Radioactive Cesium Isotopes Research Articles

Challenges in development and management of orphan drugs—a case study of Prussian blue insoluble

Prussian blue insoluble (PB) is an antidote for decorporation of radioactive and non-radioactive isotopes of thallium and cesium. Its dosage in the form of capsules, Radiogardase-Cs, is a United States Food and Drug Administration approved formulation since 2003. In India and many other countries, this drug is not available and in case of requirement it is imported from US or Europe. The author has worked extensively to make PB capsules available in India. The drug was recently approved by the Indian drug regulatory agency, Central Drugs Standard Control Organisation and is now available commercially in India. However this drug needs special attention as it is an orphan drug with limited requirement. The post-approval phase of this drug poses a different set of challenges and the author has highlighted some key issues with probable approaches for post-approval product management.

Распределение радиоактивного и стабильного цезия в почвах и растениях лесных экосистем

The paper presents the results of determining the content of radioactive (137Cs) and stable (133Cs) isotopes of cesium in soil and plant samples (lichens, mosses, bark, wood) collected in a medium-aged pine forest on the territory of the Polesye State Radiation-Ecological Reserve, as well as the results of the experiment to assess the vertical precipitation of 137Cs on horizontal plates. The ratios of concentrations of 137Cs to 133Cs have been calculated, which can be used to quantify the level of equilibrium between 137Cs and 133Cs in the forest ecosystems. Based on the assumption that the physicochemical properties of 133Cs and 137Cs are similar, the analysis of 133Cs and comparison of its ratios with 137Cs can be useful for understanding the long-term behavior of the radionuclide and its equilibrium distribution in forest ecosystems. As a result of the conducted research, it was established that the precipitation activity of 137Cs in the composition of tree litter is higher in comparison with the atmospheric precipitation of the radionuclide on horizontal plates. In the autumn season, there is a decrease in the average daily values of 137Cs activity observed in the samples of radioactive fallout from the atmosphere and an increase in the tree litter samples. At the same time, more than half of the total activity of the radionuclide is retained by the tree litter. The vertical distribution of the 137Cs exchange form in the forest soil’s mineral layers was compared to that of 133Cs. The total content of 137Cs in the soil profile decreases with depth. The content of the 137Cs exchange form in the soil profile has an uneven distribution, and the concentration of the stable isotope’s exchange form increases with depth. The 137Cs to 133Cs ratios in the soil profile decrease with a soil depth from the horizon of 0-5 cm to the horizon of 15-20 cm, which indicates a nonequilibrium ratio of these isotopes. It is shown that the content of 137Cs and 133Cs in lichens, mosses, bark and wood varies depending on the type of a sample and the part of a plant. The highest activity values of 137Cs were determined in lichens and mosses. Under conditions of co-growth, mosses are characterized by a higher concentration of 133Cs when compared to lichens. A good correlation was noted between the content of 137Cs and 133Cs for all types of the plant samples. This result suggests the conclusion that these plants absorb 137Cs similarly to 133Cs.

Hierarchical Structures Incorporating Carbon and Zeolite to Remove Radioactive Contamination

Synthesis, characterization and application of hierarchical zeolites are becoming a subject of an increasing interest among scientists and researchers. Hierarchical structures incorporating zeolites possess secondary porosity at meso- and macrolevel to overcome problem of mass transport, which occurs with using conventional zeolites.
 In this study, the porous carbon surface was prepared by carbonization of the locally available agricultural waste of the Iraqi Nut shell (NS) using a carbonization method in a tubular furnace at 900ËšC for two hours. Hierarchicalpours structures including zeolite were prepared by the mechanical activation of the carbon surface using ultrasonication with a nanoparticles suspension of ground commercial zeolite type 4A. Zeolite was milled using 0.3-0.4 mm diameter glass balls as grinding media to prepare nanoparticles seeding, which increases the crystallization of the amorphous aluminosilica gel on the modified carbon surface during the hydrothermal method. The Product of the syntheses of zeolite 4A and the hierarchal composite material were characterized using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Nitrogen-Adsorption /desorption isotherms (BET), Energy Dispersive Spectroscopy (EDX), and Thermo Gravimetric Analysis (TGA) to determine the structure, morphology, surface area, chemical composition, and percentage weight of zeolite on carbon, respectively. The products were applied to remove the radioactive hazardous cesium isotope Cs137 from the radioactive wastewater provided by the destroyed building of Radiochemistry laboratories (RCL) in AL-Tuwaitha Nuclear Site. Gamma spectroscopy system with high purity germanium detector (HPGe) was used to measure the activity concentration for the contamination water before and after the treatment. The results showed that the activity concentration decreased from 4800 Bq/L to 186Bq/L and 100Bq/L using pure zeolite 4A and NSZ.respectively. The results also showed that the composite materials could be used effectively to remove radioactive 137Cs from a real wastewater, with ease of separation and recovery from the solution compared with the pure zeolite 4A.

