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The decommissioning of a nuclear power plant generates a large amount of radioactive waste that requires significant disposal costs. Consequently, it is an important factor in assessing decommissioning costs. The most effective approach to minimizing decommissioning waste is rapid classification based on radioactivity levels. However, some nuclear sites do not have their own radiochemical analysis laboratory. Even in Korea, the analysis process does not' occur at the decommissioning site but rather at an external analysis institution to ascertain concentrations. This analysis procedure is time‐consuming and may result in cross‐contamination among radioactive wastes. Therefore, rapid analysis of decommissioning waste can reduce the amount of radioactive waste disposal and ultimately improve the economics. To address these issues, research is ongoing to develop a mobile radiochemistry laboratory. This study evaluated the radiological effects on workers as a basis for the application of mobile facilities on‐site. Worker exposure doses were assessed using computational code, considering the analysis workload in single and continuous processes under both normal and abnormal operations. The preliminary evaluation results from this prestudy confirm regulatory dose limits, and it is anticipated that future studies can be augmented with field data. [ABSTRACT FROM AUTHOR]

This study investigates the radiation dose that humans receive from naturally occurring uranium-series radionuclides, with a focus on alpha-emitting polonium-210 (210Po), which has a half-life of 138.4 days. Polonium is efficiently absorbed by living organisms and is estimated to contribute approximately 7% of the total effective dose from ingested natural internal radiation. The primary source of atmospheric 210Po is the decay of radon-222 (222Rn), which precipitates onto land and water surfaces, including crops. In Cannabis sativa, 210Po accumulates primarily through direct deposition on leaf surfaces and from fertilizers, particularly phosphate fertilizers. This study examined 10 samples of dried hemp (Cannabis sativa L.) legally available in Poland, assessing 210Po concentrations through radiochemical analysis. Various consumption methods were analyzed, including smoking with a glass pipe, a water pipe (bong), a cigarette (joint or spliff), and vaporization. The desorption of 210Po during combustion and vaporization was measured, revealing significant differences based on the method used. Results showed that smoking with a glass pipe resulted in the highest desorption of 210Po (approximately 80%), while water pipe and blunt smoking exhibited lower desorption rates (around 40%). The efficiency of 210Po adsorption in filters varied, with water filters showing about 8% absorption and cellulose filters about 20%. Vaporization results indicated that the desorption of 210Po increased with temperature. These findings underscore the importance of considering the method of consumption when calculating the radiation dose from 210Po, as the differences can significantly impact the accuracy of dose assessments. The study highlights the need for further research to optimize safety guidelines for cannabis consumption in relation to radioactive contaminants. [ABSTRACT FROM AUTHOR]

Background/Objectives: PET imaging of bacterial infection could potentially provide added benefits for patient care through non-invasive means. [68Ga]Ga-desferrioxamine B—a radiolabelled siderophore—shows specific uptake by human-pathogenic bacteria like Staphylococcus aureus or Pseudomonas aeruginosa and sufficient serum stability for clinical application. In this report, we present data for automated production of [68Ga]Ga-desferrioxamine B on two different cassette-based synthesis modules (Modular-Lab PharmTracer and GRP 3V) utilising commercially obtainable cassettes together with a licensed 68Ge/68Ga radionuclide generator. Methods: Quality control, including the determination of radiochemical purity, as well as a system suitability test, was set up via RP-HPLC on a C18 column. The two described production processes use an acetic acid/acetate buffer system with ascorbic acid as a radical scavenger for radiolabelling, yielding ready-to-use formulations with sufficient activity yield. Results: Batch data analysis demonstrated radiochemical purity of >95% by RP-HPLC combined with ITLC and excellent stability up to 2 h after synthesis. Specifications for routine production were set up and validated with four masterbatches for each synthesis module. Conclusions: Based on this study, an academic clinical trial for imaging of bacterial infection was initiated. Both described synthesis methods enable automated production of [68Ga]Ga-desferrioxamine B in-house with high reproducibility for clinical application. [ABSTRACT FROM AUTHOR]

On October 31, 1952, the United States successfully detonated the Los Alamos Mike thermonuclear device on the surface of Elugelab Island at Eniwetok Atoll in the Pacific Ocean. This test was the first demonstration of a high-yield thermonuclear explosion on Earth. The 10.4-Mt device yield obliterated Elugelab Island and left a 6240-ft-diameter underwater crater. Later, radiochemical analysis of the explosion debris produced the unanticipated discovery of 15 new heavy transuranic isotopes and two new elements, which were later named einsteinium and fermium. Initially, the discovery of these elements was classified, but in 1955, the results were declassified and announced to the world. The Mike results later led to the development of the Heavy Element and Isotope Effort under the U.S. Plowshare Peaceful Nuclear Explosions Program, under which additional new heavy transuranic isotopes were produced. [ABSTRACT FROM AUTHOR]

