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238U and 234U concentrations, 238U/234U ratios and Na, Ca, Mg, K, Al, As, Cd concentrations were measured in selected surface waters (streams, rivers and lakes), ground waters (dug wells) and underground waters (drill wells and thermal waters) in Quang Nam and Da Nang provinces, Central Vietnam. The mineralization was < 500 mg L−1 and Al, As, Cd contents were a few tenths of µg L−1. 234U and 238U activities were between 0.47–27.6 mBq L−1 and 0.6–15.0 mBq L−1 respectively, these values are lower than WHO recommended limits. Uranium contents trended as Urivers < Ustreams < Ulakes < Udig wells < Uthermal water < Udrill wells. The 234U/238U ratio ranged from 0.69 to 2.31 with 1.26 on average. For groundwaters, the ratio scattered around one. Effects of Nong Son uranium deposit located in Quang Nam region were not observed. [ABSTRACT FROM AUTHOR]

The activity concentrations of 238U, 232Th, and 40K were determined at 56 sites along the East Coast of India, near the Bay of Bengal, with 31 sites in Odisha and 25 in Andhra Pradesh. In Odisha, average concentrations were 109 ± 13 Bq kg−1 for 238U, 296 ± 27 Bq kg−1 for 232Th, and 450 ± 33 Bq kg−1 for 40K, while in Andhra Pradesh, they were 51 ± 13 Bq kg−1, 149 ± 16 Bq kg−1, and 236 ± 21 Bq kg−1, respectively. Absorbed dose rates and annual effective doses were higher outdoors and indoors in Odisha compared to Andhra Pradesh. The calculated radiological parameters exhibited elevated values at certain sampling locations; however, overall, the values generally complied with regulatory standards. [ABSTRACT FROM AUTHOR]

The natural radionuclides in ancient El-Qasr village located in the El-Dakhla oasis (EDO), Egypt's Western Desert were measured using gamma-ray spectrometry equipped with a NaI (Tl) detector. The findings indicate that the samples' mean activity concentrations were 18.61 ± 1.02, 16.67 ± 0.9, and 137.67 ± 6.9 Bq kg−1 for 226Ra, 232Th, and 40K, respectively. The values of Raeq, D, AED, Hex, Hin, Iγ, and ELCR for the samples ranged anywhere from 34.1 to 83.9 Bq kg−1, 15.7 to 37 nGy h−1, 19.26 to 45.384 Sv y−1, 0.09 to 0.23, 0.12 to 0.23, 0.25 to 0.59, and 6.74E−05 to 1.59E−04, respectively. These values are significantly lower than the international limit of 370 Bq kg−1 for Raeq, 59 nGy h−1 for D, 70 Sv y−1 for AED, 1 for Hex and Hin, 2 for Iγ, and 29E−03 for ELCR. According to the obtained data, none of the samples seemed to be a significant risk when it came to radiation exposure. Using these data, we will determine the baseline level of radionuclides that occur naturally in the area that is the subject of the inquiry. [ABSTRACT FROM AUTHOR]

Neutron activated concrete reference material for measurement of residual radioactivity by gamma-ray spectrometry has been prepared. The main radionuclides were 60Co, 152Eu, 54Mn, 154Eu and 134Cs. One-way ANOVA homogeneity test has shown that the samples are homogeneous. The activity concentrations of 54Mn, 59Fe, 154Eu and 134Cs were relatively low; only 60Co activity concentration was found to be higher therefor it was considered as the main target isotope. The prepared sample can be used as a tool to prove compliance to radiation protection and environmental regulations during decommissioning of cyclotron buildings or other irradiation facilities that produce residual radioactivity. [ABSTRACT FROM AUTHOR]

This study evaluates the levels of natural radioactivity in sediment and water samples from Lake Victoria in Jinja, Uganda, with a focus on the radionuclides potassium-40 (40 K), radium-226 (226Ra), and thorium-232 (232Th). We investigated four distinct zones around the lake: fishing (Zone A), farming (Zone B), domestic/livestock (Zone C), and a control zone (Zone D). A total of 15 sediment samples and 15 water samples were collected and analyzed. Sediment samples were obtained using a gravity corer, with a maximum penetration depth of 50 cm. 40 K ranged from 170.479 to 524.883 Bqkg−1 across all zones, 226Ra ranges from 1.51 to 56.78 Bqkg−1 across all zones, and 232Th ranges from 18.18 to 73.10 Bqkg−1 across all zones. 40 K concentrations were highest in the farming zone, likely due to the use of nitrogen, phosphorus, and potassium (NPK) fertilizers. 226Ra and 232Th levels were also elevated in the farming zone, suggesting potential contributions from phosphate fertilizers. Absorbed dose rates varied across the zones, ranging from 28.33 to 58.17 nGyh-1. The measured absorbed dose rates across all zones were within the global average of 59 nGyh−1. The effective annual dose rate ranged from 0.35 to 0.91 mSvy−1 across all zones. Effective annual dose rates did not exceed the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) recommended limit of 1 mSv y−1, indicating low risks to public health from sediment radioactivity. The external index was below the safety threshold, suggesting minimal health risks. In water samples, gross alpha and beta activity concentrations were analyzed. Zone B had the highest average alpha activity concentration (0.64 BqL−1) and beta activity concentration (0.72 BqL−1), while Zone A had the lowest for both alpha (0.16 BqL−1) and beta (0.25 BqL−1) activity concentrations. Gross beta activity was generally higher than gross alpha activity, reflecting potential anthropogenic influences. Most water samples were within the UNSCEAR recommended limits for drinking water quality, except in areas affected by agricultural runoff. This study demonstrates that while the sediments of Lake Victoria in Jinja, Uganda, exhibit varying levels of naturally occurring radionuclides influenced by farming practices, the overall radiation exposure remains within safe limits. Continuous monitoring and regulatory measures are essential to maintain these safety levels and mitigate potential risks from increasing agricultural activities. [ABSTRACT FROM AUTHOR]

The development of the nuclear industry in the countries of the Arabian Gulf demands an investigation of its potential impact on the environment and human activities. It should involve routine monitoring of radionuclide from existing nuclear facilities as well as modelling of accidental release of radioactivity. Agriculture is usually considered the human activity which is the most endangered with radioactive pollution. Although the traditional concept of low-developed agriculture in the United Arab Emirates has been already described from a radioecological point of view, herein, the recent trends of agriculture are recorded. Due to climatic changes and population increase, the use of saline lands will be more pressing. Apart from it, the risk assessment for nuclear events, which was formed mainly for temperate zones, neglected another aspect of arid zones which is underground water reservoirs refilled with episodic heavy rains. The sandy or saline soils are not an effective barrier for the migration of radionuclide deposited in topsoil. A hypersaline environment could prevent the adsorption of radionuclide on soil particles and allow their high bioavailability for halophyte plants. The new principal challenges in radioecological research in arid zones are impacts on (i) saline agriculture, (ii) underground water reservoirs, and (iii) proposal for countermeasures in order to minimise the impact of radioactive contamination. [ABSTRACT FROM AUTHOR]

