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1.
J Environ Radioact ; 222: 106344, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32892902

RESUMO

The novel approach for optimising soil sampling strategies in areas affected by radionuclides is suggested. Major factors influencing the efficiency of soil sampling strategies, including (number of samples, sampling area size, sampling depth and spatial resolution of the sample sites are examined to provide optimisation of the soil sampling plan. The experimental field studies to validate the suggested approach were performed in 25 sampling units ranging from 1.2 × 1.2 m to 60 × 60 m size. The sampling units were selected on arable farmlands, natural meadow and former agricultural land), as well as coniferous and deciduous forests with contamination density of 137Cs ranging from 2.8 kBq·m-2 to 24.5 MBq·m-2. The studied areas were contaminated by both the global fallout and the Chernobyl radioactive particles of different types. To determine the values of standard deviation of the log of the soil contamination density of 137Cs, 25 to 256 soil samples were collected with an increment of 0.07-10 m within each sampling unit. It was found that the values of standard deviation of the log of the soil contamination density of 137Cs were not dependent on the mean contamination density, the type of radioactive deposition and the landscape features. The mean value of standard deviation calculated for all sites studied was estimated as 0.44 ± 0.15 and 0.30 ± 0.10 for the sampling area 0.001 m2 (∅37 mm) and 0.005 m2 (∅80 mm) at the relative measurement uncertainties lower than 10% (CI = 95%). Concentrations of 137Cs in the soil samples were statistically independent when sampling points were situated at a distance larger than 1 m one from each other. A simple method was developed for assessing minimum sample sizes required for estimation of the median or the geometric mean of radionuclide soil contamination with a relative uncertainty set by the user. The approach was also suggested for estimation of the uncertainty of soil contamination for the case of composite samples. The approach was implemented in the Ukrainian national requirements for assessment of quality of the soil.


Assuntos
Monitoramento Ambiental , Monitoramento de Radiação , Radioatividade , Poluentes Radioativos do Solo , Radioisótopos de Césio , Monitoramento Ambiental/métodos , Florestas , Monitoramento de Radiação/métodos , Solo
2.
Mar Pollut Bull ; 159: 111481, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32768672

RESUMO

The region around the Gulf is moving toward a nuclear energy option with the first nuclear power plant now operational in Bushehr, Iran. Others are soon to be commissioned in Abu Dhabi and in Saudi Arabia. For this reason, radiological safety is becoming a prime concern in the region. This review compiles published data on radionuclide concentrations in seawater, sediment, and biota that have been analyzed in the Gulf countries, along with spatial distribution patterns to enable a synoptic view of the available datasets. The seawater concentrations of 3H, 210Po, 210Pb, 137Cs, and 90Sr varied between 130 and 146, 0.48-0.68, 0.75-0.89, 1.25-1.38, 0.57-0.78 mBq L-1, respectively. The 226Ra concentration in seawater varied between 0.26 and 3.82 Bq L-1. Extremely high 40K concentrations between 132 and 149 Bq L-1 have been reported from the Iranian coast compared to 8.9-9.3 Bq L-1 from the western side of the Gulf. Concentrations of 40K, total 210Pb, 137Cs, 90Sr, 226Ra, 228Ra, 238U, 235U, 234U, 239+240Pu, and 238Pu were determined in sediment and ranged between 353 and 445, 23.6-44.3, 1.0-3.1, 4.8-5.29, 17.3-20.5, 15-16.4, 28.7-31.4, 1.26-1.30, 29.7-30.0, 0.045-0.21 and 0.028-0.03 Bq kg-1 dry weight, respectively. Significantly higher 137Cs values have been reported from the Iranian coast compared to the western coast of the Gulf. Whole fish concentrations of 40K, 226Ra, 224Ra, 228Ra, 137Cs, 210Po and 90Sr ranged between 230 and 447, 0.7-7.3, <0.5-6.6, <0.5-15.80, <0.17, 0.88-4.26 and 1.86-5.34 Bq kg-1 dry weight, respectively. 210Po was found to be highly concentrated in several marine organisms with the highest 210Po concentration found in the clam Marcia marmorata (193.5-215.6 Bq kg-1 dry weight). The review highlights the overall paucity of data and inconsistencies in the measurement of radionuclides throughout the Gulf region. Further, since the region is moving toward nuclear energy to meet its increasing energy demand, and coupled with the environmental effects from offshore oil exploration and the heavy impact of climate change, there is a pressing need to undertake a comprehensive marine radioactivity monitoring and assessment effort by conducting a joint cruise in the Gulf with participation of all the adjoining countries. Several recommendations on sampling marine matrixes in the Gulf are given with the aim of improving comparability of radionuclide data from the various studies undertaken in the Gulf region.


