Accumulation Of 90Sr Research Articles

Monitoring of <sup>37</sup>C, <sup>90</sup>Sr and <sup>40</sup>Kin Sod-Podzolic Soils and Plants of Reference Sites of the Ivanovo Region

The results of radiation monitoring of sod-podzolic soils of reference agricultural plots of the Ivanovo region, conducted in 2014 and 2021, are presented. Background values of the specific activities of the studied radionuclides in the soils of reference sites have been established. According to the pollution density of the arable horizon of soils 137Cs and 90Sr, the level of the ecological situation was determined, which made it possible to attribute the soils of all reference areas of the region to uncontaminated territories suitable without restrictions for agricultural use. The power of the exposure dose of gamma radiation of soils and the contribution of 40K and 137Cs to the formation of the gamma background of soils were determined. Correlation analysis determined the influence of individual physical and chemical properties of soils on the behavior and distribution of radionuclides in the soil and the relationship between the content of the radionuclides themselves. Based on the values of the specific activity of 137Cs and 90Sr in plant products grown in 2014 and 2021, rows of cultivated plants with a decreasing ability to accumulate these radionuclides from the soil were constructed. All grown plant products of all types of crops fully met the veterinary standards required to limit the content of 137Cs and 90Sr in plant feeds (green mass, straw and feed grain). The coefficients of accumulation and transition of 137Cs and 90Sr from soil to plants are calculated. The coefficients of linear correlation between the values of the specific activity of 137Cs and 90Sr in soils and plants revealed the strength and nature of these dependencies.

Hygienic assessment of 90Sr and 137Cs contamination of water and fish in the lakes of the head part of the peripheral zone of the East Ural radioactive trace

Introduction. The article presents the results of studies of the specific activity of 90Sr and 137Cs in the water and fish of the Irtyash and Kazhakul lakes located in the peripheral zone of the head of the East Ural Radioactive trace in 2014-2017.
 Materials and methods. Determination of the levels of specific 90Sr and 137Cs in the water and the body of the resource-forming species of Siberian roach (soroga, chebak) Rutilus rutilus lacustris (Linnaeus, 1758) from the studied lakes was carried out over the period of 2012–2017. The measurements were carried out using standardized methods adopted in in the Federal State Budgetary Institution of Health “Central Medical and Sanitary Unit No. 71 of the Federal Medical and Biological Agency of Russia” (FGBUZ TsMSCH No. 71 of the Federal Medical and Biological Agency of Russia) and the Southern Ural.
 Results. The research was carried out over 2014 to 2017. Since the accident at the Mayak enterprise in the fall of 1957, the specific radioactivity of the water in the studied lakes was found to decrease. The concentration of 90Sr in the water of Irtyash lake was 0.019±0.008, and 137Cs – 0.028±0.009, and in Lake Kazhakul – 0.19±0.06 and 0.14±0.06, respectively. These values are much lower than the level of intervention according to NRB-99/2009. 
 The water of the lakes is used to meet household needs. The water of Lake Irtyash is used for drinking water supply of the city of Ozersk. The specific activity of the raw mass of a roach carcass from the Irtyash and Kazhakul lakes for the accumulation of 90Sr is 2.7± 1.7 and 64.5±19 and 137Cs – 1.68± 0.8 and 38±33.5Bq/kg, respectively. All the samples studied separately according to 90Sr and 137Cs had levels of radioactive contamination at or below the regulatory compliance indicator (SanPiN 2.3.2.1078–01). At the same time, taking into account the absolute extended uncertainty (with a coverage factor of k = 2) roach from Kazhakul lake has a significant excess of the limit level of radioactive contamination.
 Limitations. Hydrochemical parameters of the aquatic environment in various reservoirs can vary significantly over time and affect the accumulation of radionuclides by hydrobionts. Therefore, the research results are relevant only for the research period. To obtain more reliable results, long-term comprehensive monitoring is necessary.
 Conclusion. Over the past 60 years after the accident at the Mayak enterprise in 1957, the levels of radioactive contamination of water and fish in the studied lakes Irtyash and Kozhakul have decreased by more than 10 times. Calculation of doses of ionizing radiation for certain groups of the population of areas contaminated as a result of accidents, living near lakes, is a complex task, for which additional research is needed.

