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Abstract Understanding the migration of trace contaminants during the production of U metal is vital for fabricating advanced nuclear fuels, for managing worker health and safety at foundry and processing facilities, and for advancing nuclear forensic science. A common method used to produce actinide metals is the bomb reduction of suitable U precursors. Here, we report the results of a series of experiments designed to quantitatively track the trace contaminants Th, Ca, and Mg through a bomb reduction of UF 4 using a vacuum induction furnace. In this series, UF 4 charges were doped with elemental Th at 0 (a blank), 1, 10, 100, and 1000 ppm Th/U. Following reduction, the metal ingot products and the associated slag and crucibles were individually digested and analyzed using inductively coupled plasma-mass spectrometry. The results show that Th fractionation occurred at all concentrations but was most significant, and near quantitative, in samples starting with Th concentrations below 100 ppm. Thorium was found to incorporate into the slag and crucible in roughly equal proportions during reduction. A significant amount of U and Ca migrated into the crucible walls, each correlating positively with the quantities of Mg migrating from the MgO crucible to the U metal product. [ABSTRACT FROM AUTHOR]

Objectives.The present study aimed at assessing bioelectric activity and cognitive functions in the workers on the conversion project of the “Shelter” object (SO) of the Chernobyl nuclear power plant into an environmentally safe system.Methods. A total of 196 men were included and examined before (t0) and after (t1) working on the SO in the period 2004–2008. They underwent a qEEG and a battery of neuropsychological and psychiatric assessments.Results. At t1, the organized type of qEEG shifted towards the disorganized one. An increase of spectral δ-power in the left frontotemporal area, of θ- and α-power in the left temporal area, with redistribution of α-activity to the front and reduction of dominant frequency in the left temporal area, were registered. Further, neurocognitive tests revealed the presence of mild cognitive disorders at t1. Interestingly, those subjects previously exposed to radiation with no consequences, were more resistant to these detrimental effects.Conclusions. Taken together, the disturbances observed may be considered as cognitive symptoms of a chronic fatigue syndrome resulting from the exposure to ionizing radiation. Simple and non-invasive assessments, such as those performed by us, may be helpful to detect early brain changes caused by the presence of radiological risk factors. [ABSTRACT FROM PUBLISHER]

The paper summarises the main findings on Chernobyl Nuclear Power Plant (CNPP) accident recovery workers from Latvia and their health disturbances, which have been studied by the authors during the last two decades. Approximately 6000 persons from Latvia participated in CNPP clean-up works in 1986-1991. During their work period in Chernobyl they were exposed to external as well as to internal irradiation, but since their return to Latvia they were living in a relatively uncontaminated area. Regular careful medical examinations and clinical studies of CNPP clean-up workers have been conducted during the 25 years after disaster, gathering knowledge on radiation late effects. The aim of the present review is to summarise the most important information about Latvian CNPP clean-up worker health revealed by thorough follow-up and research conducted in the period of 25 years after the accident. This paper reviews data of the Latvian State Register of Persons Exposed to Radiation due to CNPP Accident and gives insight in main health effects found by the researchers from the Centre of Occupational and Radiological Medicine (Pauls Stradiņš Clinical University Hospital) and Rīga Stradiņš University in a number of epidemiological, clinical, biochemical, immunological, and physiological studies. Latvian research data on health condition of CNPP clean-up workers in the late period after disaster indicate that ionising radiation might cause premature ageing and severe polymorbidity in humans. [ABSTRACT FROM AUTHOR]

This article discusses the availability and completeness of medical data on workers from the AREVA NC Pierrelatte nuclear plant and their possible use in epidemiological research on cardiovascular and metabolic disorders related to internal exposure to uranium. We created a computer database from files on 394 eligible workers included in an ongoing nested case-control study from a larger cohort of 2897 French nuclear workers. For each worker, we collected records of previous employment, job positions, job descriptions, medical visits, and blood test results from medical history. The dataset counts 9,471 medical examinations and 12,735 blood test results. For almost all of the parameters relevant for research on cardiovascular risk, data completeness and availability is over 90 %, but it varies with time and improves in the latest time period. In the absence of biobanks, collecting and computerising available good-quality occupational medicine archive data constitutes a valuable alternative for epidemiological and aetiological research in occupational health. Biobanks rarely contain biological samples over an entire worker's carrier and medical data from nuclear industry archives might make up for unavailable biomarkers that could provide information on cardiovascular and metabolic diseases [ABSTRACT FROM AUTHOR]