Between 2016 and 2021, Germany's first total diet study was performed to assess the variety of substances humans are exposed to by dietary intake. On a global scale rather unique, the natural radionuclides lead-210, uranium-234, uranium-238, radium-226, and radium-228 should be investigated in over 200 different food samples within that study. This paper serves as a guide how to successfully determine these natural radionuclides in very low concentrations in a variety of samples. Two independent laboratories were involved for comparison to assure the quality of the presented sample pretreatment and analyzing techniques. [ABSTRACT FROM AUTHOR]

The subject of this research is the vertical migration of strontium-90 in peatlands of the European Subarctic region of Russia. The activity level of strontium-90 has been determined in peat samples, and the physicochemical parameters of peat deposits have been studied. The specific activity of the radionuclide has been determined using beta radiometric methods with radiochemical preparation according to the methodology. The physicochemical parameters of the peat have been determined using weight-based methods according to the specified procedures. The influence of physicochemical parameters on the vertical migration of the radionuclide in peatlands has been evaluated using correlation analysis. The results have shown that the specific activity of strontium-90 in peat deposits ranges from 0.25 to 7.7 Bq/ kg. The results are consistent with typical values for all soils in Russia. The average value of the specific activity of strontium-90 in peat deposits is estimated to be 1.5±0.02 Bq/kg, which is below the established minimum values and average parameters for all soils in Russia. The pathways of vertical migration of strontium-90 in peat deposits demonstrate a downward direction with various trajectories. These pathways serve as a trace of past global atmospheric radioactive fallout. The vertical migration of strontium-90 in peat is associated with the organic matter content, ash content in peatlands, and recent local atmospheric fallout from nuclear fuel facilities. The research results provide valuable information for predicting the migration of strontium-90 into aquifers under changing environmental conditions due to the Arctic's rapid climate warming. [ABSTRACT FROM AUTHOR]

A purification method is developed to determine 90Sr in radioactive waste. A separation based on Sr-resin® with a pretreatment using TRU-resin® provides satisfactory Sr recovery yields before the 90Sr measurement by liquid scintillation counting (LSC) regardless the analyzed samples with low or high activity level. The selectivity of the procedure is checked by measuring the 90Y ingrowth after different days of separation without waiting for secular equilibrium. In order to obtain a REACH compliant method without scintillation cocktails, a plastic scintillation resin selective for Sr is implemented on the basis of the developed protocol. The optimized method is applied successfully to representative nuclear waste including samples with high Pu content (effluents, concretes and sludges). [ABSTRACT FROM AUTHOR]

A novel method for rapid radioanalytical measurement of uranium and plutonium in 100ml emergency urine samples was developed, through optimized selection of the separation and purification process and a combined measurement with ICP-TOF-MS and alpha spectrometry. The typical analytical time is within 6 h, the recovery rates are more than 80%, and the minimum detection activity concentrations are 3.4 × 10−4 Bq/L for 238U and 2.5 × 10−3 Bq/L for 239Pu respectively. The spiked test shows that this method can be used for quantitative evaluation of the activity concentration of 238U and 239Pu in urine samples accurately. [ABSTRACT FROM AUTHOR]

Groundwater carries radioactive elements like 226Ra, 222Rn, and 210Po during its flow beneath and above the land. When this water is used for drinking, cooking and other household purposes, the radioactive substances in the water may enter the human body and cause adverse health effects. This study was conducted to determine the distribution of 226Ra, 222Rn, and 210Po in the groundwater samples of Chamarajanagar District, Karnataka, India. The activity of 222Rn in 66 places was studied using the smart radon monitor. The activity of 226Ra, and 210Po was studied at 12 places using emanometry technique and radiochemical analysis, respectively. The activity of 222Rn in groundwater samples varied from 0.94 ± 0.13 to 26.90 ± 3.53 Bq L−1 with an average of 4.44 ± 0.56 Bq L−1. The activity of 226Ra, and 210Po varied from 2.18 ± 0.31 to 96.42 ± 16.55 mBq L−1 with an average of 31.38 ± 9.93 mBq L−1 and 0.72 ± 0.24 to 6.33 ± 0.88 mBq L−1 with an average of 2.86 ± 0.52 mBq L−1, respectively. A good correlation between 226Ra, 222Rn, and 210Po was observed, indicating that they might be of the same origin. The average ingestion dose due to 226Ra, 222Rn, and 210Po were 6.41, 11.58, and 2.51 µSv y−1 respectively, which is less than the recommended effective dose of 100 µSv y−1 associated with the intake of radionuclide from drinking water by WHO. [ABSTRACT FROM AUTHOR]

