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A Simulation to Assess the Probability of the Spread of Radioactive Materials from the Zaporizhzhia Nuclear Power Plant using the HYSPLIT Model
2024
Valizadeh, Behshad | Heydarizade, Yassin | Tayebi, Javad | Rezaie, Mohammad Reza
Today, world pollution is increasing, and many pollutants such as radioactive elements enter to environment through human activity contaminants play an essential role in human life and health. Therefore, the examination of models for dispersion caused by radioactive substances is an important issue. This article is a simulation study of the hypothetical scenario of the Zaporizhzhia Nuclear Power Plant (ZNPP) in Ukraine, which is one of the NPPs in Europe. This scenario includes the occurrence of an accident in the power plant that entry of pollutants to environment and creates an environmental disaster. The simulation of this scenario was done using the Hyspli4 )Hybrid Single-Particle Lagrangian Integrated Trajectory) model and NOAA website data of ZNPP (include the wind information, temperature, humidity, and atmospheric pressure in different spatial and temporal scales) to predict and deal with pollutants. The simulation was conducted in the first week of April 2023 for 131 I and 137Cs elements, which are important elements that come out of the power plant and cause many problems. The results show the highest annual dose and concentration are 4.6 mSv/year and 2.7E+06 Bq.s/m3 respectively. It also shows that in the event of pollution, the entry of contaminated materials into the Dnieper River and the western edge of the blackened sea will bring a great disaster. Also, the eastern and northeastern regions of Ukraine, especially Kharkiv and the western borders of Russia, lead to pollution that causes radiation hazard, so the news should be shared with everyone before an actual incident occurs.
اظهر المزيد [+] اقل [-]Fluctuating asymmetry of invertebrate populations as a biological indicator of environmental quality.
1993
Clarke G.M.
Can stable elements (Cs and Sr) be used as proxies for the estimation of radionuclide soil-plant transfer factors?
2022
Guillén, J. | Beresford, N.A. | Baigazinov, Zh | Salas, A. | Kunduzbaeva, A.
Transfer parameters are key inputs for modeling radionuclide transfer in the environment and estimating risk to humans and wildlife. However, there are no data for many radionuclide-foodstuff/wildlife species combinations. The use of parameters derived from stable element data when data for radionuclides are lacking is increasingly common. But, do radionuclides and stable elements behave in a sufficiently similar way in the environment? To answer this question, at least for soil to plant transfer, sampling was conducted in four different countries (England, Kazakhstan, Spain and Ukraine) affected by different anthropogenic radionuclide source terms (in chronological order: global fallout, Semipalatinsk Test Site, the 1957 Windscale accident and the 1986 Chernobyl accident) together with a bibliographical review. Soil to grass transfer parameters (ratio between dry matter concentrations in plant and soil), Fᵥ, for ¹³⁷Cs and ⁹⁰Sr were significantly higher than those for stable elements, suggesting that the use of the latter could lead to underestimating radionuclide concentrations in plant samples Transfer parameters for ¹³⁷Cs and stable Cs were linearly correlated, with a slope of 1.54. No such correlation was observed for ⁹⁰Sr and stable Sr, the mean value of the ⁹⁰Sr:Sr ratio was 35 ranging (0.33–126); few data were available for the Sr comparison. The use of radionuclide transfer parameters, whenever possible, is recommended over derivation from stable element concentrations. However, we acknowledge that for many radionuclides there will be few or no radionuclide data from environmental studies. From analyses of the data collated there is evidence of a decreasing trend in the Fᵥ(¹³⁷Cs)/Fᵥ(Cs) ratio with time from the Chernobyl accident.
اظهر المزيد [+] اقل [-]Using reservoir sediment deposits to determine the longer-term fate of chernobyl-derived 137Cs fallout in the fluvial system
2021
Ivanov, M.M. | Konoplev, A.V. | Walling, D.E. | Konstantinov, E.A. | Gurinov, A.L. | Ivanova, N.N. | Kuzmenkova, N.V. | Tsyplenkov, A.S. | Ivanov, M.A. | Golosov, V.N.