The aim of the study is to assess the health status of Kozloduy Nuclear Power Plant personnel in association with their occupational exposure to low doses of ionising radiation (IR) as well as with other factors of their working environment and to determine the probability of the occupational exposure to be a reason for the diagnosed malignant diseases (Probability of Causation - PC). More than 1000 occupationally exposed workers and non-exposed administrative staff have been studied during 1993-2008. No statistically significant variation in the average cumulative dose was found between the healthy people and the persons with at least one disorder. The highest rate of morbidity was registered in persons with doses up to 1 mSv. The analysis of parameters of peripheral blood showed that at occupational low-dose exposure the haemopoietic system completely preserves the tri-linear cell proliferation capacity of the bone marrow. The analysis of results of PC demonstrated that this is spontaneously arising malignant diseases, regardless of condition of work. [ABSTRACT FROM AUTHOR]

Background:A 15-country study of nuclear workers reported significantly increased radiation-related risks of all cancers excluding leukaemia, with Canadian data a major factor behind the pooled results. We analysed mortality (1956-1994) in the updated Canadian cohort and provided revised risk estimates.Methods:Employment records were searched to verify and revise exposure data and to restore missing socioeconomic status. Excess relative risks per sievert (ERR/Sv) of recorded radiation dose and 95% confidence intervals (CIs) were estimated using Poisson regression.Results:A significant heterogeneity of the dose-response for solid cancer was identified (P=0.02), with 3088 early (1956-1964) Atomic Energy of Canada Limited (AECL) workers having a significant increase (ERR/Sv=7.87, 95% CI: 1.88, 19.5), and no evidence of radiation risk for 42 228 workers employed by three nuclear power plant companies and post-1964 AECL (ERR/Sv=−1.20, 95% CI: <−1.47, 2.39). Radiation risks of leukaemia were negative in early AECL workers and non-significantly increased in other workers. In analyses with separate terms for tritium and gamma doses, there was no evidence of increased risk from tritium exposure. All workers had mortality lower than the general population.Conclusion:Significantly increased risks for early AECL workers are most likely due to incomplete transfer of AECL dose records to the National Dose Registry. Analyses of the remainder of the Canadian nuclear workers (93.2%) provided no evidence of increased risk, but the risk estimate was compatible with estimates that form the basis of radiation protection standards. Study findings suggest that the revised Canadian cohort, with the exclusion of early AECL workers, would likely have an important effect on the 15-country pooled risk estimate of radiation-related risks of all cancer excluding leukaemia by substantially reducing the size of the point estimate and its significance. [ABSTRACT FROM AUTHOR]

This article describes occupational health measures for workers involved in decontamination of radioactive material discharged around Fukushima Dai-ichi Nuclear Power Plant after the explosions in 2011. Decontamination is performed by removing radioactive particles (mainly cesium) from surfaces of soil, grass and trees, and buildings. Measurement of radiation doses is necessary to reduce exposure, and to determine whether workers can work below dose limits. Protective equipment for decontamination is determined based on the concentration of radiation in contaminated soil and the exposure to dust. Health examinations by physicians are mandated for decontamination workers upon hiring and every 6 months. While there is no possibility of acute radiation injury from decontamination, workers may be anxious about the unclear effects of chronic low level radiation exposure on health. Measures to protect the decontamination workers are the top priority. [ABSTRACT FROM PUBLISHER]

Safety in nuclear power plants (NPPs) in India is a very important topic and it is necessary to dissipate correct information to all the readers and the public at large. In this article, I have briefly described how the safety in our NPPs is maintained. Safety is accorded overriding priority in all the activities. NPPs in India are not only safe but are also well regulated, have proper radiological protection of workers and the public, regular surveillance, dosimetry, approved standard operating and maintenance procedures, a well-defined waste management methodology, proper well documented and periodically rehearsed emergency preparedness and disaster management plans. The NPPs have occupational health policies covering periodic medical examinations, dosimetry and bioassay and are backed-up by fully equipped Personnel Decontamination Centers manned by doctors qualified in Occupational and Industrial Health. All the operating plants are ISO 14001 and IS 18001 certified plants. The Nuclear Power Corporation of India Limited today has 17 operating plants and five plants under construction, and our scientists and engineers are fully geared to take up many more in order to meet the national requirements. [ABSTRACT FROM AUTHOR]