In radiochemical analysis of decommissioning waste, reference materials are not commercially available and consequently intercomparison exercises are needed for method validations. This paper reports the results from an intercomparison exercise focusing on analyses of α-emitter radionuclides in spent ion exchange resin. The exercise and statistical analysis of the submitted results were carried out based on ISO 13528 standard according to which the assigned values were calculated from the participant's results and the performances were assessed using z-scores, which showed excellent performance for all 241Am analyses, good performance for 238Pu analyses, tolerable performance for 239,240Pu analyses, and questionable 243,244Cm analyses. [ABSTRACT FROM AUTHOR]

The optimal conditions for the preconcentration of 90Sr from natural water samples with carbonate-containing zirconium hydroxide of T-3K grade were determined. A method was developed for the determination of 90Sr in natural waters with strontium concentration with T-3K sorbent of a low detection limit: 0.03 Bq/L from 1 L water samples, 0.02 Bq/L from 2 L sample. The method was tested during monitoring of 90Sr in natural reservoirs in the Sverdlovsk oblast and Chelyabinsk oblast and in water samples from monitoring and observation wells in a long-term RW storage facility locations. It was shown that the developed method can be used without constant monitoring of the yield of strontium in the concentrate for natural waters with a calcium concentration of ≤76 mg/L and a total hardness of ≤5.2 mM, but in view of the established elution yield of 91 ± 1 and 81 ± 2% from 1 and 2 L water samples, respectively, which simplifies and speeds up the analysis. With higher hardness of natural waters, the strontium elution yield as a function of calcium concentration or water hardness reported in the article can be used to determine the yield of strontium in the concentrate. [ABSTRACT FROM AUTHOR]

We report on the first experiment dedicated to the study of nuclear reactions on dopants in a cryogenic capsule at the National Ignition Facility (NIF). This was accomplished using bromine doping in the inner layers of the CH ablator of a capsule identical to that used in the NIF shot N140520. The capsule was doped with 3 × 1016 bromine atoms. The doped capsule shot, N170730, resulted in a DT yield that was 2.6 times lower than the undoped equivalent. The Radiochemical Analysis of Gaseous Samples (RAGS) system was used to collect and detect 79Kr atoms resulting from energetic deuteron and proton ion reactions on 79Br. RAGS was also used to detect 13N produced dominantly by knock-on deuteron reactions on the 12C in the ablator. High-energy reaction-in-flight neutrons were detected via the 209Bi(n,4n)206Bi reaction, using bismuth activation foils located 50 cm outside of the target capsule. The robustness of the RAGS signals suggests that the use of nuclear reactions on dopants as diagnostics is quite feasible. [ABSTRACT FROM AUTHOR]

The efficiency of voloxidation of mixed nitride uranium–plutonium spent nuclear fuel (MNUP SNF) for the separation of the fuel composition from the fuel rod cladding and removal of 3H and 14C was estimated. It was shown that the completeness of SNF separation from fuel rod cladding under optimal conditions is at the level of 98–99%. The residual content of tritium in the voloxidized fuel does not exceed 0.2% of its content in the original SNF sample; radiocarbon is removed by 98%. [ABSTRACT FROM AUTHOR]

• Assembly and fabrication of an automated microfluidic separation and analytical platform based on a disposable solid phase extraction microfluidic chip. • Demonstrated uranium matrix removal and trace elemental assay in the microscale for certified uranium ore concentrate reference material. • The automated platform requires <30 µl of sample per analysis, leads to cost reduction and improved safety. Mass spectroscopy and microfluidic technology, when combined, offer significant advantages in radiochemical analysis sample volume and cost reduction. A microfluidic device designed for efficiency has been developed. This device separates uranium from key trace elements by utilising UTEVA® chromatographic resins and nitric acid solutions of different concentrations for adsorption and recovery. The eluates from this microdevice are then diluted and directed to an inductively coupled plasma mass spectrometry system, enabling direct analysis of trace elements and uranium with minimal operator-sample interaction. This efficient approach greatly reduces the volume of sample required for trace elemental analysis in actinide materials, thereby reducing costs and satisfying the As Low As Reasonably Achievable (ALARA) principle. [ABSTRACT FROM AUTHOR]

