Specific Activity Of 137Cs Research Articles

The effect of tree roots on the redistribution of 137Cs in the soils of pine and birch forests of the radioactive contamination zone

Accumulation and distribution of 137Cs by the root systems of forests in the radioactive contamination zone of Bryansk oblast have been discussed. It has been found that the phytomass and distribution of roots of pine and birch trees along the soil profile in the studied BGCs differ considerably. The specific activity of 137Cs in the roots changes depending on their diameter: the lowest specific activity is observed in small fractions of the roots, and the highest one in large fractions. It has been shown that the contribution of roots in the total reserves of 137Cs in the soil layer of 0–50 cm of various biogeocenoses is different: the largest contribution is characteristic for birch forests (1.66%) with variation of this parameter in separate soil layers from 1.12 to 3.53%, while the contribution for pine forests is lower (0.97%) with the variation from 0.82 to 7.5%. The contribution of roots to the overall contamination of soils in the studied plant communities increases with depth.

Assessment of current radiological situation in the mea dows of Zhytomyr region

According to the results of monitoring studies we determined the level of radioactive contamination of major crops produced for self-consumption in private households in the contaminated area of the northern districts of Zhytomyr region. Monitoring studies we conducted at the Institute of Agriculture Polesie NAAS on the farm area in II–IV zones of radioactive contamination at the sod-podzolic and peat soils. We used data on radiological monitoring in the farms of the northern districts of Zhytomyr region and contaminated milk and the main types of agricultural products («green» products, vegetables, forest products) produced by private households. Toward Integrated Monitoring studies we conducted observations at fixed points (PT) on grassland. It witnessed a high density and diversity of contamination within the studied area (1.0–15.1 Ci/km2 ) and the specific activity of 137Cs (82–308 Bq/kg) in plants of fodder crops and grassland vegetation (60–337 on sod-podzolic and 612 Bq/kg of peat soils air-dry weight). In some areas the level of 137Cs contamination can reach 721–3376 Bq kg (6–27 Ci/km2). According to monitoring results for certain types of agricultural production in the private sector, it was found that the excess of the allowable level (100 Bq/kg), the specific activity of 137Cs in milk (according to the DR-2006) on the grazing period is not noted, but the increase in internal radiation dose of a human body is due to their high content (59–79 Bq/kg). The activity of 137Cs in leafy greens varied depending on the type of vegetable production and location selection within 43–179 Bq/kg, and in the forest products (Korosten district) in the forests around individual settlements it reaches 2463–9587 Bq/kg, exceeding the DR-2006 5–19 times.

137Cs specific activity in pork under using different doses of protein-vitamin-mineral supplements in the diet of animals

The recipes of grain mixtures are developed for fattening of sapling of pigs in III area of radiocontamination with plugging in their composition of different doses of BVMD and highly albuminous forage of local production : І group (control) — grain mixture № 1 (20% on mass of a albumen-vitamin-mineral additive); ІІ group (skilled) — grain mixture № 2 (10% BVMD + 10 % grain of Austrian winter pea); ІІІ group (skilled) — grain mixture № 3 (10% BVMD + 10% grain of lupine). It is set that at substituting in composition of grain mixtures 10% of albumen-vitamin-mineral addition by the analogical amount of destroyed grain of Austrian winter pea (II experimental group) and destroyed grain of lupine (III experimental group) specific activity of 137Cs in muscular fabric, liver and fat in relation to control rises, accordingly, on 6.1–32.8%, 23.6–27.0 and 3.1–11.2%. Frequency rate of accumulation of radio cesium in production was much less among animals of І (control) group, which were fed with grain mixture with the maximum quantity of albumen-vitamin-mineral additive (20% on mass) — 0.274–0.347.