Naturally occurring radionuclides rocks are one of the possible sources of indoor and outdoor radiation. Samples were taken from Kolar taluk in Karnataka in order to evaluate the radioactive hazards and natural radioactivity levels in those samples. The activity concentrations of 226Ra, 232Th, and 40K in these samples were determined using NaI(Tl) gamma ray spectroscopy. The measured ranged from 5.05 to 171.43 (Bq kg-1); 5.04 to 274.64 (Bq kg-1); 287.23 to 2603.45 (Bq kg-1) for 226Ra, 232Th, and 40K. In this study, the yearly effective radiation dosage, air absorbed gamma radiation dose rate, and hazard index (Hin, Hex), gamma index, activity utilization index, annual gonald dose equivalent were estimated. The study's demonstrate that potassium (40K), a naturally occurring radionuclide, is higher than radium and thorium. The levels of the computed radionuclides were compared to other places in Karnataka and world average value. The relationship between radionuclides was examined using correlation and statistical methods, radiation parameters were also computed. Information on background radioactivity levels and the impacts of radiation on locals in the research area under inquiry is what this study aims to deliver. [ABSTRACT FROM AUTHOR]

Determinations of radioactivity and stable element contents in outlet waters taken from dams (Çamlıdere, Kurtboğazı, Kesikköprü, Çubuk-2) and drinking waters from water treatment plants (İvedik, Pursaklar and Çubuk) of Ankara Water and Sewerage Administration (ASKİ) were performed by using MPC-9604 multi-detector alpha/beta (α/β) counting system, inductively coupled plasma–mass–mass spectrometer and graphite furnace atomic absorption spectrometer. Gross alpha and beta activity levels and element concentrations found in samples were compared with maximum permissible values given by World Health Organization, United State Environmental Protection Agency, Turkish Standards and Türkiye Regulation on Water for Human Consumption. [ABSTRACT FROM AUTHOR]

To analyze groundwater contamination with uranium, groundwater samples were collected from the major industrial area of Jalandhar, Punjab, India (as the industrial effluent is found to contain a large number of heavy metals) and analyzed using ICPMS (Inductively Coupled Plasma Mass Spectrometer) for uranium-238. Uranium-238 concentrations in groundwater ranged from 4.96 µg/L and 38.52 µg/L, with an average of 17.0 µg/L. All the values of uranium concentration and uranium activity concentration in the samples were found within the permissible range by the World Health Organization (WHO). The hazard quotient for all the samples is found to be below one, indicating very low or no risk to the population. [ABSTRACT FROM AUTHOR]

The tritium content in the surface water of the Suifen River in China was measured using an ultra low-level liquid scintillation spectrometer. In August and October, a total of 30 samples were collected (15 per month) The measured 3H activity concentration ranged from 5.08 to 9.75 Bq L−1, and the annual effective dose ranged from 0.07 to 0.13 μSv. These values are below WHO's recommendations, indicating no risk to human health. Although the 3H activity concentration was higher in October than in August, statistical analysis did not show a significant difference between the two months. [ABSTRACT FROM AUTHOR]

Cobalt-60 is usually used for calibration standard that nowadays, it hard to fabricated. This research aims to fabricate of Sealed Source 46Sc as alternative Calibration Standard. Sealed source 46Sc radioactivity was 1.17 ± 0.08 µCi, sealed with an aluminum label. Radiation exposure on the surface opened container is 19.27 ± 0.09 µSv/h, a closed is 10.78 ± 0.15 µSv/h and the distance of 1 m from an open container is 4.40 ± 0.04 µSv/h whereas closed has 2.40 ± 0.04 µSv/h. Multi-channel analyzer γ-spectrometry showed the 46Sc gamma spectrum similar with characteristics from standard 60Co source. [ABSTRACT FROM AUTHOR]

On October 22, 1934, in a fateful experiment, Enrico Fermi and his associates at the University of Rome discovered that neutrons in hydrogen-rich media slow down and acquire enhanced capability for nuclear reactions. The utilization of this phenomenon had far-reaching implications in science and world events. [ABSTRACT FROM AUTHOR]

Background and Objective: Tinengotinib, a novel multi-target small molecule kinase inhibitor, is currently undergoing phase II clinical trial in the USA and China. The purpose of this open-label study was to investigate the absorption, metabolism, and excretion of [14C]tinengotinib following a single oral dose in healthy subjects. Methods: Six healthy male subjects received a single oral dose of [14C]tinengotinib capsules at 10 mg/100 µCi, and blood, urine, and feces samples were collected. Phenotyping experiments were further conducted to confirm the enzymes involved in its metabolism. Results: Tinengotinib was rapidly absorbed in plasma with a time to peak drug concentration (Tmax) of 1.0–4.0 h post-dose and a long terminal half-life (t½) of 23.7 h. Blood-to-plasma radioactivity concentration ratios across timepoints ranged from 0.780 to 0.827, which indicated minimal association of radioactivity with blood cells. The mean cumulative excreted radioactivity was 99.57% of the dose, including 92.46% (68.65% as unchanged) in feces and 7.11% (0.28% as unchanged) in urine. In addition to unchanged tinengotinib, a total of 11 radioactive metabolites were identified in plasma, urine, and feces. The most abundant circulating radioactivity was the parent drug in plasma, which comprised 88.23% of the total radioactivity area under the concentration–time curve (AUC). Metabolite M410-3 was a major circulating metabolite, accounting for 5.38% of the parent drug exposure and 4.75% of the total drug-related exposure, respectively. All excreted metabolites accounted for less than 5.10% and 1.82% of the dose in feces and urine, respectively. In addition, no unique metabolites were observed in humans. Tinengotinib was metabolized mainly via CYP3A4. Conclusions: Overall, tinengotinib demonstrated a complete mass balance with limited renal excretion, no disproportionate blood metabolism, and slow elimination, primarily through the fecal route. The results of this study provide evidence to support the rational use of tinengotinib as a pharmacotherapeutic agent. Registration: ChinadrugTrials.org.cn identifier: CTR20212852. [ABSTRACT FROM AUTHOR]