Vast areas of Europe were contaminated by the fallout of ¹³⁷Cs and other radionuclides, as a result of the Chernobyl accident in 1986. The post-fallout redistribution of Chernobyl-derived ¹³⁷Cs was associated with erosion and sediment transport processes within the fluvial system. Bottom sediments from lakes and reservoirs can provide a valuable source of information regarding the post-fallout redistribution and fate of ¹³⁷Cs released by the Chernobyl accident. A detailed investigation of sediment-associated ¹³⁷Cs in the bottom sediments of a reservoir in a Chernobyl-affected area in Central Russia has been undertaken. A new approach, based on the vertical distribution of ¹³⁷Cs activity concentrations in the reservoir bottom sediment makes it possible to separate the initially deposited bottom sediment, where the ¹³⁷Cs activity reflects the direct fallout of Chernobyl-derived ¹³⁷Cs to the reservoir surface and its subsequent incorporation into sediment deposited immediately after the accident, from the sediment mobilized from the catchment deposited subsequently. The deposits representing direct fallout from the atmosphere was termed the “Chernobyl peak”. Its shape can be described by a diffusion equation and it can be distinguished from the remaining catchment-derived ¹³⁷Cs associated with sediment accumulated with sediments during the post-Chernobyl period. The ¹³⁷Cs depth distribution above the "Chernobyl peak" was used to provide a record of changes in the concentration of sediment-associated ¹³⁷Cs transported from the upstream catchment during the post-Chernobyl period. It was found that the ¹³⁷Cs activity concentration in the sediment deposited in the reservoir progressively decreased during the 30-year period after the accident due to a reduction in the contribution of sediment eroded from the arable land in the catchment. This reflects a reduction in both the area of cultivated land area and the reduced incidence of surface runoff from the slopes during spring snowmelt due to climate warming.
اظهر المزيد [+] اقل [-]Potential phytomanagement of military polluted sites and biomass production using biofuel crop miscanthus x giganteus
2019
Pidlisnyuk, Valentina | Erickson, Larry | Stefanovska, Tatyana | Popelka, Jan | Hettiarachchi, Ganga | Davis, Lawrence | Trögl, Josef
This study aims to summarize results on potential phytomanagement of two metal(loid)-polluted military soils using Miscanthus x giganteus. Such an option was tested during 2-year pot experiments with soils taken from former military sites in Sliač, Slovakia and Kamenetz-Podilsky, Ukraine. The following elements were considered: As, Cu, Fe, Mn, Pb, Sr, Ti, Zn and Zr. M. x giganteus showed good growth at both military soils with slightly higher maximum shoot lengths in the second year of vegetation. Based on Principal Component Analysis similarities of metal(loid) uptake by roots, stems and leaves were summarized. Major part of the elements remained in M. x giganteus roots and rather limited amounts moved to the aerial parts. Levels taken up decreased in the second vegetation year. Dynamics of foliar metal(loid) concentrations divided the elements in two groups: essential elements required for metabolism (Fe, Mn, Cu, and Zn) and non-essential elements without any known metabolic need (As, Sr, Ti, and Zr). Fe, Mn, Ti and Sr showed similar S-shaped uptake curve in terms of foliar concentrations (likely due to dilution in growing biomass), while Cu exhibited a clear peak mid-season. Behavior of Zn was in between. Foliar Zr and As concentrations were below detection limit. The results illustrated a good potential of M. x giganteus for safely growing on metal-polluted soils taken from both military localities.
اظهر المزيد [+] اقل [-]Genetic, epigenetic and microbiome characterisation of an earthworm species (Octolasion lacteum) along a radiation exposure gradient at Chernobyl
2019
Newbold, Lindsay K. | Robinson, Alex | Rasnaca, I. | Lahive, Elma | Soon, Gweon H. | Lapied, Emmanuel | Oughton, Deborah | Gashchak, Sergey | Beresford, Nicholas A. | Spurgeon, David J.