Accumulation of <sup>90</sup>SR in plant litter of fruit cenosis

The growth of industrial and agricultural production, against the backdrop of an increase in the population on the planet, requires an increasing amount of energy. Currently, quite a lot of options for its production are known: thermal and hydroelectric power plants, the use of solar energy (solar batteries), wind, etc. The nuclear power industry continues to develop at a fairly high pace. After the accidents at the Chernobyl nuclear power plant and in Japan, Fukushima 1, a wave of radiophobia rose around the world. But life is taking its toll, and nuclear power plants have already been built or are being built in Belarus, England, China, and so on. Reactors for nuclear power plants are being modernized, but there are no guarantees against accidents. In this case, pollution of various territories, including agricultural land, is possible. The performed scientific work makes a significant contribution to the solution of an urgent problem, i. e. the return of radioactively contaminated fertile lands to agricultural production. The purpose of the research is to study the migration and accumulation of 90Sr in the litter in the orchard, depending on the location of the nuclide in the soil. To achieve the goal of the research, the following tasks have been set: to determine the specific activity of the foliage, bark and wood of the apple tree for the research option with the surface location of the radionuclide on the soil; to determine the specific activity of the foliage, bark and wood of the apple tree for the research option with a buried location of the radionuclide in the soil by 50 cm. To solve the tasks, the field method was used, the radionuclide content in the plant was analyzed on the USK GAMMA Plus device with a beta tract. When the radionuclide is located in the upper part of the soil, the bark of the fruit plant will make the greatest contribution in terms of radiation, followed by leaves and wood. The greatest accumulation of the radionuclide in the second variant of the experiment occurred in the leaves. The difference in the specific activity of 90Sr between foliage and bark in 2016 was 2.0 times, between foliage and wood – 2.2 times. It was established that the studied variants of the experiment had an impact on the accumulation of the pollutant in the plant litter.

Хелатні комплекси мікроелементів кобальту, міді, марганцю, цинку як блокатори надходження радіонуклідів 90Sr, 137Cs в організм людини харчовим ланцюгом «ґрунт — рослина — тварина — людина»

The influence of chelated complexes of trace elements (Mn, Zn, Cu, Co) with ethylenediaminedisuccinic acid on reducing the accumulation of radionuclides 137Cs and 90Sr in plants and animals was studied. Foliar feeding of fodder plants (lupins, rapeseed, oats, clover, etc.) in the conditions of the Ukrainian Polissia on turf-podzolic soils contaminated with radionuclides, with aqueous solutions of complexonates of trace elements reduces the accumulation of 137Сs in the vegetative mass and grain by 1.6–2.8 times and 90Sr in 1.4–1.6 times. Compared with sulfates of microelements, complexonates have a much higher radio-blocking efficiency. Treatment of plants with microelement complexes increased the yield of vegetative mass and grain by 17–36 % and 16–38 %, respectively. At the same time, there is an improvement in their nutritional quality in plants, the content of some metabolites (crude protein, crude fat, crude fiber, sugars) increases by 30–35 %. Addition of zinc-manganese and cobalt-copper complexonates to the diet of cows in amounts compensating for the natural lack of trace elements led to a decrease in the accumulation of 90Sr and 137Cs in milk and meat by almost 2 times. At the same time, when using complexonates, an increase in the milk productivity of cows by 15–25 % and the content of fat, proteins, weighty components in the milk of cows, which characterize the quality of milk, by 2–3 % were noted. At the same time, some immune indicators of the animals increased: leukocytes — by 11 %, basophils — by 44 %, rod and segmented leukocytes — by 30 and 37 %, respectively, monocytes — by 43 %, which indicates an improvement in the state of their immune system. Probably, the effect of the use of complexonates is due to greater permeability of microelements through cell membranes and the ability to directly integrate into the molecular structures of enzymatic systems, bypassing many transport chains.

Influence of operation of thermal and fast reactors of the Beloyarsk NPP on the radioecological situation in the cooling pond: Part II, Macrophytes and fish

The influence of waste technological waters of thermal and fast reactors of Beloyarsk NPP (Russia) on the accumulation of 60Co, 90Sr and 137Cs in macrophytes and ichthyofauna of the cooling pond has been studied. Critical radionuclides, routes of their entry into the ecosystem and periods of maximum discharge of radioisotopes into the cooling pond have been determined. It is shown that the technology of electricity generation at the Beloyarsk NPP, based on fast reactors, has a much smaller effect on the release of artificial radionuclides into the environment. Therefore, during the entire period of monitoring studies (1976–2019), the decrease in the specific activity of radionuclides of NPP origin in macrophytes was 13–25800 times, in ichthyofauna 1.5-44.5 times. The maximum discharge of artificial radionuclides into the Beloyarsk reservoir was noted during the period of restoration and decontamination work aimed at eliminating the emergencies at the AMB reactors of NPP. The factors influencing the accumulation of artificial radionuclides in the components of the freshwater ecosystem of the Beloyarsk cooling pond have been determined, including: the physicochemical nature of radioisotopes, their concentration in surface water, the temperature of the aquatic environment, the trophicity of the reservoir, the species of hydrobionts.