The occurrence of sand and dust storms (SDS) in Iran has raised many concerns about the possibility of environmental and public health hazards caused by dust particles and pollutants existed in these particles. Therefore, the purpose of this study was to investigate the possibility of contamination of surface soil, river sediments, and roadside deposits with radioactive materials, especially depleted uranium (DU) in the areas affected by SDS. The radioactive activity of the samples was measured by gamma spectroscopy with a high-purity germanium detector. The average activity concentrations of 226Ra, 232Th, and 40 K were 11.19, 8.05, and 76.05 Bq/kg. The average ratio of 238U/235U was 89 indicating the possibility of the presence of DU in the soil samples. The average values of Rm (the share of 235U in total uranium) and DUm were 0.55% (lower than natural uranium, 0.72) and 33% (indicating the presence of 33% DU on average in the samples). Based on 238U/226Ra activity, two samples (S11 and S12) should be considered as DU-contaminated. Almost the obtained results for all radiological risk indices showed lower values than the world average and the possibility of creating a low risk for working people, residents, visitors, and travelers passing through these areas. [ABSTRACT FROM AUTHOR]

In this study, we developed a high efficiency sample pretreatment technique using microwave-assisted acid digestion (MAD) under a mixture of HNO3-HCl-HF-H2O2 conditions, capable of leaching various radioactive nuclides from contaminated soil within 2 h. Our validation results using SRM 2709a soil standard material confirmed that when the MAD process was performed and then repeated, the chemical recovery rates of all 9 elements were consistently above 90%, demonstrating an outstanding leaching efficiency compared to conventional acid leaching (AL) methods. The activity of radionuclides obtained through AL were found to be underestimated compared to those obtained through MAD. We anticipate that the application of this technique for precise activity of radionuclides will contribute to cost savings in decommissioning waste management. [ABSTRACT FROM AUTHOR]

The widespread and excessive occurrence of uranium causes serious environmental risks. This review presents several important analytical methods for determining elemental and isotopic levels of uranium in samples, involving inductively coupled plasma mass spectrometry (ICP-MS), Raman spectroscopy, LED fluorimetry, multi-collector ICP-MS (MC-ICP-MS) and high-resolution ICP-MS (HR-ICP-MS). Furthermore, the methods and application of microbial remediation and phytoremediation in uranium contaminated soil are summarised in this review. A comprehensive discussion is also provided on several mitigation techniques that effectively used to remove uranium from water. These remediation techniques include a variety of biochars, nanotechnology and removal using magnesium-iron based hydrotalcite- like complexes. [ABSTRACT FROM AUTHOR]

This study investigated the radioactivity of groundwater and bottom silt from wells in southern Sinai, Egypt. Eight well sites were chosen (Abu Redis, Abu Zenima, and Al-Tor) and composite samples of water and silt were created from each. Southern Sinai well water (Egypt) was safe for drinking based on tested elements (226Ra < 300 Bq/L, 232Th < 100 Bq/L). However, some bottom silt samples showed elevated 226Ra, 232Th, and 222Rn-, potentially posing health risks through inhalation or ingestion. Further investigation is needed on these specific silt samples due to potential internal and external radiation exposure. [ABSTRACT FROM AUTHOR]

We present the development of a dual-detector system designed for investigating the spectral shape of forbidden non-unique beta decays. Two PbMoO 4 scintillating crystals were carefully prepared for heat and light detection at milli-Kelvin (mK) temperatures. Notably, one crystal was synthesized using archaeological lead, while the other was composed of natural modern lead. The significance of employing two crystals lies in their identical dimensions and proximity, resulting in similar environmental background exposure. Their distinct internal radioactivities, particularly associated with 210 Pb, introduce a distinguishing factor between the spectra measured in the two detectors. Our detection method includes achieving clear particle identification through the relative amplitudes of light and heat signals for both crystals. This report compares the electron-induced spectra within energy regions both below and above the endpoint of 210 Bi beta decay. This comparative study provides valuable insights into an exact measurement of the 210 Bi decay spectrum, forbidden non-unique beta decay. [ABSTRACT FROM AUTHOR]

The main aim of this study was to investigated background levels of radioisotopes 137Cs (Cesium), 232Th (Thorium), 40K (Potassium), and 226Ra (Radium) in all samples taken from two important rivers of the Sinop province prior to the nuclear power plant. The sediment samples were taken from the Karasu (80 km) and Kabalı (51.3 km) rivers at 2 km distances in July 2019, the month with the least precipitation, and in December 2018, the month with the most precipitation, before the nuclear power plant built in the Sinop province became active. The concentrations of 226Ra, 232Th, 137Cs and 40K in the collected sediment samples were measured using a high purity germanium detector (HPGe). The activity concentrations of 226Ra, 232Th, 137Cs and 40K in the sediment samples taken from the Karasu River in December and in July were in the range of 3.08–29.40 Bq/kg, 2.95–19.10 Bq/kg, 0.35–61.13 Bq/kg and 54.83–495.02 Bq/kg, respectively. In the sediment samples collected from the Kabalı River in December and in July, 226Ra, 232Th, 137Cs and 40K activity concentrations were in the range of 5.79–25.65 Bq/kg, 3.35–19.55 Bq/kg, 0.97–7.23 Bq/kg and 141.66–446.77 Bq/kg, respectively. Some risk parameters were also calculated to assess radiological hazards. These values were found to be lower than the world averages recommended by international organizations. Based on all the results obtained, it can be concluded that the examined samples do not pose a radiological risk. [ABSTRACT FROM AUTHOR]

Labuan, Miri, Kundasang and Raub regions of Malaysia have very different geological formations and settings that could result in different levels of natural radioactivity. Hence, this study determines the influence of different geological formations on radioactivity in these locations using field measurements, petrology and geochemistry. A total of 141 gamma dose rates and 227 beta flux measurements were collected using Polimaster survey meters (PM1405) in these four regions. The gamma dose rate values range from 0.37 to 0.05 µSv/h with a mean value of 0.11 µSv/h. Beta flux values range from 3.46 to 0.12 CPS with a mean value of 0.57 CPS. Mineralogy and elemental composition of the different rock types were analysed using thin-section petrography, XRD, ICP and pXRF methods. Felsic igneous rocks such as syenite and granite have higher natural radioactivity and contain more radionuclide-bearing minerals such as apatite, zircon, allanite, K-feldspar, titanite, muscovite and biotite. Metamorphic rocks have the second highest natural radioactivity and contain fewer radioactive minerals. The natural radioactivity of sedimentary rocks mostly depends on their clay content. The gamma dose rate maps show that igneous and metamorphic regions around Raub have higher radioactivity compared to the sedimentary-dominated regions around Miri and Labuan. Annual effective dose (AED) and excess lifetime cancer risk (ELCR) were calculated to evaluate the potential health risk for inhabitants of these regions. Labuan and Miri are considered to be safe zones with respect to natural radioactivity as the results show little to no risk for the public, compared with the Raub region, which is medium to high risk. [ABSTRACT FROM AUTHOR]