Features of radioactive contamination of agroecosystems of Ukrainian Polissya in the remote period after the accident on Chernobyl Nuclear Power Plant

The assessment materials of pollution features of agro-ecosystems of Ukrainian Polissya in the remote period after the accident are described in the article. It is shown that the main factors of influence on the flow of 137Cs from soil of contaminated agricultural land during a distant period do not differ from the previous period factors. It was found that current levels of 137Cs specific activity in soils of agrocenosis almost two and more times less than in the natural plant phytocenosis. The depth of massive infiltration of 137Cs in soils of arable land is much greater than in virgin soils, and almost completely determined by the process of root transfer and working capacity of the reservoir, which varies in the area of research from 10 cm to 30 cm. Despite the significant pollution of soil, the level of contamination of agricultural production is relatively low and does not exceed the permissible levels of radionuclides (DR-2006). Thus the highest rate of 137Cs transfer is noticed from soil to products of natural lands (0.06–0.66) and depends n the season and type of land.

Complexonates microelements effect on specific activity of 137Cs in cow’s milk

In the period of 2008–2011 four scientific-industrial experiments have been conducted. The paper researches the results related to the effect of different complexonates microelements on 137Cs passing out of the dairy cow diet into the milk. It has been stated that the application of complexonates microelements of copper, medium, manganese, zink into the cow’s diet facilitates the decrease of milk specific activity in 1.4 times. The application of complexonates microelements of zink, manganese, copper, iodine facilitated the decrease 137Cs specific activity in milk in 1.3–2.0 times.

Transfer factors for the „soil-cereals” system in the region of Pcinja, Serbia

The aim of the paper was to estimate the values of transfer factors for natural radionuclides (40K, 226Ra, 232Th, 235U, and 238U) and 137Cs from soil to plants (cereals: wheat, corn and barley) as important parameters for the agricultures in the selection of the location and the sort of cereals to be planted on. The results presented in this paper refer to the ?soil-cereals? system in the region of Pcinja, Serbia. Total of 9 samples of soil and 7 samples of cereals were measured in the Department of Radiation and Environmental Protection, Vinca Institute of Nuclear Sciences, using three high-purity germanium detectors for gamma spectrometry measurements. In all the samples, transfer factors for 226Ra are significantly lower than for 40K, but they are all in good agreement with the literature data. On the three investigated locations, the calculated values of transfer factors for 40K were in the range of 0.144 to 0.392, while in the case of 226Ra, the transfer factors ranged from 0.008 to 0.074. Only one value (0.051) was obtained for transfer factor of 232Th. Specific activities of 137Cs, as well as uranium isotopes, in all the investigated cereal samples, were below minimal detectable activity concentrations. Also, the absorbed dose rate and the annual absorbed dose from the natural radionuclides in the soil, were calculated. The absorbed dose rate ranged from 49-86 nSv/h, while the annual absorbed dose ranged from 0.061-0.105 mSv. The measurements presented in this manuscript are the first to be conducted in the region of Pcinja, thus providing the results that can be used as a baseline for future measurements and monitoring.

The influence of biotic and abiotic factors on 137Cs accumulation in higher fungi after the accident at Chernobyl NPP

Levels of soil contamination with 137Cs, the belonging of fungi to a certain ecological group, the localization depth of the main part of mycelium in soil are the primary factors influencing the value of 137Cs specific activity in higher fungi after the accident at Chernobyl NPP. It has been found that the value of 137Cs specific activity in fungi of one species could vary by more than 10 times during a vegetation period. A correlation between the changes of 137Cs content in fungi during the vegetation period and the amount of precipitates during various periods preceding the collection of samples has not been determined. An assumption has been proposed stating dependence between peculiarities of mycelium growth during the vegetation period and the changes of 137Cs specific activity in fungi.

Динаміка вмісту 137Cs у компонентах раціону диких ратичних тварин у лісах Житомирського Полісся

Наведено результати визначення питомої активності 137Cs у тих частинах деревних порід, чагарників, чагарничків і грибів, які є основним кормом для козулі європейської у лісах Житомирського Полісся. Визначено основні «критичні» періоди протягом року, які характеризуються найвищими рівнями вмісту радіонуклідів у кормах і в організмах дикого кабана і козулі європейської. Для всіх досліджуваних видів рослин, що входять до складу раціонів дикого кабана та козулі європейської, характерні значні сезонні коливання концентрації 137Сs у різних органах рослини, які можуть використовувати як корм тварини (коренях, річних пагонах, листі), а також у частинах органів (верхня, середня та нижня частини пагона). В осінній та весняний періоди виявлено підвищену концентрацію 137Сs у верхівках пагонів та коренях рослин. Влітку найбільшу активність 137Сs зафіксовано у надземній фітомасі. Представлено сезонні коефіцієнти переходу 137Cs з ґрунту в корма дикого кабана та козулі європейської у «критичні» періоди радіоактивного забруднення їх організмів. Запропоновано заходи щодо оптимізації термінів відстрілу диких ратичних тварин.