The effects of exposure to different levels of ionising radiation were assessed on the genetic, epigenetic and microbiome characteristics of the “hologenome” of earthworms collected at sites within the Chernobyl exclusion zone (CEZ). The earthworms Aporrectodea caliginosa (Savigny, 1826) and Octolasion lacteum (Örley, 1881) were the two species that were most frequently found at visited sites, however, only O. lacteum was present at sufficient number across different exposure levels to enable comparative hologenome analysis. The identification of morphotype O. lacteum as a probable single clade was established using a combination of mitochondrial (cytochrome oxidase I) and nuclear genome (Amplified Fragment Length Polymorphism (AFLP) using MspI loci). No clear site associated differences in population genetic structure was found between populations using the AFLP marker loci. Further, no relationship between ionising radiation exposure levels and the percentage of methylated loci or pattern of distribution of DNA methylation marks was found. Microbiome structure was clearly site dependent, with gut microbiome community structure and diversity being systematically associated with calculated site-specific earthworm dose rates. There was, however, also co-correlation between earthworm dose rates and other soil properties, notably soil pH; a property known to affect soil bacterial community structure. Such co-correlation means that it is not possible to attribute microbiome changes unequivocally to radionuclide exposure. A better understanding of the relationship between radionuclide exposure soil properties and their interactions on bacterial microbiome community response is, therefore, needed to establish whether these the observed microbiome changes are attributed directly to radiation exposure, other soil properties or to an interaction between multiple variables at sites within the CEZ.
اظهر المزيد [+] اقل [-]Impact of wildfire on 137Cs and 90Sr wash-off in heavily contaminated forests in the Chernobyl exclusion zone
2020
Igarashi, Yasunori | Onda, Yūichi | Wakiyama, Yoshifumi | Konoplev, Alexei | Zheleznyak, Mark | Lisovyi, Hlib | Laptev, Gennady | Damiyanovich, Volodyill | Samoilov, Dmitry | Nanba, Kenji | Kirieiev, Serhii
Wildfires may play a role in redistributing radionuclides in the environment in combination with hydrological processes such as surface runoff and soil erosion. We investigated plot-scale radionuclide wash-off at forest sites affected by wildfires in the Chernobyl Exclusion Zone (CEZ). We also compared speciation of the washed-off radionuclides with those in previous studies conducted just after the accident in 1986. We observed the surface runoff and the radionuclide wash-off with a soil erosion plot at forest and post-fire sites during May–September 2018. In the post-fire site, 2.81 mm of surface runoff was observed in at least three flow events resulting from 285.8 mm total rainfall. The fluxes of dissolved and particulate ¹³⁷Cs were estimated as 4.9 and 161 Bq m⁻², respectively. The dissolved phase ⁹⁰Sr flux was estimated as 214 Bq m⁻². At the forest site, a single surface runoff (0.67 mm) event was generated by rainfall of 182.2 mm. The fluxes of dissolved and particulate ¹³⁷Cs wash-off values were 6.2 and 8.6 Bq m⁻², respectively. The flux of dissolved ⁹⁰Sr wash-off from the forest was estimated as 45.1 Bq m⁻². The distribution coefficient, which indicates the dissolved-particulate form of radionuclides, in the post-fire site was 30 times higher than that in the forest site, indicating the importance of particulate ¹³⁷Cs wash-off after fire in the CEZ. The entrainment coefficients for dissolved and particulate ¹³⁷Cs concentrations were around 50 times lower than those obtained in the corresponding position within the CEZ immediately after the accident in 1987. The effect of downward migration of ¹³⁷Cs over 30 years led to decreased entrainment coefficients for dissolved and particulate ¹³⁷Cs. The effect of downward migration of radionuclides was considered sufficient to indicate changes in normalized liquid and solid radionuclides wash-off entrainment coefficient and the distribution coefficient in this study.
اظهر المزيد [+] اقل [-]Use of natural and artificial radionuclides to determine the sedimentation rates in two North Caucasus lakes
2020
Kuzmenkova, Natalia V. | Ivanov, Maxim M. | Alexandrin, Mikhail Y. | Grachev, Alexei M. | Rozhkova, Alexandra K. | Zhizhin, Kirill D. | Grabenko, Evgeniy A. | Golosov, Valentin N.