Background: Fatty acid uptake can be measured using PET and 14-(R,S)‐[18F]fluoro‐6‐thia‐heptadecanoic acid ([18F]FTHA). However, the relatively rapid rate of [18F]FTHA metabolism significantly affects kinetic modeling of tissue uptake. Thus, there is a need for accurate chromatographic methods to analyze the unmetabolized [18F]FTHA (parent fraction). Here we present a new radiometabolite analysis (RMA) method, with comparison to a previous method for parent fraction analysis, and its use in a test-retest clinical study under fasting and postprandial conditions. We developed a new thin-layer chromatography (TLC) RMA method for analysis of [18F]FTHA parent fraction and its radiometabolites from plasma, by testing stationary phases and eluent combinations. Next, we analyzed [18F]FTHA, its radiometabolites, and plasma radioactivity from subjects participating in a clinical study. A total of 17 obese or overweight participants were dosed with [18F]FTHA twice under fasting, and twice under postprandial conditions and plasma samples were obtained between 14 min (mean of first sample) and 72 min (mean of last sample) post-injection. Aliquots of 70 plasma samples were analyzed using both methods, enabling head-to-head comparisons. We performed test-retest and group comparisons of the parent fraction and plasma radioactivity. Results: The new TLC method separated seven [18F]FTHA radiometabolite peaks, while the previous method separated three. The new method revealed at least one radiometabolite that was not previously separable from [18F]FTHA. From the plasma samples, the mean parent fraction value was on average 7.2 percentage points lower with the new method, compared to the previous method. Repeated [18F]FTHA investigations on the same subject revealed reproducible plasma SUV and parent fractions, with different kinetics between the fasted and postprandial conditions. Conclusions: The newly developed improved radio-TLC method for [18F]FTHA RMA enables accurate parent fraction correction, which is required to obtain quantitative data for modelling [18F]FTHA PET data. Our test-retest study of fasted and postprandial conditions showed robust reproducibility, and revealed clear differences in the [18F]FTHA metabolic rate under different study settings. Trial registration: EudraCT No: 2020-005211-48, 04Feb2021; and Clinical Trials registry NCT05132335, 29Oct2021, URL: https://classic.clinicaltrials.gov/ct2/show/NCT05132335. [ABSTRACT FROM AUTHOR]

A pilot survey in the Central Garhwal Himalayan region, India, assessed radon and thoron inhalation doses using RADUET, CR39 detectors during January to October 2013. Detectors were deployed for 95, 101, and 92 days in winter, summer, and in the rainy season respectively. Highest 222Rn concentration (260 ± 13 Bqm−3) was in cemented categories, followed by 170 ± 8 and 190 ± 10 Bqm−3 in wood-stone dwellings. Wood-mud categories had lower levels (116 ± 6 to 128 ± 8 Bqm−3). Despite significant 222Rn concentration, analysis of seasonal radiation exposures (EECTn and Feq) with short-lived decay products showed reduced doses in winter months ranging from 2.97 (± 0.31) to 6.91 (± 0.32) Bqm−3. [ABSTRACT FROM AUTHOR]

The main objective of this study was to assess the natural radiation dose and radiological risk around Lake Monoun and some surrounding localities. A total of 28 soil samples were analyzed using gamma-ray spectrometry based on a High-Purity Germanium detector. The activity concentrations of primordial radionuclides (226Ra, 232Th, and 40K) and the corresponding health hazard risks were determined. The average value of air absorbed dose rate and the total excess lifetime cancer risk were found to be 68.32 nGyh−1 and 1.86 × 10–3. These recorded average values were above the world average value reported by UNSCEAR 2000. RESRAD-OFFSITE computer code was used to evaluate the long-term radiological risk from the study area. The RESRAD simulation data of excess cancer risk was above the world limit of 1.45 × 10–3 until 100 years. The obtained results showed insight into public exposure and could be used as baseline data for future investigations. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of estimating the radioactivity of radiopharmaceuticals using shielded syringes. The radioactivities of 99mTc-MDP, 99mTc-HMDP, 99mTc-ECD, 99mTc-MAG3, and 123I-IMP were measured using a dose calibrator. Correlation coefficients and regression equations were obtained from the radioactivity in the shielded and unshielded syringes. 99mTc-MDP was also measured for residual radioactivity after the administration. The correlation coefficients of 99mTc-MDP, 99mTc-HMDP, 99mTc-ECD, 99mTc-MAG3, and 123I-IMP were rs = 0.9998, rs = 0.9997, rs = 0.9999, rs = 0.9998, and rs = 0.9888, respectively. The regression equations were y = 0.0364x + 0.0913, y = 0.0349x + 0.0273, y = 0.0343x − 0.0018, y = 0.0522x + 0.1215, and y = 0.0383x + 0.0058, respectively. The correlation coefficient for the residual radioactivity of 99mTc-MDP was rs = 0.9887 and the regression equation was y = 0.1505x + 0.0853. The radioactivity of 99mTc- and 123I-labeled radiopharmaceuticals in shielded syringes was accurately measured. It was suggested that the measuring shielded syringes could provide an estimate of the actual radioactivity. [ABSTRACT FROM AUTHOR]

Purpose: Enzymolysis clearance strategy, characterized by releasing the non-reabsorbable radioactive fragment under the specific cleavage of enzymes, is confirmed to be a safe and effective way to reduce the renal radioactivity accumulation in mice. However, the effectiveness of this strategy in humans remains unknown. Human epidermal growth factor receptor 2 (HER2) is overexpressed in various types of tumors, and radiolabeled HER2 Affibody is believed to be an attractive tool for HER2-targeted theranostics. However, its wide application is limited by the high and persistent renal uptake. In this study, we intend to validate the effectiveness of enzymolysis clearance strategy in reducing renal accumulation by using a modified HER2 Affibody. Materials and methods: A new HER2 Affibody ligand, NOTA-MVK-ZHER2:2891, containing a cleavable Met-Val-Lys (MVK) linker was synthesized and labeled with 68Ga. The microPET imaging study was performed in SKOV-3 tumor mice to assess the uptakes of the control ligand and the MVK one in tumors and kidneys. Seven healthy volunteers were included for biodistribution and dosimetric studies with both the control and MVK ligands performed 1 week apart. Urine and blood samples from healthy volunteers were collected for in vivo metabolism study of the two ligands. Four HER2-positive and two HER2-negative patients were recruited for [68Ga]Ga-NOTA-MVK-ZHER2:2891 PET/CT imaging at 2 and 4 h post-injection (p.i.). Results: [68Ga]Ga-NOTA-MVK-ZHER2:2891 was stable both in PBS and in mouse serum. MicroPET images showed that the tumor uptake of [68Ga]Ga-NOTA-MVK-ZHER2:2891 was comparable to that of [68Ga]Ga-NOTA-ZHER2:2891 at all the time points, while the kidney uptake was significantly reduced 40 min p.i. (P < 0.05). The biodistribution study in healthy volunteers showed that the kidney uptake of MVK ligand was significantly lower than that of the control ligand at 1 h p.i. (P < 0.05), with the SUVmean of 34.3 and 45.8, respectively, while the uptakes of the two ligands in the other organs showed negligible difference. The effective doses of the MVK ligand and the control one were 26.1 and 28.7 µSv/MBq, respectively. The enzymolysis fragment of [68Ga]Ga-NOTA-Met-OH was observed in the urine samples of healthy volunteers injected with the MVK ligand, indicating that the enzymolysis clearance strategy worked in humans. The PET/CT study of patients showed that the range of SUVmax of HER2-positive lesions was 9.4–21, while that of HER2-negative lesions was 2.7–6.2, which suggested that the MVK modification did not affect the ability of ZHER2:2891 structure to bind with HER2. Conclusion: We for the first time demonstrated that enzymolysis clearance strategy can effectively reduce renal radioactivity accumulation in humans. This strategy is expected to decrease renal radiation dose of peptide and small protein-based radiotracers, especially in the field of radionuclide therapy. [ABSTRACT FROM AUTHOR]