This research paper examines the health effects of people around the Chernobyl nuclear plant who suffered acute radiation sickness as a result of the nuclear reactor melt-down in 1968. The accident resulted in one-third of reported acute radiation sickness (ARS) cases mostly among the workers at the plant and the first responders to the accident. The general population was generally spared as was the evacuated population. During the first two months after the accident bone marrow failure was the main reason that exposed patients died. Skin doses exceeded bone marrow doses and 19 deaths were blamed on infection arising from the burns. In all 134 people were diagnosed and of these, 89 died. Long term treatment includes care of burns, skin atrophy and cataracts.

Purpose: To study chromosomal radiosensitivity in a population of radiation workers and investigate the possibility of an adaptive response in lymphocytes of workers after short-term occupational exposure to ionizing radiation. Materials and methods: The studied group comprised 41 workers temporarily employed at the Nuclear Power Plant Doel (Belgium) for reactor maintenance. A blood sample was taken before and directly after the exposure period of about 1 month. Chromosomal radiosensitivity was assessed in vitro by the G2 assay and the G0 micronucleus (MN) assay. For the MN assay, a low dose-rate (LDR) in vitro irradiation protocol was applied in addition to high dose-rate (HDR) irradiation of the blood samples in order to determine the dose-rate sparing (DRS) effect. Results: No statistically significant effect of the occupational exposures (up to 10 mSv) on the baseline MN frequencies without in vitro irradiation was observed. A comparison of the number of chromatid aberrations pre- and post-exposure shows no effect of the occupational exposure. On the other hand, the G0-MN assay with the LDR irradiation protocol reveals a systematic reduction in chromosomal radiosensitivity by the exposure, increasing with dose. For workers who received the highest dose (4-10 mSv) a statistically significant (p < 0.05) decrease of the in vitro induced MN yields and increase of the dose-rate sparing was observed. Conclusions: Short-term low-dose occupational exposure may act as an in vivo adaptive dose and stimulate repair in G0 lymphocytes. [ABSTRACT FROM AUTHOR]

Aim: Biomonitoring provides a useful tool to estimate the genetic risk from exposure to genotoxic agents. The aim of this study was to evaluate the frequencies of Micronuclei (MN) and other Nuclear abnormalities (NA) from exfoliated oral mucosal cells in Nuclear Power Station (NPS) workers. Materials and Methods: Micronucleus frequencies in oral exfoliated cells were done from individuals not known to be exposed to either environmental or occupational carcinogens (Group I). Similarly samples were obtained from full-time Nuclear Power Station (NPS) workers with absence of Leukemia and any malignancy (Group II) and workers diagnosed as leukemic patients and undergoing treatment (Group III). Results: There was statistically significant difference between Group I, Group II & Group III. MN and NA frequencies in Leukemic Patients were significantly higher than those in exposed workers &control groups (p < 0.05). Conclusion: MN and other NA reflect genetic changes, events associated with malignancies. Therefore, there is a need to educate those who work in NPS about the potential hazard of occupational exposure and the importance of using protective measures. [ABSTRACT FROM AUTHOR]

This paper presents a limited assessment of the conservatism of the Accident Sequence Evaluation Program (ASEP) human reliability analysis (HRA) procedure described in NUREG/CR-4772. The data for this studyare derived from simulator examination reports from the NRC requalification examination cycle for nuclear power plant operators. The ASEPprocedure was used to estimate human error probability (HEP) values for critical tasks, and the HEP results were compared with the failure rates observed in the examinations. The ASEP procedure was applied by PNNL operator license examiners who supplemented the limited information in the examination reports with expert judgment based upon their extensive simulator examination experience. Comparison of the average of the ASEP HEP values with the fraction of the population actually failed and demonstrated that the ASEP HEP values are larger (conservative) by a statistically significant average factor of two. Partitioning of tasks into subgroups based on the ASEP HEP values and comparison of the subgroup average ASEP HEP values with observed subgroup failure rates showed little or no conservatism for small ASEP HEP values, but considerable conservatism for larger ASEP HEP values. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses a study on psychological distress in workers, as well as posttraumatic stress response (PTSR) at the Fukushima Nuclear Power Plants in Japan.

