYP3A1 mRNA expression was significantly higher in the brain (200%), liver (300%), and kidneys (900%) of exposed rats compared with control rats, while CYP3A2 mRNA levels were higher in the lungs (300%) and liver (200%), and CYP2B1 mRNA expression in the kidneys (300%). Expression of CYP1A1 mRNA did not change significantly during this study. PXR mRNA levels increased in the brain (200%), liver (150%), and kidneys (200%). Uranium caused CAR mRNA expression in the lungs to double. Expression of RXR mRNA did not change significantly in the course of this study, nor did the hepatic activity of CYP2C, CYP3A, CYP2A, or CYP2B. Uranium probably affects the expression of drug-metabolizing CYP enzymes through the PXR and CAR nuclear receptors. These results suggest that the stimulating effect of uranium on these enzymes might lead to hepatic or extrahepatic toxicity (or both) during drug treatment and then affect the entire organism

Brick mortar exposure and chronic lymphocytic leukemia

Energy Technology Data Exchange (ETDEWEB)

Markovic-Denic, Lj; Jankovic, S [Institute of Epidemiology, Faculty of Medicine, Belgrade (Yugoslavia); Marinkovic, J [Institute of Social Medicine, Statistics and Healt Research, Faculty of Medicine, Belgrade (Yugoslavia); Radovanovic, Z [Department of Community Medicine and Behavioural Sciences, Faculty of Medicine, 13110 Safat (Kuwait)

1996-12-31

A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence, (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL. (author) 1 tab., 30 refs.

Sensitivity of Trout to Chronic Acute Exposure to Selenium

DEFF Research Database (Denmark)

Nielsen, Gunnar Gissel; Nielsen, M. Gissel

1978-01-01

Trout were exposed to selenite (Na2SeO3) solutions of varying concentrations (0.1-100 ppm Se) for periods of up to 4 wk. A chronic exposure to 0.1 ppm Se or less is non-lethal to trout. Lethality at higher concentrations depends on the length of exposure. Trout that survive for 10 days in tap...

Comparative study of radon exposure in Canadian homes and uranium mines - a discussion on the importance of national radon program

International Nuclear Information System (INIS)

Chen, Jing

2017-01-01

The history of lung cancer in uranium miners is well known for over hundreds of years when the disease was referred to as 'miner's disease' or 'mountain sickness'. Radon levels in uranium mines have decreased significantly over the past 30 years as a result of effective radiation protection measures at workplaces. For the most recent 10-year period, the average radon concentrations to underground and surface workers in Canadian uranium mines were 111 and 11 Bq m -3 , respectively. Based on the recent radon survey carried out in roughly 14 000 homes in 121 health regions across Canada and the more recent radon and thoron survey in 33 Canadian cities and 4000 homes, the average radon concentration in Canadian homes is 77 Bq m -3 . This study demonstrates that, nowadays, workers are exposed to radon in underground mines at a comparable radon level to what Canadians are exposed to at home. Since exposure to indoor radon is the main source of natural radiation exposure to the population, it is important for the National Radon Program to further increase radon awareness, and to encourage more Canadians to take appropriate actions to reduce radon exposure. (authors)

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

Health concerns in uranium mining and milling

International Nuclear Information System (INIS)

Archer, V.E.

1981-01-01

Mortality of uranium miners from both lung cancer and other respiratory diseases is strongly dependent on exposure to radon daughters, cigarette smoking and height. Lung cancer among 15 different mining groups (uranium, iron, lead, zinc) was analyzed to determine what factors influence incidence and the induction-latent period. At low exposure or exposure rates, alpha radiation is more efficient in inducing lung cancer, producing an upward convex exposure-response curve. The induction-latent period is shortened by increased age at start of mining, by cigarette smoking and by high exposure rates. Instead of extrapolating downward from high exposures to estimate risk at low levels, it is suggested that it might be more appropriate to use cancer rates associated with background radiation as the lowest point on the exposure-response curve. Although health risks are much greater in uranium mines than mills, there is some health risk in the mills from long-lived radioactive materials

Adaptive response of Chironomus riparius populations exposed to uranium contaminated sediments during consecutive generations

International Nuclear Information System (INIS)

Dias, V.

2010-01-01

The intensity of selection on populations caused by polluted environment often exceeds which is caused by an unpolluted environment. Therefore, micro evolution can occur in response to this anthropic-directional force over a short period. In this context, this thesis focused on studying phenotypic changes in Chironomus riparius populations exposed during several consecutive generations to uranium-contaminated sediments. In laboratory-controlled conditions experiments were conducted with same origin populations exposed to a range of uranium concentration inducing toxic effects. Over eight-generations of exposure, life-history traits measures revealed micro evolution in exposed populations, including increase of adult reproductive success. Other experiments (acute toxicity test, common garden experiment) performed in parallel enabled to link these micro evolution with a tolerance induction, as a consequence of genetic adaptation. Nonetheless this adaptation also induced cost in terms of fitness and genetic diversity for pre-exposed populations. These results lead to the hypothesis of a selection by uranium that acted sequentially on populations. They also underline the need to better-understand the adaptive mechanisms to better assess the ecological consequences of chronic exposure of populations to a pollutant. (author)

Occupational exposure and risk of chronic obstructive pulmonary disease: a systematic review and meta-analysis.

Science.gov (United States)

Alif, Sheikh M; Dharmage, Shyamali C; Bowatte, Gayan; Karahalios, Amalia; Benke, Geza; Dennekamp, Martine; Mehta, Amar J; Miedinger, David; Künzli, Nino; Probst-Hensch, Nicole; Matheson, Melanie C

2016-08-01

Due to contradictory literature we have performed a systematic review and meta-analyse of population-based studies that have used Job Exposure Matrices to assess occupational exposure and risk of Chronic Obstructive Pulmonary Disease (COPD). Two researchers independently searched databases for published articles using predefined inclusion criteria. Study quality was assessed, and results pooled for COPD and chronic bronchitis for exposure to biological dust, mineral dust, and gases/fumes using a fixed and random effect model. Five studies met predetermined inclusion criteria. The meta-analysis showed low exposure to mineral dust, and high exposure to gases/fumes were associated with an increased risk of COPD. We also found significantly increased the risk of chronic bronchitis for low and high exposure to biological dust and mineral dust. Expert commentary: The relationship between occupational exposure assessed by the JEM and the risk of COPD and chronic bronchitis shows significant association with occupational exposure. However, the heterogeneity of the meta-analyses suggests more wide population-based studies with older age groups and longitudinal phenotype assessment of COPD to clarify the role of occupational exposure to COPD risk.

Investigations Into the Reusability of Amidoxime-Based Polymeric Uranium Adsorbents

Energy Technology Data Exchange (ETDEWEB)

Kuo, Li-Jung [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Science Lab.; Gill, Gary A. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Science Lab.; Strivens, Jonathan E. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Science Lab.; Wood, Jordana R. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Science Lab.; Schlafer, Nicholas J. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Science Lab.; Wai, Chien M. [Univ. of Idaho, Moscow, ID (United States); LCW Supercritical Technologies, Seattle, WA (United States); Pan, H. B. [Univ. of Idaho, Moscow, ID (United States)

2016-09-28

Significant advancements in amidoxime-based polymeric adsorbents to extract uranium from seawater are achieved in recent years. The success of uranium adsorbent development can help provide a sustainable supply of fuel for nuclear reactors. To bring down the production cost of this new technology, in addition to the development of novel adsorbents with high uranium capacity and manufacture cost, the development of adsorbent re-using technique is critical because it can further reduce the cost of the adsorbent manufacture. In our last report, the use of high concentrations of bicarbonate solution (3M KHCO3) was identified as a cost-effective, environmental friendly method to strip uranium from amidoxime-based polymeric adsorbents. This study aims to further improve the method for high recovery of uranium capacity in re-uses and to evaluate the performance of adsorbents after multiple re-use cycles. Adsorption of dissolved organic matter (DOM) on the uranium adsorbents during seawater exposure can hinder the uranium adsorption and slow down the adsorption rate. An additional NaOH rinse (0.5 M NaOH, room temperature) was applied after the 3 M KHCO3 elution to remove natural organic matter from adsorbents. The combination of 3 M KHCO3 elution and 0.5 M NaOH rinse significantly improves the recovery of uranium adsorption capacity in the re-used adsorbents. In the first re-use, most ORNL adsorbents tested achieve ~100% recovery by using 3 M KHCO3 elution + 0.5 M NaOH rinse approach, in comparison to 54% recovery when only 3 M KHCO3 elution was applied. A significant drop in capacity was observed when the adsorbents went through more than one re-use. FTIR spectra revealed that degradation of amidoxime ligands occurs during seawater exposure, and is more significant the longer the exposure time. Significantly elevated ratios of Ca/U and Mg/U in re-used adsorbents support the decrease in abundance of amidoxime ligands and increase carboxylate group from FT-IR analysis. The

Radiation protection in uranium mining and milling industry

International Nuclear Information System (INIS)

Raghavayya, M.

2005-01-01

The first phase of the Nuclear Fuel Cycle is exploration for uranium and the next is mining and milling of uranium ore. This phase is mostly characterised by low levels of radioactivity and radiation exposure of the workers involved. Yet it is a paradoxical truth that incidence of cancer among the work force, especially miners, due to occupational radiation exposure (from radon and decay products) has been proved only in uranium mines in the entire Nuclear Fuel Cycle. Of course such incidence occurred before the detrimental effect of radiation exposure was realised and understood. Therefore it is important to familiarise oneself with the radiation hazards prevalent in the uranium mining and milling facilities so as to take appropriate remedial measures for the protection of not only the workers but also the public at large. There are both open cast and underground uranium mines around the world. Radiation hazards are considerably less significant in open cast mines than in underground mines unless the ore grade is very high. By default therefore the discussion which ensues relates mainly to radiation hazards in underground uranium mines and associated milling operations. The discussion gives a brief outline of typical uranium mine and mining and milling operations. This is followed by a description of the radiation hazards therein and protection measures that are to be taken to minimise radiation exposure. (author)

Chronic exposure to organophosphate (OP) pesticides and neuropsychological functioning in farm workers: a review.

Science.gov (United States)

Muñoz-Quezada, María Teresa; Lucero, Boris Andrés; Iglesias, Verónica Paz; Muñoz, María Pía; Cornejo, Claudia Alejandra; Achu, Eduardo; Baumert, Brittney; Hanchey, Arianna; Concha, Carlos; Brito, Ana María; Villalobos, Marcos

2016-01-01

Previous studies have demonstrated that acute poisoning from exposure to organophosphate (OP) pesticides in agricultural workers causes adverse health effects. However, neuropsychological and cognitive effects of chronic occupational exposure to OP pesticides remain controversial. To identify, evaluate, and systematize existing evidence regarding chronic exposure to OP pesticides and neuropsychological effects in farmworkers. Using the PubMed search engine, a systematic review process was implemented and replicated according to the PRISMA statement. Eligibility criteria included workers over 18 years of age exposed to OP pesticides as well as assessment of neuropsychological and cognitive functioning. Search terms were in English and Spanish languages and included organophosphate and workers. Of the search results, 33 of 1,256 articles meet eligibility criteria. Twenty-four studies found an association between chronic occupational exposure to OP pesticides and low neuropsychological performance in workers. We classified nine of the studies to have study design limitations. Studies indicated occupational exposure to OP pesticides is linked to difficulties in executive functions, psychomotor speed, verbal, memory, attention, processing speed, visual-spatial functioning, and coordination. Nine studies find no relationship between OP pesticides exposure and neuropsychological performance. Overall, evidence suggests an association between chronic occupational exposure to OP pesticides and neuropsychological effects. However, there is no consensus about the specific cognitive skills affected.

Chronic particulate exposure, mortality and cardiovascular outcomes in the nurses health study

Science.gov (United States)

Adverse health effects of exposures to acute air pollution have been well studied. Fewer studies have examined effects of chronic exposure. Previous studies used exposure estimates for narrow time periods and were limited by the geographic distribution of pollution monitors. This...

Health concerns in uranium mining and milling

International Nuclear Information System (INIS)

Archer, V.E.

1981-01-01

Mortality of uranium miners form both lung cancer and other respiratory diseases is strongly dependent on exposure to radon daughters, cigarette smoking and height. Lung cancer among 15 different mining groups (uranium, iron, led, zinc) was analyzed to determine what factors influence incidence and the induction-latent period. At low exposure or exposure rates, alpha radiation is more efficient in inducing lung cancer, producing an upward convex exposure-response curve. The induction-latent period is shortened by increased age at start of mining, by cigarette smoking and by high exposure rates. For a follow-up period of 20 to 25 years, the incidence increases with age at start of mining, with magnitude of exposure and with amount of cigarette smoking. Instead of extrapolating downward from high exposures to estimate risk at low levels, it is suggested that it might be more appropriate to use cancer rates associated with background radiation as the lowest point on the exposure-response curve. Although health risks are much greater in uranium mines than mills, there is some health risk in the mills from long-lived radioactive materials

Influence of depleted uranium on hepatic cholesterol metabolism in apolipoprotein E-deficient mice.

Science.gov (United States)

Souidi, M; Racine, R; Grandcolas, L; Grison, S; Stefani, J; Gourmelon, P; Lestaevel, P

2012-04-01

Depleted uranium (DU) is uranium with a lower content of the fissile isotope U-235 than natural uranium. It is a radioelement and a waste product from the enrichment process of natural uranium. Because of its very high density, it is used in the civil industry and for military purposes. DU exposure can affect many vital systems in the human body, because in addition to being weakly radioactive, uranium is a toxic metal. It should be emphasized that, to be exposed to radiation from DU, you have to eat, drink, or breathe it, or get it on your skin. This particular study is focusing on the health effects of DU for the cholesterol metabolism. Previous studies on the same issue have shown that the cholesterol metabolism was modulated at molecular level in the liver of laboratory rodents contaminated for nine months with DU. However, this modulation was not correlated with some effects at organs or body levels. It was therefore decided to use a "pathological model" such as hypercholesterolemic apolipoprotein E-deficient laboratory mice in order to try to clarify the situation. The purpose of the present study is to assess the effects of a chronic ingestion (during 3 months) of a low level DU-supplemented water (20 mg L(-1)) on the above mentioned mice in order to determine a possible contamination effect. Afterwards the cholesterol metabolism was studied in the liver especially focused on the gene expressions of cholesterol-catabolising enzymes (CYP7A1, CYP27A1 and CYP7B1), as well as those of associated nuclear receptors (LXRα, FXR, PPARα, and SREBP 2). In addition, mRNA levels of other enzymes of interest were measured (ACAT 2, as well as HMGCoA Reductase and HMGCoA Synthase). The gene expression study was completed with SRB1 and LDLr, apolipoproteins A1 and B and membrane transporters ABC A1, ABC G5. The major effect induced by a low level of DU contamination in apo-E deficient mice was a decrease in hepatic gene expression of the enzyme CYP7B1 (-23%) and nuclear

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.)

Occupational exposure and mortality in the German uranium miner cohort; Berufliche Exposition und Mortalitaet in der deutschen Uranbergarbeiterkohorte

Energy Technology Data Exchange (ETDEWEB)

Schnelzer, M.; Dufey, F.; Grosche, B.; Sogl, M.; Tschense, A.; Walsh, L.; Kreuzer, M. [Bundesamt fuer Strahlenschutz, Neuherberg (Germany). Fachbereich Strahlenschutz und Gesundheit; Dahmann, D. [Berufsgenossenschaft Rohstoffe und chemische Industrie, Bochum (Germany). Inst. fuer Gefahrstoff-Forschung; Lehmann, F. [Berufsgenossenschaft Rohstoffe und chemische Industrie, Gera (Germany). Praeventionsbereich; Otten, H. [Deutsche Gesetzliche Unfallversicherung, Berlin (Germany)

2014-07-01

The German uranium miners cohort study comprises 58,982 men employed in the GDR by the Wismut company for at least six months between 1946 and 1989. Particularly in the early years, miners were exposed to high levels of radon, silica and other harmful substances. The aim of the cohort study is to investigate the health effects of occupational exposures. The cohort was established in 1998 with mortality follow-ups every five years, i.e. vital status and cause of death are ascertained. Annual exposures to radon progeny, external gamma-radiation, long-lived radionuclides, fine dust, silica and arsenic dust were individually assessed by means of a comprehensive job-exposure matrix. For data analyses Poisson regression models were used. By end of 2008, 25,438 (43 %) cohort members were deceased with known cause of death in 94 %. In total 7,780 cancer mortalities were observed, including 3,500 from lung cancer. Lung cancer mortality is twice as high as in the general population largely due to occupational radon progeny and silica exposure. Also 975 silicosis deaths were observed and there is some evidence for a relationship between radon progeny exposure and cancers of the extra-thoracic airways. Circulatory diseases and non-malignant diseases of the airways were also investigated, but no relationship to occupational exposure was found. Up to now health effects of uranium mining in the Wismut cohort primarily manifest themselves as increases in lung cancer and silicosis mortality due to high radon progeny and silica exposure. With increasing duration of follow-up, further findings regarding more rare causes of death and levels of exposure relevant today are expected.

Mortality analysis in the French cohort of uranium miners

International Nuclear Information System (INIS)

Vacquier, B.

2008-10-01

The objective of this thesis is to contribute to the estimation of radiation-induced risks at low dose rates. This work is based on the cohort of uranium miners French presenting multiple exposures, contamination by internal (radon and uranium dust) and external exposure (gamma radiation). An analysis of the risk of death and the relationship risk exposure was carried out within the cohort of uranium miners after extension of the monitoring until 1999, for cancers diseases and non-cancers. In addition, an analysis taking into account multiple exposures to ionizing radiation was carried out within the framework of this thesis. This analysis has improved knowledge on the risk of mortality associated with low levels of exposure to radon. (author)

Radiation effects after low dose chronic long-term exposure

International Nuclear Information System (INIS)

Fliedner, T.M.; Friesecke, I.

1997-01-01

This document approaches the radiation effects after low dose chronic long-term exposure, presenting examples occurred, the pathophysiologic mechanisms for cell system tolerance in elevated radiation fields, and the diagnostic and therapeutic possibilities

The Chemistry and Toxicology of Depleted Uranium

Directory of Open Access Journals (Sweden)

Sidney A. Katz

2014-03-01

Full Text Available Natural uranium is comprised of three radioactive isotopes: 238U, 235U, and 234U. Depleted uranium (DU is a byproduct of the processes for the enrichment of the naturally occurring 235U isotope. The world wide stock pile contains some 1½ million tons of depleted uranium. Some of it has been used to dilute weapons grade uranium (~90% 235U down to reactor grade uranium (~5% 235U, and some of it has been used for heavy tank armor and for the fabrication of armor-piercing bullets and missiles. Such weapons were used by the military in the Persian Gulf, the Balkans and elsewhere. The testing of depleted uranium weapons and their use in combat has resulted in environmental contamination and human exposure. Although the chemical and the toxicological behaviors of depleted uranium are essentially the same as those of natural uranium, the respective chemical forms and isotopic compositions in which they usually occur are different. The chemical and radiological toxicity of depleted uranium can injure biological systems. Normal functioning of the kidney, liver, lung, and heart can be adversely affected by depleted uranium intoxication. The focus of this review is on the chemical and toxicological properties of depleted and natural uranium and some of the possible consequences from long term, low dose exposure to depleted uranium in the environment.

Occupational health experience with a contractor uranium refinery

International Nuclear Information System (INIS)

Heatherton, R.C.

1975-01-01

This paper presents information related to the occupational exposure of workers in uranium refinery operations at the Feed Materials Production Center since 1958. Included are: a brief history of the FMPC; a description of the operations and the principal sources of exposure; airborne uranium, urinary excretion, in vivo monitoring and tissue analysis data; and some observations regarding the exposure and health status of employees

Use of historical uranium air sampling data to estimate worker exposure potential to airborne radioactive particulate in a uranium processing facility.

Science.gov (United States)

Methner, M M; Feng, H A; Utterback, D F

2001-12-01

Historical industrial hygiene monitoring records from a uranium processing plant were collected and analyzed to characterize exposure potential to airborne radioactive particulate. More than 2,100 samples were collected during the period of 1954-1968. The data was organized by job title, plant number, and year of measurement. Laboratory analysis of air samples indicated a wide range of potential exposures to the alpha-emitting particulate. Logarithmic transformation of the data was necessary to approximate Gaussian distributions. Geometric Mean (GM) values were used as the measure of central tendency within years. GM values ranged from 23-49 disintegrations per minute per cubic meter of air sampled (dpm/m3) with the years 1963 and 1964 being significantly higher than other years (ANOVA: p exposure potential across plants, GM ranged from 20-68 dpm/m3, with plants 5 and 8 being significantly higher than the others (ANOVA: p Exposure potential for specific job titles across the plants varied widely. GM for clerks was the lowest (11 dpm/m3) while furnace operators were the highest (235 dpm/m3). Other job titles with potentially high exposures were chemical operators, forklift operators, machine operators, and furnace operators. This analysis indicates the magnitude and distributions of worker exposure to alpha-emitting airborne particulate. Additional analysis and epidemiologic studies are planned for this facility.

X-ray photoelectron and Auger electron spectroscopic study of the adsorption of molecular iodine on uranium metal and uranium dioxide

International Nuclear Information System (INIS)

Dillard, J.G.; Moers, H.; Klewe-Nebenius, H.; Kirch, G.; Pfennig, G.; Ache, H.J.

1984-01-01

The adsorption of molecular iodine on uranium metal and on uranium dioxide has been investigated at 25 0 C. Clean surfaces were prepared in an ultrahigh vacuum apparatus and were characterized by X-ray photoelectron (XPS) and X-ray and electron-induced Auger electron spectroscopies (AES). Adsorption of I 2 was studied for exposures up to 100 langmuirs (1 langmuir = 10 -6 torr s) on uranium metal and to 75 langmuirs on uranium dioxide. Above about 2-langmuir I 2 exposure on uranium, spectroscopic evidence is obtained to indicate the beginning of UI 3 formation. Saturation coverage for I 2 adsorption on uranium dioxide occurs at approximately 10-15 langmuirs. Analysis of the XPS and AES results as well as studies of spectra as a function of temperature lead to the conclusions that a dissociative chemisorption/reaction process occurs on uranium metal while nondissociative adsorption occurs on uranium dioxide. Variations in the iodine Auger kinetic energy and in the Auger parameter are interpreted in light of extra-atomic relaxation processes. 42 references, 10 figures, 1 table

Chronic intermittent ethanol exposure in early adolescent and adult male rats: effects on tolerance, social behavior, and ethanol intake.

Science.gov (United States)

Broadwater, Margaret; Varlinskaya, Elena I; Spear, Linda P

2011-08-01

Given the prevalence of alcohol use in adolescence, it is important to understand the consequences of chronic ethanol exposure during this critical period in development. The purpose of this study was to assess possible age-related differences in susceptibility to tolerance development to ethanol-induced sedation and withdrawal-related anxiety, as well as voluntary ethanol intake after chronic exposure to relatively high doses of ethanol during adolescence or adulthood. Juvenile/adolescent and adult male Sprague-Dawley rats were assigned to one of five 10-day exposure conditions: chronic ethanol (4 g/kg every 48 hours), chronic saline (equivalent volume every 24 hours), chronic saline/acutely challenged with ethanol (4 g/kg on day 10), nonmanipulated/acutely challenged with ethanol (4 g/kg on day 10), or nonmanipulated. For assessment of tolerance development, duration of the loss of righting reflex (LORR) and blood ethanol concentrations (BECs) upon regaining of righting reflex (RORR) were tested on the first and last ethanol exposure days in the chronic ethanol group, with both saline and nonmanipulated animals likewise challenged on the last exposure day. Withdrawal-induced anxiety was indexed in a social interaction test 24 hours after the last ethanol exposure, with ethanol-naïve chronic saline and nonmanipulated animals serving as controls. Voluntary intake was assessed 48 hours after the chronic exposure period in chronic ethanol, chronic saline and nonmanipulated animals using an 8-day 2 bottle choice, limited-access ethanol intake procedure. In general, adolescent animals showed shorter durations of LORR and higher BECs upon RORR than adults on the first and last ethanol exposure days, regardless of chronic exposure condition. Adults, but not adolescents, developed chronic tolerance to the sedative effects of ethanol, tolerance that appeared to be metabolic in nature. Social deficits were observed after chronic ethanol in both adolescents and adults

Focus on Chronic Exposure for Deriving Drinking Water Guidance Underestimates Potential Risk to Infants

Directory of Open Access Journals (Sweden)

Helen Goeden

2018-03-01

Full Text Available In 2007, the Minnesota Department of Health (MDH developed new risk assessment methods for deriving human health-based water guidance (HBG that incorporated the assessment of multiple exposure durations and life stages. The methodology is based on US Environmental Protection Agency recommendations for protecting children’s health (US EPA 2002. Over the last 10 years, the MDH has derived multiple duration (e.g., short-term, subchronic, and chronic water guidance for over 60 chemicals. This effort involved derivation of multiple duration reference doses (RfDs and selection of corresponding water intake rates (e.g., infant, child, and lifetime. As expected, RfDs typically decreased with increasing exposure duration. However, the corresponding HBG frequently did not decrease with increasing duration. For more than half of the chemicals, the shorter duration HBG was lower than chronic HBG value. Conventional wisdom has been that chronic-based values will be the most conservative and will therefore be protective of less than chronic exposures. However, the MDH’s experience highlights the importance of evaluating short-term exposures. For many chemicals, elevated intake rates early in life, coupled with short-term RfDs, resulted in the lowest HBG. Drinking water criteria based on chronic assessments may not be protective of short-term exposures in highly exposed populations such as formula-fed infants.

Residual insufficiency of hematopoiesis after acute or chronic exposure to gamma radiation or neutrons

International Nuclear Information System (INIS)

Wangenheim, K.H. v.; Peterson, H.P.; Feinendegen, L.E.

1983-01-01

Recovery of the stem cell quality is possible after acute exposure to 500 rad γ radiation up to a period of 6 months. Beyond this data, a significant residual damage remains. The same applies to quantitative stem cell recovery. Chronic γ exposure leads to less radiation damage than acute exposure. After a total accumulation of 500 rad, the proliferation factors after chronic exposure were, on an average 20% higher than after acute radiation exposure. 6 MeV neutron exposure reduced the stem cell quality and stem cell count much more efficiently than γ exposure. The relative biological effect of neutrons is at least 2.5 times as high as the γ effect, both for the stem cell count and the stem cell quality. (orig.) [de

Association between pre- and perinatal exposures and Tourette syndrome or chronic tic disorder in the ALSPAC cohort.

Science.gov (United States)

Mathews, Carol A; Scharf, Jeremiah M; Miller, Laura L; Macdonald-Wallis, Corrie; Lawlor, Debbie A; Ben-Shlomo, Yoav

2014-01-01

Tourette syndrome and chronic tic disorder are heritable but aetiologically complex. Although environment plays a role in their development, existing studies of non-genetic risk factors are inconsistent. To examine the association between pre- and perinatal exposures and Tourette syndrome/chronic tic disorder in the Avon Longitudinal Study of Parents and Children (ALSPAC) prospective longitudinal pre-birth cohort. Relationships between exposures and Tourette syndrome/chronic tic disorder were examined in 6090 children using logistic regression. Maternal alcohol and cannabis use, inadequate maternal weight gain and parity were associated with Tourette syndrome or Tourette syndrome/chronic tic disorder. Other previously reported exposures, including birth weight and prenatal maternal smoking, were not associated with Tourette syndrome/chronic tic disorder. This study supports previously reported relationships between Tourette syndrome/chronic tic disorder and prenatal alcohol exposure, and identifies additional previously unexplored potential prenatal risk factors.