A baseline study was carried out to determine the activity concentrations of 238U, 232Th-decay series and 40K in marine sediment. Surface sediments were taken from 29 sample stations. The average activity concentrations(Bq kg−1) of 238U (20.2), 232Th (7.4) and 40K (70.0) were below the world average with an annual effective dose (43.07 µSv y−1) unlikely to pose significant radiological risk. The ERICA tool application confirmed the potential dose rate to marine biota from radioactivity in sediments is unlikely to pose an appreciable risk. The findings offer a crucial radiological risk profile characteristic that may be used to compare current radioactivity levels in marine ecosystems to those in the future. [ABSTRACT FROM AUTHOR]

The activity concentrations of 226Ra, 232Th and 40K in four common types of building materials (carbonate, quartz, clay and granite) in North Vietnam were determined by HPGe gamma-ray spectrometry. The average activity of these radionuclides were 15, 17 and 213 Bq kg−1 for carbonate; 43, 35 and 462 Bq kg−1 for quartz; 80, 99 and 824 Bq kg−1 for clay; and 98, 198 and 1440 Bq kg−1 for granite. The results showed significant differences in the activities of these radionuclides in different building materials as follows: ACarbonate < AQuartz < AClay < AGranite. The radioactivity of building materials originated from granite and clay are high, while those observed for ones derived from carbonate and quartz are low. Regarding radiation hazard indices, granite exceeded the recommended value, while carbonate fell below this maximum. [ABSTRACT FROM AUTHOR]

Radiological hazard assessment is an important task. The natural radionuclides in 88 surface soil samples in/surrounding high-level natural radiation areas were measured using a high-purity germanium gamma-ray detector. The 226Ra, 238U, 232Th, and 40K activities varied from 60.4 to 655, 59.3 to 643, 71.2 to 886, and 252 to 745 Bq/kg respectively. The highest radionuclides concentration was found in rare earth element mines, followed by uranium and metallic mines. There was an equilibrium between 238U and 226Ra with 238U/226Ra ratios equal to 1.01. The radiation hazard indices in the study soil samples were far higher than the world average values. [ABSTRACT FROM AUTHOR]

As a decay product of uranium series, 210Pb spreads widely in the nature and imposes strong radiological and chemical toxicity. It is vital to establish reliable and efficient radioanalytical methods for 210Pb determination to support environment and food radioactivity monitoring programs. This article critically reviews analytical methods developed for determining 210Pb in environmental and biological samples, especially new development in recent years. Techniques applied throughout different analytical steps including sample pretreatment, separation, purification, and detection are summarized and their pros and cons are discussed to provide a holistic overview for 210Pb environmental and biological assay. [ABSTRACT FROM AUTHOR]

In the twenty-first century, numerous forms of pollution have adversely impacted freshwater and the entire aquatic ecosystem. The higher population density in urban areas also contributes to increased releases of substances and thermal contaminants, significantly stressing the ecosystem of industrial companies. This study aimed to assess the potential pressure of industrial and municipal activities on water quality, radioactivity levels, and biological diversity, focusing on the consequences of radionuclides on periphytic diatom communities. Furthermore, the environmental impact of pollutants will be evaluated to monitor the ecological condition of the Ismailia Canal. Chemical analyses employed various instruments and methods to identify and quantify matter, with radionuclide elements measured by gamma spectrometry and diatoms counted and identified by inverted microscopy. Our results revealed that the canal was classified as excellent for irrigation, aquatic life, and drinking water based on FAO, CCME, and EWQS water quality indices, with high nutrient levels at Abu Za'baal fertilizer company. The activity concentration of 226Ra-series, 232Th-series, and 40K in the water and sediment samples for two seasons was within the guideline values, except for a few stations in the zone [B] (the industrial zone). Fertilizer samples (raw material) showed a high value of the 226Ra-series activity. Diatom community structure significantly varied across the different canal locations regarding the presence or absence of industrial activities, with no discernible variations between the study seasons. A specific variety of algal species was found to be predominant at the highest radioactive sites. Redundancy analysis (RDA) showed a significant correlation between parameters (pH, Na, TDS, PO4, SO4, SiO2, K, and CO3), radionuclides, environmental conditions, and the composition of the diatom community, especially in the area affected by industrial discharges. Moreover, the radiological hazard index in water and sediment remained below the maximum for two seasons. This research provides valuable data and information for communities and decision-makers, suggesting the strategic use of phycoremediation as a water biotreatment process to protect the valuable economic resources of the Ismailia Canal. [ABSTRACT FROM AUTHOR]

The possibility of tritium introduction into graphene oxide (GO) by tritium thermal activation method was demonstrated. It was established that, in order to produce the highest possible specific radioactivity, thin films of GO with a thickness of 5.6 mg/m2 must be treated with tritium atoms. The experiment conducted at 77 K showed a number of advantages. GO was processed with tritium atoms, the resulting specific activity of [3H]GO reached 2.6 Ci/mg in term of the weight of the initial GO (0.7 Ci/mg after removal of the labile tritium). Specific energy release of [3H]GO with this specific activity is 22.3 W/kg, which is quite sufficient for its application as a component of a nuclear battery. [ABSTRACT FROM AUTHOR]

In the early years of nuclear explosion monitoring, experts used downwind detections with meaningful ratios of radioactive species to identify an explosion. Today's reality is sparse networks of radionuclide monitoring stations looking for weak signals. Analysts need to discriminate between industrial background radioactivity and nuclear explosion signals, even using the detection of one isotope. Aerosol and xenon measurements potentially related to nuclear tests in 2006 and 2013 announced by the Democratic People's Republic of Korea and from worldwide civilian background radioactivity are considered when defining radionuclide detection anomalies to objectively guide the use of limited analyst resources and reduce the possibility of not detecting nuclear explosions. [ABSTRACT FROM AUTHOR]