Distribution of global fallouts cesium-137 in taiga and tundra catenae at the Ob River basin

The classification of soil catenae at the Ob River basin is developed and applied. This classification reflects the diverse geochemical conditions that led to the formation of certain soil bodies, their combinations and the migration fields of chemical elements. The soil and geochemical diversity of the Ob River basin catenae was analyzed. The vertical and lateral distribution of global fallouts cesium-137 was studied using the example of the four most common catenae types in Western Siberia tundra and taiga. In landscapes of dwarf birches and dark coniferous forests on gleysols, cryosols, podzols, and cryic-stagnosols, the highest 137Cs activity density and specific activity are characteristic of the upper soil layer of over 30% ash, while the moss-grass-shrub cover is characterized by low 137Cs activity density and specific activity. In landscapes of dwarf birches and pine woods on podzols, the maximum specific activity of cesium-137 is typical for moss-grass-shrub cover, while the maximum reserves are concentrated in the upper soil layer of over 30% ash. Bog landscapes and moss-grass-shrub cover are characterized by a minimum activity of 137Cs, and its reserves in soil generally decrease exponentially with depth. The cesium-137 penetration depth increases in oligotrophic histosols from northern to middle taiga landscapes from 10–15 to 40 cm. 137Cs is accumulated in oligotrophic histosols for increases in pH from 3.3 to 4.0 and in concretionary interlayers of pisoplinthic-cryic-histic-stagnosols. Cryogenic movement, on the one hand, leads to burying organic layers enriched in 137Cs and, on the other hand, to deducing specific activity when mixed with low-active material from lower soil layers.

Pollution dynamics of different components of forest ecosystems with 137Cs in Bryansk, woodlands

The features in the redistribution of 137Cs and its chemical analog 39K in the structures of the main forest forming tree species (pine and birch) of Bryansk’s woodlands in the remote period after the Chernobyl fallout are considered. The dynamics of the specific activity of 137Cs in these structures is analyzed. Some differences in the redistribution of 137Cs and 39K in the components of pine and birch, as well as their long-term dynamics, were revealed.

C9,t11-Conjugated linoleic acid ameliorates steatosis by modulating mitochondrial uncoupling and Nrf2 pathway

Oxidative stress, hepatic steatosis, and mitochondrial dysfunction are key pathophysiological features of nonalcoholic fatty liver disease. A conjugated linoleic acid (CLA) mixture of cis9,trans11 (9,11-CLA) and trans10,cis12 (10,12-CLA) isomers enhanced the antioxidant/detoxifying mechanism via the activation of nuclear factor E2-related factor-2 (Nrf2) and improved mitochondrial function, but less is known about the actions of specific isomers. The differential ability of individual CLA isomers to modulate these pathways was explored in Wistar rats fed for 4 weeks with a lard-based high-fat diet (L) or with control diet (CD), and, within each dietary treatment, two subgroups were daily administered with 9,11-CLA or 10,12-CLA (30 mg/day). The 9,11-CLA, but not 10,12-CLA, supplementation to CD rats improves the GSH/GSSG ratio in the liver, mitochondrial functions, and Nrf2 activity. Histological examination reveals a reduction of steatosis in L-fed rats supplemented with both CLA isomers, but 9,11-CLA downregulated plasma concentrations of proinflammatory markers, mitochondrial dysfunction, and oxidative stress markers in liver more efficiently than in 10,12-CLA treatment. The present study demonstrates the higher protective effect of 9,11-CLA against diet-induced pro-oxidant and proinflammatory signs and suggests that these effects are determined, at least in part, by its ability to activate the Nrf2 pathway and to improve the mitochondrial functioning and biogenesis.