The Effect of Gamma Irradiation on the Physiochemical Properties of Caesium-Selective Ammonium Phosphomolybdate–Polyacrylonitrile (AMP–PAN) Composites

Managing certain by-products of the nuclear fuel cycle, such as the radioactive isotopes of caesium: 134Cs, 135Cs and 137Cs is challenging due to their environmental mobility and radioactivity. While a great many materials can isolate Cs+ ions from neutral or basic aqueous solutions via ion exchange, few of these, with the exception of ammonium phosphomolybdate (AMP), function effectively in acidic media. The use of AMP, and its porous composite in polyacrylonitrile (PAN) for management of Cs radioisotopes in various nuclear wastes have been known for decades and are well studied, yet the effects of radiation on the physiochemical properties of such composites have only received limited attention to date. In a previous publication, we demonstrated that a 100 kGy gamma irradiation dose has negligible effect on the ion exchange performance of AMP and AMP–PAN with respect to capacity or kinetics under the Cs+ concentrations and acidity found in spent nuclear fuel (SNF) recycling. As a continuation of this prior study, in this publication we explore the effects of gamma irradiation on the physiochemical properties of AMP and AMP–PAN using a range of characterisation methods. The effects of the same gamma dose on the oxidation state of Mo in AMP and AMP–PAN, the thermal degradation of both AMP and AMP–PAN, combined with a first study into the high-temperature degradation AMP, are reported. The implications of irradiation, its possible mechanism, the conditions present in SNF recycling, and for the end-of-life disposal or recycling of these materials are also discussed.

Potential of the submerged plant Myriophyllum spicatum for treatment of aquatic environments contaminated with stable or radioactive cobalt and cesium

Modern technological routes of decontamination of polluted environments are expected to outperform traditional strategies. Such routes have been perceived as more efficient and/or less expensive, and, most of all, as environmentally friendly. In this context, submerged plants without any agricultural use are considered new and intriguing alternatives in the current search for more sustainable remediation of toxic and radioactive wastewater.Myriophyllum spicatum (Eurasian watermilfoil), a submerged aquatic plant present in fresh water streams, is considered a threat for aquatic environment. In present research, this plant was utilized for decontamination of simulated wastewater spiked with both radioactive and non-radioactive cobalt and cesium isotopes. Several parameters were evaluated to optimize the phytoremediation of these elements, such as the pH-value of the contaminated medium, illumination, contact time, ion competition, concentration of dissolved elements, mass of plant, and content of radioactive material. More than 90% and 60% of stable cobalt and cesium, respectively, were eliminated at optimal conditions of contact time with higher pH-value, light, and optimum mass of applied biomass. The same elimination values were achieved also in case of using radioisotopes of the same elements. The study demonstrates that Myriophyllum spicatum can be used as a promising candidate for phytoremediation of cobalt and cesium even if present as radioisotopes from contaminated aqueous media, thus being a green alternative for traditional remediation technologies.