Assuntos
Monitoramento de Radiação , Radioatividade , Poluentes Radioativos da Água/análise , Animais , Irã (Geográfico) , Arábia Saudita , Água do Mar , Emirados Árabes Unidos
3.
J Environ Radioact ; 222: 106291, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32771855

RESUMO

This study deals with the geology in areas close to a large unexploited uranium deposit and the impact of bedrock characteristics on levels of radionuclides and other elements in soil and biota. Factors influencing soil inventory and ecosystem transfer are discussed, focussing on 238U, 226Ra, and 210Pb. Field work was carried out in Salangen Valley in Northern Norway. Sampling stations for soil and biota covered different habitats - grassland, birch forest and low alpine heathland. The geological survey confirmed uranium-bearing minerals in granitic gneiss and pegmatites. There was large variation in the local occurrence of uranium, reflecting the irregular nature of the pegmatite. Activity concentrations of 238U, 226Ra, and 210Pb in surface soil were elevated at sites close to U-enhanced bedrock, compared to sites with other types of bedrock. Particularly high soil levels were found for 226Ra and 210Pb, whereas activity concentrations of 238U were more variable, depending of local soil characteristics. Levels of other natural radionuclides (40K, 232Th) merely increased with soil mineral content, and concentrations of heavy metals were generally low at all sites. External dose rate (1 m above ground surface) was closely correlated with 226Ra levels in soil. Plant levels of 238U and 226Ra varied by several orders of magnitude depending on soil level and plant species, whereas plant levels of 210Pb and 210Po were largely affected by aerial fallout. Berries generally contained lower levels of 238U and 226Ra than green plant parts. As was the case for plants, the levels of 238U in earthworms were strongly correlated with the respective concentrations in the soil. Soil-to-plant transfer was markedly higher for 226Ra than for 238U. For both radionuclides, a positive correlation was found between concentration ratios of V. myrtillus (heath) and soil organic matter content. The 238U concentration ratios for earthworms were generally two orders of magnitude higher than for plants.


Assuntos
Florestas , Monitoramento de Radiação , Radioatividade , Poluentes Radioativos do Solo , Animais , Biota , Ecossistema , Geologia , Noruega , Solo
4.
J Environ Radioact ; 222: 106375, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32791372

RESUMO

The purpose of this work is to highlight the effects of ionizing radiation on the genetic material in higher plants by assessing both adaptive processes as well as the evolution of plant species. The effects that the ionizing radiation has on greenery following a nuclear accident, was examined by taking the Chernobyl Nuclear Power Plant disaster as a case study. The genetic and evolutionary effects that ionizing radiation had on plants after the Chernobyl accident were highlighted. The response of biota to Chernobyl irradiation was a complex interaction among radiation dose, dose rate, temporal and spatial variation, varying radiation sensitivities of the different plants' species, and indirect effects from other events. Ionizing radiation causes water radiolysis, generating highly reactive oxygen species (ROS). ROS induce the rapid activation of detoxifying enzymes. DeoxyriboNucleic Acid (DNA) is the object of an attack by both, the hydroxyl ions and the radiation itself, thus triggering a mechanism both direct and indirect. The effects on DNA are harmful to the organism and the long-term development of the species. Dose-dependent aberrations in chromosomes are often observed after irradiation. Although multiple DNA repair mechanisms exist, double-strand breaks (DSBs or DNA-DSBs) are often subject to errors. Plants DSBs repair mechanisms mainly involve homologous and non-homologous dependent systems, the latter especially causing a loss of genetic information. Repeated ionizing radiation (acute or chronic) ensures that plants adapt, demonstrating radioresistance. An adaptive response has been suggested for this phenomenon. As a result, ionizing radiation influences the genetic structure, especially during chronic irradiation, reducing genetic variability. This reduction may be associated with the fact that particular plant species are more subject to chronic stress, confirming the adaptive theory. Therefore, the genomic effects of ionizing radiation demonstrate their likely involvement in the evolution of plant species.