Application of PIXE analysis to investigation of plants cultivated with contaminated soil of Fukushima

We present a method to research low radioactive cesium contaminated plants by the use of PIXE analysis. Highly contaminated regions still remain in the Fukushima prefecture. We collected wild plants growing in this area, that is, Butterbur, Welsh onion, Alpine leek and White clover and measured their specific activities of 137Cs and 40K. We also measured 137Cs and 40K specific activities of soil under these plants. Soil-to-plant transfer factors of 137Cs were ∼0.02 for 4 wild plants and those of 40K were ∼0.5 except for White clover. Using PIXE analysis, we measured the concentration of mineral elements in these plants. Among mineral elements, we noted the concentrations of additional alkali metal elements such as Na, K and Rb. The experimental results showed that the concentration of Rb was proportional to the specific activities of 137Cs except for Welsh onion and other elements had no strong correlation with 137Cs. These results indicate that there may be correlations between the adsorption of Cs and Rb.

Spatial variability of 137Cs in the soil of Belgrade region (Serbia)

Among radionuclides in the soil deposited after Chernobyl accident, 137Cs poses considerable environmental and radiological problems because of its relatively long half-life (30.17 y), its abundance in the fallout, high mobility and similarity to potassium as the major plant nutrient. In this study the samples of undisturbed surface soil (n=250) were taken from 70 regions in Belgrade, during 2006-2010. The specific activities of 137Cs were measured by gamma-ray spectrometry. Based on obtained results external effective dose rates were calculated according to the internationally accepted activity to dose rate conversion equations. The specific activities of 137Cs were geographically mapped. The presence of 137Cs has been detected in all soil samples, with high variability of its specific activity, ranging from 3 Bq kg-1 to 87 Bq kg-1. The mean specific activity of 137Cs was 23 Bq kg-1 and the corresponding absorbed dose was 1.5 nSv h-1. The observed range reflects the inhomogeneity of the deposition process following the Chernobyl accident. It could also be attributed to topographic differences and spatial differences in physicochemical and biological soil properties, soil type and vegetation cover. The results of the present study could be valuable database for future estimations of the impact of radioactive pollution.

Neural networks in analysing 137Cs behaviour in the air in the Belgrade area

The application of the principal component analysis and artificial neural network method in forecasting 137Cs behaviour in the air as the function of meteorological parameters is presented. The model was optimized and tested using 137Cs specific activities obtained by standard gamma-ray spectrometric analysis of air samples collected in Belgrade (Serbia) during 2009-2011 and meteorological data for the same period. Low correlation (r = 0.20) between experimental values of 137Cs specific activities and those predicted by artificial neural network was obtained. This suggests that artificial neural network in the case of prediction of 137Cs specific activity, using temperature, insolation, and global Sun warming does not perform well, which can be explained by the relative independence of 137Cs specific activity of particular meteorological parameters and not by the ineffectiveness of artificial neural network in relating these parameters in general.

Dynamics of 137Cs Specific Activity in Fishes Differing in the Type of Their Nutrition in the Cooling Pond of the Chernobyl NPS (1986-2013)

Dynamics of 137Cs Specific Activity in Fishes Differing in the Type of Their Nutrition in the Cooling Pond of the Chernobyl NPS (1986-2013)

Specific Activity and Radioactive Contour Map of Anthropogenic Radionuclide (<sup>137</sup>Cs) in Surface Soil Samples from Chumphon Province, Thailand

Specific activities of anthropogenic radionuclide (137Cs) were studied and determined in 132 surface soil samples collected from 8 districts in Chumphon province in the south of Thailand. A high resolution high-purity germanium (HPGe) detector with a massive lead shield and gamma spectrometry analysis system were employed to measure the gamma ray energy spectra from the samples. The specific activity of 137Cs in all of surface soil samples were analyzed by using the IAEA/SL-2 radioactive standard source. It was found that the specific activities of 137Cs ranged from < 0.33 4.43 Bq/kg with mean values of 2.30 ± 1.38 Bq/kg. The experimental results were also compared with research data in the south of Thailand (2009 2012), Office of Atoms for Peace (OAP) annual report data and global radioactivity measurement and evaluations. The data can be also used to create the radioactive contour maps of the investigated area.