Challenges of ICRP 60 for uranium refining and conversion facilities

International Nuclear Information System (INIS)

Takala, J.M.

1998-01-01

Cameco Corporation operates high-grade uranium mines in northern Saskatchewan and uranium refining and conversion facilities in Ontario. The dose limits for these and all other nuclear facilities in Canada are 50 mSv per year and 4 WLM per year, which are applied separately. However, the upcoming incorporation of the recommendations in ICRP 60 into the Canadian regulations will result in several important changes. In addition to a more restrictive dose limit, the new regulations will require that all radiation exposures be combined into a single index of exposure. Meeting the new lower dose limits of 50 mSv per year and 100 mSv per 5 years will not be a major problem at Cameco facilities. However, the incorporation of long-lived radioactive dust exposures into the dose calculation will be a major challenge. This will cause the most difficulty at the uranium refining and conversion facilities where much of the process involves handling a variety of uranium compounds in the form of a dry powder. At the uranium conversion facilities the control of exposure to airborne uranium is achieved through a combination of lung counting, urinalysis, and fixed area monitors. To progress from a system of exposure control to dose estimation to individual workers will require some major changes. (author)

Uranium tailings bibliography

International Nuclear Information System (INIS)

Holoway, C.F.; Goldsmith, W.A.; Eldridge, V.M.

1975-12-01

A bibliography containing 1,212 references is presented with its focus on the general problem of reducing human exposure to the radionuclides contained in the tailings from the milling of uranium ore. The references are divided into seven broad categories: uranium tailings pile (problems and perspectives), standards and philosophy, etiology of radiation effects, internal dosimetry and metabolism, environmental transport, background sources of tailings radionuclides, and large-area decontamination

Association between pre- and perinatal exposures and Tourette syndrome or chronic tic disorder in the ALSPAC cohort†

Science.gov (United States)

Mathews, Carol A.; Scharf, Jeremiah M.; Miller, Laura L.; Macdonald-Wallis, Corrie; Lawlor, Debbie A.; Ben-Shlomo, Yoav

2014-01-01

Background Tourette syndrome and chronic tic disorder are heritable but aetiologically complex. Although environment plays a role in their development, existing studies of non-genetic risk factors are inconsistent. Aims To examine the association between pre- and perinatal exposures and Tourette syndrome/chronic tic disorder in the Avon Longitudinal Study of Parents and Children (ALSPAC) prospective longitudinal pre-birth cohort. Method Relationships between exposures and Tourette syndrome/chronic tic disorder were examined in 6090 children using logistic regression. Results Maternal alcohol and cannabis use, inadequate maternal weight gain and parity were associated with Tourette syndrome or Tourette syndrome/chronic tic disorder. Other previously reported exposures, including birth weight and prenatal maternal smoking, were not associated with Tourette syndrome/chronic tic disorder. Conclusions This study supports previously reported relationships between Tourette syndrome/chronic tic disorder and prenatal alcohol exposure, and identifies additional previously unexplored potential prenatal risk factors. PMID:24262815

Methodology for uranium compounds characterization applied to biomedical monitoring

International Nuclear Information System (INIS)

Ansoborlo, E.; Chalabreysse, J.; Henge-Napoli, M.H.; Pujol, E.

1991-01-01

Chronic exposure and accidental contamination to uranium compounds in the nuclear industry, led the authors to develop a methodology in order to characterize those compounds applied to biomedical monitoring. Such a methodology, based on the recommendation of the ICRP and the assessment of Annual Limit on Intake (ALI) values, involves two main steps: (1) The characterization of the industrial compound, i.e. its physico-chemical properties like density (g cm -3 ), specific area (m 2 g -1 ), x-ray spectrum (crystalline form), solid infrared spectrum (wavelength and bounds), mass spectrometry (isotopic composition), and particle size distribution including measurement of the Activity Median Aerodynamic Diameter (AMAD). They'll specially study aging and hydration state of some compounds. (2) The study of in vitro solubility in several biochemical medium like bicarbonates, Basal Medium Eagle (BME) used in cellular culture, Gamble solvent, which is a serum simulant, with oxygen bubbling, and Gamble added with superoxide anions O2 - . Those different mediums allow one to understand the dissolution mechanisms (oxidation, chelating effects...) and to give ICRP classification D, W, or Y. Those two steps are essential to assess a biomedical monitoring either in routine or accidental exposure, and to calculate the ALI. Results on UO3, UF4 and U02 in the French uranium industry are given

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.

Investigation of uranium binding forms in environmentally relevant waters and bio-fluids

International Nuclear Information System (INIS)

Osman, Alfatih Ahmed Alamin

2014-01-01

Uranium from natural and anthropogenic sources is continuously and increasingly released into the environment, enters the food chain, and eventually accumulates into the bio-systems including humans. Therefore, uranium exposure to human becomes more and more a subject of interest in many scientific disciplines such as environmental medicine, toxicology, and radiation protection. Ingestion of uranium via food and drinking water is one of the important pathways of exposure. The ongoing discussion in Germany and the European Union (EU) on the maximum uranium levels in drinking water reflects the increasing awareness of uranium as a public health problem. For water suppliers in many countries around the world, uranium contamination of drinking water also becomes a salient issue. Nevertheless, the health consequences are dependent not only on the level and duration of exposure, but mainly on the physical and chemical forms of uranium (speciation). Unlike total concentration, speciation can provide more information on uranium behavior (mobility, bioavailability, and toxicity) in both geo-systems and bio-systems. The aim of the current work is to elucidate uranium speciation in natural samples (water, bio-fluids) by both spectroscopic means and theoretical modeling. For this purpose, environmentally relevant waters (mineral water, groundwater, acid drainage waters) and natural human body fluids have been investigated. The cryogenic time-resolved laser-induced fluorescence spectroscopy (cryo-TRLFS) at 153 K has successfully been used to identify the speciation in such complex matrices of high organic content and low uranium concentrations without any prior treatment. Data about uranium binding forms in natural waters could be used for more insight research on uranium chemo-toxicity in drinking water since there is no available information on the long-term exposure of low uranium concentrations via ingestion on humans. Altogether the obtained data provides a comprehensive

Investigation of uranium binding forms in environmentally relevant waters and bio-fluids

Energy Technology Data Exchange (ETDEWEB)

Osman, Alfatih Ahmed Alamin

2014-06-04

Uranium from natural and anthropogenic sources is continuously and increasingly released into the environment, enters the food chain, and eventually accumulates into the bio-systems including humans. Therefore, uranium exposure to human becomes more and more a subject of interest in many scientific disciplines such as environmental medicine, toxicology, and radiation protection. Ingestion of uranium via food and drinking water is one of the important pathways of exposure. The ongoing discussion in Germany and the European Union (EU) on the maximum uranium levels in drinking water reflects the increasing awareness of uranium as a public health problem. For water suppliers in many countries around the world, uranium contamination of drinking water also becomes a salient issue. Nevertheless, the health consequences are dependent not only on the level and duration of exposure, but mainly on the physical and chemical forms of uranium (speciation). Unlike total concentration, speciation can provide more information on uranium behavior (mobility, bioavailability, and toxicity) in both geo-systems and bio-systems. The aim of the current work is to elucidate uranium speciation in natural samples (water, bio-fluids) by both spectroscopic means and theoretical modeling. For this purpose, environmentally relevant waters (mineral water, groundwater, acid drainage waters) and natural human body fluids have been investigated. The cryogenic time-resolved laser-induced fluorescence spectroscopy (cryo-TRLFS) at 153 K has successfully been used to identify the speciation in such complex matrices of high organic content and low uranium concentrations without any prior treatment. Data about uranium binding forms in natural waters could be used for more insight research on uranium chemo-toxicity in drinking water since there is no available information on the long-term exposure of low uranium concentrations via ingestion on humans. Altogether the obtained data provides a comprehensive

Chronic obstructive pulmonary disease and long-term exposure to traffic-related air pollution: a cohort study

DEFF Research Database (Denmark)

Andersen, Zorana J; Hvidberg, Martin; Jensen, Steen S

2011-01-01

Short-term exposure to air pollution has been associated with exacerbation of chronic obstructive pulmonary disease (COPD), whereas the role of long-term exposures on the development of COPD is not yet fully understood.......Short-term exposure to air pollution has been associated with exacerbation of chronic obstructive pulmonary disease (COPD), whereas the role of long-term exposures on the development of COPD is not yet fully understood....

Effects of prenatal exposure to chronic mild stress and toluene in rats

DEFF Research Database (Denmark)

Hougaard, Karin; Andersen, Maibritt B; Hansen, Ase M

2005-01-01

The aim of the present study was to elucidate whether prenatal chronic stress, in combination with exposure to a developmental neurotoxicant, would increase effects in the offspring compared with the effects of either exposure alone. Development and neurobehavioral effects were investigated...... in female offspring of pregnant rats (Mol:WIST) exposed to chronic mild stress (CMS) during gestational days (GD) 9-20, or 1500 ppm toluene, 6 h/day during gestational days 7-20, or a combination of the two. Prenatal CMS was associated with decreased thymic weight and increased auditory startle response....... The corticosterone response to restraint seemed modified by prenatal exposure to toluene. Lactational body weight was decreased in offsprings subjected to CMS, primarily due to effects in the combined exposure group. Cognitive function was investigated in the Morris water maze, and some indications of improved...

Carcinogenesis of inhaled radio daughters with uranium ore dust in beagle dogs

International Nuclear Information System (INIS)

Filipy, R.E.; Dagle, G.E.; Palmer, R.F.; Stuart, B.O.

1977-01-01

Daily exposures of adult beagle dogs to inhaled radon daughters and to uranium ore dust for 4-1/2 to 6 yr have produced respiratory tract carcinomas, at similar cumulative working level months (WLM) of exposures to those which induced carcinomas in uranium miners. Biological data from the beagle-dog experiments can therefore be used for prediction of carcinogenic risk under changing exposure conditions in future uranium miners

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

International Nuclear Information System (INIS)

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

1978-07-01

Spatial variability in sampling for soil uranium distribution by a polar coordinate system was evaluated in randomly selected soil cores at the Los Alamos Scientific Laboratory. Variations for surface (0- to 2.5-cm-deep) soils were 0.18 at 10 m from the nuclear weapons test detonation point and 0.96 at 50 m. Results were strongly influenced by past uranium dispersal patterns, variable leaching of uranium debris, and surface water runoff. A total surface (0- to 5-cm) soil uranium inventory within a 12.6-ha circle centered on the E-F detonation point was estimated to be 3000 kg when calculated by soil uranium concentration isopleths and 4500 kg when using annuli of a polar coordinate sampling system. Uranium concentrations in tissues of deer mice (Peromyscus maniculatus) and pocket gophers (Thomomys bottae) were sufficiently different to conclude that the greater bioavailability of uranium in the top few millimeters of soil at E-F Site, combined with the difference in grooming and food habits of the animals, resulted in greater contamination of deer mice than of pocket gophers

Uranium XAFS analysis of kidney from rats exposed to uranium.

Science.gov (United States)

Kitahara, Keisuke; Numako, Chiya; Terada, Yasuko; Nitta, Kiyohumi; Shimada, Yoshiya; Homma-Takeda, Shino

2017-03-01

The kidney is the critical target of uranium exposure because uranium accumulates in the proximal tubules and causes tubular damage, but the chemical nature of uranium in kidney, such as its chemical status in the toxic target site, is poorly understood. Micro-X-ray absorption fine-structure (µXAFS) analysis was used to examine renal thin sections of rats exposed to uranyl acetate. The U L III -edge X-ray absorption near-edge structure spectra of bulk renal specimens obtained at various toxicological phases were similar to that of uranyl acetate: their edge position did not shift compared with that of uranyl acetate (17.175 keV) although the peak widths for some kidney specimens were slightly narrowed. µXAFS measurements of spots of concentrated uranium in the micro-regions of the proximal tubules showed that the edge jump slightly shifted to lower energy. The results suggest that most uranium accumulated in kidney was uranium (VI) but a portion might have been biotransformed in rats exposed to uranyl acetate.

Ocular effects of chronic exposure to welding light on calabar welders

African Journals Online (AJOL)

It was generally observed that welders in Calabar, Nigeria did not always wear their protective goggles during welding. Since chronic exposure to welding light can impair vision this study was done to assess the effect of exposure to welding light on ocular function of welders in Calabar, Nigeria. There were 195 subjects ...

Guide to the bioassay of uranium at uranium mine-mill facilities

International Nuclear Information System (INIS)

1981-01-01

As a result of occupational exposure, uranium may be taken into the body by inhalation, ingestion or absorption through skin wounds. The organs at risk are the lung, kidney, and bones. Analysis of urine samples for uranium is recommended on a regular monthly basis, before and after a rest period, and it is suggested that a worker be removed from a working area if a level above 300 μg/l is found before a rest period, or 150 μg/l after a rest period. Background information on the development of a bioassay program is given, and a recommended program for uranium mine and mill facilities is included. (L.L.)

Occupational diseases in uranium and ore miners, related to the radiation exposure in Czech Republic, in 2003-2013

International Nuclear Information System (INIS)

Mueller, T.

2014-01-01

Dozens cases of disease of former or present uranium and ore miners are submitted to judgment as occupational diseases every year in the Czech Republic. Patients or attending physicians suggest that these cases are caused by occupational ionizing radiation. Only a part of these cases is qualified as occupational disease. The term 'occupational disease' is rather juridical term which underlies the right to financial compensation. The causal association with exposure to ionizing radiation cannot be indisputably verified by expert medical opinion. Most diseases in uranium and ore miners, which are proposed as occupational disease, are malignant tumors. The majority of judged cases are lung cancers from radioactive agents. The lecture gives general information about all judged cases of occupational diseases in former uranium and ore miners in the Czech Republic in the years 2002 - 2013. In the period 2002-13 were 40-80 cases submitted to judgment as potential occupational disease every year. (authors)

The neurotoxicology of uranium

International Nuclear Information System (INIS)

Dinocourt, Céline; Legrand, Marie; Dublineau, Isabelle; Lestaevel, Philippe

2015-01-01

The brain is a target of environmental toxic pollutants that impair cerebral functions. Uranium is present in the environment as a result of natural deposits and release by human applications. The first part of this review describes the passage of uranium into the brain, and its effects on neurological functions and cognitive abilities. Very few human studies have looked at its cognitive effects. Experimental studies show that after exposure, uranium can reach the brain and lead to neurobehavioral impairments, including increased locomotor activity, perturbation of the sleep-wake cycle, decreased memory, and increased anxiety. The mechanisms underlying these neurobehavioral disturbances are not clearly understood. It is evident that there must be more than one toxic mechanism and that it might include different targets in the brain. In the second part, we therefore review the principal mechanisms that have been investigated in experimental models: imbalance of the anti/pro-oxidant system and neurochemical and neurophysiological pathways. Uranium effects are clearly specific according to brain area, dose, and time. Nonetheless, this review demonstrates the paucity of data about its effects on developmental processes and the need for more attention to the consequences of exposure during development.

Effects of prenatal exposure to chronic mild stress and toluene in rats

DEFF Research Database (Denmark)

Hougaard, K. S.; Andersen, Maud Bering; Hansen, A. M.

2005-01-01

The aim of the present study was to elucidate whether prenatal chronic stress, in combination with exposure to a developmental neurotoxicant, would increase effects in the offspring compared with the effects of either exposure alone. Development and neurobehavioral effects were investigated in fe...

Pesticide exposures and chronic kidney disease of unknown etiology: an epidemiologic review.

Science.gov (United States)

Valcke, Mathieu; Levasseur, Marie-Eve; Soares da Silva, Agnes; Wesseling, Catharina

2017-05-23

The main causes of chronic kidney disease (CKD) globally are diabetes and hypertension but epidemics of chronic kidney disease of unknown etiology (CKDu) occur in Central America, Sri Lanka, India and beyond. Althoug also being observed in women, CKDu concentrates among men in agricultural sectors. Therefore, suspicions fell initially on pesticide exposure, but currently chronic heat stress and dehydration are considered key etiologic factors. Responding to persistent community and scientific concerns about the role of pesticides, we performed a systematic review of epidemiologic studies that addressed associations between any indicator of pesticide exposure and any outcome measure of CKD. Of the 21 analytical studies we identified, seven were categorized as with low, ten with medium and four with relatively high explanation value. Thirteen (62%) studies reported one or more positive associations, but four had a low explanation value and three presented equivocal results. The main limitations of both positive and negative studies were unspecific and unquantified exposure measurement ('pesticides'), the cross-sectional nature of most studies, confounding and selection bias. The four studies with stronger designs and better exposure assessment (from Sri Lanka, India and USA) all showed exposure-responses or clear associations, but for different pesticides in each study, and three of these studies were conducted in areas without CKDu epidemics. No study investigated interactions between pesticides and other concommittant exposures in agricultural occupations, in particular heat stress and dehydration. In conclusion, existing studies provide scarce evidence for an association between pesticides and regional CKDu epidemics but, given the poor pesticide exposure assessment in the majority, a role of nephrotoxic agrochemicals cannot be conclusively discarded. Future research should procure assessment of lifetime exposures to relevant specific pesticides and enough power

The use of uranium isotopes and the U/Th ratio to evaluate the fingerprint of plants following uranium releases from fuel cycle settlements

International Nuclear Information System (INIS)

Pourcelot, L.; Boulet, B.; Cariou, N.

2015-01-01

This paper uses data from the environmental monitoring of fuel cycle settlements. It aims to evaluate uranium released into the terrestrial environment. Measurement of uranium isotopes in terrestrial plants allows illustrating the consequences of chronic and incidental releases of depleted uranium into the atmosphere. However, such an analytical approach reaches its limits when natural uranium is released. Indeed, distinguishing natural uranium from releases and uranium from the radiological background is difficult. For this reason, we propose normalizing uranium activity measured in plants taken in the surroundings of nuclear sites with respect to 232 Th, considering that the source of this latter is the background. (authors)

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)

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)

Uranium industry vs radioecological risk

International Nuclear Information System (INIS)

Jonchev, L.

1998-01-01

Uranium industry development on a worldwide scale accounts for a technological increase in the natural radiation background as a result of human activity. The higher radionuclide concentration leads to an increase of the radiological risk which is a basic criterion for environmental and human protection. Therefore its determination with regard to the uranium industry and particularly to the process of its closure is mandatory. Restoration and control of the environment is closely linked to a system of criteria and levels for assessment of the radionuclide contamination hazards. Annual individual effective dose of 2.3 mSv is accepted as anormal average level for radiation exposure of the Bulgarian population from the natural radiation background. The value of 3.5 mSv/y is accepted as the uppermost limit of the normal background exposure level. According to ICRP recommendations the additional overbackground exposure of the population should not exceed 1.0 mSv/y towards the background level for the region. This holds true also for areas neighbouring to the uranium mining sites

Fetal contamination with cadmium following chronic exposure of rat ...

African Journals Online (AJOL)

Fetal contamination with cadmium following chronic exposure of rat dams during gestation. ... African Journal of Applied Zoology and Environmental Biology ... It was concluded that cadmium, contrary to previous reports, can pass through the placenta in appreciable quantity to contaminate the fetus to possibly cause fetal ...

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

Impact of a chronic ingestion of radionuclides on cholesterol metabolism in the rat: example of depleted uranium and cesium 137

International Nuclear Information System (INIS)

Racine, Radjini

2009-01-01

Depleted uranium (DU) and cesium-137 ( 137 Cs) are radionuclides spread in the environment due to industrial activities, incidents or accidents. This pollution sets a risk of human exposure to low levels of radiations through contaminated foodstuff. The impact of a chronic ingestion of DU or 137 Cs on cholesterol metabolism in the liver and the brain has been studied. Indeed, cholesterol is crucial in physiology, being a component of cell membranes and a precursor to numerous molecules (bile acids...). Disruption of its metabolism is associated to many pathologies such as atherosclerosis or Alzheimer disease. Rats daily ingested a low level of DU or 137 Cs over 9 months. For each radionuclide, a reference model (rats contaminated since adulthood) and a more sensitive model (hypercholesterolemic or contaminated since fetal life) were studied. The effects mainly consist of changes in gene expression or enzymatic activity of various actors of cholesterol metabolism. DU mainly affects one catabolism enzyme in both models, as well as membrane transporters and regulation factors. 137 Cs mainly affects the storage enzyme in both models as well as catabolism enzymes, apolipoproteins, and regulation factors. No change in the plasma profile or in the tissue concentration of cholesterol (hepatic/cerebral) is recorded, whatever the model and the radionuclide. Thus, a chronic internal contamination with DU or 137 Cs induces molecular modifications in cholesterol metabolism in the rat, without affecting its homeostasis or the general health status in all of our experimental models. (author)

Occupational diseases in uranium and ore miners related to radiation exposure in the Czech Republic in 2002 - 2007

International Nuclear Information System (INIS)

Mueller, T.

2008-01-01

Dozens cases of disease of former or present uranium and ore miners are submitted to judgment as occupational diseases every year in the Czech Republic. Patients or attending physicians suggest that these cases are caused by occupational ionizing radiation. Only a part of these cases is qualified as occupational disease, nevertheless they can cause many juridical problems. The term 'occupational disease' is rather juridical term which underlies the right to financial compensation. The causal association with exposure to ionizing radiation cannot be indisputably verified by expert medical opinion. Most diseases in uranium and ore miners, which are proposed as occupational disease, are malignant tumors. The majority of judged cases are lung cancers from radioactive agents. The poster gives general information about all judged cases of occupational diseases in former uranium and ore miners in the Czech Republic in the years 2002 -2007. It also provides short information about standards of professional radiation exposure assessment valid in the other countries. Most frequent diseases were lung cancers. Nevertheless the rate of lung cancers acknowledged as occupational disease decreases during the last two decades. Non-melanoma skin cancers are on the second place. The rate of skin cancers increases. We can explain this fact by better diagnostics and by new method which allows more precious assessment of the skin dose. The method is used since 2005. Leukemias are on the third place (1-2 cases in the year). (authors)

Occupational diseases in uranium and ore miners related to radiation exposure in the Czech Republic in 2002 - 2007

International Nuclear Information System (INIS)

Mueller, T.

2009-01-01

Dozens cases of disease of former or present uranium and ore miners are submitted to judgment as occupational diseases every year in the Czech Republic. Patients or attending physicians suggest that these cases are caused by occupational ionizing radiation. Only a part of these cases is qualified as occupational disease, nevertheless they can cause many juridical problems. The term 'occupational disease' is rather juridical term which underlies the right to financial compensation. The causal association with exposure to ionizing radiation cannot be indisputably verified by expert medical opinion. Most diseases in uranium and ore miners, which are proposed as occupational disease, are malignant tumors. The majority of judged cases are lung cancers from radioactive agents. The poster gives general information about all judged cases of occupational diseases in former uranium and ore miners in the Czech Republic in the years 2002-2007. It also provides short information about standards of professional radiation exposure assessment valid in the other countries. Most frequent diseases were lung cancers. Nevertheless the rate of lung cancers acknowledged as occupational disease decreases during the last two decades. Non-melanoma skin cancers are on the second place. The rate of skin cancers increases. We can explain this fact by better diagnostics and by new method which allows more precious assessment of the skin dose. The method is used since 2005. Leukemias are on the third place (1-2 cases in the year). (authors)

Protein expression of saccharomyces cerevisiae in response to uranium exposure

International Nuclear Information System (INIS)

Sakamoto, Fuminori; Nankawa, Takuya; Kozai, Naofumi; Ohnuki, Toshihiko; Fujii, Tsutomu; Iefuji, Haruyuki; Francis, A.J.

2007-01-01

Protein expression of Saccharomyces cerevisiae grown in the medium containing 238 U (VI) and 233 U (VI) was examined by two-dimensional gel electrophoresis. Saccharomyces cerevisiae of BY4743 was grown in yeast nitrogen base medium containing glucose and glycerol 2-phosphate and 238 U of 0, 2.0, and 5.0 x 10 -4 M or 233 U of 2.5 x 10 -6 M (radioactivity was higher by 350 times than 2.0 x 10 -4 M 238 U) and 5.0 x 10 -6 M for 112 h at 30 degC. The growth of Saccharomyces cerevisiae was monitored by measuring OD 600 at 112 h after the inoculation. Uranium concentrations in the media also were measured by radiometry using a liquid scintillation counter. The growths of the yeast grown in the above media were in the following order: control>2.5 x 10 -6 M 233 U>2.0 x 10 -4 M 238 U>5.0 x 10 -6 M 233 U>5.0 x 10 -4 M 238 U. This result indicated that not only radiological but also chemical effect of U reduced the growth of the yeast. The concentrations of U in the medium containing 238 U or 233 U decreased, suggesting U accumulation by the yeast cells. The 2-D gel electrophoresis analysis showed the appearance of several spots after exposure to 238 U or to 233 U but not in the control containing no uranium. These results show that the yeast cells exposed to U express several specific proteins. (author)

Occupational exposure during remediation works at a uranium tailings pile.

Science.gov (United States)

Dinis, Maria de Lurdes; Fiúza, António

2013-05-01

The aim of this study was to assess by different approaches the occupational exposure during the remediation of a tailings dam in an abandoned uranium mining site, with an area of about 13.3 ha and an estimated volume of 1.39 million m³. A hypothetical scenario was created in which the workers involved in the remediation activities were exposed to radiation through both internal and external pathways. It was intended to assess quantitatively the potential exposure of the workforce involved in the remediation works, focussing particularly on the inhalation of radon and on the gamma irradiation from the contaminated soil. Different methodologies were considered based on a deterministic and a probabilistic approach for dose assessment and risk assessment, respectively. The deterministic approach typically employs a highly "conservative" single value for each input parameter. The probabilistic approach employs sensitivity and uncertainty analysis of input parameters using probabilistic distributions of the sensitive parameters. The results indicate that annual effective dose limit for occupational exposure (worst scenario case created) may reach a significant fraction of occupational radiation protection limits. This is also stressed by the values obtained for the occupational risk estimated by Monte Carlo methodology using probabilistic distributions for the input parameters. The results also showed that the pathway with the highest dose does not necessarily correspond to the pathway with the highest risk. Nevertheless, it is well known that probabilistic analysis generally produces more realistic results. Copyright © 2012 Elsevier Ltd. All rights reserved.

Ultraviolet-B radiation mobilizes uranium from uranium-dissolved organic carbon complexes in aquatic systems, demonstrated by asymmetrical flow field-flow fractionation.

Science.gov (United States)

Nehete, Sachin Vilas; Christensen, Terje; Salbu, Brit; Teien, Hans-Christian

2017-05-05

Humic substances have a tendency to form complexes with metal ions in aquatic medium, impacting the metal mobility, decreasing bioavailability and toxicity. Ultraviolet-B (UV-B) radiation exposure degrades the humic substance, changes their molecular weight distribution and their metal binding capacity in aquatic medium. In this study, we experimented the effect of UV-B radiation on the uranium complexed with fulvic acids and humic acids in a soft water system at different pH, uranium concentrations and radiant exposure. The concentration and distribution of uranium in a complexed form were investigated by asymmetrical flow field-flow fractionation coupled to multi detection technique (AsFlFFF-UV-ICP-MS). The major concentration of uranium present in complexes was primarily associated with average and higher molecular weight fulvic and humic acids components. The concentration of uranium in a complexed form increased with increasing fulvic and humic acid concentrations as well as pH of the solution. The higher molecular weight fraction of uranium was degraded due to the UV-B exposure, transforming about 50% of the uranium-dissolved organic carbon complexes into low molecular weight uranium species in complex form with organic ligands and/or free form. The result also suggests AsFlFFF-UV-ICP-MS to be an important separation and detection technique for understanding the interaction of radionuclides with dissolved organic matter, tracking size distribution changes during degradation of organic complexes for understanding mobility, bioavailability and ecosystem transfer of radionuclides as well as metals. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of chronic exposure to clothianidin on the earthworm Lumbricus terrestris.