Interlaboratory comparison exercises for determining the gross alpha and beta activity concentrations in drinking water, organized by the National Institute for Radiological Protection (NIRP), China CDC, have been carried out since 2012. The purpose of this study is to assess the accuracy and precision of gross alpha and beta analyses of low-level radioactivity concentrations. Natural water samples were used for the comparison, and the performance of the participating laboratories was evaluated with respect to the reference values using the Z -score performance indicator. The comparison data from 2012 to 2022 were analyzed, where the percentage of laboratories with acceptable results was 80–92%, and the dispersion of the measurement results across laboratories became smaller over time. The results demonstrate that these exercises can help laboratories to resolve issues in gross α/β analysis and improve the consistency of the measurement results. • The results of inter-laboratory comparison on gross alpha and gross beta in drinking water in past 10 years in China were summarized and analyzed. • The measurement deviation and the main influencing factors on analytical results were analyzed. • It will improve the quality control of the analysis system in radiochemical laboratories and to obtain accurate and valid measurements. [ABSTRACT FROM AUTHOR]

A need for method validation in radiochemical analyses of decommissioning waste is a challenging task due to lack of commercial reference materials. Participation in an intercomparison exercise is one way for a laboratory to assess their performance and validate their analysis results. A three-year project within the Nordic Nuclear Safety Research (NKS) community was initiated in order to carry out intercomparison exercises on difficult to measure (DTM) radionuclides in real decommissioning waste. Both Nordic and Non-Nordic laboratories participated. This paper reports the results from the final year of the project focusing on beta- and gamma emitter (i.e., easy to measure, ETM) analysis in spent ion exchange resin. The assigned values were derived from the participants' results according to ISO 13528 standard and the performances were assessed using z scores. The results showed generally good performances for both DTMs and ETMs. [ABSTRACT FROM AUTHOR]

The aim of this work was to prove the use of radionuclides deposited in sediment core taken from an overgrowing dystrophic lakes surrounded by marsh-peat vegetation to estimate sedimentary conditions. Sediment core samples were taken from the Toporowe Stawy Lakes (Niżni (TSN) and Wyżni (TSW); Tatra Mountains). The sampling was done using a Limnos corer. After the physical sample preparations, gamma measurements were performed. Radiochemical analysis was applied with the aim of determining 210Pb radioactivity by means of 210Po. The mean values for TSN lake are as follows: 137Cs ~ 123 Bq∙kg−1, 40 K ~ 389 Bq∙kg−1, 228Th ~ 55 Bq∙kg−1, 226Ra ~ 86 Bq∙kg−1, 241Am ~ 5 Bq∙kg−1, and 210Pbuns ~ 180 Bq∙kg−1. For TSW lake, the radioactivity levels of 226Ra and 241Am are comparable to the TSN. The mean values of 137Cs, 40 K, and 228Th are almost twice as high as in TSN. The level of 210Pb in uppermost layer of TSN is higher than in TSW. Sediments were dated by use of 210Pb method, and the rate of sedimentation of each layer was also estimated. Basic chemometric tools were used to confirm the way of deposition of radionuclide, find the correlations between variables, and compare analyzed lakes. It was concluded that the presented type of lakes are a valuable source of information and the vertical distribution of radionuclide can be used to interpret the source of material supply and factors that influence the sedimentation process in recent 150–200 years. [ABSTRACT FROM AUTHOR]