Radiation monitoring of foodstuffs and drinking water in the vicinity of the Rooppur Nuclear Power Plant (People’s Republic of Bangladesh)

The system of radiation monitoring of local foodstuffs and drinking water in the settlements of the area of the Rooppur Nuclear Power Plant was developed. An analysis of the results of a 4-year (2014–2017) cycle of studies on the assessment of the specific activity of natural (40K, 226Ra, 232Th) and artificial (90Sr, 137Cs) radionuclides in the components of the diet of the population of the 30-km zone of influence of the nuclear power plant is presented. Thus, the specific activity of the most radiologically significant 137Cs in cow's milk averages 0.05 Bq.L−1, beef − 0.14, poultry − 0.09, and fish − 0.15 Bq.kg−1. In cereals, the 137Cs content varies in the range 0.2–0.6, vegetables 0.03–0.11, fruits 0.05–0.1 Bq.kg−1 and is determined by the species characteristics of crops. It was noted that 90Sr accumulates in food products to a greater extent than 137Cs. In livestock production, this difference is 1.2–6.8 times, fish 1.5 times, grain 1.2–4.2, vegetables 1.5–8.2, fruits 1.8–5.8 times. In drinking water, the specific activity of 137Cs is at the level of 0.05, 90Sr − 0.03, 3H − 1.3 Bq.L−1. The coefficients of accumulation of 90Sr and 137Cs in foodstuffs of animal and plant origin have been calculated.

Analysis of the <sup>90</sup>SR content in grassland vegetation when placed in leached chernozem

Nuclear power continues to develop rapidly in the 21st century. Due to the growth of the population on the planet and the growth of its well-being, more energy is required, which nuclear energy can also provide. Currently, work to improve the reactors used at nuclear power plants is going on. However, unfortunately, there are no guarantees for their trouble-free operation. Therefore, in case of possible accidents and radioactive contamination of the soil, the question arises of its further use in agricultural production. The return of radioactively contaminated fertile lands to agricultural production is the most important task at the present stage of human life. The purpose of the research is to study the content of specific activity in grassland vegetation, depending on its type, when the nuclide is located in the soil at a depth of 50 cm. The migration and accumulation of 90SR in grassland vegetation located in the orchard in the soil at a depth of 50 cm has been studied. The study of the accumulation of radionuclides in agricultural plants and soil after its radioactive contamination is one of the most urgent problems of our time. A field experiment has been carried out in a fruit seed orchard. Grassland vegetation is the most valuable bioresource, that is, it is a potential food for domestic and wild animals, so it is important to make a forecast of its possible use. Accumulation of the radionuclide in grassland vegetation along the trophic chain can lead to its accumulation in the human body. The largest accumulation of 90SR in annual herbaceous vegetation, as a possible fodder bioresource, when the radionuclide is located in the soil at a depth of 50 cm, is distinguished by field bindweed. In 2019, the difference in the accumulation of the nuclide between field bindweed and couch grass was 2.5 times. A decreasing series is compiled for the accumulation of the radionuclide, when it is located in the soil at a depth of 50 cm: field bindweed (Convolvulus arvensis L.) > field dandelion (Taraxacum officinale) = field sow thistle (Sonchus arvensis L.) > creeping couch grass (Agropyrum repens L.) > common yarrow (Achillea millefolium L.).

Accumulation of 90SR by Betula pendula within the East Ural Radioactive Trace zone

This study was conducted in 2010–2020 at the head of the East Ural Radioactive Trace (EURT), which was formed in 1957 as a result of the Kyshtym accident at the Mayak Production Association. The main contaminant in this zone is the long-lived radionuclide Strontium-90 (90Sr). Secondary forests dominated by silver birch (Betula pendula) occupy 45% of the EURT area. Concentration of 90Sr in birch leaves and small branches was higher than that in the trunks. The 90Sr content in birch sapwood varied slightly in the radial direction and did not depend on tree age. This was due to the dynamic equilibrium of the migration processes responsible for the accumulation and horizontal transfer of 90Sr. The 90Sr concentration increases in false heartwood, which is formed as a result of the secondary metabolism of dying parenchyma in the inner part of sapwood and is characterised by a high content of ash elements. The concentration of radionuclides in the aboveground organs of birch increased and the aggregated transfer factors (Tag) decreased with an increase in the soil contamination density, in accordance with the power function. The reasons for these patterns are also discussed.