Science.gov (United States)

Basley, Kate; Goulson, Dave

2017-01-01

Although neonicotinoids are targeted at insects, their predominant use as a seed dressing and their long persistence in soils mean that non-target soil organisms such as earthworms are likely to be chronically exposed to them. Chronic exposure may pose risks that are not evaluated in most toxicity tests. We experimentally tested the effect of field-realistic concentrations of a commonly used neonicotinoid, clothianidin, on mortality, weight gain, and food consumption to assess the impacts of chronic exposure over four months on fitness of L. terrestris individuals. We undertook three separate experiments, each with different exposure routes: treated soil only (experiment A), treated food and soil combined (experiment B) and treated food only (experiment C). Mortality was negatively affected by exposure from treated soil only with greatest mortality observed in the groups exposed to the two highest concentrations (20 ppb and 100 ppb), but no clear effect on mortality was found in the other two experiments. When clothianidin was present in the food, an anti-feedant effect was present in months one and two which subsequently disappeared; if this occurs in the field, it could result in reduced rates of decomposition of treated crop foliage. We found no significant effects of any treatment on worm body mass. We cannot rule out stronger adverse effects if worms come into close proximity to treated seeds, or if other aspects of fitness were examined. Overall, our data suggest that field-realistic exposure to clothianidin has a significant but temporary effect on food consumption and can have weak but significant impacts on mortality of L. terrestris.

Effects of chronic exposure to clothianidin on the earthworm Lumbricus terrestris

Directory of Open Access Journals (Sweden)

Kate Basley

2017-04-01

Full Text Available Although neonicotinoids are targeted at insects, their predominant use as a seed dressing and their long persistence in soils mean that non-target soil organisms such as earthworms are likely to be chronically exposed to them. Chronic exposure may pose risks that are not evaluated in most toxicity tests. We experimentally tested the effect of field-realistic concentrations of a commonly used neonicotinoid, clothianidin, on mortality, weight gain, and food consumption to assess the impacts of chronic exposure over four months on fitness of L. terrestris individuals. We undertook three separate experiments, each with different exposure routes: treated soil only (experiment A, treated food and soil combined (experiment B and treated food only (experiment C. Mortality was negatively affected by exposure from treated soil only with greatest mortality observed in the groups exposed to the two highest concentrations (20 ppb and 100 ppb, but no clear effect on mortality was found in the other two experiments. When clothianidin was present in the food, an anti-feedant effect was present in months one and two which subsequently disappeared; if this occurs in the field, it could result in reduced rates of decomposition of treated crop foliage. We found no significant effects of any treatment on worm body mass. We cannot rule out stronger adverse effects if worms come into close proximity to treated seeds, or if other aspects of fitness were examined. Overall, our data suggest that field-realistic exposure to clothianidin has a significant but temporary effect on food consumption and can have weak but significant impacts on mortality of L. terrestris.

Diffuse parenchymal lung disease in a case of chronic arsenic exposure

Directory of Open Access Journals (Sweden)

Somnath Bhattacharya

2016-01-01

Full Text Available A 42-year-old housewife, the resident of rural part of West Bengal, presented with gradually progressive exertional dyspnea associated with a dry cough for last 3 years clinical features were suggestive of diffuse parenchymal lung disease (DPLD. Her chest X-ray posteroanterior view and high resolution computed tomography scan of the thorax showed bilateral patchy ground glass opacities and reticulonodular pattern. Search for the etiology revealed classical skin findings of chronic arsenic exposure in the form of generalized darkening and thickening of skin and keratotic lesions over the palms and soles and classical raindrop pigmentation over leg which was present for last 7 years subsequently her bronchoalveolar lavage fluid, hair, nail, and drinking water showed significant amount of arsenic contamination. By exclusion of all known causes of DPLD, we concluded that it was a case of DPLD due to chronic arsenic exposure. To the best of our knowledge, only few case report of DPLD in chronic arsenicosis has been reported till date.

Novel Pharmacological Approaches for Treatment of Neurotoxicity Induced by Chronic Exposure to Depleted Uranium

National Research Council Canada - National Science Library

Lasley, Stephen M

2008-01-01

.... This hypothesis is consistent with previous observations ensuing from chronic intramuscular DU pellet implants in rats, and is based on the anticipation that specific pharmacological agents will...

Chronic marijuana smoke exposure in the rhesus monkey. IV: Neurochemical effects and comparison to acute and chronic exposure to delta-9-tetrahydrocannabinol (THC) in rats.

Science.gov (United States)

Ali, S F; Newport, G D; Scallet, A C; Paule, M G; Bailey, J R; Slikker, W

1991-11-01

THC is the major psychoactive constituent of marijuana and is known to produce psychopharmacological effects in humans. These studies were designed to determine whether acute or chronic exposure to marijuana smoke or THC produces in vitro or in vivo neurochemical alterations in rat or monkey brain. For the in vitro study, THC was added (1-100 nM) to membranes prepared from different regions of the rat brain and muscarinic cholinergic (MCh) receptor binding was measured. For the acute in vivo study, rats were injected IP with vehicle, 1, 3, 10, or 30 mg THC/kg and sacrificed 2 h later. For the chronic study, rats were gavaged with vehicle or 10 or 20 mg THC/kg daily, 5 days/week for 90 days and sacrificed either 24 h or 2 months later. Rhesus monkeys were exposed to the smoke of a single 2.6% THC cigarette once a day, 2 or 7 days a week for 1 year. Approximately 7 months after the last exposure, animals were sacrificed by overdose with pentobarbital for neurochemical analyses. In vitro exposure to THC produced a dose-dependent inhibition of MCh receptor binding in several brain areas. This inhibition of MCh receptor binding, however, was also observed with two other nonpsychoactive derivatives of marijuana, cannabidiol and cannabinol. In the rat in vivo study, we found no significant changes in MCh or other neurotransmitter receptor binding in hippocampus, frontal cortex or caudate nucleus after acute or chronic exposure to THC. In the monkey brain, we found no alterations in the concentration of neurotransmitters in caudate nucleus, frontal cortex, hypothalamus or brain stem.(ABSTRACT TRUNCATED AT 250 WORDS)

Elevated Arsenic and Uranium Concentrations in Unregulated Water Sources on the Navajo Nation, USA.

Science.gov (United States)

Hoover, Joseph; Gonzales, Melissa; Shuey, Chris; Barney, Yolanda; Lewis, Johnnye

2017-01-01

Regional water pollution and use of unregulated water sources can be an important mixed metals exposure pathway for rural populations located in areas with limited water infrastructure and an extensive mining history. Using censored data analysis and mapping techniques we analyzed the joint geospatial distribution of arsenic and uranium in unregulated water sources throughout the Navajo Nation, where over 500 abandoned uranium mine sites are located in the rural southwestern United States. Results indicated that arsenic and uranium concentrations exceeded national drinking water standards in 15.1 % (arsenic) and 12.8 % (uranium) of tested water sources. Unregulated sources in close proximity (i.e., within 6 km) to abandoned uranium mines yielded significantly higher concentrations of arsenic or uranium than more distant sources. The demonstrated regional trends for potential co-exposure to these chemicals have implications for public policy and future research. Specifically, to generate solutions that reduce human exposure to water pollution from unregulated sources in rural areas, the potential for co-exposure to arsenic and uranium requires expanded documentation and examination. Recommendations for prioritizing policy and research decisions related to the documentation of existing health exposures and risk reduction strategies are also provided.

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.

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

DNA methylation and histone deacetylation regulating insulin sensitivity due to chronic cold exposure.

Science.gov (United States)

Wang, Xiaoqing; Wang, Lai; Sun, Yizheng; Li, Ruiping; Deng, Jinbo; Deng, Jiexin

2017-02-01

In this study, we investigated the causal relationship between chronic cold exposure and insulin resistance and the mechanisms of how DNA methylation and histone deacetylation regulate cold-reduced insulin resistance. 46 adult male mice from postnatal day 90-180 were randomly assigned to control group and cold-exposure group. Mice in cold-exposure group were placed at temperature from -1 to 4 °C for 30 days to mimic chronic cold environment. Then, fasting blood glucose, blood insulin level and insulin resistance index were measured with enzymatic methods. Immunofluorescent labeling was carried out to visualize the insulin receptor substrate 2 (IRS2), Obese receptor (Ob-R, a leptin receptor), voltage-dependent anion channel protein 1 (VDAC1), cytochrome C (cytC), 5-methylcytosine (5-mC) positive cells in hippocampal CA1 area. Furthermore, the expressions of some proteins mentioned above were detected with Western blot. The results showed: ① Chronic cold exposure could reduce the insulin resistance index (P cold-exposure group than in control group with both immunohistochemical staining and Western blot (P cold exposure increased DNA methylation and histone deacetylation in the pyramidal cells of CA1 area and led to an increase in the expression of histone deacetylase 1 (HDAC1) and DNA methylation relative enzymes (P cold exposure can improve insulin sensitivity, with the involvement of DNA methylation, histone deacetylation and the regulation of mitochondrial energy metabolism. These epigenetic modifications probably form the basic mechanism of cold-reduced insulin resistance. Copyright © 2016 Elsevier Inc. All rights reserved.

Absorption, accumulation and biological effects of depleted uranium in Peyer's patches of rats

International Nuclear Information System (INIS)

Dublineau, I.; Grison, S.; Grandcolas, L.; Baudelin, C.; Tessier, C.; Suhard, D.; Frelon, S.; Cossonnet, C.; Claraz, M.; Ritt, J.; Paquet, P.; Voisin, P.; Gourmelon, P.

2006-01-01

The digestive tract is the entry route for radionuclides following the ingestion of contaminated food and/or water wells. It was recently characterized that the small intestine was the main area of uranium absorption throughout the gastrointestinal tract. This study was designed to determine the role played by the Peyer's patches in the intestinal absorption of uranium, as well as the possible accumulation of this radionuclide in lymphoid follicles and the toxicological or pathological consequences on the Peyer's patch function subsequent to the passage and/or accumulation of uranium. Results of experiments performed in Ussing chambers indicate that the apparent permeability to uranium in the intestine was higher (10-fold) in the mucosa than in Peyer's patches ((6.21 ± 1.21 to 0.55 ± 0.35) x 10 -6 cm/s, respectively), demonstrating that the small intestinal epithelium was the preferential pathway for the transmucosal passage of uranium. A quantitative analysis of uranium by ICP-MS following chronic contamination with depleted uranium during 3 or 9 months showed a preferential accumulation of uranium in Peyer's patches (1355% and 1266%, respectively, at 3 and 9 months) as compared with epithelium (890% and 747%, respectively, at 3 and 9 months). Uranium was also detected in the mesenteric lymph nodes (∼5-fold after contamination with DU). The biological effects of this accumulation of depleted uranium after chronic contamination were investigated in Peyer's patches. There was no induction of the apoptosis pathway after chronic DU contamination in Peyer's patches. The results indicate no change in the cytokine expression (Il-10, TGF-β, IFN-γ, TNF-α, MCP-1) in Peyer's patches and in mesenteric lymph nodes, and no modification in the uptake of yeast cells by Peyer's patches. In conclusion, this study shows that the Peyer's patches were a site of retention for uranium following the chronic ingestion of this radionuclide, without any biological consequences of

Identification of a threshold for biomass exposure index for chronic bronchitis in rural women of Mysore district, Karnataka, India

Directory of Open Access Journals (Sweden)

P A Mahesh

2013-01-01

Full Text Available Background & objectives: Exposure to air pollution due to combustion of biomass fuels remains one of the significant risk factors for chronic respiratory diseases such as chronic bronchitis. There is a need to identify the minimum threshold level of biomass index that is significantly associated with chronic bronchitis. This study was undertaken to identify a threshold for biomass exposure index in a rural women population in Mysore district, south India. Methods: A cross-sectional survey was conducted in a representative population of Mysore and Nanjangud taluks. Eight villages each from Mysore and Nanjangud were randomly selected based on the list of villages from census 2001. A house-to-house survey was carried out by trained field workers using the Burden of Obstructive Diseases questionnaire, which evaluated the biomass smoke exposure and chronic bronchitis. All the women aged above 30 yr were included in the study. Results: A total of 2011 women from Mysore and 1942 women from Nanjangud participated in the study. All women were non-smoking and used biomass fuels as the primary fuel for cooking. A threshold of biomass fuel exposure of 60 was identified on multivariate analysis in Mysore district after adjusting for age, passive smoking and working in a occupational exposure to dust, as the minimum required for a significant association with chronic bronchitis. One in every 20 women in Mysore district exposed to biomass fuel exposure index of 110 or more developed chronic bronchitis. Interpretation & conclusions: The minimum threshold of biomass exposure index of 60 is necessary to have a significant risk of developing chronic bronchitis in women. The number needed to harm to develop chronic bronchitis reduces with increasing biomass exposure index and women residing in rural Nanjangud have a higher risk for developing chronic bronchitis as compared to women in Mysore.

Identification of a threshold for biomass exposure index for chronic bronchitis in rural women of Mysore district, Karnataka, India.

Science.gov (United States)

Mahesh, P A; Jayaraj, B S; Prabhakar, A K; Chaya, S K; Vijaysimha, R

2013-01-01

Exposure to air pollution due to combustion of biomass fuels remains one of the significant risk factors for chronic respiratory diseases such as chronic bronchitis. There is a need to identify the minimum threshold level of biomass index that is significantly associated with chronic bronchitis. This study was undertaken to identify a threshold for biomass exposure index in a rural women population in Mysore district, south India. A cross-sectional survey was conducted in a representative population of Mysore and Nanjangud taluks. Eight villages each from Mysore and Nanjangud were randomly selected based on the list of villages from census 2001. A house-to-house survey was carried out by trained field workers using the Burden of Obstructive Diseases questionnaire, which evaluated the biomass smoke exposure and chronic bronchitis. All the women aged above 30 yr were included in the study. A total of 2011 women from Mysore and 1942 women from Nanjangud participated in the study. All women were non-smoking and used biomass fuels as the primary fuel for cooking. A threshold of biomass fuel exposure of 60 was identified on multivariate analysis in Mysore district after adjusting for age, passive smoking and working in a occupational exposure to dust, as the minimum required for a significant association with chronic bronchitis. One in every 20 women in Mysore district exposed to biomass fuel exposure index of 110 or more developed chronic bronchitis. The minimum threshold of biomass exposure index of 60 is necessary to have a significant risk of developing chronic bronchitis in women. The number needed to harm to develop chronic bronchitis reduces with increasing biomass exposure index and women residing in rural Nanjangud have a higher risk for developing chronic bronchitis as compared to women in Mysore.

Ionizing radiation exposures in treatments of solid neoplasms are not associated with subsequent increased risks of chronic lymphocytic leukemia.

Science.gov (United States)

Radivoyevitch, Tomas; Sachs, Rainer K; Gale, Robert Peter; Smith, Mitchell R; Hill, Brian T

2016-04-01

Exposure to ionizing radiation is not thought to cause chronic lymphocytic leukemia (CLL). Challenging this notion are recent data suggesting CLL incidence may be increased by radiation exposure from the atomic bombs (after many decades), uranium mining and nuclear power facility accidents. To assess the effects of therapeutic ionizing radiation for the treatment of solid neoplasms we studied CLL risks in data from the Surveillance, Epidemiology, and End Results (SEER) Program. Specifically, we compared the risks of developing CLL in persons with a 1(st) non-hematologic cancer treated with or without ionizing radiation. We controlled for early detection effects on CLL risk induced by surveillance after 1(st) cancer diagnoses by forming all-time cumulative CLL relative risks (RR). We estimate such CLL RR to be 1.20 (95% confidence interval, 1.17, 1.23) for persons whose 1(st) cancer was not treated with ionizing radiation and 1.00 (0.96, 1.05) for persons whose 1(st) cancer was treated with ionizing radiations. These results imply that diagnosis of a solid neoplasm is associated with an increased risk of developing CLL only in persons whose 1(st) cancer was not treated with radiation therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of UF4 physico-chemical properties on the assessment of the chronic exposure to this compound

International Nuclear Information System (INIS)

Ansoborlo, E.; Chalabreysse, J.

1990-01-01

A method was developed in order to assess uranium exposure hazards at work stations based on the industrial experience acquired by Comurhex Malvesi at Narbonne. Applied to uranium tetrafluoride (UF 4 ) the method involves 4 steps: 1. characterization of the industrial compound, including its physico-chemical properties (density, surface area, X-ray spectrum and uranium enrichment); 2. assessment of work station concentrations and particle size distribution (AMAD); 3. In vitro biological solubility with different synthetic fluids such as Gamble solutions with different gases or compounds added (oxygen or superoxide ions O 2 - ) in order to determine the solubility class D, W or Y; 4. workers' monitoring by routine measurements of urinary excretion completed, if necessary, by fecal excretion and γ-spectrometry. Results and present data on UF 4 are presented. 3 tabs., 4 figs [fr

Cell-metal interactions: A comparison of natural uranium to other common metals in renal cells and bone osteoblasts

International Nuclear Information System (INIS)

Milgram, S.; Carriere, M.; Thiebault, C.; Berger, P.; Khodja, H.; Gouget, B.

2007-01-01

Uranium acute intoxication has been documented to induce nephrotoxicity. Kidneys are the main target organs after short term exposures to high concentrations of the toxic, while chronic exposures lead to its accumulation in the skeleton. In this paper, chemical toxicity of uranium is investigated for rat osteoblastic bone cells and compared to results previously obtained on renal cells. We show that bone cells are less sensitive to uranium than renal cells. The influence of the chemical form on U cytotoxicity is demonstrated. For both cell types, a comparison of uranium toxicity with other metals or metalloids toxicities (Mn, Ni, Co, Cu, Zn, Se and Cd) permits classification of Cd, Zn, Se IV and Cu as the most toxic and Ni, Se VI , Mn and U as the least toxic. Chemical toxicity of natural uranium proves to be far less than that of cadmium. To try to explain the differences in sensitivities observed between metals and different cell types, cellular accumulations in cell monolayers are quantified by inductively coupled plasma-mass spectroscopy (ICP-MS), function of time or function of dose: lethal doses which simulate acute intoxications and sub-lethal doses which are more realistic with regard to environmentally metals concentrations. In addition to being more resistant, bone cells accumulated much more uranium than did renal cells. Moreover, for both cell models, Mn, U-citrate and U-bicarbonate are strongly accumulated whereas Cu, Zn and Ni are weakly accumulated. On the other hand, a strong difference in Cd behaviour between the two cell types is shown: whereas Cd is very weakly accumulated in bone cells, it is very strongly accumulated in renal cells. Finally, elemental distribution of the toxics is determined on a cellular scale using nuclear microprobe analysis. For both renal and osteoblastic cells, uranium was accumulated in as intracellular precipitates similar to those observed previously by SEM/EDS

Cell-metal interactions: A comparison of natural uranium to other common metals in renal cells and bone osteoblasts

Energy Technology Data Exchange (ETDEWEB)

Milgram, S. [Laboratoire Pierre Suee, CEA-CNRS UMR 9956, CEA/Saclay, 91191 Gif-sur-Yvette (France); Carriere, M. [Laboratoire Pierre Suee, CEA-CNRS UMR 9956, CEA/Saclay, 91191 Gif-sur-Yvette (France); Thiebault, C. [Laboratoire Pierre Suee, CEA-CNRS UMR 9956, CEA/Saclay, 91191 Gif-sur-Yvette (France); Berger, P. [Laboratoire Pierre Suee, CEA-CNRS UMR 9956, CEA/Saclay, 91191 Gif-sur-Yvette (France); Khodja, H. [Laboratoire Pierre Suee, CEA-CNRS UMR 9956, CEA/Saclay, 91191 Gif-sur-Yvette (France); Gouget, B. [Laboratoire Pierre Suee, CEA-CNRS UMR 9956, CEA/Saclay, 91191 Gif-sur-Yvette (France)]. E-mail: barbara.gouget@cea.fr

2007-07-15

Uranium acute intoxication has been documented to induce nephrotoxicity. Kidneys are the main target organs after short term exposures to high concentrations of the toxic, while chronic exposures lead to its accumulation in the skeleton. In this paper, chemical toxicity of uranium is investigated for rat osteoblastic bone cells and compared to results previously obtained on renal cells. We show that bone cells are less sensitive to uranium than renal cells. The influence of the chemical form on U cytotoxicity is demonstrated. For both cell types, a comparison of uranium toxicity with other metals or metalloids toxicities (Mn, Ni, Co, Cu, Zn, Se and Cd) permits classification of Cd, Zn, Se{sup IV} and Cu as the most toxic and Ni, Se{sup VI}, Mn and U as the least toxic. Chemical toxicity of natural uranium proves to be far less than that of cadmium. To try to explain the differences in sensitivities observed between metals and different cell types, cellular accumulations in cell monolayers are quantified by inductively coupled plasma-mass spectroscopy (ICP-MS), function of time or function of dose: lethal doses which simulate acute intoxications and sub-lethal doses which are more realistic with regard to environmentally metals concentrations. In addition to being more resistant, bone cells accumulated much more uranium than did renal cells. Moreover, for both cell models, Mn, U-citrate and U-bicarbonate are strongly accumulated whereas Cu, Zn and Ni are weakly accumulated. On the other hand, a strong difference in Cd behaviour between the two cell types is shown: whereas Cd is very weakly accumulated in bone cells, it is very strongly accumulated in renal cells. Finally, elemental distribution of the toxics is determined on a cellular scale using nuclear microprobe analysis. For both renal and osteoblastic cells, uranium was accumulated in as intracellular precipitates similar to those observed previously by SEM/EDS.

Assessment Of Depleted Uranium Contamination In Selective IRAQI Soils

International Nuclear Information System (INIS)

Mohammed, A.A.; Hussien, A.Sh.M.; Tawfiq, N.F.

2008-01-01

The aim of this research was to measure the radiation exposure rates in three selected Locations in southren part of Iraq (two in Nassireya, and one in Amara) resulted from the existence of depleted uranium in soil and metal pieces have been taken from destroyed tank and study mathmatically the concentration of Depleted Uranium by its dispersion from soil surface by winds and rains from 2003 to 2007. The exposure rates were measured using inspector device, while depleted uranium concentration in soil samples and tank's matal pieces were detected with Solid State Nuclear Track Detectors(SSNTDs). The wind and rain effects were considered in the calculation of dispersion effect on depleted uranium concentration in soil, where the wind effect were calculated with respect to the sites nature and soil conditions, and rain effect with respect to dispersive-convective equation for radionuclide in soil. The results obtained for the exposure rates were high near the penetrated surfac, moderate and low in soil and metal pices. The Depleted Uranium concentration in soil and metal pieces have the highest value in Nassireya. The results from dispersion calculation (wind & rain) showed that the depleted uranium concentration in 2008 will be less than the danger level and in allowable contamination range

Investigations into the Reusability of Amidoxime-Based Polymeric Adsorbents for Seawater Uranium Extraction

Energy Technology Data Exchange (ETDEWEB)

Kuo, Li-Jung [Marine; Pan, Horng-Bin [Department; Wai, Chien M. [Department; Byers, Margaret F. [Nuclear; Schneider, Erich [Nuclear; Strivens, Jonathan E. [Marine; Janke, Christopher J. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, United States; Das, Sadananda [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, United States; Mayes, Richard T. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, United States; Wood, Jordana R. [Marine; Schlafer, Nicholas [Marine; Gill, Gary A. [Marine

2017-09-29

The ability to re-use amidoxime-based polymeric adsorbents is a critical component in reducing the overall cost of the technology to extract uranium from seawater. This report describes an evaluation of adsorbent reusability in multiple re-use (adsorption/stripping) cycles in real seawater exposures with potassium bicarbonate (KHCO3) elution using several amidoxime-based polymeric adsorbents. The KHCO3 elution technique achieved ~100% recovery of uranium adsorption capacity in the first re-use. Subsequent re-uses showed significant drops in adsorption capacity. After the 4th re-use with the ORNL AI8 adsorbent, the 56-day adsorption capacity dropped to 28% of its original capacity. FTIR spectra revealed that there was a conversion of the amidoxime ligands to carboxylate groups during extended seawater exposure, becoming more significant with longer the exposure time. Ca and Mg adsorption capacities also increased with each re-use cycle supporting the hypothesis that long term exposure resulted in converting amidoxime to carboxylate, enhancing the adsorption of Ca and Mg. Shorter seawater exposure (adsorption/stripping) cycles (28 vs. 42 days) had higher adsorption capacities after re-use, but the shorter exposure cycle time did not produce an overall better performance in terms of cumulative exposure time. Recovery of uranium capacity in re-uses may also vary across different adsorbent formulations. Through multiple re-use the adsorbent AI8 can harvest 10 g uranium/kg adsorbent in ~140 days, using a 28-day adsorption/stripping cycle, a performance much better than would be achieved with a single use of the adsorbent through very long-term exposure (saturation capacity = 7.4 g U/kg adsorbent). A time dependent seawater exposure model to evaluate the cost associated with reusing amidoxime-based adsorbents in real seawater exposures was developed. The cost to extract uranium from seawater ranged from $610-830/kg U was predicted. Model simulation suggests that a short

Leukaemia and lymphoma among Czech uranium miners

International Nuclear Information System (INIS)

Tomasek, L.; Malatova, I.

2006-01-01

Leukaemia is one of the most sensitive cancers in relation to ionizing radiation. It is surprising that in studies of uranium miners, no risk of leukaemia in relation to cumulated radon exposure was observed (Darby et al, 1995). However, when the risk among Czech uranium miners was analyzed in dependence on duration of exposure, the trend was significant. These results were based on 10 cases (Tomasek, 1993). Since then the original cohort of 4320 miners has been extended by another cohort, now including nearly 10 000 uranium miners and the follow-up is longer by 10 years. The present report aims to analyze the risk of haemopoietic cancers in the Czech cohort accounting for both external and internal doses, similarly as reported by Jacobi and Roth (1995), and using available data on metal content and airborne particulates for dose estimates.The present results of follow-up show that increased risk of leukaemia among uranium miners is significantly associated with cumulated equivalent red bone marrow doses which is dominated by exposures to long lived alpha radionuclides in airborne particulates. The increased mortality is mainly observed decades after exposure and is consistent with estimated internal dose to red bone marrow. The estimated risk coefficient for leukaemia is consistent with results from other studies, however, further studies are needed to reduce uncertainty in the risk estimates. (N.C.)

