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A first implementation of analytic gradients for spinor-based relativistic equation-of-motion coupled-cluster singles and doubles method using an exact two-component Hamiltonian augmented with atomic mean-field spin–orbit integrals is reported. To demonstrate its applicability, we present calculations of equilibrium structures and harmonic vibrational frequencies for the electronic ground and excited states of the radium mono-amide molecule (RaNH2) and the radium mono-methoxide molecule (RaOCH3). Spin–orbit coupling is shown to quench Jahn–Teller effects in the first excited state of RaOCH3, resulting in a C3v equilibrium structure. The calculations also show that the radium atoms in these molecules serve as efficient optical cycling centers. [ABSTRACT FROM AUTHOR]

Brazil nuts are well known for their extraordinarily high selenium content. For this reason, they are frequently recommended as a kind of natural selenium ‘supplement’, particularly for certain population groups such as vegetarians and vegans in regions with low soil selenium levels. Typically, an intake of one or two Brazil nuts per day is recommended. Brazil nuts, however, also stand out from other nuts in terms of their high (albeit highly variable) radium content. The radium isotopes Ra‐226 and Ra‐228 emit alpha‐ and beta‐radiation, with this type of radiation being particularly harmful when ingested. Consequently, it is important to consider radium levels in Brazil nuts before formulating recommendations for a long‐term, daily intake of these nuts. To date, however, no comprehensive overview of radium levels in Brazil nuts has been published. Therefore, a literature review without time or language restrictions was conducted, including unpublished original data from Germany. The literature review (including the German data) indicated mean Ra‐226 and Ra‐228 levels of 49 (range: 17–205) mBq/g and 67 (range: 12–235) mBq/g, respectively. Assuming a consistent daily intake of one or two Brazil nuts, this would result in an effective dose of ~88–220 μSv/year. This level of exposure appears to be neither clearly harmful nor clearly harmless. As increased radioactivity exposure (at least at higher doses) is associated with increased cancer risk, randomised controlled trials assessing the effect of Brazil nuts on cancer risk biomarkers are needed. [ABSTRACT FROM AUTHOR]

Humans are exposed to radiation by the emission of radon gas from the soil surrounding them, necessitating the assessment of the radon exhalation levels in soil. The current study measures the radium concentration and radon mass exhalation rate in 34 soil samples obtained from diverse places near the purported uranium reserves in the Sikar districts of Rajasthan state, India. The concentration of radium is measured using the NaI scintillator detector, while the mass exhalation rate of radon is estimated using a smart RnDuo detector. The measured radium content in the soil is between 10.6–47.5 Bq kg−1 with an average value of 21.7 Bq kg−1. With an average value of 20.6 mBq kg−1 h−1, the radon mass exhalation rate ranges from 5.7–74.5 mBq kg−1 h−1. A positive correlation is observed between 226Ra concentration and 222Rn mass exhalation rate. This study shows that the soil of this area is safe in terms of radium content and radon mass exhalation rates. [ABSTRACT FROM AUTHOR]

A silica-supported copolymer loaded with bis (2-ethylhexyl) phosphate was prepared and first investigated for the separation of trace radium from natural 232Th. Results showed that the adsorbent was prepared successfully with ultrahigh selectivity and ultrafast adsorption kinetics towards thorium, making the separation easy and convenient. The chemical recovery rate to radium reached 96.7%, and the decontamination factor to thorium exceeded 105. Generally, this work demonstrated the feasibility of using this material and method to directly separate 228Ra and 224Ra from 232Th, rendering it significant in the future preparation and application of 212Pb. [ABSTRACT FROM AUTHOR]