Assuntos
Adaptação Fisiológica , Acidente Nuclear de Chernobyl , Desastres , Fenômenos Fisiológicos Vegetais , Monitoramento de Radiação , Radioatividade , Plantas , Radiação Ionizante
5.
Sci Total Environ ; 737: 140291, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783865

RESUMO

This paper presents information on the concentration of radioactivity and chemicals at 12 water stations that used groundwater as their raw water supply source. The groundwater's radioactivity was higher than the treated, tap, and surface water, but lower than the national and international recommendations. At five stations (41.7%), the gross alpha contents were higher than the levels advised by Vietnam's regulations, but met the WHO and IAEA's recommendations. The mean activity (Bq L-1) gross alpha, gross beta, Ra-224, Ra-226, and Ra-228 were 0.093 ± 0.012, 0.221 ± 0.020, 0.031 ± 0.004, 0.028 ± 0.004, and 0.035 ± 0.001, respectively. The contribution of Ra-226 to the gross alpha was in a range of 23%-60% (r = 0.91, p value <0.001), and the ratio of Ra-226/Ra-228 ranged from 0.49-1.06. For the treated and tap water, each age groups' annual committed effective dose was lower than the international regulations. The concentration of the total dissolved solids, sulfate, chloride, sodium, barium, and manganese met the national regulations. However, during the rainy season, the surface water in the area was affected by saltwater intrusion, with salinity up to 4.1‰. Discriminant analysis was applied to study the differences among the water groups. As a result, the treated and tap water were separated from the others.


Assuntos
Monitoramento de Radiação , Radioatividade , Poluentes Radioativos da Água/análise , Saúde Pública , Vietnã , Abastecimento de Água
6.
J Environ Radioact ; 222: 106376, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32861138

RESUMO

In 2017, the Polish public consumed on average 0.61 kg of honey, while the European average consumption was 0.7 kg (Data on honey consumption in Poland, 2014) [http://www.portalspozywczy.pl]. The main point of this study was to investigate the 210Po activity concentrations in different types of floral and non-floral honey, type of clad honey is made of and honey yield in honey available on the Polish market. Activity of 210 Po in honey ranged from 0.006 ± 0.001 to 0.384 ± 0.004 Bq kg-1 with effective dose 0.005 ± 0.001 to 0.281 ± 0.003 µSv/year. The activity in honey was measured by alpha-spectrometry. The concentration of radionuclide depends on the raw material used by bees and plant type. The highest concentration of 210Po was observed in the honeydew honey and herbal honey.


Assuntos
Mel , Monitoramento de Radiação , Radioatividade , Animais , Polônia , Radioisótopos
7.
Chemosphere ; 257: 127267, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32534298

RESUMO

More than 9 years since the Fukushima Dai-ichi Nuclear Power Plant Accident (FDNPPA), the impact of FDNPPA on marine biota is being revealed. In this work, the evolution of FDNPPA derived 134Cs, 137Cs and 110mAg in dolphin fishes (Coryphaena hippurus) in the Northwest Pacific from Dec. 2011 to Sept. 2018 were studied. Bioconcentration factors (BCF) of radiocesium (29-69 with the average of 48) in dolphin fishes were calculated. The background level of 137Cs in dolphin fishes (<0.14 Bq/kgfresh weight) before FDNPPA was estimated. The radioactive levels of these three radionuclides in dolphin fishes decreased with time. Among them, 134Cs and 110mAg decreased at the half-lives of 158 days and 54 days at the population level, respectively. After May 2014, 134Cs and 110mAg cannot be detected and the activity of 137Cs returned to the background level before FDNPPA. Radiation dose assessment demonstrated that it was far from causing radiation harm to dolphin fishes in the open ocean of Northwest Pacific and humans who ingested them.