Leukaemia and lymphoma among Czech uranium miners

Energy Technology Data Exchange (ETDEWEB)

Tomasek, L.; Malatova, I. [National Radiation Protection Institute, Prague (Czech Republic)

2006-07-01

Leukaemia is one of the most sensitive cancers in relation to ionizing radiation. It is surprising that in studies of uranium miners, no risk of leukaemia in relation to cumulated radon exposure was observed (Darby et al, 1995). However, when the risk among Czech uranium miners was analyzed in dependence on duration of exposure, the trend was significant. These results were based on 10 cases (Tomasek, 1993). Since then the original cohort of 4320 miners has been extended by another cohort, now including nearly 10 000 uranium miners and the follow-up is longer by 10 years. The present report aims to analyze the risk of haemopoietic cancers in the Czech cohort accounting for both external and internal doses, similarly as reported by Jacobi and Roth (1995), and using available data on metal content and airborne particulates for dose estimates.The present results of follow-up show that increased risk of leukaemia among uranium miners is significantly associated with cumulated equivalent red bone marrow doses which is dominated by exposures to long lived alpha radionuclides in airborne particulates. The increased mortality is mainly observed decades after exposure and is consistent with estimated internal dose to red bone marrow. The estimated risk coefficient for leukaemia is consistent with results from other studies, however, further studies are needed to reduce uncertainty in the risk estimates. (N.C.)

Radiation health and safety aspects in uranium milling

International Nuclear Information System (INIS)

Smart, B.C.

1982-01-01

This presentation deals mainly with radiation levels associated with the uranium milling operations, including yellowcake production. The regulation of uranium mills has not received much attention in the past because radiation levels have been generally low, and uranium milling has been substantially free of occupational illness. More attention is being directed towards minimizing exposures, and the Canadian Atomic Energy Control Board is working on new regulations which will reflect the recommendations of various hearings and the International Commission on Radiological Protection. Emphasis is now being placed on improving monitoring methods. At the beginning of 1982 a gamma dosimetry program will be put into effect for all uranium mine and mill workers. An improved method is also being sought to determine radon daughter exposures more accurately. It is expected that a better knowledge of monitoring and assessing thoron daughter levels in mine and mill facilities will be obtained soon. This radiation contribution will be included when calculating a combined radiation exposure factor for individual workers. Programs are underway to better monitor and assess uranium dust inhalation. Initial studies indicate that the present precautions taken to avoid dust inhalation at the mills are effective. A more complete study will be undertaken in 1982

Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure

Energy Technology Data Exchange (ETDEWEB)

Barillet, Sabrina, E-mail: sabrina.barillet@free.f [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.f [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Palluel, Olivier, E-mail: olivier.palluel@ineris.f [Ecotoxicological Risk Assessment Unit, INERIS (National Institute for Industrial Environment and Risks), Parc technologique ALATA, 60 550 Verneuil-en-Halatte (France); Porcher, Jean-Marc, E-mail: jean-marc.porcher@ineris.f [Ecotoxicological Risk Assessment Unit, INERIS (National Institute for Industrial Environment and Risks), Parc technologique ALATA, 60 550 Verneuil-en-Halatte (France); Devaux, Alain, E-mail: alain.devaux@entpe.f [Universite de Lyon, INRA, EFPA-SA, Environmental Science Laboratory (LSE), ENTPE, 69518 Vaulx en Velin cedex (France)

2011-02-15

Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose-response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect. - Research highlights: Depleted U bioconcentration factor is of about 1000 in zebrafish exposed to 20 {mu}g/L. Hepatic antioxidant disorders are noticed as soon as the first hours of exposure. DNA damage is induced in red blood cells after 20 d of exposure to 500 {mu}g DU/L. The brain cholinergic system (AChE activity) is impacted. - This study demonstrates that U is highly bioaccumulated in fish, resulting in biological disorders such as hepatic oxidative stress as well as genotoxic and neurotoxic events.

Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure

International Nuclear Information System (INIS)

Barillet, Sabrina; Adam-Guillermin, Christelle; Palluel, Olivier; Porcher, Jean-Marc; Devaux, Alain

2011-01-01

Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose-response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect. - Research highlights: → Depleted U bioconcentration factor is of about 1000 in zebrafish exposed to 20 μg/L. → Hepatic antioxidant disorders are noticed as soon as the first hours of exposure. → DNA damage is induced in red blood cells after 20 d of exposure to 500 μg DU/L. → The brain cholinergic system (AChE activity) is impacted. - This study demonstrates that U is highly bioaccumulated in fish, resulting in biological disorders such as hepatic oxidative stress as well as genotoxic and neurotoxic events.

Cancer hazard after intake of uranium. Survey

International Nuclear Information System (INIS)

Hedemann Jensen, P.; Soegaard-Hansen, J.; Ulbak, K.

2001-01-01

Depleted uranium has been used on tips of projectiles, which were used against tanks in the Gulf war and the war in Kosovo. Among the European soldiers that were in Kosovo some cases of leukaemia have been reported. Some have suggested that the uranium from the used projectiles may have caused these cases of leukaemia. This article presents information about the exposure risk from uranium as background information for doctors. (LN)

Cellular localization of uranium in the renal proximal tubules during acute renal uranium toxicity.

Science.gov (United States)

Homma-Takeda, Shino; Kitahara, Keisuke; Suzuki, Kyoko; Blyth, Benjamin J; Suya, Noriyoshi; Konishi, Teruaki; Terada, Yasuko; Shimada, Yoshiya

2015-12-01

Renal toxicity is a hallmark of uranium exposure, with uranium accumulating specifically in the S3 segment of the proximal tubules causing tubular damage. As the distribution, concentration and dynamics of accumulated uranium at the cellular level is not well understood, here, we report on high-resolution quantitative in situ measurements by high-energy synchrotron radiation X-ray fluorescence analysis in renal sections from a rat model of uranium-induced acute renal toxicity. One day after subcutaneous administration of uranium acetate to male Wistar rats at a dose of 0.5 mg uranium kg(-1) body weight, uranium concentration in the S3 segment of the proximal tubules was 64.9 ± 18.2 µg g(-1) , sevenfold higher than the mean renal uranium concentration (9.7 ± 2.4 µg g(-1) ). Uranium distributed into the epithelium of the S3 segment of the proximal tubules and highly concentrated uranium (50-fold above mean renal concentration) in micro-regions was found near the nuclei. These uranium levels were maintained up to 8 days post-administration, despite more rapid reductions in mean renal concentration. Two weeks after uranium administration, damaged areas were filled with regenerating tubules and morphological signs of tissue recovery, but areas of high uranium concentration (100-fold above mean renal concentration) were still found in the epithelium of regenerating tubules. These data indicate that site-specific accumulation of uranium in micro-regions of the S3 segment of the proximal tubules and retention of uranium in concentrated areas during recovery are characteristics of uranium behavior in the kidney. Copyright © 2015 John Wiley & Sons, Ltd.

Modeling exposure to depleted uranium in support of decommissioning at Jefferson Proving Ground, Indiana

Energy Technology Data Exchange (ETDEWEB)

Ebinger, M.H. [Los Alamos National Lab., NM (United States); Oxenburg, T.P. [Army Test and Evaluation Command, Aberdeen Proving Ground, MD (United States)

1997-02-01

Jefferson Proving Ground was used by the US Army Test and Evaluation Command for testing of depleted uranium munitions and closed in 1995 under the Base Realignment and Closure Act. As part of the closure of JPG, assessments of potential adverse health effects to humans and the ecosystem were conducted. This paper integrates recent information obtained from site characterization surveys at JPG with environmental monitoring data collected from 1983 through 1994 during DU testing. Three exposure scenarios were evaluated for potential adverse effects to human health: an occasional use scenario and two farming scenarios. Human exposure was minimal from occasional use, but significant risk were predicted from the farming scenarios when contaminated groundwater was used by site occupants. The human health risk assessments do not consider the significant risk posed by accidents with unexploded ordnance. Exposures of white-tailed deer to DU were also estimated in this study, and exposure rates result in no significant increase in either toxicological or radiological risks. The results of this study indicate that remediation of the DU impact area would not substantially reduce already low risks to humans and the ecosystem, and that managed access to JPG is a reasonable model for future land use options.

Chronic Toxic Metal Exposure and Cardiovascular Disease: Mechanisms of Risk and Emerging Role of Chelation Therapy.

Science.gov (United States)

Aneni, Ehimen C; Escolar, Esteban; Lamas, Gervasio A

2016-12-01

Over the last few decades, there has been a growing body of epidemiologic evidence linking chronic toxic metal exposure to cardiovascular disease-related morbidity and mortality. The recent and unexpectedly positive findings from a randomized, double-blind, multicenter trial of metal chelation for the secondary prevention of atherosclerotic cardiovascular disease (Trial to Assess Chelation Therapy (TACT)) have focused the discussion on the role of chronic exposure to toxic metals in the development and propagation of cardiovascular disease and the role of toxic metal chelation therapy in the secondary prevention of cardiovascular disease. This review summarizes the most recent evidence linking chronic toxic metal exposure to cardiovascular disease and examines the findings of TACT.

Health and environmental problems of using antiarmour munitions containing depleted uranium core

International Nuclear Information System (INIS)

Matousek, J.

2006-01-01

In the 1970s, core of depleted uranium commenced to be introduced into the breakthrough antitank munitions of various calibers and types in order to considerably enhance their effectiveness due to extremely high density in comparison with steel. The health and environmental threats of using this munitions and other weaponry where depleted uranium has been utilised as counterbalance stem from the pyrophoric character of uranium, burnt due to material deformation and friction when penetrating armour targets creating thus highly respirable aerosol of uranium oxides that are deposited in alveoli after being inhaled or in other tissues after being ingested. Composition and main properties of depleted uranium are presented. Chronic effects of deposited particles of uranium oxides are due to internal irradiation of sensitive organs at proceeding radioactive decay accompanied with alpha irradiation. Long-term internal irradiation by radionuclides producing alpha-rays leads to proved risk of increased incidence of carcinoma and leukaemia not to speak on chronic chemical toxicity of uranium, independent of its isotopic composition. Environmental impact of extensive use of munitions with depleted uranium in the recent armed conflicts is assessed. (authors)

Exposure of pregnant rats to uranium and restraint stress: Effects on postnatal development and behavior of the offspring

International Nuclear Information System (INIS)

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

2006-01-01

The effects on postnatal development and behavior were assessed in the offspring of female rats concurrently exposed to uranium (U) and restraint stress. Adult female rats were administered uranyl acetate dihydrate (UAD) in the drinking water at doses of 0, 40 and 80 mg/(kg day) for 4 weeks before mating with untreated males, as well as during pregnancy and lactation. One-half of female rats in each group were concurrently subjected to restraint (2 h/day). On gestation day 14, one-half of restrained and unrestrained rats were sacrificed in order to evaluate maternal toxicity and gestational parameters. Pups were evaluated for physical development, neuromotor maturation, and behavior. Uranium concentrations were also determined in various tissues of dams and fetuses. In all uranium-treated groups, the highest concentrations of this element were found in kidney and bone, being considerably higher than those in brain. Uranium levels in tissues of dam or fetuses were not significantly affected by restraint. No significant interactions between uranium and restraint could be observed in maternal toxicity. Moreover, no relevant effects of uranium, maternal restraint, or their combination were noted on developmental landmarks in the offspring. In the passive avoidance test, at 40 and 80 mg UAD/(kg day) restraint significantly modified passive avoidance acquisition (T1) and retention time (T2) 24 h later. However, no significant differences were observed on the Morris water maze test. The results of the present study indicate that, in general terms, exposure of female rats to UAD before mating with untreated males, as well as during gestation and lactation, did not cause relevant dose-related adverse effects on postnatal development and behavior of the offspring. The influence of stress was very limited

Assessment of nonpoint source chemical loading potential to watersheds containing uranium waste dumps associated with uranium exploration and mining, Browns Hole, Utah

Science.gov (United States)

Marston, Thomas M.; Beisner, Kimberly R.; Naftz, David L.; Snyder, Terry

2012-01-01

During August of 2008, 35 solid-phase samples were collected from abandoned uranium waste dumps, undisturbed geologic background sites, and adjacent streambeds in Browns Hole in southeastern Utah. The objectives of this sampling program were (1) to assess impacts on human health due to exposure to radium, uranium, and thorium during recreational activities on and around uranium waste dumps on Bureau of Land Management lands; (2) to compare concentrations of trace elements associated with mine waste dumps to natural background concentrations; (3) to assess the nonpoint source chemical loading potential to ephemeral and perennial watersheds from uranium waste dumps; and (4) to assess contamination from waste dumps to the local perennial stream water in Muleshoe Creek. Uranium waste dump samples were collected using solid-phase sampling protocols. Solid samples were digested and analyzed for major and trace elements. Analytical values for radium and uranium in digested samples were compared to multiple soil screening levels developed from annual dosage calculations in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act's minimum cleanup guidelines for uranium waste sites. Three occupancy durations for sites were considered: 4.6 days per year, 7.0 days per year, and 14.0 days per year. None of the sites exceeded the radium soil screening level of 96 picocuries per gram, corresponding to a 4.6 days per year exposure. Two sites exceeded the radium soil screening level of 66 picocuries per gram, corresponding to a 7.0 days per year exposure. Seven sites exceeded the radium soil screening level of 33 picocuries per gram, corresponding to a 14.0 days per year exposure. A perennial stream that flows next to the toe of a uranium waste dump was sampled, analyzed for major and trace elements, and compared with existing aquatic-life and drinking-water-quality standards. None of the water-quality standards were exceeded in the stream samples.

Training and replacing a 'lost generation' of uranium professionals

International Nuclear Information System (INIS)

Chalmers, M.S.

2007-01-01

It wasn't long ago, actually only a few years ago, when uranium companies and skilled uranium professionals receive little attention and limited interest from other sections of the mining and resource industries. Actually, there were many uranium professionals, whom in some cases, spent over a decade unwinding their CV's to limit the emphasis on uranium exploration and development from the past. Actually, when the bottom fell out of the uranium industry in the late 70's and early 80's there were literally tens of thousands of professionals internationally that were in a major regroup with their careers to get back into mining proper without the uranium connection and believe me, that wasn't always easy. As in most cases, there was no or limited places for uranium professionals wanting to stay in the industry and consequently, virtually all were forced to leave the sector. Who could have predicted that, after nearly 25 years of limited international investment and significant interest in new uranium exploration and development, that the price for yellowcake today would be in excess of US$100/pound? Concerns over energy security and global warming on top of the all-time high uranium price have really come together to make a true uranium renaissance. A renaissance which looks sounder and more sustainable than ever before. So, how is the industry facing a chronic shortage of experience and the huge task of training a multidisciplinary professional workforce going to cope? Effectively there is a 'lost generation' of professionals and very few people available or knowledgeable enough to train those new to the industry. This is a unique problem in the industry and likely more chronic than the other mining sectors, as typically the economic cycles are seven or eight years, not 25 years as has been seen with uranium

Analysis of genomic instability in bronchial cells from uranium miners

International Nuclear Information System (INIS)

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

1994-01-01

Epidemiological studies show that underground uranium miners have a radon progeny exposure-dependent increased risk for developing lung cancer. The odds ratio for lung cancer in uranium miners increase for all cumulative exposures above 99 Working Level Months. In addition, there is a strong multiplicative effect of cigarette smoking on the development of lung cancer in uranium miners. The purpose of this investigation was to determine whether or not early genetic changes, as indicated by genomic instability, can be detected in bronchial cells from uranium miners. Investigations of this nature may serve as a means of discovering sub-clinical disease and could lead to earlier detection of lung cancer and a better prognosis for the patient

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

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.

Influence of chronic x-ray exposure on adrenal glucocorticoid function and adrenocorticocyte membrane potential

International Nuclear Information System (INIS)

Gorban', Je.M.; Topol'nikova, N.V.

1998-01-01

The peculiarities of adrenal glucocorticoid function and membrane potential (MP) of zona fasciculata adrenocorticocyte (ACC) in rats after chronic x-ray exposure was studied. The changes of adrenal glucocorticoid function caused by chronic x-ray exposure within a relatively small period of irradiation (1.5 months) are obscure and manifest themselves only at physiological load. With the prolongation of the period (8 and 15 months), more considerable inhibition of the adrenal glucocorticoid function and disturbances in the membrane mechanisms of ACC MP level regulation are revealed

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.

High levels of uranium in groundwater of Ulaanbaatar, Mongolia

Energy Technology Data Exchange (ETDEWEB)

Nriagu, Jerome, E-mail: stoten@umich.edu [Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI 48109 (United States); Nam, Dong-Ha; Ayanwola, Titilayo A. [Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI 48109 (United States); Dinh, Hau [College of Literature, Science and Arts, University of Michigan (United States); Erdenechimeg, Erdenebayar; Ochir, Chimedsuren [Department Of Preventive Medicine, School Of Public Health, Health Science University, Mongolia, Ulaanbaatar (Mongolia); Bolormaa, Tsend-Ayush [Central Water Laboratory of Water Supply and Sewerage Authority (USUG), Ulaanbaatar (Mongolia)

2012-01-01

Water samples collected from 129 wells in seven of the nine sub-divisions of Ulaanbaatar were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) using Clean Lab methods. The levels of many trace elements were found to be low with the average concentrations (ranges in brackets) being 0.9 (< 0.1-7.9) {mu}g/L for As; 7.7 (0.12-177) {mu}g/L for Mn; 0.2 (< 0.05-1.9) {mu}g/L for Co; 16 (< 0.1-686) {mu}g/L for Zn; 0.7 (< 0.1-1.8) {mu}g/L for Se; < 0.1 (< 0.02-0.69) {mu}g/L for Cd; and 1.3 (< 0.02-32) {mu}g/L for Pb. The levels of uranium were surprisingly elevated (mean, 4.6 {mu}g/L; range < 0.01-57 {mu}g/L), with the values for many samples exceeding the World Health Organization's guideline of 15 {mu}g/L for uranium in drinking water. Local rocks and soils appear to be the natural source of the uranium. The levels of uranium in Ulaanbaatar's groundwater are in the range that has been associated with nephrotoxicity, high blood pressure, bone dysfunction and likely reproductive impairment in human populations. We consider the risk associated with drinking the groundwater with elevated levels of uranium in Ulaanbaatar to be a matter for some public health concern and conclude that the paucity of data on chronic effects of low level exposure is a risk factor for continuing the injury to many people in this city. - Highlights: Black-Right-Pointing-Pointer We analyzed water samples from wells across the city of Ulaanbaatar, Mongolia for total uranium along with arsenic, manganese, cobalt, zinc, selenium, cadmium and lead. Black-Right-Pointing-Pointer We found that compared to other trace metals and metalloids, the levels of uranium were surprisingly elevated with the values for many samples exceeding the World Health Organization's guideline for drinking water. Black-Right-Pointing-Pointer Local rocks and soils appear to be the natural source of the uranium. Black-Right-Pointing-Pointer The health risk associated with drinking the groundwater

Assessment of uncertainty associated with measuring exposure to radon and decay products in the French uranium miners cohort

International Nuclear Information System (INIS)

Allodji, Rodrigue S; Leuraud, Klervi; Laurier, Dominique; Bernhard, Sylvain; Henry, Stéphane; Bénichou, Jacques

2012-01-01

The reliability of exposure data directly affects the reliability of the risk estimates derived from epidemiological studies. Measurement uncertainty must be known and understood before it can be corrected. The literature on occupational exposure to radon ( 222 Rn) and its decay products reveals only a few epidemiological studies in which uncertainty has been accounted for explicitly. This work examined the sources, nature, distribution and magnitude of uncertainty of the exposure of French uranium miners to radon ( 222 Rn) and its decay products. We estimated the total size of uncertainty for this exposure with the root sum square (RSS) method, which may be an alternative when repeated measures are not available. As a result, we identified six main sources of uncertainty. The total size of the uncertainty decreased from about 47% in the period 1956–1974 to 10% after 1982, illustrating the improvement in the radiological monitoring system over time.

Deradiating the former uranium capital

International Nuclear Information System (INIS)

Merz, B.

1987-01-01

The city that once proclaimed itself The Uranium Capital of America is in the process of divorcing itself from the radioactive element - literally as well as symbolically. The last vestiges of uranium are being shoveled from the community. The removal is part of the federal Department of Energy's (DOE) Remedial Action program. It was established in 1972 to clean up areas of the country in which radiation exposure in excess of normal background levels could be attributed to wastes from DOE-operated uranium processing plants. Grand Junction was the first area to qualify. A good portion of the city is built on radioactive tailings - by-products of a uranium-processing industry. The DOE and the Environmental Protection Agency established guidelines for action levels of radiation. The standards were extrapolated from data from studies of lung cancer incidence in uranium miners in Europe and the US

Glucose administration attenuates spatial memory deficits induced by chronic low-power-density microwave exposure.

Science.gov (United States)

Lu, Yonghui; Xu, Shangcheng; He, Mindi; Chen, Chunhai; Zhang, Lei; Liu, Chuan; Chu, Fang; Yu, Zhengping; Zhou, Zhou; Zhong, Min

2012-07-16

Extensive evidence indicates that glucose administration attenuates memory deficits in rodents and humans, and cognitive impairment has been associated with reduced glucose metabolism and uptake in certain brain regions including the hippocampus. In the present study, we investigated whether glucose treatment attenuated memory deficits caused by chronic low-power-density microwave (MW) exposure, and the effect of MW exposure on hippocampal glucose uptake. We exposed Wistar rats to 2.45 GHz pulsed MW irradiation at a power density of 1 mW/cm(2) for 3 h/day, for up to 30 days. MW exposure induced spatial learning and memory impairments in rats. Hippocampal glucose uptake was also reduced by MW exposure in the absence or presence of insulin, but the levels of blood glucose and insulin were not affected. However, these spatial memory deficits were reversed by systemic glucose treatment. Our results indicate that glucose administration attenuates the spatial memory deficits induced by chronic low-power-density MW exposure, and reduced hippocampal glucose uptake may be associated with cognitive impairment caused by MW exposure. Copyright © 2012 Elsevier Inc. All rights reserved.

A Probabilistic Assessment of the Chemical and Radiological Risks of Chronic Exposure to Uranium in Freshwater Ecosystems

International Nuclear Information System (INIS)

Mathews, T.; Beaugelin-Seiller, K.; Garnier-Laplace, J.; Gilbin, R.; Adam, Ch.; Della-Vedova, C.

2009-01-01

Uranium (U) presents a unique challenge for ecological risk assessments (ERA) because it induces both chemical and radiological toxicity, and the relative importance of these two toxicities differs among the various U source terms (i.e., natural, enriched, depleted). We present a method for the conversion between chemical concentrations (μgL -1 ) and radiological dose rates (μGyh -1 ) for a defined set of reference organisms, and apply this conversion method to previously derived chemical and radiological benchmarks to determine the extent to which these benchmarks ensure radiological and chemical protection, respectively, for U in freshwater ecosystems. Results show that the percentage of species radiologically protected by the chemical benchmark decreases with increasing degrees of U enrichment and with increasing periods of radioactive decay. In contrast, the freshwater ecosystem is almost never chemically protected by the radiological benchmark, regardless of the source term or decay period considered, confirming that the risks to the environment from uranium's chemical toxicity generally outweigh those of its radiological toxicity. These results are relevant to developing water quality criteria that protect freshwater ecosystems from the various risks associated with the nuclear applications of U exploitation, and highlight the need for (1) further research on the speciation, bioavailability, and toxicity of U-series radionuclides under different environmental conditions, and (2) the adoption of both chemical and radiological benchmarks for coherent ERAS to be conducted in U-contaminated freshwater ecosystems. (authors)

Radiation monitoring of uranium workers

International Nuclear Information System (INIS)

1998-12-01

In order to manage radiological hazards in the workplace, it is necessary to have reliable measurements of workplace radiation levels and estimates of exposures and doses to workers. Over the past several years there have been many changes not only to the science of monitoring and dose assessment, but also to the regulatory framework. New International Commission on Radiological Protection (ICRP) recommendations on dose in ICRP Publication 60 (1991) and the implications of the ICRP's new respiratory tract model in ICRP Publication 66 (1994) are of particular importance. In addition, triggered by the act establishing the Canadian Nuclear Safety Commission (CNSC), which will replace the Atomic Energy Control Board (AECB), there is considerable activity in the review and development of regulatory guidance. Concurrent with these activities is the introduction of innovative mining procedures in Saskatchewan in order to extract uranium ore of particularly high grade. In view of these developments, the ACRP considered that a formal review of current monitoring practices would benefit both the CNSC and its licensees. In this report, 'uranium workers' refers to workers at uranium mines and mills, and workers at natural-uranium refineries, conversion, and fuel fabrication facilities; issues relating to long-term tailings management and to the handling of enriched materials are not addressed in this document. The report will have some relevance to workers in non-uranium mines and in industries handling naturally occurring radioactive materials (NORM) since, in some circumstances, these activities can present similar workplace radiation hazards. The report outlines the radiological hazards encountered in the Canadian uranium industry, and reviews current radiological monitoring practices and options; appendices include a glossary, a more technical discussion of monitoring methods, and an examination of errors and uncertainties in measurements of radon progeny and long

Chronic exposure to low frequency noise at moderate levels causes impaired balance in mice.

Directory of Open Access Journals (Sweden)

Haruka Tamura

Full Text Available We are routinely exposed to low frequency noise (LFN; below 0.5 kHz at moderate levels of 60-70 dB sound pressure level (SPL generated from various sources in occupational and daily environments. LFN has been reported to affect balance in humans. However, there is limited information about the influence of chronic exposure to LFN at moderate levels for balance. In this study, we investigated whether chronic exposure to LFN at a moderate level of 70 dB SPL affects the vestibule, which is one of the organs responsible for balance in mice. Wild-type ICR mice were exposed for 1 month to LFN (0.1 kHz and high frequency noise (HFN; 16 kHz at 70 dB SPL at a distance of approximately 10-20 cm. Behavior analyses including rotarod, beam-crossing and footprint analyses showed impairments of balance in LFN-exposed mice but not in non-exposed mice or HFN-exposed mice. Immunohistochemical analysis showed a decreased number of vestibular hair cells and increased levels of oxidative stress in LFN-exposed mice compared to those in non-exposed mice. Our results suggest that chronic exposure to LFN at moderate levels causes impaired balance involving morphological impairments of the vestibule with enhanced levels of oxidative stress. Thus, the results of this study indicate the importance of considering the risk of chronic exposure to LFN at a moderate level for imbalance.

Chronic caffeine exposure attenuates blast-induced memory deficit in mice.

Science.gov (United States)

Ning, Ya-Lei; Yang, Nan; Chen, Xing; Zhao, Zi-Ai; Zhang, Xiu-Zhu; Chen, Xing-Yun; Li, Ping; Zhao, Yan; Zhou, Yuan-Guo

2015-01-01

To investigate the effects of three different ways of chronic caffeine administration on blast- induced memory dysfunction and to explore the underlying mechanisms. Adult male C57BL/6 mice were used and randomly divided into five groups: control: without blast exposure, con-water: administrated with water continuously before and after blast-induced traumatic brain injury (bTBI), con-caffeine: administrated with caffeine continuously for 1 month before and after bTBI, pre-caffeine: chronically administrated with caffeine for 1 month before bTBI and withdrawal after bTBI, post-caffeine: chronically administrated with caffeine after bTBI. After being subjected to moderate intensity of blast injury, mice were recorded for learning and memory performance using Morris water maze (MWM) paradigms at 1, 4, and 8 weeks post-blast injury. Neurological deficit scoring, glutamate concentration, proinflammatory cytokines production, and neuropathological changes at 24 h, 1, 4, and 8 weeks post-bTBI were examined to evaluate the brain injury in early and prolonged stages. Adenosine A1 receptor expression was detected using qPCR. All of the three ways of chronic caffeine exposure ameliorated blast-induced memory deficit, which is correlated with the neuroprotective effects against excitotoxicity, inflammation, astrogliosis and neuronal loss at different stages of injury. Continuous caffeine treatment played positive roles in both early and prolonged stages of bTBI; pre-bTBI and post-bTBI treatment of caffeine tended to exert neuroprotective effects at early and prolonged stages of bTBI respectively. Up-regulation of adenosine A1 receptor expression might contribute to the favorable effects of chronic caffeine consumption. Since caffeinated beverages are widely consumed in both civilian and military personnel and are convenient to get, the results may provide a promising prophylactic strategy for blast-induced neurotrauma and the consequent cognitive impairment.