Radioactive and stable cesium isotope distributions and dynamics in Japanese cedar forests

Dynamics of the Fukushima-derived radiocesium and distribution of the natural stable isotope 133Cs in Japanese cedar (Cryptomeria japonica D. Don) forest ecosystems were studied during 2014–2016. For the experimental site in Yamakiya, Fukushima Prefecture, we present the redistribution of radiocesium among ecosystem compartments during the entire observation period, while the results obtained at another two experimental site were used to demonstrate similarity of the main trends in the Japanese forest ecosystems. Our observations at the Yamakiya site revealed significant redistribution of radiocesium between the ecosystem compartments during 2014–2016. During this same period radionuclide inventories in the aboveground tree biomass were relatively stable, however, radiocesium in forest litter decreased from 20 ± 11% of the total deposition in 2014 to 4.6 ± 2.7% in 2016. Radiocesium in the soil profile accumulated in the 5-cm topsoil layers. In 2016, more than 80% of the total radionuclide deposition in the ecosystem resided in the 5-cm topsoil layer.The radiocesium distribution between the aboveground biomass compartments at Yamakiya during 2014–2016 was gradually approaching a quasi-equilibrium distribution with stable cesium. Strong correlations of radioactive and stable cesium isotope concentrations in all compartments of the ecosystem have not been reached yet. However, in some compartments the correlation is already strong. An increase of radiocesium concentrations in young foliage in 2016, compared to 2015, and an increase in 2015–2016 of the 137Cs/133Cs concentration ratio in the biomass compartments with strong correlations indicate an increase in root uptake of radiocesium from the soil profile. Mass balance of the radionuclide inventories, and accounting for radiocesium fluxes in litterfall, throughfall and stemflow, enabled a rough estimate of the annual radiocesium root uptake flux as 2 ± 1% of the total inventory in the ecosystem.

Fission product inventory and burnup evaluation of the AGR-2 irradiation by gamma spectrometry

Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program’s second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide/uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. The measured activities were used to calculate the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15% fission per initial metal atom (FIMA) and 9.01–10.69% FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1% FIMA for UCO compacts and 8.5–10.6% FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

Consensus building for interlaboratory studies, key comparisons, and meta-analysis

Interlaboratory studies in measurement science, including key comparisons, and meta-analyses in several fields, including medicine, serve to intercompare measurement results obtained independently, and typically produce a consensus value for the common measurand that blends the values measured by the participants.Since interlaboratory studies and meta-analyses reveal and quantify differences between measured values, regardless of the underlying causes for such differences, they also provide so-called ‘top–down’ evaluations of measurement uncertainty.Measured values are often substantially over-dispersed by comparison with their individual, stated uncertainties, thus suggesting the existence of yet unrecognized sources of uncertainty (dark uncertainty). We contrast two different approaches to take dark uncertainty into account both in the computation of consensus values and in the evaluation of the associated uncertainty, which have traditionally been preferred by different scientific communities. One inflates the stated uncertainties by a multiplicative factor. The other adds laboratory-specific ‘effects’ to the value of the measurand.After distinguishing what we call recipe-based and model-based approaches to data reductions in interlaboratory studies, we state six guiding principles that should inform such reductions. These principles favor model-based approaches that expose and facilitate the critical assessment of validating assumptions, and give preeminence to substantive criteria to determine which measurement results to include, and which to exclude, as opposed to purely statistical considerations, and also how to weigh them.Following an overview of maximum likelihood methods, three general purpose procedures for data reduction are described in detail, including explanations of how the consensus value and degrees of equivalence are computed, and the associated uncertainty evaluated: the DerSimonian–Laird procedure; a hierarchical Bayesian procedure; and the Linear Pool. These three procedures have been implemented and made widely accessible in a Web-based application (NIST Consensus Builder).We illustrate principles, statistical models, and data reduction procedures in four examples: (i) the measurement of the Newtonian constant of gravitation; (ii) the measurement of the half-lives of radioactive isotopes of caesium and strontium; (iii) the comparison of two alternative treatments for carotid artery stenosis; and (iv) a key comparison where the measurand was the calibration factor of a radio-frequency power sensor.

Selective Removal of Radioactive Cesium from Nuclear Waste by Zeolites: On the Origin of Cesium Selectivity Revealed by Systematic Crystallographic Studies

Selective ion-exchange with zeolites has been considered as one of the most promising means to remove a radioactive isotope of cesium, 137Cs, present in low concentration in seawater. However, there has been no report on the fundamental structure–property relation of zeolite-based Cs ion-exchangers. In this study, we investigate the origin of the selectivity of the radioactive cesium isotope in zeolite frameworks using zeolite A (LTA) as a model system. We prepared seven single crystals of fully dehydrated and partially cesium exchanged Zeolite A (LTA) with different Cs+/Na+ ratios. Their single-crystal synchrotron X-ray diffraction experiments revealed the significant differences in the degree of exchange and the site selectivity of Cs+ ions depending on the initial Cs+ concentrations in given ion exchange solutions. The degree of Cs+-ion exchange increases from 15.8 to 44.2% as the initial Cs+ concentration increases and the Na+ content decreases. In addition, it was found that Cs+ ions are energeticall...