Assuntos
Peixes/metabolismo , Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos da Água/metabolismo , Animais , Radioisótopos de Césio , Humanos , Japão , Centrais Nucleares , Radioatividade , Poluentes Radioativos da Água/análise
8.
Environ Sci Pollut Res Int ; 27(26): 33032-33041, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32529611

RESUMO

Atmospheric radioactive airborne released from several natural and artificial sources can travel for long distances and disperse in different directions. Both the physical and chemical characteristics of the atmospheric aerosols control this movement. The concentrations of 210Pb, 210Po, 7Be, 40K and 137Cs radionuclides in the ground surface air were determined in three particle sizes (2.4-10.2, 0.73-2.4 and less than 0.73 µm). High-volume air samples were collected from five different locations representing the five governorates of Kuwait using high-volume air samplers connected to a five-stage cascade impactor. The radioactivity concentrations of almost all fallout radionuclides were concentrated on the fine particle size fractions. The cosmogenic 7Be radioactivity level in all locations was relatively comparable and varied between 1.16 and 18.38 mBq/m3, with a geometric mean value of 6.80 mBq/m3. 137Cs was infrequently recorded with concentration varied between 4 and 14.3 µBq/m3. The geometric mean levels of the 210Po and 210Pb were 0.899 mBq/m3 and 1.03 mBq/m3, respectively, indicating that anthropogenic sources likely enrich 210Po. 40K was concentrated on large particle size fractions with a geometric mean value of 2.34 mBq/m3, reflecting the effects of the local dust sources. It was concluded that the radiological hazards due to airborne radioactive inhalation are low and can be negligible, where the annual estimated effective dose is about 64.0 µSv. The radioactive airborne measurements compose the base of estimating the aerosols residence time, resuspension rate of dust, soil redistribution and source apportionment, particularly the 210Pb and 210Po radionuclides.


Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação , Radioatividade , Aerossóis , Poeira/análise , Kuweit
9.
PLoS One ; 15(4): e0232259, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353020

RESUMO

This article proposes and examines gender and life-stage factors as determinants of public worry and risk avoidance in a nuclear fallout scenario. Drawing on a survey (N 2,291) conducted in Sweden, the article demonstrates statistically significant results that women as well as parents with children at home are more likely to express high levels of worry for radiation exposure and have a preference to move away from a fallout area despite assurance of successful remediation. Moreover, a negative relationship is shown between age and both worry for radiation exposure and preference to move. These novel results from Northern Europe thus support a life-stage framing of public risk attitudes. As radiation physicists develop new methods showing that women and children are at higher risk of cancer than other groups at the same radiation exposure, we may actually see the precaution among women and parents as a regulating mechanism for the higher objective risk they face. The results are moreover in agreement with studies of public risk reactions in Japan, creating a strong knowledge base that human-induced radiation pollution is largely an intolerable risk to the public. Considering the public opinion, managing an intolerable risk through risk mitigation by remediation alone is likely insufficient in many cases. A viable strategy would offer a range of social support options that enable individual decision-making and the protection of risk groups.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluição Ambiental/estatística & dados numéricos , Cinza Radioativa/estatística & dados numéricos , Adulto , Europa (Continente) , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Radioatividade , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Inquéritos e Questionários , Suécia
10.
J Environ Radioact ; 219: 106283, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32452424

RESUMO

Ambient radioactivity and atmospheric electricity are inextricably linked phenomena. In order to assess the role of ambient radioactivity in the local variability of the atmospheric electric field at an urban site, simultaneous measurements of radon concentration, gamma radiation, and atmospheric electric field are carried out in the city of Porto, Portugal. Both radon and gamma radiation display an average daily cycle peaking before sunrise, but with considerable variability from day to day, particularly in amplitude. The atmospheric electric field displays a daily cycle with a minimum at dawn and maximum in the early afternoon, as well as a secondary peak in the early morning. The temporal variation of the daily patterns is analysed by means of an empirical orthogonal function analysis, and related to local meteorological parameters. The variability of the local atmospheric electric field is mainly determined by aerosol transport and accumulation close to the surface associated with local meteorological conditions and atmospheric stability rather than by conductivity variations associated with ambient radioactivity.