Measurement of the radioactive concentration in consumer's goods containing natural uranium and thorium and evaluation of the exposure by their utilization

International Nuclear Information System (INIS)

Yoshida, Masahiro; Satou, Shigerou; Ohhata, Tsutomu; Watanabe, Masatoshi; Ohyama, Ryutaro; Furuya, Hirotaka; Endou, Akira

2005-01-01

A number of consumer's goods which contain natural uranium and thorium are circulated in the familiar living environment. Based on various kinds of information sources, 20 kinds of these consumer's goods were collected and their radioactive concentrations were measured by using ICP-MS and Ge semiconductor detector. As this result, it was found that the concentrations of uranium and thorium in the consumer's goods used at home and industries were below 34 Bq/g and below 270 Bq/g, respectively. Next, the concentrations of daughter nuclides were not so different from the ones of uranium or thorium, which showed that the secular radioactive equilibrium held between both concentrations. In addition, the radiation exposures for public consumer were evaluated when four kinds of typical consumer's goods frequently used in daily life are utilized. The results computed by MCNP-4C code were below 250 μSv/y. (author)

Inhalation of uranium ores

International Nuclear Information System (INIS)

Stuart, B.O.; Jackson, P.O.

1975-01-01

In previous studies the biological dispositions of individual long-lived alpha members of the uranium chain ( 238 U, 234 U and 230 Th) were determined during and following repeated inhalation exposures of rats to pitchblende (26 percent U 3 O 8 ) ore. Although finely dispersed ore in secular equilibrium was inhaled, 230 Th/ 234 U radioactivity ratios in the lungs rose from 1.0 to 2.5 during 8 weeks of exposures and increased to 9.2 by four months after cessation of exposures. Marked non-equilibrium levels were also found in the tracheobronchial lymph nodes, kidneys, liver, and femur. Daily exposures of beagle dogs to high levels of this ore for 8 days resulted in lung 230 Th/ 234 U ratios of >2.0. Daily exposures of dogs to lower levels (0.1 mg/1) for 6 months, with sacrifice 15 months later, resulted in lung and thoracic lymph node 230 Th/ 234 U ratios ranging from 3.6 to 9 and nearly 7, respectively. The lungs of hamsters exposed to carnotite (4 percent U 3 O 8 ) ore in current lifespan studies show 230 Th/ 234 U ratios as high as 2.0 during daily inhalation of this ore in secular equilibrium. Beagle dogs sacrificed after several years of daily inhalations of the same carnotite ore plus radon daughters also showed marked non-equilibrium ratios of 230 Th/ 234 U, ranging from 5.6 to 7.4 in lungs and 6.2 to 9.1 in thoracic lymph nodes. This pattern of higher retention of 230 Th than 234 U in lungs, thoracic lymph nodes, and other tissues is thus consistent for two types of uranium ore among several species and suggests a reevaluation of maximum permissible air concentrations of ore, currently based only on uranium content

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.

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.

Particulate matter air pollution exposure: role in the development and exacerbation of chronic obstructive pulmonary disease

Directory of Open Access Journals (Sweden)

Sean H Ling

2009-06-01

Full Text Available Sean H Ling, Stephan F van EedenJames Hogg iCAPTURE Centre for Pulmonary and Cardiovascular Research and Heart and Lung Institute, University of British Columbia, Vancouver, British Columbia, CanadaAbstract: Due to the rapid urbanization of the world population, a better understanding of the detrimental effects of exposure to urban air pollution on chronic lung disease is necessary. Strong epidemiological evidence suggests that exposure to particulate matter (PM air pollution causes exacerbations of pre-existing lung conditions, such as, chronic obstructive pulmonary disease (COPD resulting in increased morbidity and mortality. However, little is known whether a chronic, low-grade exposure to ambient PM can cause the development and progression of COPD. The deposition of PM in the respiratory tract depends predominantly on the size of the particles, with larger particles deposited in the upper and larger airways and smaller particles penetrating deep into the alveolar spaces. Ineffective clearance of this PM from the airways could cause particle retention in lung tissues, resulting in a chronic, low-grade inflammatory response that may be pathogenetically important in both the exacerbation, as well as, the progression of lung disease. This review focuses on the adverse effects of exposure to ambient PM air pollution on the exacerbation, progression, and development of COPD.Keywords: chronic obstructive pulmonary disease, particulate matter, air pollution, alveolar macrophage

Alpha-risk: a European project on the quantification of risks associated with multiple radiation exposures

International Nuclear Information System (INIS)

Laurier, D.; Monchaux, G.; Tirmarche, M.; Darby, S.; Cardis, E.; Binks, K.; Hofmann, W.; Muirhead, C.

2006-01-01

The Alpha-Risk research project is being conducted within the Sixth European Framework Programme (EC-FP6, 2005 -2008). It aims to improve the quantification of risks associated with multiple exposures, taking into account the contribution of different radionuclides and external exposure using specific organ dose calculations. The Alpha-Risk Consortium involves 18 partners from 9 countries, and is coordinated by the IRSN. Its composition allows a multidisciplinary collaboration between researchers in epidemiology, dosimetry, statistics, modelling and risk assessment. Alpha-Risk brings together major epidemiological studies in Europe, which are able to evaluate long-term health effects of internal exposure from radionuclides. It includes large size cohort and case-control studies, with accurate registration of individual annual exposures: uranium miner studies, studies on lung cancer and indoor radon exposure, and studies of lung cancer and leukaemia among nuclear workers exposed to transuranic nuclides (mainly uranium and plutonium), for whom organ doses will be reconstructed individually. The contribution of experts in dosimetry will allow the calculation of organ doses in presence of multiple exposures (radon decay products, uranium dust and external gamma exposure). Expression of the risk per unit organ dose will make it possible to compare results with those from other populations exposed to external radiation. The multidisciplinary approach of Alpha-Risk promotes the development of coherent and improved methodological approaches regarding risk modelling. A specific work - package is dedicated to the integration of results and their use for risk assessment, especially for radon. Alpha-Risk will contribute to a better understanding of long-term health risks following chronic low doses from internal exposures. The project also has the great potential to help resolve major public health concerns about the effects of low and/or protracted exposures, especially

Contribution o the assessment of the environmental risk associated with uranium releases in the Ritord drainage basin

International Nuclear Information System (INIS)

Beaugelin-Seiller, K.; Garnier-Laplace, J.; Gilbin, R.; Della-Vedova, C.

2008-01-01

This document reports the application to aquatic environments and more particularly to the case of a drainage basin of methods of assessment of the environmental risk presented in another report. The objective is to determine the environmental risk related to releases of uranium from ancient mining sites. The method is applied to available data to diagnose a possible chemical and/or radiological risk due to these releases. Should the occasion occurs, probabilistic approaches are used to refine the assessment of the possible risk identified by the screening. After a presentation of the context, the different screening steps are reported: methodology (exposure analysis, effect analysis, and risk characterization), deterministic characterization of the chronic radiological risk, deterministic characterization of the chronic chemical risk. The next part reports the probabilistic assessment of the chemical or radiological risk. In conclusion, the authors indicate actions to be performed to better analyse exposures, and desirable actions to better analyse effects

Injury of the blood-testies barrier after low-dose-rate chronic radiation exposure

Energy Technology Data Exchange (ETDEWEB)

Sohn, Young Hoon; Bae Min Ji; Lee, Chang Geun; Yang, Kwang Mo; Jur, Kyu; Kim, Jong Sun [Dongnam Institute of Radiological and Medical Science, Busan (Korea, Republic of)

2014-04-15

The systemic effect of radiation increases in proportionally with the dose and dose rate. Little is known concerning the relationships between harmful effects and accumulated dose, which is derived from continuous low-dose rate radiation exposure. Recent our studies show that low-dose-rate chronic radiation exposure (3.49 mGy/h) causes adverse effects in the testis at a dose of 2 Gy (6 mGy/h). However, the mechanism of the low-dose-rate 2 Gy irradiation induced testicular injury remains unclear. The present results indicate that low-dose rate chronic radiation might affect the BTB permeability, possibly by decreasing levels of ZO-1, Occludin-1, and NPC-2. Furthermore, our results suggest that there is a risk of male infertility through BTB impairment even with low-dose-rate radiation if exposure is continuous.

Developmental sub-chronic exposure to chlorpyrifos reduces anxiety-related behavior in zebrafish larvae

Science.gov (United States)

Richendrfer, Holly; Pelkowski, Sean D.; Colwill, Ruth M.; Créton, Robbert

2013-01-01

Neurobehavioral disorders such as anxiety, autism, and attention deficit hyperactivity disorders are typically influenced by genetic and environmental factors. Although several genetic risk factors have been identified in recent years, little is known about the environmental factors that either cause neurobehavioral disorders or contribute to their progression in genetically predisposed individuals. One environmental factor that has raised concerns is chlorpyrifos, an organophosphate pesticide that is widely used in agriculture and is found ubiquitously in the environment. In the present study, we examined the effects of sub-chronic chlorpyrifos exposure on anxiety-related behavior during development using zebrafish larvae. We found that sub-chronic exposure to 0.01 or 0.1 μM chlorpyrifos during development induces specific behavioral defects in 7-day-old zebrafish larvae. The larvae displayed decreases in swim speed and thigmotaxis, yet no changes in avoidance behavior were seen. Exposure to 0.001 μM chlorpyrifos did not affect swimming, thigmotaxis, or avoidance behavior and exposure to 1 μM chlorpyrifos induced behavioral defects, but also induced defects in larval morphology. Since thigmotaxis, a preference for the edge, is an anxiety-related behavior in zebrafish larvae, we propose that sub-chronic chlorpyrifos exposure interferes with the development of anxiety-related behaviors. The results of this study provide a good starting point for examination of the molecular, cellular, developmental, and neural mechanisms that are affected by environmentally relevant concentrations of organophosphate pesticides. A more detailed understanding of these mechanisms is important for the development of predictive models and refined health policies to prevent toxicant-induced neurobehavioral disorders. PMID:22579535

No effect of low-level chronic neonicotinoid exposure on bumblebee learning and fecundity

Directory of Open Access Journals (Sweden)

Saija Piiroinen

2016-03-01

Full Text Available In recent years, many pollinators have declined in abundance and diversity worldwide, presenting a potential threat to agricultural productivity, biodiversity and the functioning of natural ecosystems. One of the most debated factors proposed to be contributing to pollinator declines is exposure to pesticides, particularly neonicotinoids, a widely used class of systemic insecticide. Also, newly emerging parasites and diseases, thought to be spread via contact with managed honeybees, may pose threats to other pollinators such as bumblebees. Compared to honeybees, bumblebees could be particularly vulnerable to the effects of stressors due to their smaller and more short-lived colonies. Here, we studied the effect of field-realistic, chronic clothianidin exposure and inoculation with the parasite Nosema ceranae on survival, fecundity, sugar water collection and learning using queenless Bombus terrestris audax microcolonies in the laboratory. Chronic exposure to 1 ppb clothianidin had no significant effects on the traits studied. Interestingly, pesticide exposure in combination with additional stress caused by harnessing bees for Proboscis Extension Response (PER learning assays, led to an increase in mortality. In contrast to previous findings, the bees did not become infected by N. ceranae after experimental inoculation with the parasite spores, suggesting variability in host resistance or parasite virulence. However, this treatment induced a slight, short-term reduction in sugar water collection, potentially through stimulation of the immune system of the bees. Our results suggest that chronic exposure to 1 ppb clothianidin does not have adverse effects on bumblebee fecundity or learning ability.

Early changes of lymphocyte RNA and serum immunoglobulins following chronic exposure to benzene

Energy Technology Data Exchange (ETDEWEB)

Chircu, V.; Ionescu, M.; Zgoan

Hematologic and immunochemical investigations carried out in 270 workers with chronic exposure to benzene demonstrated changes of the nucleologram and of the area of lymphocyte nucleoli as well as disorders of the humoral immune response revealed by radial immunodiffusion. The numerical rise of bi- and polynucleolated cells, of cells with irregular macronucleoli as well as an enlargement of the nucleolar area are assumed to reflect an increase of the endolymphocytic amounts of RNA. An increased capacity of immunoglobulin formation, particularly of IgM, was also observed. All these changes are considered as early signs of an enhanced immune reactivity following chronic exposure to benzene.

Chronic exposure to microcystin-LR affected mitochondrial DNA maintenance and caused pathological changes of lung tissue in mice

International Nuclear Information System (INIS)

Li, Xinxiu; Xu, Lizhi; Zhou, Wei; Zhao, Qingya; Wang, Yaping

2016-01-01

Microcystin-LR (MC-LR), an important variant of cyanotoxin family, was frequently encountered in the contaminated aquatic environment and taken as a potent hepatotoxin. However, a little was known on the association between the long-term MC-LR exposure and lung damage. In this study, we investigated the changes of the pulmonary histopathology, mitochondrial DNA (mtDNA) integrity and the expression of mtDNA encoded genes in the mice with chronic exposed to MC-LR at different concentrations (1, 5, 10, 20 and 40 μg/L) for 12 months. Our results showed that the long-term and persistent exposure to MC-LR disturbed the balance of redox system, influenced mtDNA stability, changed the expression of mitochondrial genes in the lung cells. Notably, MC-LR exposure influenced the level of inflammatory cytokines and resulted in thickening of the alveolar septa. In conclusion, chronic exposure to MC-LR affected mtDNA maintenance, and caused lung impairment in mice. - Highlights: • A simulated natural exposure to MC-LR caused the lung pathological changes. • The chronic exposure disturbed the redox system balance of lung tissue cells. • The chronic exposure impaired the mtDNA stability and mitochondria function. • The lung was one of the vulnerable organs to MC-LR exposure in mice. - Long-term exposure to MC-LR in drinking water disturbed the balance of redox system, affected mitochondrial DNA maintenance and caused lung impairment in mice.

Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

Directory of Open Access Journals (Sweden)

Balmes John

2005-05-01

Full Text Available Abstract Background Exposure to environmental tobacco smoke (ETS, which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies. Methods Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing COPD. Participants were recruited from all 48 contiguous U.S. states by random digit dialing. Lifetime ETS exposure was ascertained by structured telephone interview. We used a standard epidemiologic approach to define COPD based on a self-reported physician diagnosis of chronic bronchitis, emphysema, or COPD. Results Higher cumulative lifetime home and work exposure were associated with a greater risk of COPD. The highest quartile of lifetime home ETS exposure was associated with a greater risk of COPD, controlling for age, sex, race, personal smoking history, educational attainment, marital status, and occupational exposure to vapors, gas, dusts, or fumes during the longest held job (OR 1.55; 95% CI 1.09 to 2.21. The highest quartile of lifetime workplace ETS exposure was also related to a greater risk of COPD (OR 1.36; 95% CI 1.002 to 1.84. The population attributable fraction was 11% for the highest quartile of home ETS exposure and 7% for work exposure. Conclusion ETS exposure may be an important cause of COPD. Consequently, public policies aimed at preventing public smoking may reduce the burden of COPD-related death and disability, both by reducing direct smoking and ETS exposure.

The specifics of uranium exploration in remote areas of western Australia

International Nuclear Information System (INIS)

Tsurikov, N.

2009-01-01

The uranium exploration activity in Western Australia has increased significantly in the last two years. Total currently identified uranium resources are in order of 100,000 tons of U 3 O 8 and it is likely that more uranium deposits will be found in the State. The exploration activity is typically carried out in very remote locations in Western Australia and, frequently, on the land that is subject to the Australian Native Title Act (1993) - in the areas where the potential radiation exposure of the Traditional Land Owners has to be considered. Aboriginal groups are an integral part of dynamic ecosystems, for whom to separate man from nature is a convention with little meaning when dealing with environmental impact, and this needs to be taken into account by uranium exploration companies. Indigenous peoples potential exposure to radiation as a result of uranium exploration cannot be modelled based on common assumptions. Indigenous people may be at a higher risk of radiation exposure at and around uranium exploration sites that may not have been adequately rehabilitated due to, for example: travelling on dusty roads in open vehicles, sitting on the ground, living and sleeping in temporary structures with earth floors, lack of adequate washing facilities, eating local biota and cooking in the ground, recreational activities (particularly by children). The radiation protection regulations in Western Australia are complex and somewhat confusing as there are three State government departments administering different regulations that may be applicable to uranium exploration. The paper discusses the specifics of required radiation monitoring and potential radiation exposure assessments in remote areas of Western Australia. The methods for the co-operation between exploration companies, government departments, and Traditional Owners to ensure safe and successful uranium exploration are also discussed.(Author)

Effect of uranium (VI) on two sulphate-reducing bacteria cultures from a uranium mine site

International Nuclear Information System (INIS)

Martins, Monica; Faleiro, Maria Leonor; Chaves, Sandra; Tenreiro, Rogerio; Costa, Maria Clara

2010-01-01

This work was conducted to assess the impact of uranium (VI) on sulphate-reducing bacteria (SRB) communities obtained from environmental samples collected on the Portuguese uranium mining area of Urgeirica. Culture U was obtained from a sediment, while culture W was obtained from sludge from the wetland of that mine. Temperature gradient gel electrophoresis (TGGE) was used to monitor community changes under uranium stress conditions. TGGE profiles of dsrB gene fragment demonstrated that the initial cultures were composed of SRB species affiliated with Desulfovibrio desulfuricans, Desulfovibrio vulgaris and Desulfomicrobium spp. (sample U), and by species related to D. desulfuricans (sample W). A drastic change in SRB communities was observed as a result of uranium (VI) exposure. Surprisingly, SRB were not detected in the uranium removal communities. Such findings emphasize the need of monitoring the dominant populations during bio-removal studies. TGGE and phylogenetic analysis of the 16S rRNA gene fragment revealed that the uranium removal consortia are composed by strains affiliated to Clostridium genus, Caulobacteraceae and Rhodocyclaceae families. Therefore, these communities can be attractive candidates for environmental biotechnological applications associated to uranium removal.

Occupational exposures and chronic obstructive pulmonary disease (COPD): comparison of a COPD-specific job exposure matrix and expert-evaluated occupational exposures.

Science.gov (United States)

Kurth, Laura; Doney, Brent; Weinmann, Sheila

2017-03-01

To compare the occupational exposure levels assigned by our National Institute for Occupational Safety and Health chronic obstructive pulmonary disease-specific job exposure matrix (NIOSH COPD JEM) and by expert evaluation of detailed occupational information for various jobs held by members of an integrated health plan in the Northwest USA. We analysed data from a prior study examining COPD and occupational exposures. Jobs were assigned exposure levels using 2 methods: (1) the COPD JEM and (2) expert evaluation. Agreement (Cohen's κ coefficients), sensitivity and specificity were calculated to compare exposure levels assigned by the 2 methods for 8 exposure categories. κ indicated slight to moderate agreement (0.19-0.51) between the 2 methods and was highest for organic dust and overall exposure. Sensitivity of the matrix ranged from 33.9% to 68.5% and was highest for sensitisers, diesel exhaust and overall exposure. Specificity ranged from 74.7% to 97.1% and was highest for fumes, organic dust and mineral dust. This COPD JEM was compared with exposures assigned by experts and offers a generalisable approach to assigning occupational exposure. 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/.

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

Risk assessment applications for determining cleanup limits for uranium in treated and untreated soils

International Nuclear Information System (INIS)

Armstrong, A.Q.; Layton, D.W.; Rutz, E.E.

1994-01-01

Uranium-contaminated soils are present at various locations across the US where uranium was processed for nuclear fuels or atomic weapons. Important issues relative to such contamination include the assessment of potential health risks associated with human exposures to the residual uranium and the determination of safe levels of uranium in soils that have been treated by a given technology. This paper discusses various risk assessment considerations that must be dealt with when developing cleanup limits for uranium in treated and untreated soils. Key issues addressed include alternative land use scenarios, potential exposure pathways, characterization of the bioavailability of uranium compounds in food and water, a brief overview of health risks associated with uranium and its daughter products as well as a summary of considerations for development of risk-based cleanup limits for uranium in soils

Hair analysis following chronic smoked-drugs-of-abuse exposure in adults and their toddler: a case report

OpenAIRE

Papaseit, Esther; Joya, Xavier; Velasco, Marta; Civit, Ester; Mota, Pau; Bertran, Marta; Vall, Oriol; Garcia-Algar, Oscar

2011-01-01

Abstract Introduction Over the past two decades, the study of chronic cocaine and crack cocaine exposure in the pediatric population has been focused on the potential adverse effects, especially in the prenatal period and early childhood. Non-invasive biological matrices have become an essential tool for the assessment of a long-term history of drug of abuse exposure. Case report We analyze the significance of different biomarker values in hair after chronic crack exposure in a two-year-old C...

Uranium mill tailings remedial action technology

International Nuclear Information System (INIS)

Hartley, J.N.; Gee, G.W.

1984-01-01

The uranium milling process involves the hydrometallurgical extraction of uranium from ores and the resultant generation of large quantities of waste referred to as tailings. Uranium mill tailings have been identified as requiring remediation because they contain residual radioactive material that is not removed in the milling process. Potential radiation exposure can result from direct contact with the tailings, from radon gas emitted by the tailings, and from radioactive contamination of groundwater. As a result, the technology developed under the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) and the US Nuclear Regulatory Commission (NRC) Uranium Recovery Program have focused on radon control, groundwater contamination and the long-term protection of the containment system. This paper briefly summarizes the UMTRAP and NRC remedial action technology development. 33 references, 9 figures, 5 tables

Impacts of chronic sublethal exposure to clothianidin on winter honeybees.

Science.gov (United States)

Alkassab, Abdulrahim T; Kirchner, Wolfgang H

2016-07-01

A wide application of systemic pesticides and detection of their residues in bee-collected pollen and nectar at sublethal concentrations led to the emergence of concerns about bees' chronic exposure and possible sublethal effects on insect pollinators. Therefore, special attention was given to reducing unintentional intoxications under field conditions. The sensitivity of winter bees throughout their long lifespan to residual exposure of pesticides is not well known, since most previous studies only looked at the effects on summer bees. Here, we performed various laboratory bioassays to assess the effects of clothianidin on the survival and behavior of winter bees. Oral lethal and sublethal doses were administered throughout 12-day. The obtained LD50 values at 48, 72, 96 h and 10 days were 26.9, 18.0, 15.1 and 9.5 ng/bee, respectively. Concentrations <20 µg/kg were found to be sublethal. Oral exposure to sublethal doses was carried out for 12-day and, the behavioral functions were tested on the respective 13th day. Although slight reductions in the responses at the concentrations 10 and 15 µg/kg were observed, all tested sublethal concentrations had showed non-significant effects on the sucrose responsiveness, habitation of the proboscis extension reflex and olfactory learning performance. Nevertheless, chronic exposure to 15 µg/kg affected the specificity of the early long-term memory (24 h). Since the tested concentrations were in the range of field-relevant concentrations, our results strongly suggest that related-effects on winter and summer bees' sensitivity should also be studied under realistic conditions.

Measurement methods and optimization of radiation protection: the case of internal exposure by inhalation to natural uranium compounds

International Nuclear Information System (INIS)

Degrange, J.P.; Gibert, B.

1998-01-01

The aim of this presentation is to discuss the ability of different measurement methods (air sampling and biological examinations) to answer to demands in the particular case of internal exposure by inhalation to natural uranium compounds. The realism and the sensitivity of each method are studied, on the base of new dosimetric models of the ICRP. The ability of analysis of these methods in order to optimize radiation protection are then discussed. (N.C.)

Lung cancer risk, exposure to radon and tobacco consumption in a nested case-control study of French uranium miners

International Nuclear Information System (INIS)

Leuraud, K.; Billon, S.; Bergot, D.; Tirmarche, M.; Laurier, D.; Caer, S.; Quesne, B.

2006-01-01

Introduction: A nested case-control study was conducted among the French uranium miners cohort in order to assess the effect of protract ed radon exposure on lung cancer risk taking into account tobacco consumption. Material and methods: One hundred uranium miners employed by the French company CEA-COGEMA and who died of a lung cancer between 1980 and 1994 were identified as cases among the cohort. For each case, five controls were randomly matched on birth period and attained age at the time of death of the corresponding case. Cumulated radon exposure during employment was reconstructed for each of these 100 cases and 500 controls. Smoking habits were retrospectively determined from three complementary sources: 1) medical files, 2) forms filled in by occupational physicians and 3) questionnaires applied in face-to-face interviews, phone calls or mailings. Analysis was performed by conditional logistic regression using a linear excess relative risk (ERR) model. A multiplicative model was fitted to assess the joint effect of radon exposure and smoking on lung cancer risk. Results: Smoking status was established for 62 cases and 320 controls and two categories ('ever smokers' vs. 'never smokers') were defined. Ninety percent of the cases and 73% of the controls were classified as 'ever smokers'. Mean five-year lagged cumulated radon exposures were 82.0 and 47.6 working level months (WLM) for the cases and the controls, respectively. The excess relative risk per WLM (ERR/WLM) was 1.1% with a 95%-confidence interval (CI) of 0.2-2.0%. When adjusting for smoking, radon exposure effect was little modified (ERR/WLM = 0.8%, 95% -CI = 0.1- 2.8%). The effect of smoking on lung cancer risk was comparable to results reported in previous miners cohorts (OR = 3.04, 95% -CI = 1.20-7.70). Discussion: A consequent effort was carried out to collect smoking status from three sources for the miners included in this nested case-control study. This analysis shows that, when adjusting on

Uranium in the tissue of occupationally exposed workers

International Nuclear Information System (INIS)

Campbell, E.E.; McInroy, J.F.; Schulte, H.F.

1975-04-01

Data are presented on the content of uranium in tissue samples from deceased occupationally exposed uranium workers. Data on the distribution in lungs, lymph nodes, liver, kidneys, and bone tissues are correlated with available data on the urinary excretion of U during the period of occupational exposure. (CH)

Cancer epidemiology in respiratory system among uranium miners

International Nuclear Information System (INIS)

Moraes, A.

1976-11-01

A summary of some published papers about cancer in respiratory system among uranium miners is presented. A comparative table relating cancer cases among uranium miners is shown. A table relating cases among miners in Checoslovaquia and cumulative exposure levels due to radon daughter products is also given [pt

Investigation of rare chronic lipoid pneumonia associated with occupational exposure to paraffin aerosol.