Assessment of herb field mouse (Sylvaemus uralensis) migration in the area of the East Urals Radioactive Trace using measurements of bone-seeking 90Sr

The dynamics of rodent population in the area of East Urals Radioactive Trace (EURT) is one of the controversial issues, which are of key importance for the radiobiological and radioecological interpretation of the observed radiation effects. The objective of the paper is to evaluate the probability of migration in population of the herb field mouse (Sylvaemus uralensis Pall., 1811) based on 90Sr activity concentrations in the mouse bones. Radiometric data for bones of 768 mice captured at 9 sites in the EURT territory (with different environmental contamination levels) in 2001–2012 were used. The distribution of bone-seeking 90Sr in the juvenile age group of mice is used as a model of the width of radionuclide distribution in the bones of permanent inhabitants. Comparison of the model predictions and observations in different age and functional groups within the population structure allows simulating the probability of migration and evaluating the fraction of migrants. It is shown that the accumulation of 90Sr in bones correlates with soil contamination at the capture sites. Individual variability in the specific activity of 90Sr in the skeleton tends to increase with the age of animals. The rate of herb field mouse migration is estimated as 7 and 15% per year (for underyearlings and wintered individuals, respectively). The animals captured in the EURT area (all animals, including juvenile individuals) are “diluted” with animals from non-contaminated territories by 5–12%. The average half-time of substitution of the exposed population by migrants from non-contaminated territories is 8 years. Today, the fraction of descendants of the animals, that for generations have permanently inhabited the EURT territory since 1957, is negligible (on average-1.2% and not exceeding 17%). The proposed method of probabilistic analysis of 90Sr in the bones could be used to study migration activity of other species of rodents.

Growing giant miscanthus in Polissya on radioactively contaminated soils

Purpose. Investigate the accumulation of 137Cs and 90Sr radionuclides in the biomass of giant miscanthus depending on the agronomic methods of growing it on radioactively contaminated soils in Polissia.
 Method. Biomorphological, radiometric, lysometric, statistical, comparative and computational.
 Results. The article presents the results of research to study the accumulation of radionuclides 137Cs and 90Sr in the biomass of giant miscanthus. It was found that in the variants where the bioenergy crop was grown on soils contaminated with radionuclides, the accumulation of 137Cs in the biomass in the range of 14.7–18.6 Bq/kg and 90Sr — 0.46–0.54 Bq/kg was observed. The use of mineral fertilizers together with liming and inoculation with giant miscanthus with the microbial preparation Polymyxobacterin and treatment with organo-mineral fertilizer BioMAG helped to reduce the accumulation of radionuclides in the biomass of giant miscanthus as following: 90Sr — by 15% and 137Cs by 21%. It was investigated that the use of these agronomic techniques contributed to the formation of dry biomass yield at the level of 9.96 t/ha on average over three years of cultivation, which is 28% higher than the control.
 Conclusion. It is established that the use of mineral fertilization in combination with liming, inoculation of rhizomes of giant miscanthus with the microbial drug Polymyxobacterin and pre-planting treatment with organo-mineral fertilizer BioMAG contributes to a significant increase in dry biomass yield with reducing 90Sr and 137Cs. The accumulation of these radioactive isotopes in the biomass of giant miscanthus when grown on radionuclide-contaminated soils did not exceed the permissible level for cereal grains, and the use of agronomic techniques helped to reduce the content of 90Sr by 9–15% and 137Cs by 12–21% compared to control. The lowest coefficients of radionuclide conversion into biomass of giant miscanthus were obtained for both 90Sr (0.15) and 137Cs (0.24) for the use of mineral fertilizers together with liming and inoculation of giant mismanthus rizomes with Polymyxobacterin and treatment with BioMAG organo-mineral fertilizer.

The forecast accumulation in vegetative and generative organs of black currants and plum with 90Sr its location on the surface of the soil

As a result of field studies, experimental material on the accumulation of 90Sr in vegetative and generative organs of black currant and cherry plum in the link of the trophic chain «soil-plant» was obtained. Coefficients of transition (CT) from soil to bark, wood, leaves and fruits of black currant and coefficients of transition from soil to bark, wood, leaves and fruits of cherry plum which will allow to make the forecast of accumulation of radionuclide at any known density of pollution of the soil in the conditions of Krasnodar region on the studied soils are defined.