Assuntos
Eletricidade , Poluentes Radioativos do Ar , Atmosfera , Cidades , Portugal , Monitoramento de Radiação , Radioatividade , Radônio
11.
Sci Total Environ ; 733: 139340, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464573

RESUMO

BACKGROUND: Exposure to ionizing radiation increases the risk of chronic metabolic disorders such as insulin resistance and type 2 diabetes. Internal ionizing radiation from inhaled radioactive aerosol may contribute to the associations between fine particulate matter (PM2.5) and gestational diabetes mellitus (GDM). METHODS: We used the Massachusetts Registry of Vital Records to study 1,061,937 pregnant women from 2001 to 2015 with a singleton pregnancy without pre-existing diabetes. Gross ß activity measured by seven monitors of the U.S. Environmental Protection Agency's RadNet monitoring network was utilized to represent ambient particle radioactivity (PR). We obtained GDM status from birth certificates and used logistic regression analyses adjusted for socio-demographics, maternal comorbidities, PM2.5, temperature and relative humidity. We also examined effect modification by smoking habits. RESULTS: Ambient particle radioactivity exposure during first and second trimester of pregnancy was associated with higher odds of GDM (OR: 1.18 (95% CI 1.10 to 1.22). Controlling for PM2.5 did not substantially change the effects of PR on GDM. In women that reported being former or current smokers, the association between PR and GDM was null. In the full cohort, the overall effect of PM2.5 on GDM without adjusting for PR was not significant. CONCLUSION: This is the first population-based study to examine the association between particle radioactivity and gestational diabetes mellitus - one of the most common pregnancy-related diseases with lifelong effects for the mother and the fetus. This finding has important public health policy implications because it enhances our understanding about the toxicity of PR, a modifiable risk factor, which to date, has been considered only as an indoor and occupational air quality risk.


Assuntos
Poluentes Atmosféricos/análise , Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Radioatividade , Estudos de Coortes , Feminino , Humanos , Massachusetts , Material Particulado/análise , Gravidez , Estados Unidos
12.
J Environ Radioact ; 218: 106260, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32421580

RESUMO

This paper reports concentrations of γ-emitter radionuclides (40K, 137Cs, 210Pb, 226Ra, 228Ra, 228Th and 234Th) and some metals (Al, Cr, Fe, Co, Ni, Cu, Zn, As, Sr, Cd, Sb, Cs, Pb, Th and U) in surficial sediments from the Ankobra, Pra and Volta estuaries, in Ghana. Artisanal gold-mining in the Ankobra and Pra basins promoted moderate enrichments of As, Sb, Cu, Cs and Cr in their estuarine sediments, with respect to the reference background of the Volta Estuary. Radionuclide concentrations were in the range found in the Earth's crust. Present data do not support any conclusion on their potential enrichments due to gold-mining activities. Radionuclide isotopic ratios revealed a transfer of 228Ra from sediments to the water column. Pearson correlation coefficient matrices showed different patterns, which were reasonably understood after novel approaches: i) inter-estuaries comparison of slopes in the linear regressions of element-concentrations vs Al, Fe and Cs; ii) study of Al-normalized concentrations of elements; iii) excess 210Pb informing on local sedimentary conditions. The metal enrichments observed in the Ankobra and Pra estuaries are associated with the Fe-rich compounds in sulphide ores (such as FeAsS) transported along the river course and deposited in the estuary.


Assuntos
Metais Pesados , Monitoramento de Radiação , Radioatividade , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Gana , Ouro , Mineração , Rios
13.
J Environ Radioact ; 218: 106262, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32421582

RESUMO

The measurement of radioactivity in food and agricultural ecosystems is an essential task for keeping the population safe after a nuclear emergency. Prior to the Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in 2011, the probability of such an accident, combining complex effects of natural and technical factors, was not reflected in detail in national emergency preparedness guidelines. The lack of such guidelines resulted in a limited efficiency response to the Fukushima accident in agriculture. This outcome showed a need for the preparation of such guidelines as a part of emergency preparedness for nuclear and radiological emergences. This paper provides information and generic, non-country-specific guidance on approaches to sampling food. The paper is intended for scientists, policy makers and decision makers involved in nuclear emergency preparedness and responses, particularly on large scales and at different stages of nuclear emergency based on lessons learned from the FDNPP accident.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Radioatividade , Agricultura , Radioisótopos de Césio , Ecossistema , Emergências , Humanos , Japão , Centrais Nucleares , Solo , Tóquio
14.
Environ Sci Pollut Res Int ; 27(20): 25475-25493, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32350837