Background: Radiopharmaceuticals are considered as regular medicinal products and therefore the same regulations as for non-radioactive medicinal products apply. However, specific aspects should be considered due to the radiochemical properties. Radiopharmaceutical dedicated monographs are developed in the European Pharmacopoeia to address this. Currently, different quality control methods for non-registered radiopharmaceuticals are utilized, often focusing on radio-TLC only, which has its limitations. When the radiochemical yield (RCY) is measured by radio-TLC analysis, degradation products caused by radiolysis are frequently not detected. In contrast, HPLC analysis defines the radiochemical purity (RCP), allowing for detection of peak formation related to radiolysis. During the introduction and optimization phase of therapeutic radiopharmaceuticals, significant percentages of impurities, like radiolysed construct formation, may have consequential impact on patient treatment. Since more hospitals and institutes are offering radiopharmaceutical therapies, such as [177Lu]Lu-PSMA with an in-house production, the demand for adequate quality control is increasing. Here we show the optimization and implementation of a therapeutic radiopharmaceutical, including the comparison of ITLC and HPLC quality control. Results: Downscaled conditions (74 MBq/μg) were in concordance to clinical conditions (18 GBq/250 µg, 5 mL syringe/100 mL flacon); all results were consistent with an > 98% RCY (radio-TLC) and stability of > 95% RCP (HPLC). Radio-TLC did not identify radiolysis peaks, while clear identification was performed by HPLC analysis. Decreasing the RCP with 50%, reduced the cell-binding capacity with 27%. Conclusion: This research underlines the importance of the radiolabeling and optimization including clinical implementation and clarifies the need for cross-validation of the RCY and RCP for quality control measurements. Only HPLC analysis is suitable for identification of radiolysis. Here we have proven that radiolysed [177Lu]Lu-PSMA has less binding affinity and thus likely will influence treatment efficacy. HPLC analysis is therefore essential to include in at least the validation phase of radiopharmaceutical implementation to ensure clinical treatment quality. [ABSTRACT FROM AUTHOR]

The methods and procedures of dissolution employed in the conduct of radiochemical and elemental analyzes of spent nuclear fuel (SNF) were overviewed, as well as schemes of SNF dissolution, factors influencing the rate and completeness of its dissolution. The methodological techniques were described to separate and study the undissolved residue and localize the volatile components of SNF for their quantitative analysis. [ABSTRACT FROM AUTHOR]

Biodosimetry can define risks in inhabitants of areas with potential contaminants, ensuring environmental protection and living conditions due to toxic and radioactive effects. This study aimed to evaluate metals and radionuclides in dental structures and alveolar bones in residents of a uranium area in Paraíba and Pernambuco, Brazil. Eighty-nine specimens were pulverized, fractionated, and chemically prepared for analysis by EDXRF, FAAS, and ICP-MS. Levels of Ca, Cu, Fe, Si, Mn, Ni, Pb, Sr, Ti, V, Zn, K, Mn, Th, and U were investigated. Higher concentrations were measured for Ca, with an average of 272,986.4 mg kg−1. Ni presented in lower concentrations, with an average of 30.4 mg kg−1. For U, concentrations ranged from 1.5 to 145.0 mg kg−1, with more than 27% of the samples above the reference value of 8.1 μg kg−1. For Th, almost 38% of the results were above the limit of 3.5 μg kg−1. In the bone spicules, the contents of U and Th ranged from 45.1 to 1451.2 μg kg−1 and from 7.5 to 78.4 μg kg−1, in this order. The levels of radionuclides were more expressive for the teeth collected in São José do Sabugi, suggesting contamination through food and water consumption. In the bone spicules, the levels of U were up to 179 times higher than the safety limit. The results indicate a possible risk of contamination with probable induced radiobiological effects. • Elevated Ca levels suggest environmental exposure in uranium regions. • High U concentrations in São José do Sabugi teeth imply local contamination. • Radionuclide levels in bone spicules exceed safety limits, posing health risks. • Urgent measures are needed to mitigate potential radiobiological effects. • Urgent cytogenetic evaluation is needed for genotoxic effects. [ABSTRACT FROM AUTHOR]

We report the first measurement of the 10 B (α , n) 13 N reaction in a polar-direct-drive exploding pusher (PDXP) at the National Ignition Facility (NIF). This work is motivated by the need to develop alternative mix diagnostics, radiochemistry being the focus here. The target is composed of a 65/35 at. % deuterium–tritium (DT) fill surrounded by a roughly 30 μ m thick beryllium ablator. The inner portion of the beryllium ablator is doped with 10 at. % of 10B. Radiation-hydrodynamics calculations were performed in 1D to optimize both the remaining boron rho-R and the DT neutron yield. A charged-particle transport post-processor has been developed to study α-induced reactions on the ablator material. Results indicate a large 13N production from α-induced reactions on 10B, measurable by the radiochemical analysis of a gaseous samples system at the NIF. The PDXP target N201115-001 was successfully fielded on the NIF, and nitrogen from the 10 B (α , n) 13 N reaction was measured. The 13N production yield, as well as the DT neutron yield, was, however, lower than expected. Some of the reduced yields can be explained by the oblate shape, but the ratios of the various radiochemical signals are not commensurate with expectations based on a simple reduction of the 1D results. Preliminary 2D radiation-hydrodynamics computations are consistent with the experimental measurements, and work is ongoing to extend the radiochemistry analysis into higher dimensions. [ABSTRACT FROM AUTHOR]