Growing giant miscanthus in Polissia on radioactively contaminated soils

Purpose. Investigate the accumulation of 137Cs and 90Sr radionuclides in the biomass of giant miscanthus depending on the agronomic methods of growing on radioactively contaminated soils in Polissia.
 Method. Biomorphological, radiometric, lysometric, statistical, comparative and computational.
 Results. The article presents the results of research to study the accumulation of radionuclides 137Cs and 90Sr in the biomass of giant miscanthus. It was found that in the variants where the bioenergy crop was grown on soils contaminated with radionuclides, the accumulation of 137Cs in the biomass in the range of 14.7–18.6 Bq/kg and 90Sr 0.46–0.54 Bq/kg was observed. The use of mineral fertilizers together with liming and inoculation of giant miscanthus with the microbial preparation Polymyxobacterin and treatment with organo-mineral fertilizer BioMAG helped to reduce the accumulation of radionuclides in the biomass of giant miscanthus, specifically 90Sr by 15% and 137Cs by 21%. It was investigated that the use of these agronomic techniques contributed to the formation of dry biomass yield at the level of 9.96 t/ha on average over three years of cultivation, which is 28% higher than the control.
 Conclusion. It was found that the use of mineral fertilization in combination with liming, inoculation of rhizomes of giant miscanthus with the microbial drug Polymyxobacterin and pre-planting treatment with organo-mineral fertilizer BioMAG contributes to a significant increase in dry biomass yield, reducing 90Sr and 137Cs. The accumulation of these radioactive isotopes in the biomass of giant miscanthus when grown on radionuclide-contaminated soils did not exceed the permissible level for cereal grains, and the use of agronomic techniques helped to reduce the content of 90Sr by 9–15% and 137Cs by 12–21% compared to controls. The lowest coefficients of radionuclide conversion into biomass of giant miscanthus were obtained for both 90Sr (0.15) and 137Cs (0.24) for the use of mineral fertilizers together with liming and inoculation of giant miscanthus rizomes with Polymyxobacterin and treatment with BioMAG organo-mineral fertilizer.

Assessment of the impact of the BN-800 reactor operation on the radionuclides content in local foodstuffs in the vicinity of Beloyarsk NPP

The research results are presented as an analysis of long-term data on the effect of gas-aerosol emissions and liquid discharges of Beloyarsk NPP and the Institute of Reactor Materials on the content of artificial radionuclides in local foodstuffs. It was noted that the distance and directions from radiation-hazardous facilities do not significantly affect the accumulation of 90Sr and 137Cs in potatoes and milk. The investigation of a wide range of foodstuffs from the private households of 23 settlements, forests, rivers, and a reservoir of the 30-km zone of the Beloyarsk NPP influence showed that the operation of the BN-800 reactor since 2016 did not lead to a registered increase in the content of artificial radionuclides in agricultural and natural foodstuffs. The maximum specific activities of 90Sr (0.84 Bq/kg) and 137Cs (0.26 Bq/kg) in root vegetables, potatoes, melons and vegetables were noted before the start of operation of the new power unit and were 45 and 300 times, respectively, lower than the current SanPiN standards. The highest content of 90Sr in milk (0.41 Bq/l) was 60 times lower than the requirements of SanPiN, 137Cs (0.11 Bq/l) was 900 times less than the permissible levels. In poultry, the specific activity of 90Sr (0.2-0.3 Bq/kg) and 137Cs (0.13-0.16 Bq/kg) has remained stable low in recent years, and the standardised content of 137Cs in beef (maximum 0.12 Bq/kg) more than 1.5 thousand times lower than the requirements of SanPiN. The highest concentration of 137Cs in wild berries, found in strawberries (1.27 Bq/kg), was 125 times less than SanPiN standards. The content of 90Sr in mushrooms was at the level of 0.1-2.5 Bq/kg, the content of 137Cs is slightly higher than - 0.6-5.8 Bq/kg. The maximum recorded specific activity of 137Cs in mushrooms was more than 80 times lower than the requirements of SanPiN. During the observation period, a decrease of up to 20% or more in the content of artificial radionuclides in samples of 5 fish species was noted; the maximum levels of 90Sr and 137Cs in it were 14 times lower than the strictest SanPiN standards (using fish for baby food). Selective radiation monitoring of foodstuffs of Beloyarsk NPP area aimed at 3H and 14C showed that the content of these radionuclides in foodstuffs was low, close to the background level. In agricultural products, 3H and 14C accumulated to a greater extent in potatoes and milk, and in natural products – in rough boletus and bream. There was noted a need to continue research on the accumulation of 3H and 14C in foodstuffs of Beloyarsk NPP vicinity.