RESUMO

Nasser Lake provides more than 95% of the Egyptian freshwater budget. The levels, spatial distributions, and risk assessments of heavy metals and natural radioactivity were investigated in the water and sediments in the main channel and khors (side extensions) of Nasser Lake in January 2017. Several indices were used to determine the quality and pollution degree of the water and sediments. The water indices included the heavy metal pollution index and metal contamination index, while the sediment indices were based on the (a) the metal levels as the enrichment factor and geo-accumulation index, and (b) the radioactivity as radium equivalent activity, absorbed dose rate, and external hazard indices. All index values were lower than their global mean values. Also, the results of the noncarcinogenic human health risk via water ingestion were below the threshold risk level. The obtained results indicate the safely used of Nasser Lake water for different purposes.


Assuntos
Metais Pesados/análise , Radioatividade , Poluentes Químicos da Água/análise , China , Egito , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Lagos , Medição de Risco
15.
J Environ Radioact ; 220-221: 106265, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32392130

RESUMO

Most available measurement methods and protocols for radioactive materials are focused on the use of high-precision sampling and analysis and do not consider the practicality of these techniques in the case of large-scale emergencies involving high numbers of samples and measurements. The experience gained after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident has demonstrated a need for optimization of sampling and measurement programmes in the case of nuclear emergency that affects food and agriculture. Under these conditions, resources for implementation of monitoring and allocations for sampling and measurements might be limited, and urgent information is needed for effective emergency response. This paper supplies a historical overview of sampling and analytical techniques for assessment of radionuclides in the agricultural environments and foodstuffs and is intended for use in research, policy and decision-making in nuclear emergency preparedness and response, particularly with respect to large scale accidents.


Assuntos
Monitoramento de Radiação , Radioatividade , Agricultura , Emergências , Acidente Nuclear de Fukushima , Japão , Centrais Nucleares , Solo
16.
Environ Sci Pollut Res Int ; 27(24): 29812-29823, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32232758

RESUMO

Our world is subject to various kinds of pollution and contamination due to rapid growth and development of industrialization. Though, industries are helping to improve the human life style in many ways in day to day life such as power generation to treatment of diseases. At the same time, industries emit the waste which causes major environmental pollution and leads to harmful for all living organism. As the renewable energy sources are depleting, energy/power generation become a major research around the world. Nuclear energy is one of the promising energy to sort out the energy demand, but the problem associated with the nuclear energy is the management and treatment of radioactive waste/emission/effluent since which is more dangerous to all living organism. There is a large scale contamination of radioactive waste associated for the past 60 years of global nuclear activity. It is necessary to pay special attention to the management of radioactive wastes in order to approach pollution-free environment and avoid diseases to living organism through various clean-up strategies. In this review, we discussed the wide ranges of strategies available for radioactive waste management such as physical, chemical, and biological methods. Bioremediation may be the powerful tool for treatment of radioactive wastes. Additionally, discussed on recent advancement have been made in treatment of radioactive waste through microbial transformation as well as phytoremediation which play a major role in disposal of radioactive waste.


Assuntos
Energia Nuclear , Resíduos Radioativos , Radioatividade , Gerenciamento de Resíduos , Biodegradação Ambiental , Humanos
17.
Chemosphere ; 250: 126315, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32234624

RESUMO

Uranium (U) is both chemically toxic and radioactive. Uranium mill tailings (UMTs) are one of the most important sources of U contamination in the environment, wherein the mechanisms that control U release from UMTs with different granularities have not yet been well understood. Herein, the release behaviours and underlying release mechanisms of U from UMTs with five different particle size fractions (<0.45, 0.45-0.9, 0.9-2, 2-6 and 6-10 mm) were studied with a well-defined leaching test (ANS 16.1) combined with geochemical and mineralogical characterizations. The results showed that the most remarkable U release unexpectedly emerged from UMT2-6 mm; in contrast, the smallest particle size UMT<0.45 mm contributed to the least U release. The predominant mechanism of U release from UMT2-6 mm was the oxidative dissolution of U-bearing sulfides, while abundant gypsum present in UMT<0.45 mm inhibited U release. The study highlights the importance of combined geochemical and mineralogical investigation when performing leaching tests of mineral-containing hazardous materials such as UMTs with consideration of particle size effects. The findings also indicate that elevating the content of gypsum and avoiding the oxidation of sulfides can effectively help immobilize and minimize the residual U release from the UMTs.