The purpose of this study was a detailed analysis of all aspects related to the impact of objects and structures of the planned economic activity on the environment on the territory of the Semizbay deposit in the Republic of Kazakhstan. In the course of the work, the geoecological characteristics of the Semizbay deposit were presented. The analysis of data on the state of the components of the natural environment, based on the materials of earlier studies at the facility, was carried out. On the basis of the actual material, a list of priority pollutants subject to monitoring was compiled. The methodology and organization of the projected works are given. The types, conditions, scope of work were indicated. During the study, the following were carried out: soil sampling was carried out in the vicinity of the deposit, radiochemical analysis, and X-ray diffraction analysis. As a result of the study, a program of geoecological research was developed on the territory of the deposit: the content of radionuclides and the mineralogical composition of the sample were determined, which can become an alternative for further research on the territory of the enterprise. [ABSTRACT FROM AUTHOR]

An article contents the review of the data on the content of polonium and lead content: 210Po, 210Pb in natural entities, obtained from literary sources. The review is given of the existing methods for 210Po and 210Pb content investigation in different entities as well as the analysis of the expedience of the applying of the given polonium and lead content investigation in the foodstuffs technique for the use in a method under development of the radiochemical laboratory of the Institute. More perfect and simple for realization than existing method is given for 210Po and 210Pb content investigation in the foodstuffs from a sample with not more than 1.0 kg weight with minimal detectable activity not more than 0.01 Bq. The results are given of the investigation of 210Po and 210Pb content in the certain types of the foodstuffs sampled in the kitchen gardens located in Leningrad region and bought in the trade network of Saint-Petersburg. Estimation of potential average annual population internal exposure dose (Eint) is carried out due to 210Po and 210Pb content in the investigated foodstuffs which are consumed by the local population. For the estimation of the internal exposure doses we used the data on the food rations of adult population of the settlement of the city type according to the data of Rosstat and Internet-resources. It is demonstrated that population internal exposure dose even from several natural radionuclides taking into account consumption of a limited set of foodstuffs could exceed the exposure dose from artificial radionuclide in tens times even for the territories radioactively contaminated after the Chernobyl NPP accident.

Radioactive gas of Unit 1 of the Fukushima Daiichi Nuclear Power Station was released from the exhaust stack shared by Units 1 and 2 through the venting line on March 12th, 2011. In the present study, radiochemical analysis of drain water sampled at the drain pit of the exhaust stack was conducted to study radionuclides released during venting of the Unit 1. Not only volatile 129I, 134Cs and 137Cs but also 60Co, 90Sr, 125Sb and Unit 1-originated stable Mo isotopes were detected. Although Unit 1-originated stable Mo isotopes were clearly detected, their amounts were quite low compared to Cs, suggesting that the formation of Cs2MoO4 was suppressed under the accident condition. Approximately 90% of iodine existed as I− and 10% as IO3− in November 2020. Furthermore, larger amount of 129I than 137Cs was observed, suggesting major chemical form of 131I was molecular iodine rather than CsI at the accident time. The 134Cs/137Cs radioactivity ratio decay-corrected to March 11th, 2011 was 0.86, supported the results that Unit 1 originated radiocesium in environment has smaller 134Cs/137Cs radioactivity ratio than Unit 2 and 3 originated radiocesium. [ABSTRACT FROM AUTHOR]

Development of 3H, 14C, 41Ca, 55Fe and 63Ni radiochemical analysis methods were carried out independently by two laboratories using both inactivate and activated concrete samples. Two preliminary radioanalytical procedures for the non-volatile radionuclides (41Ca, 55Fe, 63Ni) and one Thermal oxidation method for the volatile radionuclides (3H, 14C) were developed. The difficulties in the method development and analysis of results are discussed. [ABSTRACT FROM AUTHOR]

Purpose: Radiation dose estimates in epidemiology typically rely on intake predictions based on urine bioassay measurements. The purpose of this article is to compare the conventional dosimetric estimates for radiation epidemiology with the estimates based on additional post-mortem tissue radiochemical analysis results. Methods: The comparison was performed on a unique group of 11 former Manhattan Project nuclear workers, who worked with plutonium in the 1940s, and voluntarily donated their bodies to the United States Transuranium and Uranium Registries. Results: Post-mortem organ activities were predicted using different sets of urine data and compared to measured activities. Use of urinalysis data collected during the exposure periods overestimated the systemic (liver+skeleton) deposition of 239Pu by 155±134%, while the average bias from using post-exposure urinalyses was –4±50%. Committed effective doses estimated using early urine data differed from the best estimate by, on average, 196±193%; inclusion of follow-up urine measurements in analyses decreased the mean bias to 0.6±36.3%. Cumulative absorbed doses for the liver, red marrow, bone surface, and brain were calculated for the actual commitment period. Conclusion: On average, post-exposure urine bioassay results were in good agreement with post-mortem tissue analyses and were more reliable than results of urine bioassays collected during the exposure. [ABSTRACT FROM AUTHOR]