We have proposed to produce a 229Th/225Ac generator by neutron irradiation of the 228Ra target, which is a decay product from 232Th. The solutions containing 232Th and 228Ra were obtained through the thermal chemical conversion method to dissolve the ThO2. Then, the separation of 228Ra from thorium solutions through co-precipitation with magnesium was studied. It was confirmed that radium is coprecipitated by this method. It was also confirmed that the precipitated magnesium carbonate can be easily converted to magnesium oxide. The decontamination of thorium from precipitated radium was investigated, and it was found that a rough decontamination of thorium was achieved by co-precipitation methods. The decontamination of thorium depends on the chemical conversion conditions and the dissolution methods used. [ABSTRACT FROM AUTHOR]

The international GEOTRACES program has been instrumental in demonstrating how marine sediments are a critical source of dissolved Fe to the world's oceans. Here, we present dissolved iron (dFe) from the GEOTRACES North Pacific GP15 section, which, alongside other sediment‐source tracers (including dissolved δ56Fe, Mn, 228Ra, and particulate Fe), allows for identification of the dFe provenance of three distinct dFe depth maxima at the Alaskan margin. Two of these (shelf and abyssal depths) are of local Alaskan sedimentary origin. The third, a mid‐depth dFe maximum with an absence of 228Ra, is an advected signal that, based on tracer data from Western Pacific GEOTRACES transects and circulation models, must be advected from sedimentary sources on the Asian margin, ∼5,000 km away. This study illustrates the importance of measuring diagnostic sedimentary tracers like radium when assigning local margins as sedimentary sources of marine trace metal budgets. Plain Language Summary: Iron is an essential, yet limiting, micronutrient for marine primary producers, and thus influences patterns of global oceanic primary productivity and carbon exchange. In recent years, the International GEOTRACES program has highlighted that marine sediments, hydrothermal vents, and atmospheric dust all supply dissolved iron to the oceans. Here, we investigated the sources of dissolved iron to the Eastern North Pacific Ocean, using samples collected on the U.S. GEOTRACES GP15 Pacific Meridional Cruise that sailed from Alaska to Tahiti in 2018. We identified three elevated dissolved iron features close to the Alaskan continental margin, with two originating from local sedimentary sources (shelf and abyss). The third, an intermediate depth dissolved iron plume that extends south into the gyre, is not of local sedimentary origin, but instead results from long‐distance transport of dissolved iron from Asian marginal sediment sources. A critical aspect of this study is the use of multiple chemical tracers such as radium, iron, and manganese, coupled with ocean circulation models, to correctly attribute the sources of trace metals to the ocean. Key Points: Three distinct dFe maxima were identified close to the Alaskan margin at different depths. Two are of local origin (shelf and abyssal)An intermediate depth dFe plume with an absence of Mn and Ra, is a distal advected signal from Asian margin sedimentary sources (5,000 km away)A multiple tracer approach of Fe, Mn, and Ra was necessary to rule out what appeared to be a local margin source [ABSTRACT FROM AUTHOR]