Science.gov (United States)

Han, Chenghong; Liu, Lihai; Du, Shiping; Mei, Jianhua; Huang, Ling; Chen, Min; Lei, Yongliang; Qian, Junwen; Luo, Jianyong; Zhang, Meibian

2016-09-30

Occupational exposure to paraffin is an infrequent cause of lipoid pneumonia (LP) and related data are scare. We investigated the possible relationship between three rare cases of chronic LP and occupational exposure to paraffin aerosol in an iron foundry. The three cases of LP and their workplaces were investigated using data from field investigations, air monitoring, pulmonary radiological examinations, cell staining, and lung biopsies. The patients had long-term occupational exposure to paraffin. X-ray diffraction testing revealed that the raw material from the workshop was paraffin crystal. The air concentrations of paraffin aerosol in workplaces were significantly higher than outdoor background levels. Small diffuse and miliary shadows with unclear edges were observed throughout the whole lungs via radiography. Computed tomography revealed diffuse punctate nodules and a high density of stripe-like shadows in both lungs (ground-glass opacity in a lower lobe, and a mass-like lesion and high translucent area near the bottom of the lung). Lipid-laden macrophages were found in the sputum and bronchial lavage. A broadened alveolar septum and local focal fibrosis were also discovered via lung biopsy. The inflammatory reaction in the lung tissues appeared to resolve over time. These three rare cases of chronic LP in workers during molding and repair processes were associated with occupational paraffin aerosol exposure. Therefore, primary prevention is essential for molding or repairing workers in the iron foundry, and a differential diagnosis of occupational chronic LP (vs. pneumoconiosis) should be considered when treating these workers.

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)

Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

OpenAIRE

Balmes John; Eisner Mark D; Katz Patricia P; Trupin Laura; Yelin Edward H; Blanc Paul D

2005-01-01

Abstract Background Exposure to environmental tobacco smoke (ETS), which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies. Methods Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing...

RIBE at an inter-organismic level: A study on genotoxic effects in Daphnia magna exposed to waterborne uranium and a uranium mine effluent.

Science.gov (United States)

Reis, P; Lourenço, J; Carvalho, F P; Oliveira, J; Malta, M; Mendo, S; Pereira, R

2018-05-01

The induction of RIBE (Radiation Induced Bystander Effect) is a non-target effect of low radiation doses that has already been verified at an inter-organismic level in fish and small mammals. Although the theoretical impact in the field of environmental risk assessment (ERA) is possible, there is a gap of knowledge regarding this phenomenon in invertebrate groups and following environmentally relevant exposures. To understand if RIBE should be considered for ERA of radionuclide-rich wastewaters, we exposed Daphnia magna (uranium mine effluent for 48 h, and to a matching dose of waterborne uranium (55.3 μg L -1 ). Then the exposed organisms were placed (24 and 48 h) in a clean medium together with non-exposed neonates. The DNA damage observed for the non-exposed organisms was statistically significant after the 24 h cohabitation for both uranium (neonates p = 0.002; 5 d-old daphnids p = uranium mine effluent exposure (only for neonates p = 0.042). After 48 h cohabitation significant results were obtained only for uranium exposure (neonates p = 0.017; 5 d-old daphnids p = 0.013). Although there may be some variability associated to age and exposure duration, the significant DNA damage detected in non-exposed organisms clearly reveals the occurrence of RIBE in D. magna. The data obtained and here presented are a valuable contribution for the discussion about the relevance of RIBE for environmental risk assessment. Copyright © 2018 Elsevier B.V. All rights reserved.

Chronic ethanol exposure inhibits distraction osteogenesis in a mouse model: Role of the TNF signaling axis

International Nuclear Information System (INIS)

Wahl, Elizabeth C.; Aronson, James; Liu, Lichu; Liu, Zhendong; Perrien, Daniel S.; Skinner, Robert A.; Badger, Thomas M.; Ronis, Martin J.J.; Lumpkin, Charles K.

2007-01-01

Tumor necrosis factor-alpha (TNF-α) is an inflammatory cytokine that modulates osteoblastogenesis. In addition, the demonstrated inhibitory effects of chronic ethanol exposure on direct bone formation in rats are hypothetically mediated by TNF-α signaling. The effects in mice are unreported. Therefore, we hypothesized that in mice (1) administration of a soluble TNF receptor 1 derivative (sTNF-R1) would protect direct bone formation during chronic ethanol exposure, and (2) administration of recombinant mouse TNF-α (rmTNF-α) to ethanol naive mice would inhibit direct bone formation. We utilized a unique model of limb lengthening (distraction osteogenesis, DO) combined with liquid diets to measure chronic ethanol's effects on direct bone formation. Chronic ethanol exposure resulted in increased marrow TNF, IL-1, and CYP 2E1 RNA levels in ethanol-treated vs. control mice, while no significant weight differences were noted. Systemic administration of sTNF-R1 during DO (8.0 mg/kg/2 days) to chronic ethanol-exposed mice resulted in enhanced direct bone formation as measured radiologically and histologically. Systemic rmTNF-α (10 μg/kg/day) administration decreased direct bone formation measures, while no significant weight differences were noted. We conclude that chronic ethanol-associated inhibition of direct bone formation is mediated to a significant extent by the TNF signaling axis in a mouse model

Changes in the α4β2* nicotinic acetylcholine system during chronic controlled alcohol exposure in nonhuman primates.

Science.gov (United States)

Hillmer, Ansel T; Tudorascu, Dana L; Wooten, Dustin W; Lao, Patrick J; Barnhart, Todd E; Ahlers, Elizabeth O; Resch, Leslie M; Larson, Julie A; Converse, Alexander K; Moore, Colleen F; Schneider, Mary L; Christian, Bradley T

2014-05-01

The precise nature of modifications to the nicotinic acetylcholine receptor (nAChR) system in response to chronic ethanol exposure is poorly understood. The present work used PET imaging to assay α4β2* nAChR binding levels of eight rhesus monkeys before and during controlled chronic ethanol intake. [(18)F]Nifene PET scans were conducted prior to alcohol exposure, and then again after at least 8 months controlled ethanol exposure, including 6 months at 1.5 g/kg/day following a dose escalation period. Receptor binding levels were quantified with binding potentials (BPND) using the cerebellum as a reference region. Alcohol self-administration was assessed as average daily alcohol intake during a 2 month free drinking period immediately following controlled alcohol. Significant decreases in α4β2* nAChR binding were observed in both frontal and insular cortex in response to chronic ethanol exposure. During chronic alcohol exposure, BPND in the lateral geniculate region correlated positively with the amount of alcohol consumed during free drinking. The observed decreases in nAChR availability following chronic alcohol consumption suggest alterations to this receptor system in response to repeated alcohol administration, making this an important target for further study in alcohol abuse and alcohol and nicotine codependence. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Application of bimodal distribution to the detection of changes in uranium concentration in drinking water collected by random daytime sampling method from a large water supply zone.

Science.gov (United States)

Garboś, Sławomir; Święcicka, Dorota

2015-11-01

The random daytime (RDT) sampling method was used for the first time in the assessment of average weekly exposure to uranium through drinking water in a large water supply zone. Data set of uranium concentrations determined in 106 RDT samples collected in three runs from the water supply zone in Wroclaw (Poland), cannot be simply described by normal or log-normal distributions. Therefore, a numerical method designed for the detection and calculation of bimodal distribution was applied. The extracted two distributions containing data from the summer season of 2011 and the winter season of 2012 (nI=72) and from the summer season of 2013 (nII=34) allowed to estimate means of U concentrations in drinking water: 0.947 μg/L and 1.23 μg/L, respectively. As the removal efficiency of uranium during applied treatment process is negligible, the effect of increase in uranium concentration can be explained by higher U concentration in the surface-infiltration water used for the production of drinking water. During the summer season of 2013, heavy rains were observed in Lower Silesia region, causing floods over the territory of the entire region. Fluctuations in uranium concentrations in surface-infiltration water can be attributed to releases of uranium from specific sources - migration from phosphate fertilizers and leaching from mineral deposits. Thus, exposure to uranium through drinking water may increase during extreme rainfall events. The average chronic weekly intakes of uranium through drinking water, estimated on the basis of central values of the extracted normal distributions, accounted for 3.2% and 4.1% of tolerable weekly intake. Copyright © 2015 Elsevier Ltd. All rights reserved.

Determination of Adsorption Capacity and Kinetics of Amidoxime-Based Uranium Adsorbent Braided Material in Unfiltered Seawater Using a Flume Exposure System

International Nuclear Information System (INIS)

Gill, Gary A.; Kuo, Li-Jung; Strivens, Jonathan E.; Park, Jiyeon; Bonheyo, George T.; Jeters, Robert T.; Schlafer, Nicholas J.; Wood, Jordana R.

2015-01-01

PNNL has developed a recirculating flume system for exposing braided adsorbent material to natural seawater under realistic temperature and flow-rate exposure conditions. The flumes are constructed of transparent acrylic material; they allow external light to pass into the flumes and permit photosynthetic growth of naturally present marine organisms (biofouling). Because the system consists of two flumes, replicate experiments can be conducted in which one of the flumes can be manipulated relative to the other. For example, one flume can be darkened to eliminate light exposure by placing a black tarp over the flume such that dark/light experiments can be conducted. Alternatively, two different braided adsorbents can be exposed simultaneously with no potential cross contamination issues. This report describes the first use of the PNNL flume system to study the impact of biofouling on adsorbent capacity. Experiments were conducted with the ORNL AI8 braided adsorbent material in light-exposed and darkened flumes for a 42-day exposure experiment. The major objective of this effort is to develop a system for the exposure of braided adsorbent material to unfiltered seawater, and to demonstrate the system by evaluating the performance of adsorption material when it is exposed to natural marine biofouling as it would be when the technology is used in the marine environment. Exposures of amidoxime-based polymeric braid adsorbents prepared by Oak Ridge Natural Laboratory (ORNL) were exposed to ambient seawater at 20°C in a flume system. Adsorption kinetics and adsorption capacity were assessed using time series determinations of uranium adsorption and one-site ligand saturation modeling. Biofouling in sunlight surface seawater has the potential to significantly add substantial biogenic mass to adsorption material when it is exposed for periods greater than 21 days. The observed biomass increase in the light flume was approximately 80% of the adsorbent mass after 42 days

Determination of Adsorption Capacity and Kinetics of Amidoxime-Based Uranium Adsorbent Braided Material in Unfiltered Seawater Using a Flume Exposure System

Energy Technology Data Exchange (ETDEWEB)

Gill, Gary A. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Sciences Lab.; Kuo, Li-Jung [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Sciences Lab.; Strivens, Jonathan E. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Sciences Lab.; Park, Jiyeon [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Sciences Lab.; Bonheyo, George T. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Sciences Lab.; Jeters, Robert T. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Sciences Lab.; Schlafer, Nicholas J. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Sciences Lab.; Wood, Jordana R. [Pacific Northwest National Lab. (PNNL), Sequim, WA (United States). Marine Sciences Lab.

2015-08-31

PNNL has developed a recirculating flume system for exposing braided adsorbent material to natural seawater under realistic temperature and flow-rate exposure conditions. The flumes are constructed of transparent acrylic material; they allow external light to pass into the flumes and permit photosynthetic growth of naturally present marine organisms (biofouling). Because the system consists of two flumes, replicate experiments can be conducted in which one of the flumes can be manipulated relative to the other. For example, one flume can be darkened to eliminate light exposure by placing a black tarp over the flume such that dark/light experiments can be conducted. Alternatively, two different braided adsorbents can be exposed simultaneously with no potential cross contamination issues. This report describes the first use of the PNNL flume system to study the impact of biofouling on adsorbent capacity. Experiments were conducted with the ORNL AI8 braided adsorbent material in light-exposed and darkened flumes for a 42-day exposure experiment. The major objective of this effort is to develop a system for the exposure of braided adsorbent material to unfiltered seawater, and to demonstrate the system by evaluating the performance of adsorption material when it is exposed to natural marine biofouling as it would be when the technology is used in the marine environment. Exposures of amidoxime-based polymeric braid adsorbents prepared by Oak Ridge Natural Laboratory (ORNL) were exposed to ambient seawater at 20°C in a flume system. Adsorption kinetics and adsorption capacity were assessed using time series determinations of uranium adsorption and one-site ligand saturation modeling. Biofouling in sunlight surface seawater has the potential to significantly add substantial biogenic mass to adsorption material when it is exposed for periods greater than 21 days. The observed biomass increase in the light flume was approximately 80% of the adsorbent mass after 42 days

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.

28 CFR 79.52 - Criteria for eligibility for claims by uranium millers.

Science.gov (United States)

2010-07-01

... uranium millers. 79.52 Section 79.52 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CLAIMS UNDER THE RADIATION EXPOSURE COMPENSATION ACT Eligibility Criteria for Claims by Uranium Millers § 79.52 Criteria for eligibility for claims by uranium millers. To establish eligibility for compensation under...

Reproductive impairment in the zebrafish, Danio rerio, upon chronic exposure to 1,2,3-trichlorobenzene.

NARCIS (Netherlands)

Roex, E.W.M.; Giovannangelo, M.E.C.A.; van Gestel, C.A.M.

2001-01-01

Most organic pollutants are supposed to act via the mechanism of nonpolar narcosis upon acute exposure. Because the chronic effects of these compounds are still relatively unknown, in this study a chronic toxicity experiment was performed with zebrafish, Danio rerio, exposed to 1, 2,

Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn Exposure on Sea Cucumbers (Apostichopus japonicus

Directory of Open Access Journals (Sweden)

Li Li

2016-01-01

Full Text Available Acute and chronic toxicity tests were conducted with sea cucumber (Apostichopus japonicus exposed to heavy metals. Acute toxicity values (96 h LC50 were 2.697, 0.133, and 1.574 mg L−1 for Zn, Cu, and Cd, respectively, and were ranked in order of toxicity: Cu > Cd > Zn. Under chronic metal exposure the specific growth rates of sea cucumbers decreased with the increase of metal concentration for all the three metals. After acute metal exposure, the oxygen consumption rate (OCR decreased. The OCRs in all groups were significantly different than control (P muscle > intestine in natural sea water. After chronic Zn, Cu, and Cd exposure, the change pattern of HK and PK in respiratory tree, muscle, and intestine varied slightly. However, the activity of the enzyme showed a general trend of increase and then decrease and the higher the exposure concentration was, the earlier the highest point of enzyme activity was obtained.

An investigation into radiation exposures in underground non-uranium mines in Western Australia

International Nuclear Information System (INIS)

Hewson, G.S.; Ralph, M.I.

1994-01-01

A preliminary investigation into the radiological conditions in underground non-uranium mines in Western Australia has been undertaken. Measurements of radon concentration by passive track etch monitors and absorbed gamma dose-rate by thermoluminescent dosimetry were undertaken in 27 mines. These mines employed 2173 workers which represented nearly 80% of the underground workforce at the time of the survey. Radon progeny concentration by both grab sampling and automatic devices were undertaken at selected mines. Radiological conditions in all surveyed underground workplaces were such that it was estimated that most underground workers should not exceed an annual effective dose of 5 mSv. The average annual effective dose across all mines was estimated to be 1.4±1.0 mSv, ranging from 0.4 mSv for a nickel mine to 4.2 mSv for a coal mine. Radon progeny exposure contributed approximately 70% of the total effective dose. The estimated average annual effective dose in three coal mines (employing 297 workers) was 2.9±1.5 mSv. On the basis of this preliminary investigation it was concluded that no regulatory controls are specifically required to limit radiation exposures in Western Australian underground mines. (author)

Elution of Uranium and Transition Metals from Amidoxime-Based Polymer Adsorbents for Sequestering Uranium from Seawater

Energy Technology Data Exchange (ETDEWEB)

Pan, Horng-Bin; Kuo, Li-Jung; Wai, Chien M.; Miyamoto, Naomi; Joshi, Ruma; Wood, Jordana R.; Strivens, Jonathan E.; Janke, Christopher J.; Oyola, Yatsandra; Das, Sadananda; Mayes, Richard T.; Gill, Gary A.

2015-11-30

High-surface-area amidoxime and carboxylic acid grafted polymer adsorbents developed at Oak Ridge National Laboratory were tested for sequestering uranium in a flowing seawater flume system at the PNNL-Marine Sciences Laboratory. FTIR spectra indicate that a KOH conditioning process is necessary to remove the proton from the carboxylic acid and make the sorbent effective for sequestering uranium from seawater. The alkaline conditioning process also converts the amidoxime groups to carboxylate groups in the adsorbent. Both Na₂CO₃-H₂O₂ and hydrochloric acid elution methods can remove ~95% of the uranium sequestered by the adsorbent after 42 days of exposure in real seawater. The Na₂CO₃-H₂O₂ elution method is more selective for uranium than conventional acid elution. Iron and vanadium are the two major transition metals competing with uranium for adsorption to the amidoxime-based adsorbents in real seawater.

The Longitudinal Effects of Chronic Mediated Exposure to Political Violence on Ideological Beliefs About Political Conflicts Among Youths.

Science.gov (United States)

Gvirsman, Shira Dvir; Huesmann, L Rowell; Dubow, Eric F; Landau, Simha F; Boxer, Paul; Shikaki, Khalil

This study examines the effects of chronic (i.e., repeated and cumulative) mediated exposure to political violence on ideological beliefs regarding political conflict. It centers on these effects on young viewers, from preadolescents to adolescents. Ideological beliefs refers here to support of war, perception of threat to one's nation, and normative beliefs concerning aggression toward the out-group. A longitudinal study was conducted on a sample of Israeli and Palestinian youths who experience the Israeli-Palestinian conflict firsthand ( N = 1,207). Two alternative hypotheses were tested: that chronic exposure via the media increases support for war and aggression and elevates feeling of threat, or that chronic exposure via the media strengthens preexisting beliefs. Results demonstrated that higher levels of exposure were longitudinally related to stronger support for war. Regarding normative beliefs about aggression and threat to one's nation, mediated exposure reinforced initial beliefs, rendering the youths more extreme in their attitudes. These results mostly support the conceptualization of the relation between media violence and behaviors as "reciprocally determined" or "reinforcing spirals." The results are also discussed in light of the differences found between the effect of exposure to political violence firsthand and exposure via the media.

Inhalation hazards to uranium miners

International Nuclear Information System (INIS)

Cross, F.T.

1982-01-01

This project is investigating levels of uranium mine air contaminants, using both large and small experimental animals to model human respiratory system disease. Lung cancer and deaths by degenerative lung disease have reached epidemic proportions 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, pneumonconiosis and emphysema

Inhalation hazards to uranium miners

International Nuclear Information System (INIS)

Cross, F.T.

1983-01-01

This project is investigating levels or uranium mine air contaminants, using both large and small experimental animals to model human respiratory system disease. Lung cancer and deaths by degenerative lung disease have reached epidemic proportions 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

Incorporation and distribution of tritium in rats after chronic exposure to various tritiated compounds

International Nuclear Information System (INIS)

Takeda, H.

1991-01-01

Rats were chronically exposed to tritiated water ( 3 HHO) and several tritiated organic compounds ([ 3 H]leucine, [ 3 H]lysine, [ 3 H]glucose, [ 3 H]glucosamine, [ 3 H]thymidine and [ 3 H]uridine) dissolved in their drinking water. An analysis of tritium in wet and dry tissues of rats at the end of 22 days' chronic exposure showed that the chemical form of the ingested tritium was more important for tritium uptake in dry tissues than in wet tissues. The highest concentrations of OBT (organically bound tritium) were found in rats exposed to tritiated amino acids ([sup (3)/H]lysine and [ 3 H]leucine), 4-9 times higher than those in rats exposed to 3 HHO. The next highest concentrations were found in rats exposed to [ 3 H]uridine., The result of radiation dose estimations at the end of chronic exposure showed the contribution of OBT to total dose rate was higher in the tissues of rats exposed to tritiated organic compounds than that after exposure to 3 HHO. The differences between total dose rates from 3 HHO and those from tritiated organic compounds were within a factor of 2. (author)

Chemical toxicity and radiological health detriment associated with the inhalation of various enrichments of uranium

International Nuclear Information System (INIS)

3C Limited, Queen Square House, 18-21 Queen Square, Bristol BS1 4NH (United Kingdom))" data-affiliation=" (SR3C Limited, Queen Square House, 18-21 Queen Square, Bristol BS1 4NH (United Kingdom))" >Bryant, P A

2014-01-01

The occupational risks associated with the chemical toxicity of uranium can be overlooked during the processing, handling and storage of the material, as the radioactivity of the material is often used alone to assess the health consequences of exposure to uranium compounds. This note provides a summary of the current United Kingdom occupational standards for uranium based on radiation dose and/or chemical toxicity with a particular focus on intake via inhalation. A simple model is subsequently presented to allow a comparison to be drawn between the occupational exposure standard for chemical toxicity and radiological dose limit. Using these data a set of suggested limits on occupational exposure to airborne uranium is proposed that indicate where the legal annual radiological dose limit for workers or the Health and Safety Executive occupational exposure standard for chemical toxicity are at risk of being breached. (note)

Depleted and natural uranium: chemistry and toxicological effects.

Science.gov (United States)

Craft, Elena; Abu-Qare, Aquel; Flaherty, Meghan; Garofolo, Melissa; Rincavage, Heather; Abou-Donia, Mohamed

2004-01-01

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

Transformation of human osteoblast cells to the tumorigenic phenotype by depleted uranium-uranyl chloride.

OpenAIRE

Miller, A C; Blakely, W F; Livengood, D; Whittaker, T; Xu, J; Ejnik, J W; Hamilton, M M; Parlette, E; John, T S; Gerstenberg, H M; Hsu, H

1998-01-01

Depleted uranium (DU) is a dense heavy metal used primarily in military applications. Although the health effects of occupational uranium exposure are well known, limited data exist regarding the long-term health effects of internalized DU in humans. We established an in vitro cellular model to study DU exposure. Microdosimetric assessment, determined using a Monte Carlo computer simulation based on measured intracellular and extracellular uranium levels, showed that few (0.0014%) cell nuclei...

Lung Cancer Mortality among Uranium Gaseous Diffusion Plant Workers: A Cohort Study 1952–2004

Directory of Open Access Journals (Sweden)

LW Figgs

2013-07-01

Full Text Available Background: 9%–15% of all lung cancers are attributable to occupational exposures. Reports are disparate regarding elevated lung cancer mortality risk among workers employed at uranium gaseous diffusion plants. Objective: To investigate whether external radiation exposure is associated with lung cancer mortality risk among uranium gaseous diffusion workers. Methods: A cohort of 6820 nuclear industry workers employed from 1952 to 2003 at the Paducah uranium gaseous diffusion plant (PGDP was assembled. A job-specific exposure matrix (JEM was used to determine likely toxic metal exposure categories. In addition, radiation film badge dosimeters were used to monitor cumulative external ionizing radiation exposure. International Classification for Disease (ICD codes 9 and 10 were used to identify 147 lung cancer deaths. Logistic and proportional hazards regression were used to estimate lung cancer mortality risk. Results: Lung cancer mortality risk was elevated among workers who experienced external radiation >3.5 mrem and employment duration >12 years. Conclusion: Employees of uranium gaseous diffusion plants carry a higher risk of lung cancer mortality; the mortality is associated with increased radiation exposure and duration of employment.

Chronic obstructive pulmonary disease and occupational exposure to silica.

Science.gov (United States)

Rushton, Lesley

2007-01-01

Prolonged exposure to high levels of silica has long been known to cause silicosis This paper evaluates the evidence for an increased risk of chronic obstructive pulmonary disease (COPD) in occupations and industries in which exposure to crystalline silica is the primary exposure, with a focus on the magnitude of risks and levels of exposure causing disabling health effects. The literature suggests consistently elevated risks of developing COPD associated with silica exposure in several occupations, including the construction industry; tunneling; cement industry; brick manufacturing; pottery and ceramic work; silica sand, granite and diatomaceous earth industries; gold mining; and iron and steel founding, with risk estimates being high in some, even after taking into account the effect of confounders like smoking. Average dust levels vary from about 0.5 mg.m3 to over 10 mg.m3 and average silica levels from 0.04 to over 5 mg.m3, often well above occupational standards. Factors influencing the variation from industry to industry in risks associated with exposure to silica-containing dusts include (a) the presence of other minerals in the dust, particularly when associated with clay minerals; (b) the size of the particles and percentage of quartz; (c) the physicochemical characteristics, such as whether the dust is freshly fractured. Longitudinal studies suggest that loss of lung function occurs with exposure to silica dust at concentrations of between 0.1 and 0.2 mg.m3, and that the effect of cumulative silica dust exposure on airflow obstruction is independent of silicosis. Nevertheless, a disabling loss of lung function in the absence of silicosis would not occur until between 30 and 40 years exposure.

Influence of Regularity of Exposure to Chronic Stress on the Pattern of Habituation of Pituitary-Adrenal Hormones, Prolactin and Glucose.

Science.gov (United States)

Martí; Armario

1997-05-01

The effect of regularity of exposure to two different chronic stressors (noise or immobilization (IMO)) on the pattern of habituation of pituitary-adrenal (PA) hormones, prolactin and glucose was evaluated in adult male rats. Animals were chronically subjected to either regular or irregular time schedule of noise (30 min/day) or IMO (2 h/day) for two weeks. The day after the last stress session the rats were killed without stress or after having been subjected to 30 min of the homotypic stressor. Whereas regular noise did not affect food intake, body weight gain or adrenal weight, irregular noise decreased body weight gain and induced a moderate adrenal hypertrophy. In addition, previous daily exposure to regular but not to irregular noise reduced both prolactin and corticosterone responses to acute noise. In contrast, glucose response to acute noise was reduced after both regular and irregular exposure to chronic noise. Either regular or irregular exposure to chronic IMO decreased food intake and body weight and increased adrenal weight to the same extent. Likewise, no influence of regularity of exposure to chronic IMO on corticosterone and prolactin responses to acute IMO was observed. However, habituation of the ACTH response to acute IMO was observed in rats subjected to chronic regular IMO, but not in rats subjected to chronic irregular IMO. Finally, acute IMO-induced hyperglycemia diminished to the same extent after regular and irregular IMO. From these results we can conclude that: first, the process of habituation of the PA axis to chronic stress is greatly dependent upon factors such as regularity of exposure to the stressor and stressor intensity, and second, the influence of regularity on the pattern of habituation to a repeated stressor is dependent on the physiological variable we are dealing with.

The effect of chronic exposure to fatty acids

DEFF Research Database (Denmark)

Xiao, J.; Gregersen, S.; Kruhøffer, Mogens

2001-01-01

Fatty acids affect insulin secretion of pancreatic beta-cells. Investigating gene expression profiles may help to characterize the underlying mechanism. INS-1 cells were cultured with palmitate (0, 50, and 200 microM) for up to 44 d. Insulin secretion and expressions of 8740 genes were studied. We...... 44, respectively. Genes involved in fatty acid oxidation were up-regulated, whereas those involved in glycolysis were down-regulated with 200 microM palmitate. A suppression of insulin receptor and insulin receptor substate-2 gene expression was found on d 44 in cells cultured at 200 microM palmitate....... In conclusion, chronic exposure to low palmitate alters insulin secretion as well as gene expression. The number of genes that changed expression was palmitate dose and exposure time dependent. Randle's fatty acid-glucose cycle seems to be operative on the gene transcription level. A modification of expression...

Chronic zinc exposure decreases the surface expression of NR2A-containing NMDA receptors in cultured hippocampal neurons.