• Zeolite effectively absorbs Cs-137 and Cs-134 isotopes from U 3 Si 2 /Al fuel solution in the cation–anion exchange method. • In radiochemical analysismethod, using Cs-137 or U-235 as indicator does not yield notable differences in the burnup value. • The highest measured burnup was obtained in the middle position of the fuel plate. • Large uncertainty in the gamma scanning method yields a notable burnup value differences compared to radiochemical analysis techniques. Burnup determination of the U 3 Si 2 -Al fuel plate (FP) with a density of 4.8 gU/cc has been carried out using the destructive method with the isotopes Cs-137 and U-235 as indicators. The FPs were irradiated in the G.A. Siwabessy multi-purpose reactor (RSG-GAS). Burnup determination begins by cutting the U 3 Si 2 -Al FP in a duplicate manner on three positions, top, middle, and bottom, then dissolving it with HCl and HNO 3 to obtain a fuel solution containing fission products of Cs-134, Cs-137, U-235 and other isotopes. The separation of Cs-137 from U-235 was carried out by the cation–anion exchange method using Lampung zeolite with the entire process carried out in a hot cell. The product resulting from the separation was the isotope Cs-137 in the solid phase, while U-235 was in the liquid phase. The amount of Cs-137 and U-235 isotopes were measured with an alpha- and gamma-spectrometry, so the weight of Cs-137 and U-235 can be used to determine the burnup of each FP. The results of burnup calculation of the 4.8 gU/cc U 3 Si 2 -Al FP using the destructive method were 25.06%, 57.96%, and 35.20% on the top, middle, and bottom respectively. There is no significant difference between nominal burnup derived from the weight of the isotopes Cs-137 and U-235 obtained with the destructive method, with the most significant difference to the non-destructive method being 10.26% when using the Cs-137. [ABSTRACT FROM AUTHOR]

Niobium (Nb) is a critical metal usually hosted in pyrochlore and mined from carbonatite deposits. The aluminothermic reduction of pyrochlore concentrate yields ferroniobium (FeNb) alloy and a slag waste. This study presents results from mineralogical, geochemical, and radiochemical investigations of FeNb slag found at the former Saint Lawrence Columbium mine in Oka, Québec, Canada. Slag casts exhibit a vertical zonation resulting from fractional crystallization and differentiation in the melt. Sampling of the slag was designed to characterize resulting chemical and mineralogical variations within casts. The median bulk composition of samples (n = 14) is dominated by Al 2 O 3 (47%) and CaO (16%) from process reagents. The slag also contains significant TiO 2 (4%) and trace elements including Zr (6763 ppm), U (601 ppm), and Th (1371 ppm) from pyrochlore that partition preferentially from concentrate to the slag. Based on radiochemical analyses of daughter products and assuming secular equilibrium, median (n = 3) activity concentrations for U and Th decay series are 213 and 111 Bq/g, respectively. A field spectral radiometric survey of the slag disposal area found median (n = 37) equivalent U and Th concentrations of 1069 and 2101 ppm, respectively. The primary mineralogy of the top and middle of slag casts is dominated by hibonite, grossite, and perovskite. Most of the U and Th is hosted by perovskite. The bottom of slag casts is an assemblage of mainly gehlenite, ferri-gehlenite, hercynite, grossite, and anorthite. The casts also contain a (Na,F,Ce) calcium-aluminate glass decreasing in abundance from top to bottom, and a (Na,F,Ce,Ti,Zr) calcium-aluminosilicate glass in the cast bottoms. The (Na,F,Ce) calcium-aluminate glass, grossite, and hibonite are the phases most susceptible to weathering. Perovskite, gehlenite, and hercynite show little or no signs of alteration. A leach test was performed on three columns filled with material from the top, middle, and bottom of casts. In the field, a parallel leach experiment was conducted with three barrels filled with undifferentiated slag material and open to atmospheric conditions. Column leachate was found to be highly alkaline, with pH in the top column reaching 13.2. Median pH values in column and barrel leachate were 10.4 and 9.2, respectively. The maximum U concentration in column leachate was 13 μg/L whereas in barrel leachate it was 65 μg/L. Maximum Th concentrations in column and barrel leachates were 7.65 and 0.2 μg/L, respectively. Median Al concentrations in column and barrel leachates were 74.9 and 3.9 mg/L, respectively. Slag from the production of FeNb is readily weathered and represents a technologically enhanced naturally occurring radioactive material (TENORM) requiring environmental management because of its radioactivity and the alkaline nature of its leachate. • Conversion of pyrochlore concentrate to ferroniobium alloy produces radioactive slag. • Trace elements in pyrochlore (U, Th, REE, Zr) partition preferentially to the slag. • pH in leachate can reach 13.2 and 9.4 in laboratory and field tests, respectively. • Al in leachate can reach 3025 and 8 mg/L in laboratory and field tests, respectively. • U in leachate can reach 13 and 65 μg/L in laboratory and field tests, respectively. [ABSTRACT FROM AUTHOR]