The present study investigates to incorporate spiked sulfate solution simulate into polymer–cement composite (PCC) based on recycled expanded polystyrene foam. The main aim is to convert the waste stream into leach resistance solid forms able to slow down or even to retard the back release of hazardous radionuclides to the surrounding. Effective parameters e.g. leachant medium, temperature, radioactivity contents, leachant volumes and radionuclides speciation versus the leaching time were studied. The incremental leach rate (Rn, cm/day) and the leach index (Lx) were evaluated for the final waste form after 145 days. The experimental results revealed that the Lx for the all variances can fulfil the waste acceptance criteria for the disposal facility and are above the threshold value of 6. Moreover, leach rate percentages for Cs-134 and Co-60 were not exceeding 2%. The acquired data, based on lab leaching experiments, can recommend the developed PCC under consideration for solidification of radioactive sulphate waste stream safely. [ABSTRACT FROM AUTHOR]

The effects of reaction temperature, reaction time, NaOH concentration and dosage on the hydrolysis rate of TBP were investigated. With the optimized conditions, the hydrolysis rate of TBP reached more than 99.5%. The reaction temperature is the greatest impact factor of TBP hydrolysis. As the hydrolysis reaction proceeded, TBP was first hydrolyzed into NaDBP, and then further hydrolyzed into Na2MBP. Three phases were formed after alkaline hydrolysis of TBP/n-dodecane, the n-dodecane (≈70% v%) was at the top phase that could be recycled or reused. [ABSTRACT FROM AUTHOR]

Radioactive particles often contain very high radioactivity concentrations and are widespread. They pose a potential risk to human health and the environment. Their detection, quantification, and characterization are crucial if we are to understand their impact. Here, we present the use of a real-time autoradiography gaseous detector (using parallel ionization multiplier) to expedite and improve the accuracy of radioactive particle screening in complex environmental samples. First, standard particles were used to assess the detector capabilities (spatial resolution, spectrometry, and artefact contributions), then, we applied the technique to more complex and environmentally relevant samples. The real-time autoradiography technique provides data with a spatial resolution (≲100 µm) suitable for particle analysis in complex samples. Further, it can differentiate between particles predominantly emitting alpha and beta radiation. Here, the technique is applied to radioactive cesium-rich microparticles collected from the Fukushima Daiichi nuclear exclusion zone, showing their accurate detection, and demonstrating the viability of real-time autoradiography in environmental scenarios. Indeed, for more complex samples (radioactive particles in a less radioactive heterogeneous background mix of minerals), the technique permits relatively high selectivity for radioactive particle screening (up to 61.2% success rate) with low false positive percentages (~ 1%). [ABSTRACT FROM AUTHOR]

The reaction 243 Am (54 Cr , x n) 297 - x 119 has been suggested as a potential candidate for synthesizing the new element with Z = 119 in recent years. α decay serves as a powerful tool for identifying the new elements or nuclides. Using an improved density-dependent cluster model, we have investigated the α -decay chains of 293 - 295 119 isotopes. Additionally, we have studied the probable cluster decay half-lives for these isotopes. The results indicate that 14 C as well as 86 Kr are the most likely emitted clusters for 293 - 295 119rter half-lives compared to other cluster emissions. It is expected that the proposed theoretical predictions for α -decay chains and cluster radioactivity could provide a new perspective for future experiments. [ABSTRACT FROM AUTHOR]

Radioactive aerosols produced by nuclear accidents and decommissioning of nuclear power plants would cause tremendous radioactive damage to the environment and human body. The development of a radioactive aerosol suppressant is of great significance in the treatment of radioactive aerosols. In this study, a three-dimensional biomass-based polymer pectin-g-acrylic acid-acrylamide (pectin-g-poly (AA-co-AM)) SAP with high water absorbency and high agglomeration was prepared by solution polymerization. The results showed that the water absorbency of pectin grafted with acrylic acid and acrylamide reached 1064 g/g. Furthermore, under the synergistic effect of water absorption and agglomeration of the material, the sedimentation efficiency of simulated radioactive aerosol by 30 min after using suppressant is 91.21%. [ABSTRACT FROM AUTHOR]

Banana, a staple food, could be consumed daily for its nutritional value. In the present study, banana samples were collected from Kerala and Delhi NCR and gross beta-gamma activities (Bq kg−1) were estimated in order to understand the contribution of radiation levels to human body due to consumption of banana. Activities of radionuclides such as 40K and 232Th in banana samples were measured using gamma ray spectrometry. Effective dose rate by ingestion to an individual from banana consumption was determined and results were compared with the effective dose rate to general public by International Commission on Radiological Protection recommendations. [ABSTRACT FROM AUTHOR]

This study aimed to assess the concentrations of 210Po and 210Pb in various tobacco samples from Palestine and Jordan. Cigarette smoking is recognized as a significant contributor to the radiation dose received by individuals, primarily due to the elevated levels of 210Pb and 210Po found in tobacco. The analysis revealed that the average concentrations of 210Po in locally sourced tobacco and cigarette samples in Palestine are 16.8 ± 2.3 mBq/g and 18.5 ± 2.0 mBq/g, with a total average of 17.8 ± 7.4 mBq/g (15.5 mBq/cigarette). Similarly, the average concentrations of 210Pb in these samples are 18.5 ± 2.6 mBq/g and 20.3 ± 2.2 mBq/g, with a total average of 19.6 ± 8.1 mBq/g (17.0 mBq/cigarette). In Jordan, the average concentrations of 210Po in cigarette samples and narghile tobacco are 20.1 ± 2.4 mBq/g and 18.3 ± 4.1 mBq/g, with a total average value of 19.6 ± 9.9 mBq/g (18.0 mBq/cigarette), while the average concentrations of 210Pb are 22.2 ± 2.6 mBq/g and 20.2 ± 4.5 mBq/g, with a total average value of 21.6 ± 10.8 mBq/g (19.9 mBq/cigarette). The annual effective doses resulting from inhalation were calculated for smokers of these samples. The findings revealed that the levels of 210Po and 210Pb radioactivity in certain investigated samples exceeded the results of studies in many countries of the world. The associated effective doses per year from smoking for all brands products in Palestine range from 34.7 μSv/y to 186.5 μSv/y with an average of 109.5 μSv/y, while in Jordan 54.5 μSv/y to 289.1 μSv/y with an average of 130.9 μSv/y. [ABSTRACT FROM AUTHOR]