The specific activities of natural (²¹⁰Pb, ²²⁶Ra, and ²³²Th) and artificial (¹³⁷Cs, ²³⁹,²⁴⁰Pu, and ²⁴¹Am) radionuclides in the sediments of two North Caucasus lakes were determined. The two lakes, Lake Khuko and Lake Donguz-Orun, differ in their sedimentation conditions. Based on the use of unsupported ²¹⁰Pbₑₓ and both Chernobyl-derived and bomb-derived ¹³⁷Cs as chronological markers, it was established that the sedimentation rates in Lake Khuko over the past 55–60 y did not exceed 0.017 cm y⁻¹. Sedimentation rates in Lake Donguz-Orun were found to be more than an order of magnitude higher. In the latter case, the sedimentation rates for the period from 1986 to the present were over 1.5 times higher than they were for the period 1963–1986. The differences in sedimentation rates were due to differences in the rates of denudation of their respective catchment areas. The specific activities of artificial radionuclides (¹³⁷Cs, 2600 Bq kg⁻¹; ²³⁹,²⁴⁰Pu, 162 Bq kg⁻¹; and ²⁴¹Am, 36 Bq kg⁻¹) and their ratios in the sediments of Lake Khuko show that their deposition was mainly due to global stratospheric fallout of technogenic radionuclides associated with nuclear bomb testing during 1954–1963—rather than fallout from the Chernobyl accident. Several factors, including the mode of precipitation, features of the surface runoff, and location of Lake Khuko, were responsible for the accumulation of artificial radionuclides.
اظهر المزيد [+] اقل [-]HCH and lindane contaminated sites: European and global need for a permanent solution for a long-time neglected issue
2019
Vijgen, John | de Borst, Bram | Weber, Roland | Stobiecki, Tomasz | Forter, Martin
During the last 70 years 1, 2, 3, 4, 5, 6-Hexachlorocyclohexane (HCH) has been one of the most extensively used pesticides. Only the gamma-isomer has insecticidal properties. For the marketing of gamma-HCH (lindane) the other 85% HCH isomers which are formed as by-products during HCH production had to be separated and became finally hazardous waste. For each tonne of lindane 8–12 tonnes of waste HCH isomers were produced and production of the approximately 600,000 t of lindane has therefore generated 4.8 to 7.2 million tonnes of HCH/POPs waste. These waste isomers were mostly buried in uncontrolled dumps at many sites around the world. The stockpiles and the large contaminated sites can be categorized as “mega-sites”. Countries with HCH legacy problems include Albania, Argentina, Austria, Azerbaijan, Brazil, China, Croatia, Czech Republic, France, Germany, Hungary, India, Italy, Japan, Macedonia, Nigeria, Poland, Romania, Russia, Slovakia, South Africa, Spain, Switzerland, Turkey, The Netherlands, UK, Ukraine and the USA.As lindane and alpha- and beta-HCH have been listed as POPs in the Stockholm Convention since August 2010, the problem of stockpiles of HCH waste is now documented and globally acknowledged.This article describes briefly the legacy of HCH and lindane that has been created. Three of the mega-sites are being discussed and demonstrate the increase in pollution footprint over time. Recent developments in the EU (including the Sabinanigo project in Aragon/Spain) and on a global level are presented. A short overview is given on lack of activities and on actions of countries within their obligations as Parties of the Stockholm Convention. Furthermore, current country activities supported by the Global Environment Facility (GEF), the “financing mechanism” of the convention, are listed. Finally, conclusions and recommendations are formulated that will contribute to the solution of this problem over the next 25 years.
اظهر المزيد [+] اقل [-]Abundance of birds in Fukushima as judged from Chernobyl
2012
Møller, A. P. (Anders Pape) | Hagiwara, A. (Atsushi) | Matsui, Shin | Kasahara, Satoe | Kawatsu, Kencho | Nishiumi, Isao | Suzuki, Hiroyuki | Ueda, Keisuke | Mousseau, Timothy A.
The effects of radiation on abundance of common birds in Fukushima can be assessed from the effects of radiation in Chernobyl. Abundance of birds was negatively related to radiation, with a significant difference between Fukushima and Chernobyl. Analysis of 14 species common to the two areas revealed a negative effect of radiation on abundance, differing between areas and species. The relationship between abundance and radiation was more strongly negative in Fukushima than in Chernobyl for the same 14 species, demonstrating a negative consequence of radiation for birds immediately after the accident on 11 March 2011 during the main breeding season in March–July, when individuals work close to their maximum sustainable level.
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