A novel role for methyl cysteinate, a cysteine derivative, in cesium accumulation in Arabidopsis thaliana

Phytoaccumulation is a technique to extract metals from soil utilising ability of plants. Cesium is a valuable metal while radioactive isotopes of cesium can be hazardous. In order to establish a more efficient phytoaccumulation system, small molecules which promote plants to accumulate cesium were investigated. Through chemical library screening, 14 chemicals were isolated as ‘cesium accumulators’ in Arabidopsis thaliana. Of those, methyl cysteinate, a derivative of cysteine, was found to function within the plant to accumulate externally supplemented cesium. Moreover, metabolite profiling demonstrated that cesium treatment increased cysteine levels in Arabidopsis. The cesium accumulation effect was not observed for other cysteine derivatives or amino acids on the cysteine metabolic pathway tested. Our results suggest that methyl cysteinate, potentially metabolised from cysteine, binds with cesium on the surface of the roots or inside plant cells and improve phytoaccumulation.

CLINOPTILOLITE WITH CESIUM IMMOBILIZATION TO POTASSIUM MAGNESIUM PHOSPHATE MATRIX

The possibility of potassium magnesium phosphate (PMP) matrix application for immobilization of clinoptilolite with simulator of radioactive cesium isotopes was investigated. X-ray phase analysis of the natural clinoptilolite sample has shown that it includes two main phases of clinoptilolite (Na,K)4CaAl6Si30O72·24H2O, and mordenite (Na2Ca, K2) 4Al8Si40O96 · 28H2O. In addition, impurities of SiO2, Fe2O3 and TiO2 phases are observed. To saturate clinoptilolite with cesium, 0.5 M solution of cesium chloride was used. A chemical analysis of clinoptilolite after saturation with cesium has demonstrated that the content of cesium in clinoptilolite was about 2 wt.%. After the introduction of clinoptilolite with cesium in the PMP matrix, the obtained material was identified as potassiummagnesium phosphate with the presence of clinoptilolite, mordenite, TiO2 and unreacted MgO phases. The results of the electron microscopy analysis have shown that cesium was dislocated between PMP matrix and clinoptilolite, incorporated into the PMP matrix. Normalized leaching rate of cesium from PMP matrix with 25wt.% clinoptilolite was about 3.2.10-4 g / cm2 per day after 7 days testing.

ICP-MS/MSによる放射性セシウム同位体分析法の開発と土壌試料への応用

ICP-MS/MSによる放射性セシウム同位体分析法の開発と土壌試料への応用

国内農畜水産物の放射性セシウム汚染の年次推移と加工·調理での放射性セシウム動態研究の現状

The Tokyo Electric Power Company (TEPCO) Fukushima Daiichi nuclear power plant accident caused by the Great East Japan Earthquake on March 11, 2011, resulted in the release of large amounts of radioactive materials (mainly radioactive iodine 131I, and radioactive cesium 134Cs and 137Cs) into the environment that subsequently contaminated agricultural products. Currently, agricultural contamination by radioactive iodine, with a short half-life of 8d, is no longer an issue, since three-and-a-half years have passed since the accident. However, the radioactive cesium isotopes 134Cs and 137Cs have long half-lives (2 years and 30 years), and have maintained 30% and 92% of their initial radioactivity, respectively. Therefore, long-term monitoring of these radionuclides is required with respect to food contamination. Consumers and food manufacturers alike are greatly concerned with the behavior of radioactive materials during the food processing and cooking of raw agricultural materials. Under a wide range of countermeasures to mitigate the consequences of the nuclear accident for agriculture in the affected regions of Japan, the contamination of agricultural products with radioactive cesium has been greatly reduced in the past three-and-a-half years. Furthermore, numerous studies have focused on examining the behavior of radioactive cesium during the processing and cooking of domestic agricultural, livestock, and fishery products. In this paper, we provide an overview of the inspection results of FY2011 to FY2013 on radioactive cesium levels in agricultural, livestock, and fishery products, as well as research results collected to date on radioactive cesium behavior in the processing and cooking of these products. An English version of all figures and tables in this paper is presented in the Appendix.