Accumulation and distribution of radionuclides in higher aquatic plants during the vegetation period

The long-term observations of the dynamics of 90Sr and 137Cs concentration, as well as the physicochemical forms of these radionuclides in 10 species of higher aquatic plants during the vegetation period of Glyboke Lake in the Chornobyl Exclusion Zone were presented. The accumulation of radionuclides depends on the influence of environmental factors and species characteristics of the studied plants. It has been shown that the accumulation of 90Sr and 137Cs by plants mainly occurs in accordance with the physiological stages of their development. Under conditions of intensive growth and accumulation of biomass in the juvenile period, plants disproportionately uptake 137Cs from the environment; during the seed ripening period at the stage of aging, plants mainly accumulate 90Sr, as evidenced by the non-correlation of this radionuclide concentration in water and plants in the considered periods. The specific features of the accumulation of radionuclides by plants were studied by the method of analysis of physicochemical forms, which consists in the sequential extraction of radionuclides from plant preparations and makes it possible to quantitatively investigate potentially exchange and fixed forms. The analysis of physicochemical forms confirmed the patterns of seasonal distribution of radionuclides, as well as their accumulation in cells, tissues and in the whole plant obtained from long-term observations.

DISTRIBUTION OF ARTIFICIAL RADIONUCLIDES IN AGGREGATE FRACTIONS OF SOILS IN THE VICINITY OF UNDERGROUND NUCLEAR TESTS CONDCUTED IN BOREHOLES AT “BALAPAN” SITE

The paper provides findings on distribution of artificial radionuclides in aggregate fractions of soils in radioactive fallout plumes near two Boreholes – 1301 and 1077 (the former ‘Balapan’ testing area), in which underground nuclear tests were conducted that differed in the nature of the real radiological situation. In the vicinity of Borehole 1301 in which an underground nuclear explosion was accompanied by the unforeseen release of debris into the atmosphere, the highest accumulation of 137Cs and 90Sr occurs in 250 to 1,000 µm fractions. Distribution of 241Am and 239+240Pu is characterized by two different tendencies – the predominant enrichment of 250 to 1,000 µm fractions in the near zone of the plume (up to 250 m) and predominantly enriched fractions of 5–8 µm and <1 µm in the distant plume area (700 to 2,500 m). Near Borehole 1077, near which the underground explosion is assumed to have been accompanied by escaping radioactive inert gases, 137Cs and 90Sr are mainly concentrated in less than 5 µm fractions, 241Am and 239+240Pu – in fractions of 8–40 µm and <1 µm.

Рівні вмісту дозоформуючих радіонуклідів у молоді окуня (Perca fluviatilis) Запорізького водосховища

It had been investigated the content levels and the coefficients of accumulation from water of the main dose-forming radionuclides (137Cs, 90Sr, 226Ra, 232Th, 40К) in different-age Perca fluviatilis from the Samara Bay and the lower part of the Zaporizke Reservoir. The three age groups of fish were used: one-summer old (0+), two summers old (1+), and three summers old (2+). The obtained data on consecutive reduction of radionuclide activity values in juvenile perch showed that maximal 137Cs content was found in individuals of age (0+), and the minimal one – in individuals aged (1+) from Samara Bay. The maximal accumulation of radioisotopes 90Sr was in individuals aged (0+) in the lower part of the Zaporizke Reservoir, and the minimal one in the perch of age (1+) in the Samara Bay. The highest levels of 226Ra and 40K were found in the (0+) fish from the Samara Bay, and the lowest contents were in individuals aged (2+) in the lower part of the reservoir. The value of the 232Th content level was maximal in the two-summer-olds from the lower part of the reservoir, and the minimal one – in (0+) fish from the Samara Bay. Artificial radionuclide 137Cs was accumulated in the largest amount by perch (0+) from the Samara Bay, and 90Sr – by fish from the lower part of the Zaporizke Reservoir. By values of accumulation coefficients, 232Th was in second place after 137Cs, indicating its significant contribution to the formation of the total dose of radiation. Majority of radioisotopes investigated were more intensively accumulated by the juvenile perch in the Samara Bay compared to the lower part of the Zaporizke Reservoir. The highest level of radionuclide accumulation at both studied sites of the Zaporizke Reservoir has been observed in (0+) fish.