Transfer factors (TFs) are widely used tools for assessing the uptake of radionuclides by plants. The literature contains numerous studies on TFs in tropical and temperate climates; however, the existing data on TFs in arid and semi-arid climates are very scarce. Furthermore, the current trend in nuclear energy expansion in countries with this type of climate necessitates knowledge of the mechanisms of radionuclide incorporation by plants as well as the TF values. For this reason, this work investigates the TFs of 238U and 226Ra in plants in a study area during the summer period under conditions equivalent to a semi-arid climate. The selected plants were Scolymus hispanicus L., Eryngium campestre L., Chenopodium vulvaria L., and Chenopodium album L., which were collected in the vicinity of a waste dump from an abandoned copper mine. The selected study area has radionuclide levels above the global average, in addition to heavy metals, as it is a waste dump from an abandoned copper mine. The range of transfer factors for 238U varied between 1.5 × 10−4 kg−1 kg−1 and 7.8 × 10−3 kg−1 kg−1, while for 226Ra, the range was between 1.8 × 10−4 kg−1 kg−1 and 4.0 × 10−2 kg−1 kg−1. The correlations found with PCA were (i) 238U with Fe and Al, and (ii) 226Ra with S, Ti, Ca, and Sr. A transfer model of 238U and 226Ra was created using multiple linear regression analysis. The model showed how 238U was related to the presence of Al, while 226Ra was related to Al, Fe, and Ti. The results obtained have allowed us to propose a model for the incorporation of 238U and 226Ra, taking into account the chemical composition of the soil. The results obtained indicate that both Scolymus hispanicus L. and Eryngium campestre L. could be utilized in phytoremediation for soils contaminated by natural radionuclides in semi-arid climates. The TFs, as well as the proposed model, allow us to expand the knowledge of the absorption of natural radionuclides by plants in regions with arid and semi-arid climates, which is necessary for the radiological risk assessment of future nuclear fuel cycle facilities. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third most commonly occurring cancer in the United States, with higher incidence rates among Black populations. Groundwater concentrations of natural radionuclides uranium and radium have seldom been investigated in relation to CRC despite their known carcinogenicity. We investigate spatial patterns of CRC by race, and in relation to groundwater concentrations of uranium and radium, testing the hypothesis that uranium and radium in groundwater might differentially contribute to incident CRC in Black and White populations in counties of Georgia, USA. Black populations showed a higher incidence of CRC than White populations; the median incident rate difference was 9.23 cases per 100,000 (95% CI: 2.14, 19.40). Spatial cluster analysis showed high incidence clusters of CRC in similar regions for Black and White populations. Linear regression indicated there are, on average, 1–2 additional cases of colorectal cancer in counties with higher levels of radium in their groundwater, irrespective of race. Uranium was not associated with CRC. This ecologic study suggests that radium in groundwater may be linked with increased incidence of CRC, although it did not explain higher CRC incidence rates in Black populations. Further studies are needed to verify this association given the inherent limitations in the ecologic study design and the crude exposure assessment. [ABSTRACT FROM AUTHOR]

Radioactive radium (Ra) mainly comes from the mining and milling of uranium and other metal or non-metal mines, phosphate production and fertilizer use, production of oil and gas, coal combustion, wastewater treatment, and various wastes from the above activities, which is ubiquitous in the environment. Phytoremediation is a green and cheap remediation technology for metal/radionuclide-contaminated sites. Radium is often of particular interest and there are many literatures on parameters of Ra concentration in plants and transfer factors from soil to plant from a radiological impact assessment point of view. However, review articles on phytoremediation of Ra-polluted soil are relatively few. This review focused on radium-polluted soil phytoremediation, involving two main strategies of phytoextraction and phytostabilization, which covered the potential (hyper)accumulators for Ra, characteristics of Ra uptake from soil by plants, influencing factors, and phytostabilization application. In future research works, more attention should be paid to the deep insights and mechanism researches of Ra uptake/immobilization by plants. This review will deepen the understanding of the relationship of radium-soil-plants, and to enhance the potential application of phytoremediation as an alternative treatment technology for remediation of Ra-polluted soil site. [ABSTRACT FROM AUTHOR]

Targeted alpha therapy (TαT) represents an emerging and cutting-edge treatment option for patients dealing with highly challenging metastatic cancer diseases. Critically, the limited supply of alpha-particle-emitting radionuclides, so-called alpha in vivo nanogenerators, hampers wider utilization of TαT in clinical settings. This could effectively be circumvented by alternative production routes, including straightforward purification and reformulation strategies. Radionuclide generators offering great potential in simple and robust elution strategies can be provided that still adhere to high radioisotopic, radionuclidic, and radiochemical purity criteria. This study takes a first step towards novel separation strategies by providing additional sources of alpha in vivo nanogenerators for TαT through experiments with various metal surrogates. With different systems, 232Th/natBa was used as a radionuclide generator analogue to 227Th/223Ra, and 232Th/natBa/natLa was used as a triplet analogue to 229Th/225Ra/225Ac. Three selective resins (UTEVA, TEVA, DGA-N) were evaluated for the 232Th/natBa system. Two perturbations of the best-performing resin were further evaluated using a larger diameter column and 1 week of equilibration. For the 232Th/natBa/natLa separation system, a combined column with two selective resins (TK200, TK101) was employed and evaluated. The results thus obtained pave the way for alternative separation strategies in radioactive proof-of-concept validation in the near future. [ABSTRACT FROM AUTHOR]