Determination of radioactive cesium isotope ratios by triple quadrupole ICP-MS and its application to rainwater following the Fukushima Daiichi Nuclear Power Plant accident

A method was developed for the determination of 134Cs/137Cs and 135Cs/137Cs in rainwater samples using a triple quadrupole ICP-MS, with the objective of investigating radioactive cesium isotope ratios released by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. The high background caused by Ba ions and Xe impurities in argon plasma gas has made it difficult to carry out determination of the 134Cs/137Cs and 135Cs/137Cs ratios on conventional ICP-MS instruments without prior chemical separation. In this study, nitrous oxide was used as the reaction gas for reducing the isobaric interference by 134Ba, 135Ba, 137Ba and 134Xe, and an additional quadrupole in front of the reaction cell was shown to effectively remove Sn and Sb that could have produced possible interference such as SbO and SnO by the N2O reaction. The detection limit for 134Cs, 135Cs and 137Cs in solution containing Ba was successfully improved. In order to confirm the applicability of this method to the measurement of 134Cs/137Cs and 135Cs/137Cs ratios of rainwater, four samples were collected for analysis from 40–200 km away from the FDNPP. The measured 134Cs/137Cs ratios in the samples are consistent with the values determined by Ge semiconductor analysis to within the analytical error, suggesting that the developed method can provide reliable isotopic data without any correction of the mass-discrimination effect. No variation was found in the 135Cs/137Cs ratios of the four samples, suggesting either the same contamination source or a uniformly consistent mixing ratio between contamination sources. The measured 135Cs/137Cs ratios in the samples are different from global fall-out values and from that of Chernobyl. This result indicates that the value of the rainwater samples can be used as a radiocesium tracer in the environment.

Radioactive cesium isotope ratios as a tool for determining dispersal and re-dispersal mechanisms downwind from the Nevada Nuclear Security Site

Fractionation of the two longer-lived radioactive cesium isotopes (135Cs and 137Cs) produced by above ground nuclear tests have been measured and used to clarify the dispersal mechanisms of cesium deposited in the area between the Nevada Nuclear Security Site and Lake Mead in the southwestern United States. Fractionation of these isotopes is due to the 135-decay chain requiring several days to completely decay to 135Cs, and the 137-decay chain less than one hour decay to 137Cs. Since the Cs precursors are gases, iodine and xenon, the 135Cs plume was deposited farther downwind than the 137Cs plume. Sediment core samples were obtained from the Las Vegas arm of Lake Mead, sub-sampled and analyzed for 135Cs/137Cs ratios by thermal ionization mass spectrometry. The layers proved to have nearly identical highly fractionated isotope ratios. This information is consistent with a model where the cesium was initially deposited onto the land area draining into Lake Mead and the composite from all of the above ground shots subsequently washed onto Lake Mead by high intensity rain and wind storms producing a layering of Cs activity, where each layer is a portion of the composite.

Impacts of the Fukushima Nuclear Power Plants on Marine Radioactivity

The impacts on the ocean of releases of radionuclides from the Fukushima Dai-ichi nuclear power plants remain unclear. However, information has been made public regarding the concentrations of radioactive isotopes of iodine and cesium in ocean water near the discharge point. These data allow us to draw some basic conclusions about the relative levels of radionuclides released which can be compared to prior ocean studies and be used to address dose consequences as discussed by Garnier-Laplace et al. in this journal. The data show peak ocean discharges in early April, one month after the earthquake and a factor of 1000 decrease in the month following. Interestingly, the concentrations through the end of July remain higher than expected implying continued releases from the reactors or other contaminated sources, such as groundwater or coastal sediments. By July, levels of (137)Cs are still more than 10,000 times higher than levels measured in 2010 in the coastal waters off Japan. Although some radionuclides are significantly elevated, dose calculations suggest minimal impact on marine biota or humans due to direct exposure in surrounding ocean waters, though considerations for biological uptake and consumption of seafood are discussed and further study is warranted.