Агроекологічна ефективність елементів технології вирощування міскантусу на радіоактивно забруднених ґрунтах

The purpose. To study accumulation of 137Cs and 90Sr in biomass and lysimetric waters and to determine agroecological efficiency of elements of technique of growing Miscanthus large on the soils contaminated with radioactive substances. Methods. Lysimetric, biomorphological, radiometric, statistical, comparative-calculation. Results. Data on accumulation of radioisotopes in biomass of Miscanthus large and lysimetric waters are cited. It is established that the level of accumulation of radioactive nuclides in plants of Miscanthus on the low-purity soils depends on elements of technique of growing, radioisotope and its density in soil. It is established that in alternatives where biopower crop was cultivated on soils contaminated with radioactive nuclides, accumulation in biomass of 137Cs made 14,7–18,6, 90Sr — 0,46–0,54 Bq/kg, in lysimetric waters — 4,36–4,57 and 0,28–0,65 Bq/l accordingly. Importation of fertilizers together with defecate and treatment of Miscanthus rhizomes before planting with microbial preparation Polimiksobakterin together with BioMAG promoted 28% increase of yield of dry biomass as compared to control. Conclusions. Application of fertilizers in a complex with chalking, inoculation of Miscanthus rhizomes with microbial preparation Polimiksobakterin and pre-sowing treatment with organomineral fertilizer BioMAG promoted essential increase of yield of dry biomass, decrease of 137Cs and 90Sr in biomass and lysimetric waters. Accumulation of these radioisotopes in Miscanthus biomass at growing on soils contaminated by radioactive nuclides did not exceed allowable level, and application of elements of technique promoted lowering content of 137Cs on 12–21%, 90Sr — on 9–15% as compared to control alternatives. At use of fertilizer complex «mineral fertilizer + defecate + Polimiksobakterin + BioMAG» they gained the least accumulation coefficients in Miscanthus biomass (137Cs — 0,07, 90Sr — 0,05), and in lysimetric waters (137Cs — 0,02, 90Sr — 0,03 ).

Eco-phytomonitoring in ensuring radiological safety of urban buildings

In the future, the use of nuclear energy in national economy will rise. After accident at the Chernobyl nuclear power plant, staff of Fukushima 1 pay special attention to the safety of reactors, however, emergency situations are still possible. Eco-monitoring in natural and urban environments is carried out in order to determine the level of ecological pollution, including radioactive pollution. Therefore, studies in that direction are relevant and their relevancy is only increasing over the years. The aim of this study is to research migration and accumulation of 90Sr in vegetative and generative plant organs: cherry-plum (Prunus cerasifera Ehrh) tree and stone fruit species, gooseberry (Ribes uva-crispa) shrub. Objectives: 1) applying 90SrCl2 to the soil, imitating precipation (field experiments); 2) planting: Prunus cerasifera Ehrh; Ribes uva-crispa into artificially polluted by 90SrCl2 soil; 3) growing and monitoring of studied plants in the artificially polluted by 90SrCl2 soil. The level of pollution of experiment field reached 500 MBq/m2. The accumulation of 90Sr in vegetative and generative organs of trees (Prunus cerasifera Ehrh) and shrubs (Ribes uva-crispa) was researched. Experimental plots have been laid according to methodic of Dospekhov B.A. Measurements of beta-emitting nuclides activity in samples have been made using the “Progress” software on the USK “Gamma Plus” (beta-path) device. As the result of research it has been found that both plant species have been accumulating nuclides. In 2016 cherry-plum accumulated 90Sr in the bark, wood, leaves and fruits 2.0, 2.1, 2.6 and 2.6 times more accordingly than the gooseberry. As a result of the experiment, material, that can be used in eco-monitoring, was obtained to provide nuclear safety of urban properties in the territories, allocated for the construction of public and residential buildings.

Environmental monitoring and urban phytodesign in ensuring the radioecological safety of urban buildings

The purpose of this paper is to study the migration and accumulation of 90Sr in vegetative and generative organs of plants: golden currant (Ribes aureum) and cherry plum (Prunus cerasifera Ehrh). Research objectives: 1) 90SrCl2 is artificially deposited on the soil, precipitation imitation (field experiments); 2) planting plants: Prunus cerasifera Ehrh and Ribes aureum to the soil artificially contaminated with 90SrCl2; 3) cultivation and monitoring of the studied plants in the soil artificially contaminated with 90SrCl2. The contamination level of the experimental area was 500 MBq/m2. The possibilities of tree and shrub plant forms (Prunus cerasifera Ehrh; Ribes aureum) to accumulate 90Sr in their vegetative and generative organs were studied. The activity of the beta-emitting radionuclide in the counting samples was measured using the “Progress” software on the Multi-purpose spectrometric complex “Gamma Plus” device (beta path). As a result of research, the accumulation of radionuclides in both studied plants was found. In 2016, the difference in the content of 90Sr between cherry plum and golden currant in bark, wood, leaves, and fruits was 1.6, 1.5, 1.8, and 2.0 times, respectively. Experimental data can be used in the environmental monitoring of the radiation situation in urban areas of the territories allocated for the construction of public, residential buildings and structures, to be the basis for further advanced research in the designated area.