This paper reports the results obtained in a Nordic Nuclear Safety Research project during the second intercomparison exercise for the determination of difficult to measure radionuclides in decommissioning waste. Eight laboratories participated by carrying out radiochemical analysis of 3H, 14C, 36Cl, 41Ca, 55Fe and 63Ni in an activated concrete. In addition, gamma emitters, namely 152Eu and 60Co, were analysed. The assigned values were derived from the submitted results according to ISO 13,528 standard and the performance assessments were determined using z scores. The measured results were compared with activation calculation result showing varying degree of comparability. [ABSTRACT FROM AUTHOR]

The basis for the release of [18F]FDG for use is the results of quality control studies within the scope of the specification, based on the recommendations of the Pharmacopoeia (FP XI and Ph. Eur. IX). The object of this study is the influence of the [18F]FDG hydrolysis time on the quality parameters, with particular regard to radiochemical purity. The synthesis was performed at three different hydrolysis times: 8, 10, and 12 minutes. 21 syntheses were performed for each time. For the [18F]FDG solution, the radiochemical purity was assessed with the TLC method, the radiochemical and chemical purity with the HPLC method, and the pH value with the potentiometric method. Extending the hydrolysis time significantly increased the radiochemical purity of the final [18F]FDG product, improving its quality parameters (mainly reducing the amount of acetyl derivatives of [18F]FDG while maintaining chemical purity and pH value but with a slight loss of activity. A result at the accept/reject limit may negatively affect the stability test. Increasing the radiochemical purity allows us to avoid the invalidation of this test due to the influence of device measurement error and possible operator error (human). Minimizing contamination reduces impact GLUT independent tumor cell accumulation of [18F]FDG, which its detail of character is still unknown. The possibility of a false-positive result in an imaging examination and minimizes the impact of radiation from contaminants on the patient's tissues. Additional biological studies should be performed to investigate the metabolism of the acetyl derivative of [18F]FDG. [ABSTRACT FROM AUTHOR]

In recent years, naturally occurring radioactive materials (NORM) have become an important topic from the perspective of environmental protection. The list of isotopes that should be monitored in the environment is constantly growing as new amendments to international legislation are introduced. One of the often studied NORM elements is 210Po. In this study, a process of elaborating of a new method of 210Po determination in soil was presented. In the proposed method, several analytical aspects, like the influence of silica decomposition or optimization of an electrode material, were revised. The obtained procedure allows performance of complete radiochemical analysis in a single day, with the chemical efficiency of over 85% and great reduction of costs. Further, the influence of the use of phosphate fertilizers on polonium concentration in soil was also confirmed. [ABSTRACT FROM AUTHOR]

The purpose of this study was to label a trihydroxyflavone with the name of cirsiliol (3',4',5-Trihydroxy-6,7-dimethoxyflavone) with Re/[99mTc]Tc. After that in vivo study in C57 mice with Xenograft melanoma tumor was done. Labeling was optimized, and radiochemical analysis was performed. The high radiochemical yield (> 97%) was achieved for cirsiliol which was stable up to 4 h. Rhenium-labeled cirsiliol characterized the complex formation. High tumor uptake was seen for [99mTc]Tc-cirsiliol (2.16 ± 0.23% ID/g) at 1 h post injection. Because of its ability to accumulate and identify tumors, [99mTc]Tc-cirsiliol has a potential to be considered as new radiotracer for melanoma tumor detecting. [ABSTRACT FROM AUTHOR]