Assuntos
Urânio/química , Poluentes Radioativos da Água/química , Sulfato de Cálcio , Minerais , Tamanho da Partícula , Radioatividade , Poluentes Radioativos do Solo/análise , Poluentes Radioativos do Solo/química , Urânio/análise , Poluentes Radioativos da Água/análise
18.
J Environ Radioact ; 217: 106220, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32217252

RESUMO

Abnormal particulate radionuclides (65Zn, 134Cs and 137Cs) were detected at the CTBTO RN58 station which is located near North Korea between 12 and March 14, 2016. Detection ratio for caesium (134Cs/137Cs) shows that the product origin was nuclear explosion and dilution factors at RN58, released from DPRK test site, show clear correlation with radioactivity concentration of two samples. The detected radionuclides may be originated from the third nuclear test, February 2013. Half-life, radionuclides fractionation, MDC, and device design are attributed to no detection of other nuclides. Most of radionuclides have been decayed away and relatively long half-life nuclides might be in the third test site but they were displaced deep inside the area by fractionation during the explosion. Considering 65Zn activity ratio to 137Cs which is higher than historical ratios at Brunswick in 1968, there is a possibility that the third DPRK nuclear test was a "salted" nuclear bomb test using zinc as jacket instead of fissionable 238U around the secondary stage fusion fuel.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Radioatividade , Poluentes Radioativos do Ar , Radioisótopos de Césio , República Democrática Popular da Coreia , Zinco , Radioisótopos de Zinco
19.
Mar Pollut Bull ; 154: 111041, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32174494

RESUMO

Heavy metal assessment and natural radioactivity determination in sediments of North Cyprus (Mediterranean coast) were carried out using different analysis methods. The average activity concentrations (range) of 226Ra, 232Th, and 40K were found to be 20.1 (30.6-9.2) Bq kg-1dry weight, 18.4 (26.9-12.4) Bq kg-1dw, and 467.3 (619.9-147.6) Bq kg-1dw, respectively. The average activity concentrations of 226Ra and 232Th in the sediment samples were less than the acceptable limits, whereas the average activity concentration of 40K in the sediment samples was higher than the worldwide average concentration. With regard to the studied heavy metals, the corresponding decreasing average concentration orders were found to be Mn > Zn > Cr > Ni > Cu > Pb. The heavy metal concentration values that were determined for sediment samples were compared with the values obtained in other studies. According to contamination indexes, the results (except for Cu in S-9) indicated no significant contaminated area.


Assuntos
Metais Pesados , Monitoramento de Radiação , Radioatividade , Poluentes Radioativos da Água/análise , Chipre , Monitoramento Ambiental , Sedimentos Geológicos , Mar Mediterrâneo , Poluentes Químicos da Água
20.
Isotopes Environ Health Stud ; 56(3): 324-333, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32192356

RESUMO

Evaluated has been radioactive contamination with 137Cs in parallel to occurrence of 40K and total K in 31 species of medicinal mushrooms from Yunnan, China. We chose species that were not previously studied. The activity concentrations of 137Cs in the medicinal fungi in this study were low. The maximum values were 54 ± 4 Bq kg-1 dry biomass (db) in caps and 48 ± 5 Bq kg-1 db in stipes of saprotrophic fungus Gerronema xanthophyllum from the family of Tricholomataceae. Mushrooms with relatively higher activity concentrations of 40K were among the non-polypore species but certain species from the genus Ganoderma such as G. applanatum, G. capense, G. philippii and G. sinense showed 40K in the higher range of 900 ± 240 to 1400 ± 340 Bq kg-1 db. The concentrations of total K in the fungal materials in this study were in the range from 2.9 ± 6.5 g kg-1 db in Fomes rufolaccatus to 110 ± 6 g kg-1 db in G. xanthophyllum. The species studied, which represented both some popular wood-decaying polypore fungi but also terrestrial forms from the herbal medicine of China, can be considered as little contaminated with 137Cs and potentially good source of leachable K in extract and decoction or as a powdered form in capsules.


Assuntos
Agaricales/química , Radioisótopos de Césio/análise , Carpóforos/química , Radioisótopos de Potássio/análise , Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise , China , Medicina Tradicional Chinesa , Radioatividade
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