Directory of Open Access Journals (Sweden)

Jia Zhu

Full Text Available Zinc distributes widely in the central nervous system, especially in the hippocampus, amygdala and cortex. The dynamic balance of zinc is critical for neuronal functions. Zinc modulates the activity of N-methyl-D-aspartate receptors (NMDARs through the direct inhibition and various intracellular signaling pathways. Abnormal NMDAR activities have been implicated in the aetiology of many brain diseases. Sustained zinc accumulation in the extracellular fluid is known to link to pathological conditions. However, the mechanism linking this chronic zinc exposure and NMDAR dysfunction is poorly understood.We reported that chronic zinc exposure reduced the numbers of NR1 and NR2A clusters in cultured hippocampal pyramidal neurons. Whole-cell and synaptic NR2A-mediated currents also decreased. By contrast, zinc did not affect NR2B, suggesting that chronic zinc exposure specifically influences NR2A-containg NMDARs. Surface biotinylation indicated that zinc exposure attenuated the membrane expression of NR1 and NR2A, which might arise from to the dissociation of the NR2A-PSD-95-Src complex.Chronic zinc exposure perturbs the interaction of NR2A to PSD-95 and causes the disorder of NMDARs in hippocampal neurons, suggesting a novel action of zinc distinct from its acute effects on NMDAR activity.

The Neurological Significance of Abnormal Natural Killer Cell Activity in Chronic Toxigenic Mold Exposures

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Ebere Anyanwu

2003-01-01

Full Text Available Toxigenic mold activities produce metabolites that are either broad-spectrum antibiotics or mycotoxins that are cytotoxic. Indoor environmental exposure to these toxigenic molds leads to adverse health conditions with the main outcome measure of frequent neuroimmunologic and behavioral consequences. One of the immune system disorders found in patients presenting with toxigenic mold exposure is an abnormal natural killer cell activity. This paper presents an overview of the neurological significance of abnormal natural killer cell (NKC activity in chronic toxigenic mold exposure. A comprehensive review of the literature was carried out to evaluate and assess the conditions under which the immune system could be dysfunctionally interfered with leading to abnormal NKC activity and the involvement of mycotoxins in these processes. The functions, mechanism, the factors that influence NKC activities, and the roles of mycotoxins in NKCs were cited wherever necessary. The major presentations are headache, general debilitating pains, nose bleeding, fevers with body temperatures up to 40�C (104�F, cough, memory loss, depression, mood swings, sleep disturbances, anxiety, chronic fatigue, vertigo/dizziness, and in some cases, seizures. Although sleep is commonly considered a restorative process that is important for the proper functioning of the immune system, it could be disturbed by mycotoxins. Most likely, mycotoxins exert some rigorous effects on the circadian rhythmic processes resulting in sleep deprivation to which an acute and transient increase in NKC activity is observed. Depression, psychological stress, tissue injuries, malignancies, carcinogenesis, chronic fatigue syndrome, and experimental allergic encephalomyelitis could be induced at very low physiological concentrations by mycotoxin-induced NKC activity. In the light of this review, it is concluded that chronic exposures to toxigenic mold could lead to abnormal NKC activity with a wide

Idaho National Engineering and Environmental Laboratory Site Report on the Production and Use of Recycled Uranium

Energy Technology Data Exchange (ETDEWEB)

L. C. Lewis; D. C. Barg; C. L. Bendixsen; J. P. Henscheid; D. R. Wenzel; B. L. Denning

2000-09-01

Recent allegations regarding radiation exposure to radionuclides present in recycled uranium sent to the gaseous diffusion plants prompted the Department of Energy to undertake a system-wide study of recycled uranium. Of particular interest, were the flowpaths from site to site operations and facilities in which exposure to plutonium, neptunium and technetium could occur, and to the workers that could receive a significant radiation dose from handling recycled uranium. The Idaho National Engineering and Environmental Laboratory site report is primarily concerned with two locations. Recycled uranium was produced at the Idaho Chemical Processing Plant where highly enriched uranium was recovered from spent fuel. The other facility is the Specific Manufacturing Facility (SMC) where recycled, depleted uranium is manufactured into shapes for use by their customer. The SMC is a manufacturing facility that uses depleted uranium metal as a raw material that is then rolled and cut into shapes. There are no chemical processes that might concentrate any of the radioactive contaminant species. Recyclable depleted uranium from the SMC facility is sent to a private metallurgical facility for recasting. Analyses on the recast billets indicate that there is no change in the concentrations of transuranics as a result of the recasting process. The Idaho Chemical Processing Plant was built to recover high-enriched uranium from spent nuclear fuel from test reactors. The facility processed diverse types of fuel which required uniquely different fuel dissolution processes. The dissolved fuel was passed through three cycles of solvent extraction which resulted in a concentrated uranyl nitrate product. For the first half of the operating period, the uranium was shipped as the concentrated solution. For the second half of the operating period the uranium solution was thermally converted to granular, uranium trioxide solids. The dose reconstruction project has evaluated work exposure and

The role of environmental tobacco exposure and Helicobacter pylori infection in the risk of chronic tonsillitis in children

Directory of Open Access Journals (Sweden)

Chen Li’e

Full Text Available ABSTRACT CONTEXT AND OBJECTIVE: Helicobacter pylori (H. pylori is a chronic infectious pathogen with high prevalence. This study investigated the interaction between environmental tobacco exposure and H. pylori infection on the incidence of chronic tonsillitis in Chinese children. DESIGN AND SETTING: Cross-sectional study performed in an outpatient clinic in China. METHODS: Pediatric patients with chronic tonsillitis were enrolled. H. pylori infection was determined according to the presence of H. pylori CagA IgG antibodies. Serum cotinine levels and environmental tobacco smoke (ETS exposure were determined for all participants. RESULTS: There was no significant difference in H. pylori infection between the children with chronic tonsillitis and children free of disease, but there was a significant difference in ETS between the two groups (P = 0.011. We next studied the association between ETS and chronic tonsillitis based on H. pylori infection status. In the patients with H. pylori infection, there was a significant difference in ETS distribution between the chronic tonsillitis and control groups (P = 0.022. Taking the participants without ETS as the reference, multivariate logistic regression analysis showed that those with high ETS had higher susceptibility to chronic tonsillitis (adjusted OR = 2.33; 95% CI: 1.67-3.25; adjusted P < 0.001. However, among those without H. pylori infection, ETS did not predispose towards chronic tonsillitis. CONCLUSION: Our findings suggest that tobacco exposure should be a putative mediator risk factor to chronic tonsillitis among children with H. pylori infection.

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

38 CFR 3.316 - Claims based on chronic effects of exposure to mustard gas and Lewisite.

Science.gov (United States)

2010-07-01

... effects of exposure to mustard gas and Lewisite. 3.316 Section 3.316 Pensions, Bonuses, and Veterans... Compensation Ratings and Evaluations; Service Connection § 3.316 Claims based on chronic effects of exposure to mustard gas and Lewisite. (a) Except as provided in paragraph (b) of this section, exposure to the...

Derived limits for occupational exposure to uranium mine and mill dusts in the air and on surfaces

International Nuclear Information System (INIS)

Carter, M.W.

1983-01-01

Limits are derived for the concentration of uranium mine and mill dusts in the air based on ICRP30 and assumptions regarding the isotopic make up of the dusts. From these limits using a resuspension factor, limits for surface contamination are derived. Calculations are presented of the dose to the basal layer of the skin from mine and mill dusts on the skin. From these calculations limits for skin contamination are derived. A calculation of a limit based on direct ingestion is also presented. Exposure limits for the public are not considered

Review of the chronic exposure pathways models in MACCS [MELCOR Accident Consequence Code System] and several other well-known probabilistic risk assessment models

International Nuclear Information System (INIS)

Tveten, U.

1990-06-01

The purpose of this report is to document the results of the work performed by the author in connection with the following task, performed for US Nuclear Regulatory Commission, (USNRC) Office of Nuclear Regulatory Research, Division of Systems Research: MACCS Chronic Exposure Pathway Models: Review the chronic exposure pathway models implemented in the MELCOR Accident Consequence Code System (MACCS) and compare those models to the chronic exposure pathway models implemented in similar codes developed in countries that are members of the OECD. The chronic exposures concerned are via: the terrestrial food pathways, the water pathways, the long-term groundshine pathway, and the inhalation of resuspended radionuclides pathway. The USNRC has indicated during discussions of the task that the major effort should be spent on the terrestrial food pathways. There is one chapter for each of the categories of chronic exposure pathways listed above

Mitochondrial ROS induced by chronic ethanol exposure promote hyper-activation of the NLRP3 inflammasome

Directory of Open Access Journals (Sweden)

Laura R. Hoyt

2017-08-01

Full Text Available Alcohol use disorders are common both in the United States and globally, and are associated with a variety of co-morbid, inflammation-linked diseases. The pathogenesis of many of these ailments are driven by the activation of the NLRP3 inflammasome, a multi-protein intracellular pattern recognition receptor complex that facilitates the cleavage and secretion of the pro-inflammatory cytokines IL-1β and IL-18. We hypothesized that protracted exposure of leukocytes to ethanol would amplify inflammasome activation, which would help to implicate mechanisms involved in diseases associated with both alcoholism and aberrant NLRP3 inflammasome activation. Here we show that long-term ethanol exposure of human peripheral blood mononuclear cells and a mouse macrophage cell line (J774 amplifies IL-1β secretion following stimulation with NLRP3 agonists, but not with AIM2 or NLRP1b agonists. The augmented NRLP3 activation was mediated by increases in iNOS expression and NO production, in conjunction with increases in mitochondrial membrane depolarization, oxygen consumption rate, and ROS generation in J774 cells chronically exposed to ethanol (CE cells, effects that could be inhibited by the iNOS inhibitor SEITU, the NO scavenger carboxy-PTIO, and the mitochondrial ROS scavenger MitoQ. Chronic ethanol exposure did not alter K+ efflux or Zn2+ homeostasis in CE cells, although it did result in a lower intracellular concentration of NAD+. Prolonged administration of acetaldehyde, the product of alcohol dehydrogenase (ADH mediated metabolism of ethanol, mimicked chronic ethanol exposure, whereas ADH inhibition prevented ethanol-induced IL-1β hypersecretion. Together, these results indicate that increases in iNOS and mitochondrial ROS production are critical for chronic ethanol-induced IL-1β hypersecretion, and that protracted exposure to the products of ethanol metabolism are probable mediators of NLRP3 inflammasome hyperactivation. Keywords: Inflammasome, IL

Atomic-scale Studies of Uranium Oxidation and Corrosion by Water Vapour.

Science.gov (United States)

Martin, T L; Coe, C; Bagot, P A J; Morrall, P; Smith, G D W; Scott, T; Moody, M P

2016-07-12

Understanding the corrosion of uranium is important for its safe, long-term storage. Uranium metal corrodes rapidly in air, but the exact mechanism remains subject to debate. Atom Probe Tomography was used to investigate the surface microstructure of metallic depleted uranium specimens following polishing and exposure to moist air. A complex, corrugated metal-oxide interface was observed, with approximately 60 at.% oxygen content within the oxide. Interestingly, a very thin (~5 nm) interfacial layer of uranium hydride was observed at the oxide-metal interface. Exposure to deuterated water vapour produced an equivalent deuteride signal at the metal-oxide interface, confirming the hydride as originating via the water vapour oxidation mechanism. Hydroxide ions were detected uniformly throughout the oxide, yet showed reduced prominence at the metal interface. These results support a proposed mechanism for the oxidation of uranium in water vapour environments where the transport of hydroxyl species and the formation of hydride are key to understanding the observed behaviour.

Atomic-scale Studies of Uranium Oxidation and Corrosion by Water Vapour

Science.gov (United States)

Martin, T. L.; Coe, C.; Bagot, P. A. J.; Morrall, P.; Smith, G. D. W.; Scott, T.; Moody, M. P.

2016-07-01

Understanding the corrosion of uranium is important for its safe, long-term storage. Uranium metal corrodes rapidly in air, but the exact mechanism remains subject to debate. Atom Probe Tomography was used to investigate the surface microstructure of metallic depleted uranium specimens following polishing and exposure to moist air. A complex, corrugated metal-oxide interface was observed, with approximately 60 at.% oxygen content within the oxide. Interestingly, a very thin (~5 nm) interfacial layer of uranium hydride was observed at the oxide-metal interface. Exposure to deuterated water vapour produced an equivalent deuteride signal at the metal-oxide interface, confirming the hydride as originating via the water vapour oxidation mechanism. Hydroxide ions were detected uniformly throughout the oxide, yet showed reduced prominence at the metal interface. These results support a proposed mechanism for the oxidation of uranium in water vapour environments where the transport of hydroxyl species and the formation of hydride are key to understanding the observed behaviour.

Chronic lead exposure induces cochlear oxidative stress and potentiates noise-induced hearing loss.

Science.gov (United States)

Jamesdaniel, Samson; Rosati, Rita; Westrick, Judy; Ruden, Douglas M

2018-08-01

Acquired hearing loss is caused by complex interactions of multiple environmental risk factors, such as elevated levels of lead and noise, which are prevalent in urban communities. This study delineates the mechanism underlying lead-induced auditory dysfunction and its potential interaction with noise exposure. Young-adult C57BL/6 mice were exposed to: 1) control conditions; 2) 2 mM lead acetate in drinking water for 28 days; 3) 90 dB broadband noise 2 h/day for two weeks; and 4) both lead and noise. Blood lead levels were measured by inductively coupled plasma mass spectrometry analysis (ICP-MS) lead-induced cochlear oxidative stress signaling was assessed using targeted gene arrays, and the hearing thresholds were assessed by recording auditory brainstem responses. Chronic lead exposure downregulated cochlear Sod1, Gpx1, and Gstk1, which encode critical antioxidant enzymes, and upregulated ApoE, Hspa1a, Ercc2, Prnp, Ccl5, and Sqstm1, which are indicative of cellular apoptosis. Isolated exposure to lead or noise induced 8-12 dB and 11-25 dB shifts in hearing thresholds, respectively. Combined exposure induced 18-30 dB shifts, which was significantly higher than that observed with isolated exposures. This study suggests that chronic exposure to lead induces cochlear oxidative stress and potentiates noise-induced hearing impairment, possibly through parallel pathways. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Renal dysfunction induced by long-term exposure to depleted uranium in rats

Energy Technology Data Exchange (ETDEWEB)

Zhu, Guoying; Xiang, Xiqiao; Chen, Xiao; Wang, Lihua; Hu, Heping; Weng, Shifang [Fudan University, Institute of Radiation Medicine, Shanghai (China)

2009-01-15

Depleted uranium (DU) is a kind of radioactive heavy metal which can enter into the body via inhalation (aerosols), ingestion (drinking and eating) and wounds (embedded), and causes chemical and/or radiation-induced toxicities. In this study, male Sprague Dawley rats were surgically implanted in gastrocnemius muscle with DU fragments at three dose levels (low-dose, medium-dose and high-dose), with biologically inert tantalum (Ta) fragments served as controls. At 1 day, 7 days, and 3, 6, and 12 months after implantation, the rats were euthanized and tissue samples were collected, and uranium levels were measured in a variety of tissues by inductively coupled plasma-mass spectrometry (ICP-MS) to analyze the dynamic changes and distribution of uranium in rats. Thereafter, at 3, 6 and 12 months after implantation, the rats were euthanized after the collection of 24 h urine, blood and kidney samples were collected for analysis of DU-induced renal histopathologic changes and renal dysfunction. It was observed that DU concentrations in all the DU implanted groups were higher than that in Ta control group, and DU concentrations in the kidney increased with the implanted times, peaked at the 90 days after implantation, with a high correlation to the implanted DU doses, and then began to decrease gradually and slowly, and the DU concentrations in kidney still maintained at a relatively high level even at the 360 days after implantation. Otherwise, chronic DU contamination could induce the pathological changes of renal glomeruli, tubules and mesenchyme, such as interstitial fibrosis, enlarged interstice of renal tubular epithelial cells, tumefactions and necrosis of epithelial cells, shrinkage and disappearance of cavity of Bowman's capsule. By TEM, it was shown that the basement membrane of glomerulus was incrassated, mitochondrial of kidney proximal tubule had visible tumefaction and became bigger, and the mitochondrial cristae became shorter and disorderly in

Renal dysfunction induced by long-term exposure to depleted uranium in rats

International Nuclear Information System (INIS)

Zhu, Guoying; Xiang, Xiqiao; Chen, Xiao; Wang, Lihua; Hu, Heping; Weng, Shifang

2009-01-01

Depleted uranium (DU) is a kind of radioactive heavy metal which can enter into the body via inhalation (aerosols), ingestion (drinking and eating) and wounds (embedded), and causes chemical and/or radiation-induced toxicities. In this study, male Sprague Dawley rats were surgically implanted in gastrocnemius muscle with DU fragments at three dose levels (low-dose, medium-dose and high-dose), with biologically inert tantalum (Ta) fragments served as controls. At 1 day, 7 days, and 3, 6, and 12 months after implantation, the rats were euthanized and tissue samples were collected, and uranium levels were measured in a variety of tissues by inductively coupled plasma-mass spectrometry (ICP-MS) to analyze the dynamic changes and distribution of uranium in rats. Thereafter, at 3, 6 and 12 months after implantation, the rats were euthanized after the collection of 24 h urine, blood and kidney samples were collected for analysis of DU-induced renal histopathologic changes and renal dysfunction. It was observed that DU concentrations in all the DU implanted groups were higher than that in Ta control group, and DU concentrations in the kidney increased with the implanted times, peaked at the 90 days after implantation, with a high correlation to the implanted DU doses, and then began to decrease gradually and slowly, and the DU concentrations in kidney still maintained at a relatively high level even at the 360 days after implantation. Otherwise, chronic DU contamination could induce the pathological changes of renal glomeruli, tubules and mesenchyme, such as interstitial fibrosis, enlarged interstice of renal tubular epithelial cells, tumefactions and necrosis of epithelial cells, shrinkage and disappearance of cavity of Bowman's capsule. By TEM, it was shown that the basement membrane of glomerulus was incrassated, mitochondrial of kidney proximal tubule had visible tumefaction and became bigger, and the mitochondrial cristae became shorter and disorderly in alignment

Bilateral Vestibular Dysfunction Associated With Chronic Exposure to Military Jet Propellant Type-Eight Jet Fuel

Directory of Open Access Journals (Sweden)

Terry D. Fife

2018-05-01

Full Text Available We describe three patients diagnosed with bilateral vestibular dysfunction associated with the jet propellant type-eight (JP-8 fuel exposure. Chronic exposure to aromatic and aliphatic hydrocarbons, which are the main constituents of JP-8 military aircraft jet fuel, occurred over 3–5 years’ duration while working on or near the flight line. Exposure to toxic hydrocarbons was substantiated by the presence of JP-8 metabolite n-hexane in the blood of one of the cases. The presenting symptoms were dizziness, headache, fatigue, and imbalance. Rotational chair testing confirmed bilateral vestibular dysfunction in all the three patients. Vestibular function improved over time once the exposure was removed. Bilateral vestibular dysfunction has been associated with hydrocarbon exposure in humans, but only recently has emphasis been placed specifically on the detrimental effects of JP-8 jet fuel and its numerous hydrocarbon constituents. Data are limited on the mechanism of JP-8-induced vestibular dysfunction or ototoxicity. Early recognition of JP-8 toxicity risk, cessation of exposure, and customized vestibular therapy offer the best chance for improved balance. Bilateral vestibular impairment is under-recognized in those chronically exposed to all forms of jet fuel.

Striatal proteomic analysis suggests that first L-dopa dose equates to chronic exposure.

Directory of Open Access Journals (Sweden)

Birger Scholz

Full Text Available L-3,4-dihydroxypheylalanine (L-dopa-induced dyskinesia represent a debilitating complication of therapy for Parkinson's disease (PD that result from a progressive sensitization through repeated L-dopa exposures. The MPTP macaque model was used to study the proteome in dopamine-depleted striatum with and without subsequent acute and chronic L-dopa treatment using two-dimensional difference in-gel electrophoresis (2D-DIGE and mass spectrometry. The present data suggest that the dopamine-depleted striatum is so sensitive to de novo L-dopa treatment that the first ever administration alone would be able (i to induce rapid post-translational modification-based proteomic changes that are specific to this first exposure and (ii, possibly, lead to irreversible protein level changes that would be not further modified by chronic L-dopa treatment. The apparent equivalence between first and chronic L-dopa administration suggests that priming would be the direct consequence of dopamine loss, the first L-dopa administrations only exacerbating the sensitization process but not inducing it.

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

Chronic exposure to environmental levels of tribromophenol impairs zebrafish reproduction

International Nuclear Information System (INIS)

Deng Jun; Liu Chunsheng; Yu Liqin; Zhou Bingsheng

2010-01-01

Tribromophenol (2,4,6-TBP) is ubiquitously found in aquatic environments and biota. In this study, we exposed zebrafish embryos (F 0 ; 2'''' days post-fertilization, dpf) to environmental concentration (0.3 μg/L) and a higher concentration (3.0 μg/L) of TBP and assessed the impact of chronic exposure (120 dpf) on reproduction. TBP exposure did not cause a significant increase in the malformation and reduction in the survival in the F 0 -generation fish. After TBP exposure, the plasma testosterone and estradiol levels significantly increased in males and decreased in females. The transcription of steroidogenic genes (3β-HSD, 17β-HSD, CYP17, CYP19A, CYP19B) was significantly upregulated in the brain and testes in males and downregulated in the brain and ovary in females. TBP exposure significantly downregulated and upregulated the expression of VTG in the liver of female and male fish, respectively. Meanwhile, TBP exposure altered the sex ratio toward a male-dominant state. The F 1 -generation larvae exhibited increased malformation, reduced survival, and retarded growth, suggesting that TBP in the aquatic environment has significant adverse effects on fish population.

Properties, use and health effects of depleted uranium (DU): a general overview

International Nuclear Information System (INIS)

Bleise, A.; Danesi, P.R.; Burkart, W.

2003-01-01

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 and recently as the Balkan Syndrome. This led to renewed efforts to assess the environmental consequences and the health impact of the use of DU. 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 chemotoxicity, but its radiotoxicity is 60% higher. Due to the 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. Depending on aerosol speciation, inhalation may lead to a protracted exposure of the lung and other organs. After deposition on the ground, resuspension can take place if the DU containing particle size is sufficiently small. However, transfer to drinking water or locally produced food has little potential to lead to significant exposures to DU. Since poor solubility of uranium compounds and lack of information on speciation precludes the use of radioecological models for exposure assessment, biomonitoring has to be used for assessing exposed persons. Urine, feces, hair and nails record recent exposures to DU. 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

Properties, use and health effects of depleted uranium (DU): a general overview

Energy Technology Data Exchange (ETDEWEB)

Bleise, A.; Danesi, P.R.; Burkart, W. E-mail: w.burkart@iaea.org

2003-07-01

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 and recently as the Balkan Syndrome. This led to renewed efforts to assess the environmental consequences and the health impact of the use of DU. 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 chemotoxicity, but its radiotoxicity is 60% higher. Due to the 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. Depending on aerosol speciation, inhalation may lead to a protracted exposure of the lung and other organs. After deposition on the ground, resuspension can take place if the DU containing particle size is sufficiently small. However, transfer to drinking water or locally produced food has little potential to lead to significant exposures to DU. Since poor solubility of uranium compounds and lack of information on speciation precludes the use of radioecological models for exposure assessment, biomonitoring has to be used for assessing exposed persons. Urine, feces, hair and nails record recent exposures to DU. 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.

Properties, use and health effects of depleted uranium (DU): a general overview.

Science.gov (United States)

Bleise, A; Danesi, P R; Burkart, W

2003-01-01

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 and recently as the Balkan Syndrome. This led to renewed efforts to assess the environmental consequences and the health impact of the use of DU. 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 chemotoxicity, but its radiotoxicity is 60% higher. Due to the 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. Depending on aerosol speciation, inhalation may lead to a protracted exposure of the lung and other organs. After deposition on the ground, resuspension can take place if the DU containing particle size is sufficiently small. However, transfer to drinking water or locally produced food has little potential to lead to significant exposures to DU. Since poor solubility of uranium compounds and lack of information on speciation precludes the use of radioecological models for exposure assessment, biomonitoring has to be used for assessing exposed persons. Urine, feces, hair and nails record recent exposures to DU. 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.

Persistent effects of prior chronic exposure to corticosterone on reward-related learning and motivation in rodents.

Science.gov (United States)

Olausson, Peter; Kiraly, Drew D; Gourley, Shannon L; Taylor, Jane R

2013-02-01

Repeated or prolonged exposure to stress has profound effects on a wide spectrum of behavioral and neurobiological processes and has been associated with the pathophysiology of depression. The multifaceted nature of this disorder includes despair, anhedonia, diminished motivation, and disrupted cognition, and it has been proposed that depression is also associated with reduced reward-motivated learning. We have previously reported that prior chronic corticosterone exposure to mice produces a lasting depressive-like state that can be reversed by chronic antidepressant treatment. In the present study, we tested the effects of prior chronic exposure to corticosterone (50 μg/ml) administered to rats or to mice in drinking water for 14 days followed by dose-tapering over 9 days. The exposure to corticosterone produced lasting deficits in the acquisition of reward-related learning tested on a food-motivated instrumental task conducted 10-20 days after the last day of full dose corticosterone exposure. Rats exposed to corticosterone also displayed reduced responding on a progressive ratio schedule of reinforcement when tested on day 21 after exposure. Amitriptyline (200 mg/ml in drinking water) exposure for 14 days to mice produced the opposite effect, enhancing food-motivated instrumental acquisition and performance. Repeated treatment with amitriptyline (5 mg/kg, intraperitoneally; bid) subsequent to corticosterone exposure also prevented the corticosterone-induced deficits in rats. These results are consistent with aberrant reward-related learning and motivational processes in depressive states and provide new evidence that stress-induced neuroadaptive alterations in cortico-limbic-striatal brain circuits involved in learning and motivation may play a critical role in aspects of mood disorders.

Induction of glutathione synthesis in human hepatocytes by acute and chronic arsenic exposure: Differential roles of mitogen-activated protein kinases

International Nuclear Information System (INIS)

Hou, Yongyong; Wang, Yi; Wang, Huihui; Xu, Yuanyuan

2014-01-01

Highlights: • Arsenic exposure increased intracellular levels of glutathione. • Mitogen-activated protein kinases were involved in glutathione homeostasis. • ERK contributed to glutathione synthesis during acute arsenic exposure. • Glutathione synthesis was regulated by p38 at least in part independent of NRF2 during chronic arsenic exposure. - Abstract: Glutathione (GSH) is a vital component of antioxidant defense which protects cells from toxic insults. Previously we found intracellular GSH was involved in cell resistance against arsenic-induced cytotoxicity. However, molecular mechanisms of GSH homeostasis during arsenic exposure are largely undefined. Here, we investigated roles of mitogen-activated protein kinases (MAPKs) in GSH synthesis pathway with two arsenic exposure strategies by using Chang human hepatocytes. In one strategy, acute arsenic exposure (20 μM, 24 h) was applied, as MAPK signaling is generally considered to be transient. In the other one, chronic arsenic exposure (500 nM, 20 weeks) was applied, which mimicked the general human exposure to arsenic. We found that acute arsenic exposure activated extracellular signal-regulated 1/2 kinases (ERK1/2) and c-Jun N-terminal kinase (JNK) in parallel with increased transcription and nuclear translocation of factor-erythroid 2-related factor 2 (NRF2) and enhanced expression of γ-glutamyl cysteine ligase catalytic subunit (GCLC), resulting in elevated intracellular GSH levels. Specific ERK inhibitor abolished arsenic-induced NRF2 nuclear translocation and GSH synthesis. During chronic arsenic exposure which induced a malignant cellular phenotype, continuous p38 activation and NRF2 nuclear translocation were observed with enhanced GSH synthesis. Specific p38 inhibitor attenuated arsenic-enhanced GSH synthesis without changing NRF2 nuclear translocation. Taken together, our results indicate MAPK pathways play an important role in cellular GSH homeostasis in response to arsenic. However, the

Internal dosimetry and radiotoxicity of long-lived uranium isotopes

International Nuclear Information System (INIS)

Jacobi, W.