Any potential health effects of radiation emitted from radionuclides deposited in the bodies of workers exposed to radioactive materials can be directly investigated through epidemiological studies. However, estimates of radionuclide exposure and consequent tissue-specific doses, particularly for early workers for whom monitoring was relatively crude but exposures tended to be highest, can be uncertain, limiting the accuracy of risk estimates. We review the use of job-exposure matrices (JEMs) in peer-reviewed epidemiological and exposure assessment studies of nuclear industry workers exposed to radioactive materials as a method for addressing gaps in exposure data, and discuss methodology and comparability between studies. We identified nine studies of nuclear worker cohorts in France, Russia, the USA and the UK that had incorporated JEMs in their exposure assessments. All these JEMs were study or cohort-specific, and although broadly comparable methodologies were used in their construction, this is insufficient to enable the transfer of any one JEM to another study. Moreover there was often inadequate detail on whether, or how, JEMs were validated. JEMs have become more detailed and more quantitative, and this trend may eventually enable better comparison across, and the pooling of, studies. We conclude that JEMs have been shown to be a valuable exposure assessment methodology for imputation of missing exposure data for nuclear worker cohorts with data not missing at random. The next step forward for direct comparison or pooled analysis of complete cohorts would be the use of transparent and transferable methods. [ABSTRACT FROM AUTHOR]

Germline minisatellite mutation rates were investigated in male workers occupationally exposed to radiation at the Sellafield nuclear facility. DNA samples from 160 families with 255 offspring were analysed for mutations at eight hypervariable minisatellite loci (B6.7, CEB1, CEB15, CEB25, CEB36, MS1, MS31, MS32) by Southern hybridisation. No significant difference was observed between the paternal mutation rate of 5.0% (37 mutations in 736 alleles) for control fathers with a mean preconceptional testicular dose of 9 mSv and that of 5.8% (66 in 1137 alleles) for exposed fathers with a mean preconceptional testicular dose of 194 mSv. Subgrouping the exposed fathers into two dose groups with means of 111 mSv and 274 mSv revealed paternal mutation rates of 6.0% (32 mutations in 536 alleles) and 5.7% (34 mutations in 601 alleles), respectively, neither of which was significantly different in comparisons with the rate for the control fathers. Maternal mutation rates of 1.6% (12 mutations in 742 alleles) for the partners of control fathers and 1.7% (19 mutations in 1133 alleles) for partners of exposed fathers were not significantly different. This study provides evidence that paternal preconceptional occupational radiation exposure does not increase the germline minisatellite mutation rate and therefore refutes suggestions that such exposure could result in a destabilisation of the germline that can be passed on to future generations. [ABSTRACT FROM AUTHOR]

The article discusses the task of Tokyo Electric Power (TEPCO) to clean up the Fukushima Daiichi with 6,000 technicians and engineers, truck drivers and builders at the frontline of the world's most hazardous industrial cleanup. The dangers faced by these men were underlined in October 2013 when 6 men were doused with contaminated water at a desalination facility. It cites the lack of full-time mental health counseling at the plan as Tepco workers worry about their health.

The article explores the challenging living and working conditions of the workers of nuclear energy firm Fukushima Daiichi in Japan. It mentions that the workers in the company are not offered by the management with health insurance as they are considered contract employees. According to the article, the workers also have problems accessing health clinics as the Japanese government denied follow-up checkups of people who have been exposed to a greater dose of radiation when the plant was damaged.

The author argues that the Japanese government and Tokyo Electric Power Co. (TEPCO) should prioritize the recognition and protection of the health and safety of front-line workers at the Fukushima nuclear power plant (NPP). She offers a background on the damages caused by the March 2011 Great East Japan earthquake and tsunami to the Fukushima NPP. She discusses how TEPCO has improved the work environment at the NPP following the death of one worker. She also offers ideas on the different heat-related illnesses that NPP workers might experience which include heat stroke, dehydration and heat stress.