The Kanyakumari coast is known to be a high background natural radiation area due to the placer deposits of heavy minerals such as ilmenite, monazite, and rutile. The Kanyakumari river sediments that could be the source of the elevated amounts of natural radionuclides in the coastal sands have been studied in this paper. The activity concentrations of primordial radionuclides 226Ra, 232Th, and 40K were determined using high-purity germanium (HPGe) gamma-ray spectrometry. The mean activity concentrations of 226Ra, 232Th, and 40K were found to be 75 Bq kg−1, 565 Bq kg−1, and 360 Bq kg−1, respectively. The mean absorbed dose rate was 395 nGy h−1. Radiological hazard parameters were studied and compared with the world average values. The contribution of 232Th to the total dose rate was found to be higher than that of the two other radionuclides. The high mean ratio of 232Th/226Ra suggested an enrichment of 232Th and the occurrence of 226Ra leaching due to an oxidizing environment. Principal component analysis (PCA) was carried out for the radionuclides in order to discriminate the source of the sediments. This study provides new insights into the distribution of natural radionuclides in sediments of rivers and streams. [ABSTRACT FROM AUTHOR]

The estimation of exposures to humans from the various sources of radiation is important. Radiation hazard indices are computed using procedures described in the literature for evaluating the combined effects of the activity concentrations of primordial radionuclides, namely, 238U, 232Th, and 40 K. The computed indices are then compared to the allowed limits defined by International Radiation Protection Organizations to determine any radiation hazard associated with the geological materials. In this paper, four distinct radial basis function artificial neural network (RBF-ANN) models were developed to predict radiation hazard indices, namely, external gamma dose rates, annual effective dose, radium equivalent activity, and external hazard index. To make RBF-ANN models, 348 different geological materials' gamma spectrometry data were acquired from the literature. Radiation hazards indices predicted from each RBF-ANN model were compared to the radiation hazards calculated using gamma spectrum analysis. The predicted hazard indices values of each RBF-ANN model were found to precisely align with the calculated values. To validate the accuracy and the adaptability of each RBF-ANN model, statistical tests (determination coefficient (R2), relative absolute error (RAE), root mean square error (RMSE), Nash–Sutcliffe Efficiency (NSE)), and significance tests (F-test and Student's t-test) were performed to analyze the relationship between calculated and predicted hazard indices. Low RAE and RMSE values as well as high R2, NSE, and p-values greater than 0.95, 0.71, and 0.05, respectively, were found for RBF-ANN models. The statistical tests' results show that all RBF-ANN models created exhibit precise performance, indicating their applicability and efficiency in forecasting the radiation hazard indices of geological materials. All the RBF-ANN models can be used to predict radiation hazard indices of geological materials quite efficiently, according to the performance level attained. [ABSTRACT FROM AUTHOR]

Miners, factory workers, traders, end-users, and foodstuff consumers all run the risk of encountering health hazards derived from the presence of elevated levels of radiation in fertilizers, as these groups often come into direct or indirect contact with fertilizers as well as raw materials throughout various linked processes such as mineral extractions, fertilizer production, agricultural practices. A total of 30 samples of various kinds of fertilizer produced in different factories in Dhaka megacity were analyzed to quantify the concentrations of primordial radionuclides using HPGe detector. Among the analyzed samples, average (range) concentration of 40K was found to be 9920 ± 1091 (8700 ± 957–11,500 ± 1265), 9100 ± 1001 (8600 ± 946–9600 ± 1056), 2565 ± 282 (2540 ± 279–2590 ± 285), and 3560 ± 392 (2620 ± 288–4500 ± 495) Bq/kg in the samples of Muriate of Potash Fertilizer, Sulphate of Potash Fertilizer, Humic Acid Fertilizer, and NPKS Fertilizer, respectively. Elevated concentration of 226Ra was found in Triple Super Phosphate Fertilizer with a mean (range) of 335 ± 37 (290 ± 32–380 ± 42) Bq/kg. The higher activity of 40K can be linked to the greater levels of elemental potassium in phosphate fertilizer. Elevated concentrations of radionuclides may also result from variations in chemical processes as well as the local geology of the mining areas where the raw materials were extracted for fertilizer production. Numerous fertilizer brands surpass prescribed limits for various hazardous parameters, presenting significant health risks to factory workers, farmers, and consumers of agricultural products. This study provides baseline information on the radioactivity of fertilizers, which could be used to develop mitigation methods, establish national fertilizer usage limits, justify regulatory frameworks, and raise public awareness of fertilizer overuse. The findings of the study could potentially help to explore the impact of fertilizer on the food chain. [ABSTRACT FROM AUTHOR]

Natural radioactive concentration assessment was conducted on sediment, water, and biota obtained on Vaan and Koswari islands in the Tuticorin group of islands, Tamil Nadu, India. For biotic and abiotic components, radiation profiles such as gross alpha, beta, primordial radionuclide, polonium, and lead analyses were performed. The gross α and β range from BDL to 15.18 ± 1.7 Bq/kg and 40.43 ± 4.9 Bq/kg to 105.12 ± 11.7 Bq/kg, respectively. Primordial radionuclides were analyzed using Nal(TI)-based scintillator with PC-MCA, and the concentrations ranged from 13.43 ± 3.3 Bq/kg to 30.97 ± 9.6 Bq/kg with a mean of 21.31 ± 2.7 Bq/kg for 238U; for 232Th, the values ranged from 11.09 ± 2.6 Bq/kg to 33.55 ± 9.5 Bq/kg with an average value of 23.89 ± 3.7 Bq/kg; and for 40 K, the values are 93.33 ± 27.3 Bq/kg to 219.91 ± 39.6 Bq/kg with an average value of 148.27 ± 21.7 Bq/kg. The present study values are lesser than the world average values. 210Po and 210Pb concentrations with an average value were determined to be 33.13 Bq/L and 16.56 Bq/L, 47.55 Bq/L and 22.37 Bq/L in the water sample, and 50.437 Bq kg1 and 62.012 Bq kg1, 46.99 Bq/kg and 58.625 Bq/kg in sediments of Vaan island and Koswari island. The concentrations of 210Po and 210Pb of Pogonias cromis were 19.27 ± 1.5 Bq/kg and 8.27 ± 1.01 Bq/kg, Belonidae 28.54 ± 2.4 Bq/kg and 18.32 ± 2.3 Bq/kg, Lepisosteidae 18.68 ± 1.4 Bq/kg and 11.17 ± 1.8 Bq/kg. The committed effective dosage was determined to be 35.74–54.61 µSv/y for 210Po and 25.39–56.25 µSv/y for 210Pb, in which the 210Pb value is lower; however, the 210Po value is higher than the global average value. The annual committed effective dosage as well as the radiological hazard indices were assessed and found to be much below the global average and the recommended limit, respectively. This research provides an extensive analysis of natural background radiation and establishes a baseline report on the radiological profile of biotic and abiotic factors in the Tuticorin group of islands, namely Vaan and Koswari, in Tamil Nadu, India. [ABSTRACT FROM AUTHOR]