Estimation of 137Cs and 90Sr accumulation in the organism of dairy cows in the radioactive contaminated agro landscapes of the Central Forest-steppe in the remote period of the Chernobyl catastrophe

Because of the Chernobyl catastrophe, almost all the territory of Polissya and a significant part of the Forest-Steppe south of Kyiv suffered radioactive contamination. More than three decades have passed since the Chernobyl accident, but despite the time since the disaster, the problem of radioactive contamination is still very relevant. In radioactive contaminated agro landscapes, plant fodder becomes a source of 137Cs and 90Sr in the body of cows. In the organism of an animal, radionuclides of cesium mainly accumulate in muscle tissue, and strontium in bone and excreted with milk, urine and feces. Milk plays an important role in human nutrition, which necessitates constant monitoring of the radio ecological situation, estimates of the accumulation of 137Cs and 90Sr, and the determination of the laws governing the transition of these radionuclides into products. The aim of the research was to evaluate the supply of 137Cs and 90Sr with feed in the body of dairy cows and the accumulation of these radionuclides in milk and barnyard manure mass in radioactive contaminated agricultural landscapes of the Central Forest Steppe. The research was carried out at LLC "Agro-Leader Ukraine" Ltd. and "Nadiya" Ltd and on the peasants’ plots of Yosypivka, Tarasivka villages of the Bila Tserkva district of the Kyiv region who suffered from the radioactive contamination because of the Chernobyl catastrophe. Samples of soils, fodder, milk and barnyard manure mass for conducting research were selected. The activity of 137Cs and 90Sr was determined at the USM "Gamma Plus U" with the "Progress 2000" software in the laboratory of the Bila Tserkva NAU, department of life safety. The activity of 137Cs was determined by the method of scintillation gamma spectrometry in a Marinelli vessel of volume 1L in native samples or after their physical concentration, and 90Sr – after radiochemical isolation by scintillation beta spectrometry. The results of the studies indicate that the content of 137Cs and 90Sr in feed is directly proportional to the level of soil contamination by these radionuclides. At the same time, the least accumulated 137Cs and 90Sr in the green mass of corn, and most of all in the green mass of alfalfa and oats mixture. The intensity of the accumulation of 90Sr in the green mass of corn is 20 times, the alfalfa – in 1,5-2 times, the use of oatmeal mixture – 4 to 6 times higher than 137Cs. It has been established that the concentration of 137Cs and 90Sr in milk of cows is directly proportional to their activity in the diet. In the daily hopes of milk from cows from the diet 7,6 ± 0,55 % of 137Cs and 1,7 ± 0,42 90Sr passed from their activity in the diet. The coefficient of transition of 137Cs in 1 liter of milk on average was 0.76 % and 0.17 % 90Sr. The activity of 137Cs and 90Sr in milk does not exceed the permissible levels. At the same time, in the milk of households, the activity of 137Cs and 90Sr in the spring-summer period was two to three times higher than that of autumn-winter due to the grazing of cows in natural pastures, where the level of soil contamination is much higher than that of arable lands. The determinants of the formation of 137Cs and 90Sr activity in cow’s milk are the amounts of these radionuclides with feed from the daily ration, which depend on the composition of the diet and the density of soil contamination on which the forage crops are grown. Studies have shown that the main proportion of 137Cs and 90Sr (up to 90 %), coming from plant foods in the body of cows, is converted into a barnyard manure mass. The accumulation coefficient of 137Cs and 90Sr in the cow barnyard manure is 0.87. The barnyard manure mass of cows, when introduced into the soil, becomes a source of secondary soil contamination and promotes the migration and redistribution of 137Cs and 90Sr in agro landscapes. Obtained in radioactive contaminated areas of the barnyard manure mass of cattle must be used only within the farms in which it is produced. Studies have shown that fodder crops can be grown on the radioactive contaminated forest-steppe areas and it is possible to get milk without any restrictions. Key words: agro landscapes,radioactive contaminated areas, radionuclides, 137Cs, 90Sr, grass, dairy cows, milk, cow’s manure, forest-steppe zone.