Application of the thermal effect of the atmosphere ionization for remote diagnostics of the radioactive pollution of the atmosphere

1560 We study the interaction processes of the radioac� tive isotopes of cesium�137 ( 137 Cs) and iodine�131 ( 131 I) with the boundary atmospheric layer. Energetic electrons emitted by 137 Cs (electronic energy 170.8 keV) and 131 I (electronic energy 970 keV) and the products of their secondary fission produced by the collision ionization of molecules of atmospheric gases lead to the formation of a large number of initial ions. The ini� tial ions participate in chemical reactions, and simul� taneously, they are subjected to hydration and associa� tion of water vapor molecules. This process is called ion ageing. In the case of a sharp increase of the ion� ization rate as occurs during reactor accidents at atomic power stations, hydration of ions acquires an explosive character (in the literature, this process is

Synthesis and Structural Characterization of K3Th2(PO4)3F2 and RbThPO4F2 as Potential Nuclear Waste Storage Materials

Two new alkali thorium phosphate materials, K3Th2(PO4)3F2 and RbThPO4F2, were isolated by hydrothermal synthesis at 575 °C. These structures were characterized by single crystal X-ray diffraction using a full-matrix least squares method. The K3Th2(PO4)3F2 compound crystallizes in C2/c (No. 15) with a = 15.8179(15) A, b = 9.8172(8) A, c = 9.6472(9) A, β = 121.132(7)°, Z = 4 and R 1 = 0.0329. This structure contains two large open channels possibly suitable for incorporating radioactive cesium isotopes for waste storage. The RbThPO4F2 structure forms in the P2 1 /m (No. 11) space group with a = 6.719(4) A, b = 6.002(3) A, c = 7.431(5) A, β = 113.925(19)°, Z = 2 and R 1 = 0.0359. Unique to this material is a chain of edge sharing thorium with square antiprism coordination environments where fluorine occupies both sites along the edge. Both structures also represent the first occurrences of a fluorinated alkali thorium phosphate material. Two novel fluorinated alkali thorium phosphate structures, K3Th2(PO4)3F2 and RbThPO4F2, were prepared by hydrothermal synthesis as potential radioactive waste storage materials.

Interaction of the Cesium Cation with Mono-, Di-, and Tricarboxylic Acids in the Gas Phase. A Cs+ Affinity Scale for Cesium Carboxylates Ion Pairs

Humic substances (HS), including humic and fulvic acids, play a significant role in the fate of metals in soils. The interaction of metal cations with HS occurs predominantly through the ionized (anionic) acidic functions. In the context of the effect of HS on transport of radioactive cesium isotopes in soils, a study of the interaction between the cesium cation and model carboxylic acids was undertaken. Structure and energetics of the adducts formed between Cs+ and cesium carboxylate salts [Cs+RCOO-] were studied by the kinetic method and density functional theory (DFT). Clusters generated by electrospray ionization mass spectrometry from mixtures of a cesium salt (nitrate, iodide, trifluoroacetate) and carboxylic acids were quantitatively studied by CID. By combining the results of the kinetic method and the energetic data from DFT calculations, a scale of cesium cation affinity, CsCA, was built for 33 cesium carboxylates representing the first scale of cation affinity of molecular salts. The structural effects on the CsCA values are discussed.

Taking into account absorbed doses in tooth enamel due to internal irradiation of human body by radioactive cesium isotopes at analysis EPR dosimetry data: Calculation by Monte-Carlo method

By Monte-Carlo simulation of ionizing particles transport, for a realistic mathematical phantom of a man supplemented by a dental region, absorbed doses in teeth enamel and whole body doses are calculated for cases of internal irradiation by Cs 137 and Cs 134 isotopes incorporated in the human body resulted from staying in radioactive contaminated territory. It is shown that dose in enamel constitutes ( 40 ± 4 ) % and ( 59 ± 6 ) % of whole body dose resulted from the decay of Cs 137 and Cs 134 isotopes, respectively. The results of calculations may be used for conversion of absorbed dose in enamel obtained by the tooth enamel EPR spectroscopy method to whole body dose for dosimetric investigation of population of territories contaminated by the radioactive cesium, which is specific for the Chernobyl accident.