Naturally occurring radioactive materials (NORMs: 232Th, 226Ra, 40K) can reach our respiratory system by breathing of road dust which can cause severe health risks. Targeting the pioneering consideration of health risks from the NORMs in road dust, this work reveals the radioactivity abundances of NORMs in road dust from a megacity (Dhaka) of a developing country (Bangladesh). Bulk chemical compositions of U, Th, and K obtained from neutron activation analysis were converted to the equivalent radioactivities. Radioactivity concentrations of 226Ra, 232Th, and 40K in road dust ranged from 60–106, 110–159, and 488–709 Bq kg−1 with an average of 84.4 ± 13.1, 126 ± 11, and 549 ± 48 Bq kg−1, respectively. Estimated 226Ra, 232Th, and 40K radioactivities were, respectively, 1.7–3.0-, 3.7–5.3-, and 1.2–1.8-folds greater than the affiliated world average values. Mechanistic pathway of NORMs' enrichment and fractionation relative to the major origin (pedosphere) were evaluated concerning the water logging, relative solubility-controlled leaching and translocation, climatic conditions, and aerodynamic fractionations (dry and wet atmospheric depositions). Computation of customary radiological risk indices invokes health risks. Noticing the ingress of NOMR-holding dust into the human respiratory system along with the associated ionizing radiations, the computed radiological indices represent only the least probable health hazards. Nevertheless, in real situations, α-particles from the radioactive decay products of 232Th and 238U can create acute radiation damages of respiratory system. Policymakers should emphasize on limiting the dust particle evolution, and public awareness is required to alleviate the health risks. [ABSTRACT FROM AUTHOR]

The radioactive concentrations of 40K, 232Th and 226Ra in 11 intertidal sediment cores in the Red River Delta were determined, and radiological hazard indices for environmental risk were assessed. The values of 40K, 232Th and 226Ra activity were 656 Bq/kg, 49.8 Bq/kg and 37.0 Bq/kg, respectively. The values of radiological hazard indices such as radium equivalent activity (Raeq), absorbed dose rate (ADR), equivalent annual effective dose (AEDE), representative gamma index (Iγr), index active use, external hazard index (Hex), annual gonadal equivalent dose (AGDE) were 158.7 Bq/kg, 74.5 nGy/h, 0.09 mSv/year, 1.18, 1.0, 0.40, and 496.4 µSv/year, respectively. The results obtained of this study showed that eleven sediment cores can be divided into two groups, of which the radioactive concentrations of 40K, 232Th and 226Ra in group 2 were higher than in group 1, and the concentration of radionuclides in sediments was higher than the global average, except for 226Ra in group 1. The ADR, AEDE, Iγr and AGDE indices were above UNSCEAR's recommended levels for both groups. The results of this study show that sediments have the potential to impact organisms in the intertidal zone and are safe for use as construction materials. [ABSTRACT FROM AUTHOR]

Nuclear grade aluminum capsules (AA-1070) was filled with 2 mg, 4 mg, 6 mg of target Sc2O3. The irradiation process of the capsule was performed in the Central Irradiation Position (CIP) G.A Siwabessy research reactor for 58.61 h. At the end of irradiation, 46Sc radioactivity was 26.67; 57.81; 85.48 mCi/capsule. The SS-316 capsule swab test, its was found that 46Sc radioactivity contamination was 2.198 Bq, 0.089 Bq and 0.218 Bq which were declared free of contamination. The gamma energy attenuation test for the thickness of the SS-304 plate, indicating that there is significant relationship between plate thickness and 46Sc gamma energy intensity. [ABSTRACT FROM AUTHOR]

Natural radioactivity (226Ra, 232Th, and 40K) concentrations were determined in sand samples collected from various beaches in Kadıköy-Istanbul (Turkey) at 12 sampling point for the evaluation of radiological parameters such as radiological equivalent activity and excess lifetime cancer risk. The activity concentrations of 226Ra, 232Th, and 40K were found to range between 21.08 and 49.19 Bqkg−1, 20.51–49.92 Bqkg−1, and 173.70–554.16 Bqkg−1, respectively. The selection of İstanbul as the study area is based on its high population density, indicating an increased vulnerability to potential negative effects of radiation exposure. [ABSTRACT FROM AUTHOR]

The results of assessing the dose of external and internal irradiation of the tree tier of pine stands growing on the northern trace of the Belarusian sector of the 30-kilometer zone around the Chernobyl nuclear power plant at the present stage are presented. It was found that, in the most polluted experimental sites, the total dose of external and internal irradiation of the stand can reach 160 mGy/year. It is also shown that internal irradiation is formed by beta radiation of radionuclides accumulated by aboveground phytomass, its contribution to the total dose can be 80%. The external irradiation of the stand is determined by the γ-radiation of 137Cs located in the soil. The results obtained are important for understanding the processes of formation of radiation-induced effects and assessing the effects of irradiation of living organisms. [ABSTRACT FROM AUTHOR]

A dynamic mathematical model of the accumulation of radionuclides in the marine biota of Stepovoi Bay was carried out for the scenario of a hypothetical accident with a spontaneous chain reaction with a submerged K-27 submarine. The dynamic model MARINA II was used to calculate the transfer of radionuclides with water masses and the transition to the bottom sediments of the bay. The modeling results were applied to calculate the dynamics of the radiation dose rate for the marine biota of Stepovoi Bay and to assess the environmental risk for the hypothetical accident scenario considered. The predicted radioactive contamination of water is determined mainly by 137Cs and 90Sr, and contamination of bottom sediments, by 137Cs, 90Sr, and 151Sm. The averaged contamination of sediments by 137Cs in this scenario is predicted at a level that is significantly lower than the criterion for attribution to solid radioactive waste. Model assessments have shown that the maximum levels of accidental 137Cs and 90Sr in the fish of Stepovoi Bay was reached one year after a single release, and it does not exceed the established hygienic standards. The highest risk index in the accident scenario considered was estimated for a marine mammal (provided that the animal is permanently located in the bay) and amounted to 0.07. Negative radiation effects are not expected to occur for the ecosystem of StepovoI Bay at this level of environmental risk. The obtained value of the generalized indicator of radioecological safety indicates a weak radiation effect on the ecosystem of the bay for a marine mammal in Stepovoi Bay. [ABSTRACT FROM AUTHOR]

This letter discusses the Chinese Consensus of Nuclear Medicine (CTA) in relation to the guidelines provided by the American Thyroid Association (ATA) and European Thyroid Association (ETA) for the management of pediatric differentiated thyroid cancer (DTC). The Chinese Consensus aims to implement standardized management practices, particularly regarding 131I treatment. However, there is a lack of evidence-based clinical data on factors such as patient age, preparation for treatment, 131I radioactivity, subsequent treatments, and follow-up. The letter compares various aspects of the CTA consensus with the ATA and ETA guidelines, including age recommendations, indications for 131I treatment, preparation for treatment, 131I radioactivity, efficacy of treatment, successive treatments, TSH inhibition therapy, and follow-up. The goal is to improve clinical outcomes for pediatric DTC patients in China by aligning with international guidelines. [Extracted from the article]