1980-03-01

The dose to relevant tissues and the effective dose equivalent by ingestion and inhalation of uranium compounds are evaluated on the basis of the new metabolic and dosimetric models recommended by ICRP. Applying these dose factors annual limits for intake of these compounds by workers are derived. Finally the natural uranium exposure of the population is described. From the measured natural U-content of body tissues dose factors for the dietary intake of uranium can be estimated. (orig.) [de

Chronic Exposure to Particulate Nickel Induces Neoplastic Transformation in Human Lung Epithelial Cells

Directory of Open Access Journals (Sweden)

Amie L. Holmes

2013-11-01

Full Text Available Nickel is a well-known human lung carcinogen with the particulate form being the most potent; however, the carcinogenic mechanism remains largely unknown. Few studies have investigated the genotoxicity and carcinogenicity of nickel in its target cell, human bronchial epithelial cells. Thus, the goal of this study was to investigate the effects of particulate nickel in human lung epithelial cells. We found that nickel subsulfide induced concentration- and time-dependent increases in both cytotoxicity and genotoxicity in human lung epithelial cells (BEP2D. Chronic exposure to nickel subsulfide readily induced cellular transformation, inducing 2.55, 2.9 and 2.35 foci per dish after exposure to 1, 2.5 and 5 μg/cm2 nickel subsulfide, respectively. Sixty-one, 100 and 70 percent of the foci isolated from 1, 2.5, and 5 μg/cm2 nickel subsulfide treatments formed colonies in soft agar and the degree of soft agar colony growth increased in a concentration-dependent manner. Thus, chronic exposure to particulate nickel induces genotoxicity and cellular transformation in human lung epithelial cells.

Derivation of soil screening thresholds to protect chisel-toothed kangaroo rat from uranium mine waste in northern Arizona

Science.gov (United States)

Hinck, Jo E.; Linder, Greg L.; Otton, James K.; Finger, Susan E.; Little, Edward E.; Tillitt, Donald E.

2013-01-01

Chemical data from soil and weathered waste material samples collected from five uranium mines north of the Grand Canyon (three reclaimed, one mined but not reclaimed, and one never mined) were used in a screening-level risk analysis for the Arizona chisel-toothed kangaroo rat (Dipodomys microps leucotis); risks from radiation exposure were not evaluated. Dietary toxicity reference values were used to estimate soil-screening thresholds presenting risk to kangaroo rats. Sensitivity analyses indicated that body weight critically affected outcomes of exposed-dose calculations; juvenile kangaroo rats were more sensitive to the inorganic constituent toxicities than adult kangaroo rats. Species-specific soil-screening thresholds were derived for arsenic (137 mg/kg), cadmium (16 mg/kg), copper (1,461 mg/kg), lead (1,143 mg/kg), nickel (771 mg/kg), thallium (1.3 mg/kg), uranium (1,513 mg/kg), and zinc (731 mg/kg) using toxicity reference values that incorporate expected chronic field exposures. Inorganic contaminants in soils within and near the mine areas generally posed minimal risk to kangaroo rats. Most exceedances of soil thresholds were for arsenic and thallium and were associated with weathered mine wastes.

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)

Reference values and their application to the monitoring of occupational exposure to natural uranium compounds

International Nuclear Information System (INIS)

1986-09-01

Natural uranium compounds, which enter the oxide fuel cycle offer physico-chemical characteristics dependent on their structure and their production process. These characteristics govern their biological behaviour and the degree of their radioactive and chemical toxicity. The monitoring of workers occupationnally exposed to these compounds is carried out by bioassays; in order to get the best interpretation, the resulting data must be compared to reference values. These values must be closely related to the type of contaminant and the real exposure conditions. In this report, the occupational medicine services working group has examined the possibilities of obtaining such reference values and suggests recommendations and operational values covering most situations found in routine monitoring [fr

Behavioral and Physiological Responses to Nicotine Patch Administration Among Nonsmokers Based on Acute and Chronic Secondhand Tobacco Smoke Exposure.

Science.gov (United States)

Okoli, Chizimuzo; Kodet, Jonathan; Robertson, Heather

2016-01-01

Despite the large amount that is known about the physical health effects of secondhand tobacco smoke (SHS) exposure, little is known about the behavioral health effects. Nicotine, the principle psychoactive substance in SHS, elicits subjective mood and physiological responses in nonsmokers. However, no studies have examined the subjective mood or physiological responses to nicotine in nonsmokers while accounting for prior chronic or acute SHS exposure. A 7-mg nicotine patch was administered to 17 adult nonsmokers for 2 hr. Main outcome measures obtained at ½ hr, 1 hr, and 2 hr were subjective behavioral drug effects (based on eleven 10-cm Visual Analog Scales [VASs]) and the physiological measures of heart rate, blood pressure, and serum nicotine levels. Analysis of outcome data was based on participants' chronic (using hair nicotine) or acute (using saliva cotinine) SHS exposure. Greater chronic SHS exposure was negatively associated with pleasurable responses to nicotine administration ("drug feels good" score at 2-hr time point, Spearman's ρ = -.65, p < .004), whereas greater acute SHS exposure was associated with positive responses ("like feeling of drug" score at 2-hr time point, Spearman's ρ = .63, p < .01). There were no associations between chronic or acute exposure and physiological changes in response to nicotine administration. The findings of this study may be useful in providing preliminary empirical data for future explorations of the mechanism whereby SHS exposure can influence behavioral outcomes in nonsmokers. Such studies can inform future interventions to reduce the physical and behavioral health risks associated with SHS exposure. © The Author(s) 2015.

Existing Regulatory Approaches to Reducing Exposures to Chemical- and Product-Based Risk and Their Applicability to Diet-Related Chronic Disease.

Science.gov (United States)

Cohen, Deborah A; Knopman, Debra S

2018-04-17

We aimed to identify and categorize the types of policies that have been adopted to protect Americans from harmful exposures that could also be relevant for addressing diet-related chronic diseases. This article examines and categorizes the rationales behind government regulation. Our interest in the historical analysis is to inform judgments about how best to address newly emergent risks involving diet-related chronic disease within existing regulatory and information-based frameworks. We assessed exemplars of regulation with respect to harmful exposures from air, water, and food, as well as regulations that are intended to modify voluntary behaviors. Following the comparative analysis, we explored how exposures that lead to diet-related chronic diseases among the general population fit within models of regulation adopted for other comparable risks. We identified five rationales and five approaches that protect people from harmful exposures. Reasons for regulation include: protection from involuntary exposure to risk, high risk of death or chronic illness, ubiquity of risk, counteraction to limit compulsive behaviors, and promotion of population health. Regulatory approaches include: mandatory limits on use, mandatory limits on exposure, mandatory controls on quality, mandatory labeling, and voluntary guidance. In contrast to the use of mandates, the prevention of diet-related chronic diseases thus far has largely relied on information-only approaches and voluntary adoption of guidelines. There is ample precedent for mandatory regulatory approaches that could address harms related to exposure to unhealthy diets, but several barriers to action would need to be overcome. © 2018 Society for Risk Analysis.

Radioactive wastes of uranium mining and milling: Radiological consequences for human population and natural environment

International Nuclear Information System (INIS)

Sazykina, T.G.; Kryshev, I.I.

2002-01-01

The sources of wastes and levels of radioactive contamination are considered in the areas of uranium ore mining and milling. Assessments of doses to the population are made using the methodology of multiple sources and pathways of exposure, including calculations of inhalation dose and doses from consumption of contaminated agricultural and natural products, as well as external exposure from the radioactive cloud and soil. On the local (0-100 km) spatial scale, the dose from uranium mining and processing is, on average, about 0.7 man Sv (GWa) -1 . The most significant pathway of the population exposure is inhalation of radon. The impact of uranium ore mining and processing on natural flora and fauna is determined by specific characteristics of the production at uranium mining enterprises and has both radiation and non-radiation components. The estimates of external and internal exposures to the natural biota in the vicinity of hydro-metallurgical works and tailing dumps are presented. (author)

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

Hematological and biochemical effects of chronic CO exposure on the Japanese quail

Energy Technology Data Exchange (ETDEWEB)

Jaeger, J.J.; McGrath, J.J.

1975-01-01

Japanese Quail were exposed to a concentration of 300 to 350 ppm CO to maintain an equilibrium carboxyhemoglobin concentration of 30% for a period of 4 weeks. Compared to a control group of birds maintained in an identical chamber, the CO-exposed quail demonstrated increases in hematocrit ratio and hemoglobin concentration. At the end of the exposure period, the CO-exposed quail had significantly larger plasma glucose concentrations than the control birds. Cardiac and skeletal muscle carbohydrate stores were not affected by chronic CO exposure.

Chronic exposure of zinc oxide nanoparticles causes deviant phenotype in Drosophila melanogaster

Energy Technology Data Exchange (ETDEWEB)

Anand, Avnika Singh; Prasad, Dipti N.; Singh, Shashi Bala; Kohli, Ekta, E-mail: ektakohli@hotmail.com

2017-04-05

Zinc oxide nanoparticles (ZnO NPs) are commonly used nanomaterials (NMs) with versatile applications from high-end technologies to household products. This pervasive utilisation has brought human in the close interface with nanoparticles (NPs), hence questioning their safety prior to usage is a must. In this study, we have assessed the effects of chronic exposure to ZnO NPs (<50 nm) on the model organism Drosophila melanogaster. Potential toxic effects were studied by evaluating longevity, climbing ability, oxidative stress and DNA fragmentation. Ensuing exposure, the F0 (parent), F1, F2, F3 and F4 generation flies were screened for the aberrant phenotype. Flies exposed to ZnO NPs showed distinctive phenotypic changes, like deformed segmented thorax and single or deformed wing, which were transmitted to the offspring’s in subsequent generations. The unique abnormal phenotype is evident of chronic toxicity induced by ZnO NPs, although appalling, it strongly emphasize the importance to understand NPs toxicity for safer use.

Acute but not chronic ethanol exposure impairs retinol oxidation in the small and large intestine of the rat

DEFF Research Database (Denmark)

Parlesak, Alexandr; Ellendt, K.; Lindros, K.

2005-01-01

BACKGROUND AND AIM: Ethanol has been shown to inhibit retinol oxidation at the level of alcohol dehydrogenase in liver and colon but not previously in the small intestine. In the present study we investigated how chronic alcohol feeding and acute ethanol exposure affects retinol dehydrogenase...... higher, respectively). While chronic alcohol feeding did not affect these parameters, acute ethanol exposure reduced V(max) and V(max)/K(m) dose-dependently (p

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

Radiological health aspects of uranium milling

International Nuclear Information System (INIS)

Fisher, D.R.; Stoetzel, G.A.

1983-05-01

This report describes the operation of conventional and unconventional uranium milling processes, the potential for occupational exposure to ionizing radiation at the mill, methods for radiological safety, methods of evaluating occupational radiation exposures, and current government regulations for protecting workers and ensuring that standards for radiation protection are adhered to. In addition, a survey of current radiological health practices is summarized

Radiological health aspects of uranium milling

Energy Technology Data Exchange (ETDEWEB)

Fisher, D.R.; Stoetzel, G.A.

1983-05-01

This report describes the operation of conventional and unconventional uranium milling processes, the potential for occupational exposure to ionizing radiation at the mill, methods for radiological safety, methods of evaluating occupational radiation exposures, and current government regulations for protecting workers and ensuring that standards for radiation protection are adhered to. In addition, a survey of current radiological health practices is summarized.

MBST-exposure opportunities as a monotherapy of chronic dorsalgia

Directory of Open Access Journals (Sweden)

Levchenko КК

2017-09-01

Full Text Available The aim: to analyze the clinical effect of MBST-exposure monotherapy, a magnetic resonance method, on the pain syndrome caused by degenerative dystrophic changes of vertebral column structures. Material and Methods. 132 patients both male and female with cervical and lumbar dorsopathy were enrolled into the study. Treatment course included 9 sessions of 60 min. daily. MRI-results of corresponding spine regions and visual analogue pain intensity scale were used as assessment tools for treatment efficiency before, immediately after, 3, 6 and 12 months after MBST-treatment. Results. The objective results of structural transformation of pathological formations in vertebral motional segments correlated with significant decrease of pain syndrome at all stages of control tests. Conclusion. MBST-exposure is an effective method of non-invasive, notouch monotherapy for patients with chronic dorsalgia caused by degenerative dorsopathy.

Hereditary effects of low and chronic radiation exposure: a case-control study of mental retardation and cleft lip/palate in the monazite bearing coastal areas of Southern Kerala

International Nuclear Information System (INIS)

Koya, P.K.M.; Cheriyan, V.D.; Chougaonkar, M.P.; Mayya, Y.S.; Jojo, P.J.; Predeep, P.; Seshadri, M.

2010-01-01

The high level natural radiation (HLNR) areas of Kerala in the south west coast of Kerala is suitable for direct human studies to assess the genetic and teratogenic effect of low and chronic radiation exposures. The radiation level in the region (about 55 km long and 0.5 km wide belt) range from ≤1.0 mGy to 45.0 mGy per year and is due to natural deposit of monazite sand containing Thorium (8-10%), Uranium (0.3%) and corresponding decay products. A population based case-control study was carried out in the area to assess the role, if any, of HLNR as a causative factor in the etiology of two relatively frequent and easily identifiable congenital malformations, viz., mental retardation (MR) and cleft lip/palate (CLP). Findings from the study are discussed in this paper

Evaluation of a Po-210 bioassay as an index of the exposure of uranium mine workers in Japan to radon daughters

International Nuclear Information System (INIS)

Okabayashi, Hiroyuki; Suzuki, Masashi; Hongo, Shozo; Watanabe, Seiki.

1975-01-01

As an indicator nuclide for inhalation exposure of mine workders to Rn daughters in a Japanses uranium mine, 210 Po urinalyses of the workers and surveys of some environmental factors were conducted. An estimation study of concentrations of Rn daughters in a mine, indicated that about 800-50 pCi of 210 Po could have been accumulated in each miner's body. However, according to the results of urinalyses performed several times in 5 years, a statistical difference in the quantity of 210 Po in urine among miners and non-mining workers there was not clearly identified. Investigations of 210 Po concentrations in the mine's air, water, foods (of about 30 kinds) and cigarets, and investigations of feces-urine 210 Po ratios in humans revealed that these factors would greatly affect the metabolism and 210 Po excretion of the workers. In particular, some marine foods in Japan contained a great amount of 210 Po (several hundreds times that of other foods) and cigarets showed 0.3-0.8 pCi of 210 Po per gramme. Smokers definitely excreted more 210 Po in urine than non-smokers. Feces-urine ratios ranged between 5.2-42.9 in one human subject. Therefore, it can be concluded that 210 Po would not be a good indicator for human exposure to Rn daughters, unless great care is taken regarding the eating and smoking habits of mine workers, as well as the exposure conditions in the uranium mine. (Evans, J.)

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

Does chronic occupational exposure to volatile anesthetic agents influence the rate of neutrophil apoptosis?

LENUS (Irish Health Repository)

Goto, Y

2012-02-03

PURPOSE: The purpose of this preliminary investigation was to determine whether the rate of neutrophil apoptosis in health care workers is influenced by exposure to volatile anesthetic agents. METHODS: Percentage neutrophil apoptosis (Annexin-V FITC assay) was measured in health care workers (n = 20) and unexposed volunteers (n = 10). For the health care workers, time weighted personal exposure monitoring to N2O, sevoflurane and isoflurane was carried out. RESULTS: The sevoflurane and isoflurane concentrations to which health care workers were exposed were less than recommended levels in all 20 cases. Percent apoptosis was less at 24 (but not at one and 12) hr culture in health care workers [50.5 (9.7)%; P = 0.008] than in unexposed volunteers [57.3 (5.1)%]. CONCLUSION: Inhibition of neutrophil apoptosis at 24 hr culture was demonstrated in health care workers chronically exposed to volatile anesthetic agents. Exposure was well below recommended levels in the both scavenged and unscavenged work areas in which the study was carried out. Further study is required to assess the effect of greater degrees of chronic exposure to volatile anesthetic agents on neutrophil apoptosis.

Determination of uranium in urine samples for workers in the phosphoric acid purification using fluorimetry technique

International Nuclear Information System (INIS)

Kharita, M. H.; Sakhita, Kh.; Aldalal, Z.

2003-10-01

There is probability of exposure to uranium for workers in the phosphoric acid purification (internal exposure) by inhalation, and the deposition of this uranium in organs and tissues, and the consequence excreation out of the body by perspiration or urine. This study focuses on the determination of uranium in urine samples of workers. All results seem to be under the detection limit of the method, therefore no routine monitoring is required. (author)

Long-term consequences of chronic fluoxetine exposure on the expression of myelination-related genes in the rat hippocampus

Science.gov (United States)

Kroeze, Y; Peeters, D; Boulle, F; van den Hove, D L A; van Bokhoven, H; Zhou, H; Homberg, J R

2015-01-01

The selective serotonin reuptake inhibitor (SSRI) fluoxetine is widely prescribed for the treatment of symptoms related to a variety of psychiatric disorders. After chronic SSRI treatment, some symptoms remediate on the long term, but the underlying mechanisms are not yet well understood. Here we studied the long-term consequences (40 days after treatment) of chronic fluoxetine exposure on genome-wide gene expression. During the treatment period, we measured body weight; and 1 week after treatment, cessation behavior in an SSRI-sensitive anxiety test was assessed. Gene expression was assessed in hippocampal tissue of adult rats using transcriptome analysis and several differentially expressed genes were validated in independent samples. Gene ontology analysis showed that upregulated genes induced by chronic fluoxetine exposure were significantly enriched for genes involved in myelination. We also investigated the expression of myelination-related genes in adult rats exposed to fluoxetine at early life and found two myelination-related genes (Transferrin (Tf) and Ciliary neurotrophic factor (Cntf)) that were downregulated by chronic fluoxetine exposure. Cntf, a neurotrophic factor involved in myelination, showed regulation in opposite direction in the adult versus neonatally fluoxetine-exposed groups. Expression of myelination-related genes correlated negatively with anxiety-like behavior in both adult and neonatally fluoxetine-exposed rats. In conclusion, our data reveal that chronic fluoxetine exposure causes on the long-term changes in expression of genes involved in myelination, a process that shapes brain connectivity and contributes to symptoms of psychiatric disorders. PMID:26393488

Radiation hazard surveillance in spanish uranium mines

International Nuclear Information System (INIS)

Iranzo, E.; Liarte, J.

1963-01-01

The regulations applied in the uranium mines which belong to the Junta de Energia Nuclear to control the radioactive hazards, and to get the personal protection avoiding overexposures in the external radiation and inhalation of radioactive dust and gases are given. The Radon daughters concentration in the atmosphere of Avery one of the mines and the external radiation exposure and uranium excretion in urine of the miners during 1962 are specified. (Author) 9 refs

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

Assessment of the solubility of thorium and uranium from black sand of Camargue in both simulated lung and gut fluids for dose calculation after internal exposure

Energy Technology Data Exchange (ETDEWEB)

Frelon, S.; Chazel, V.; Tourlonias, E.; Paquet, F. [IRSN/ DRPH/ SRBE, LRTOX, BP 166, 26702 Pierrelatte Cedex (France); Blanchardon, E. [IRSN/ DRPH/ SDI, LEDI, BP 17, 92262 Fontenay Aux Roses Cedex (France); Bouisset, P. [IRSN/ DEI/ STEME, LMRE, Bois des rames, 91400 Orsay (France); Pourcelot, L. [IRSN/ DEI/ SESURE, LERCM, BP3, 13 115 St Paul lez Durance Cedex (France)

2006-07-01

In the south of France, some beaches of Camargue present a high rate of natural radioactivity due to thorium and uranium from zircon and apatite heavy minerals present in the so-called black sand. These radionuclides may lead to internal exposure consecutive to inhalation or ingestion of this sand. The accurate assessment of radiological risk after internal exposure of public frequenting these beaches requires some information on the human bioavailability of U and Th from the sand. Both routes of intake were studied in this work and the consecutive dose delivered was calculated under two different scenarios for each type of exposure. As far as inhalation is concerned, the first important conclusion is that the inhalable fraction, i.e. particles with aerodynamic diameters below 50 {mu}m, was tiny (0.002%) in this sample of sand. Moreover in vitro assays of solubility were performed for this fraction and showed that U and Th as well as their progeny presented moderate solubility. Then effective doses under several scenarios were calculated and seem to demonstrate a very poor risk of exposure after inhalation. Indeed, a dose of 1 mSv would be received by a babies after inhalation of about 40 Kg of sand, that is impossible, whereas a more realistic scenario of chronic exposure only reached 31 {mu} Sv. In case of ingestion, the solubility of Th and U in the gastrointestinal fluids was found to be very low with a maximum solubility of 0.5% of the initial mass of radioelement in the sample of sand. Then the worst hypothesis studied yields an effective dose of 0.018 mSv./(g-swallowed sand) that is roughly 50 times less than the legal annual dose limit for members of the public. as a conclusion, the possible internal dose after exposure by inhalation or ingestion of black sand of Camargue seems to be very low under the conditions of this study. (N.C.)

Assessment of the solubility of thorium and uranium from black sand of Camargue in both simulated lung and gut fluids for dose calculation after internal exposure

International Nuclear Information System (INIS)

Frelon, S.; Chazel, V.; Tourlonias, E.; Paquet, F.; Blanchardon, E.; Bouisset, P.; Pourcelot, L.

2006-01-01

In the south of France, some beaches of Camargue present a high rate of natural radioactivity due to thorium and uranium from zircon and apatite heavy minerals present in the so-called black sand. These radionuclides may lead to internal exposure consecutive to inhalation or ingestion of this sand. The accurate assessment of radiological risk after internal exposure of public frequenting these beaches requires some information on the human bioavailability of U and Th from the sand. Both routes of intake were studied in this work and the consecutive dose delivered was calculated under two different scenarios for each type of exposure. As far as inhalation is concerned, the first important conclusion is that the inhalable fraction, i.e. particles with aerodynamic diameters below 50 μm, was tiny (0.002%) in this sample of sand. Moreover in vitro assays of solubility were performed for this fraction and showed that U and Th as well as their progeny presented moderate solubility. Then effective doses under several scenarios were calculated and seem to demonstrate a very poor risk of exposure after inhalation. Indeed, a dose of 1 mSv would be received by a babies after inhalation of about 40 Kg of sand, that is impossible, whereas a more realistic scenario of chronic exposure only reached 31 μ Sv. In case of ingestion, the solubility of Th and U in the gastrointestinal fluids was found to be very low with a maximum solubility of 0.5% of the initial mass of radioelement in the sample of sand. Then the worst hypothesis studied yields an effective dose of 0.018 mSv./(g-swallowed sand) that is roughly 50 times less than the legal annual dose limit for members of the public. as a conclusion, the possible internal dose after exposure by inhalation or ingestion of black sand of Camargue seems to be very low under the conditions of this study. (N.C.)

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

Toxicity of a binary mixture on Daphnia magna: biological effects of uranium and selenium isolated and in mixture

International Nuclear Information System (INIS)

Zeman, F.

2008-10-01

Among the multiple substances that affect freshwater ecosystems, uranium and selenium are two pollutants found worldwide in the environment, alone and in mixture. The aim of this thesis work was to investigate the effect of uranium and selenium mixture on daphnia (Daphnia magna). Studying effects of a mixture requires the assessment of the effect of single substances. Thus, the first experiments were performed on single substance. Acute toxicity data were obtained: EC 50 48h = 0, 39±0, 04 mg.L -1 for uranium and EC 50 48h 1, 86±0, 85 mg.L -1 for selenium. Chronic effects were also studied. Data on fecundity showed an EC 10 reproduction of 14±7 μg. L -1 for uranium and of 215±25 μg. L -1 for selenium. Uranium-selenium mixture toxicity experiments were performed and revealed an antagonistic effect. This study further demonstrates the importance of taking into consideration different elements in binary mixture studies such as the choice of reference models (concentration addition or independent action), statistical method, time exposure and endpoints. Using integrated parameters like energy budget was shown to be an interesting way to better understand interactions. An approach including calculation of chemical speciation in the medium and bioaccumulation measurements in the organism permits assumptions to be made on the nature of possible interactions between mixture components (toxico-dynamic et toxico-kinetic interactions). (author)

Chemical toxicity and radioactivity of depleted uranium: The evidence from in vivo and in vitro studies.

Science.gov (United States)

Asic, Adna; Kurtovic-Kozaric, Amina; Besic, Larisa; Mehinovic, Lejla; Hasic, Azra; Kozaric, Mirza; Hukic, Mirsada; Marjanovic, Damir

2017-07-01

The main aim of this review is to summarize and discuss the current state of knowledge on chemical toxicity and radioactivity of depleted uranium (DU) and their effect on living systems and cell lines. This was done by presenting a summary of previous investigations conducted on different mammalian body systems and cell cultures in terms of potential changes caused by either chemical toxicity or radioactivity of DU. In addition, the authors aimed to point out the limitations of those studies and possible future directions. The majority of both in vitro and in vivo studies performed using animal models regarding possible effects caused by acute or chronic DU exposure has been reviewed. Furthermore, exposure time and dose, DU particle solubility, and uranium isotopes as factors affecting the extent of DU effects have been discussed. Special attention has been dedicated to chromosomal aberrations, DNA damage and DNA breaks, as well as micronuclei formation and epigenetic changes, as DU has recently been considered a possible causative factor of all these processes. Therefore, this approach might represent a novel area of study of DU-related irradiation effects on health. Since different studies offer contradictory results, the main aim of this review is to summarize and briefly discuss previously obtained results in order to identify the current opinion on DU toxicity and radioactivity effects in relation to exposure type and duration, as well as DU properties. Copyright © 2017 Elsevier Inc. All rights reserved.

Welding fume exposure and chronic obstructive pulmonary disease in welders.

Science.gov (United States)

Koh, D-H; Kim, J-I; Kim, K-H; Yoo, S-W

2015-01-01

Occupational exposure is estimated to contribute 15% to the burden of chronic obstructive pulmonary disease (COPD). Welding fumes are suspected to accelerate the decline of lung function and development of COPD. To examine the relationship between welding fume exposure and COPD in Korean shipyard welders. The study involved a group of male welders working at two shipyards who underwent an annual health examination in 2010. Subjects completed a questionnaire about smoking habits and occupational history and a pulmonary function test (PFT) was carried out with strict quality control measures. Welding fume exposure concentrations were estimated using 884 measurements taken between 2002 and 2009 in one of the shipyards. Multiple linear and logistic regression was employed to evaluate the association between cumulative fume exposure and lung function parameters, controlling for age, height and cigarette smoking. Two hundred and forty subjects participated, with a mean age of 48 and mean work duration of 15 years. The mean cumulative fume exposure was 7.7mg/m(3). The prevalence of COPD was 15%. FEV1 and FVC showed non-significant negative correlations with cumulative fume exposure. Odds ratios of COPD were significantly elevated for the middle (3.9; 95% CI 1.4-13.3) and high exposure groups (3.8; 95% CI 1.03-16.2) compared with the low fume exposure group. Our findings support an association between welding fume exposure and increased risk of COPD. Further prospective study is needed to investigate whether this is a causal relationship. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.