The modern radioecological situation at the Globus-1 site

This article is dedicated to analysis of the modern radioecological situation at the site of the Globus-1 peaceful nuclear explosion in the Ivanovo region. The variability of the ionizing radiation background, specific activity of 137Cs and 90Sr in the 0–20 cm soil layer, and dominant species of meadow vegetation near the site of the explosion are presented. Higher levels of 90Sr contamination of plants in this territory and water from a research well were determined. The indices of contamination of the meadow biogeocoenosis components according to 137Cs did not exceed the established norms.

134Cs and 137Cs radioactivity in soil and moss samples of Jeju Island after Fukushima nuclear reactor accident

Specific activities of 134Cs and 137Cs in surface soil and moss samples were investigated at 12 locations of Jeju Island, Korea. Specific activities of 134Cs and 137Cs in the surface soil vary from less than MDA to 17Bq/kg and from 12Bq/kg to 109Bq/kg, respectively. Specific activities of 134Cs and 137Cs in moss samples lie in the range 6Bq/kg–39Bq/kg and 15Bq/kg–41Bq/kg, respectively. The activity ratios 134Cs/137Cs in the soil samples are much less than the reference value of about 1.0, but they are close to 1.0 in the moss samples. Average amount of 137Cs added to the surface soil after the Fukushima accident is estimated to be 7.8±1.7Bq/kg. The depth profile of 137Cs specific activity has a lognormal shape with a peak between 5cm and 7.5cm below the ground. For the cored soil sample, 134Cs was detected up to 3cm below the ground.

Radiation Monitoring of the Surface Waters of the Kyiv Region

Quality of the surface waters of the Kyiv region has been assessed by three radiation safety indices: total β-activity, specific activity of 137Cs and 90Sr. Content of 137Cs and 90Sr in terms of total β-activity in water of the Desna River, Kiev reservoir and river section of the Kaniv reservoir have been determined. Data of previous studies have been confirmed: surface water of the Dnieper basin within zone of extensive radioecological control of the Kiev region can be used as a source of drinking and irrigation water according to actual sanitation regulations.

Specific activities and radioactive contour maps of natural and anthropogenic radionuclides in beach sand samples (Patong, Kamala, Kata, Karon and Nai Yang) after tsunami disaster in Phuket province, Thailand

Specific activities of natural (40K, 226Ra and 232Th) and anthropogenic (137Cs) radionuclides in 155 beach sand samples collected from Patong, Kamala, Kata, Karon and Nai Yang beaches, which were affected by the 2004 tsunami disaster, in Phuket province, Thailand, have been studied and measured. Experimental results were obtained by using a high-purity germanium detector and gamma spectrometry analysis system. Gamma ray from radioactive standard sources Cesium-137 (137Cs), Cobalt-60 (60Co) and Barium-133 (133Ba) were used to calibrate the measurement system. KCl, two well-known (IAEA/RGU-1 and IAEA/RGTh-1) and IAEA/SL-2 reference materials obtained from the International Atomic Energy Agency were used to analyze and compute the 40K, 226Ra,232Th and 137Cs specific activities in samples from five beaches. The measuring time of each sample is 10,800 s. It was found that the average specific activity of 40K in these areas (2459.14 ± 171.71 Bq/kg) was rather high. Furthermore, the results were also used to evaluate the absorbed dose rates in air (D), the radium equivalent (Raeq), the external hazard index (Hex) and the annual effective dose rate (AEDout) in all beach areas. Moreover, experimental results were compared with the Office of Atoms for Peace research data, Thailand as well as with global radioactivity measurements and evaluations. All of the calculated values (40K, 226Ra, 232Th and 137Cs) were also compared with the recommended values which were proposed by the Organization for Economic Cooperation and Development (Exposure to radiation from natural radioactivity in building materials, 1979) and United Nations Scientific Committee on the Effects of Atomic Radiation (Sources, effects and risk of ionizing radiation, 1988; Exposure from natural sources of radiation, 1993; Sources, effects and risk of ionizing radiation, 2000). The data can be also used to create the radioactive contour maps of the investigated area.