In the present study, natural radioactivity and radon exhalation rates of 55 stony material samples divided into three groups (Gneiss, Granite and Marble) were estimated by means of laboratory tests. The activity concentration range was found: 5.5 ± 1.3–125.5 ± 6.5 Bq.kg−1 for 226Ra, 4.4 ± 0.6–157.4 ± 8.4 Bq.kg−1 for 232Th and 35.0 ± 0.4–1093 ± 15 Bq.kg−1 for 40K. The data were used to evaluate radiation hazard parameters. The radon exhalation rate ranged from 0.17 ± 0.01 to 2.56 ± 0.20 Bq.m−2.h−1. Granite building materials show the highest radon exhalation rates while the marble group shows the lowest exhalation rates. Positive correlation coefficients of radon exhalation rate with radium concentration and porosity of the samples have been observed. This study also presents radon diffusion coefficient values determined for 50 waterproofing materials. A radon-proof ability comparison of waterproofing materials and a conclusion about material groups which can be considered very effective radon barriers were discussed. [ABSTRACT FROM AUTHOR]

This research aimed to determine the activity concentration of 226Ra in the natural radioactivity of the surface water of the Maritsa River, Türkiye. The gamma spectrometric analysis was conducted by using 3′′ × 3′′ NaI(Tl) and (HPGe) detector. Since the direct measurement method could not acquire reliable results, the mean activity concentration of 226Ra was calculated as 0.62 Bq L−1 with the "standard addition method". The mean values of the gross alpha/beta activities and the total radium alpha activity concentration were measured. The results are 0.013 Bq L−1, 0.304 Bq L−1, and 0.014 Bq L−1 respectively. [ABSTRACT FROM AUTHOR]

This study was conducted in the Najaf Governorate, Iraq, to analyze biological samples from smokers and non-smokers. Blood serum, urine, hair, and nails as a biological sample at five age groups were chosen to determine alpha emitters (222Rn, 226Ra, 218Po, and 214Po) using a CR-39 detector. The results show that the average values of radon concentrations (Bq m−3) in blood serum, urine, hair, and nails for smokers were 54 ± 19, 63 ± 20, 33 ± 9, and 40 ± 12 respectively. While, the average values of radon concentrations (Bq m−3) in blood serum, urine, hair, and nails for non-smokers were 23 ± 6, 30 ± 6, 18 ± 5, and 20 ± 6 respectively. Age and smoking affect all alpha emitters, according to the study's conclusions and comparisons. Significantly higher alpha emitters were seen in smokers compared to non-smokers (p < 0.01). Alpha emitter levels were significantly variable among age groups (p < 0.01). In smokers, greater levels were significantly linked to exposure time (p < 0.01). Smokers had greater mean values of 222Rn, 226Ra, 218Po, and 214Po in biological samples than non-smokers. Thus, it may be said that cigarette smoking is used as a biomarker of the presence of alpha emitters. [ABSTRACT FROM AUTHOR]

Background: Mucinous adenocarcinoma of the prostate (MACP) is one of the rarest variants of prostatic neoplasm, with more aggressive behavior than non-mucinous prostatic cancer. Previous studies suggested that these tumors exhibit different imaging magnetic resonance imaging (MRI) features compared with those of non-mucinous adenocarcinoma of the prostate upon which the conventional PIRADS v2.1 is based. To the best of our knowledge, this case series is the first to describe the multiparametric magnetic resonance imaging features of the MACP. Results: We presented two cases of biopsy proven mucinous adenocarcinoma of the prostate studied with multiparametric MRI. In both cases, diagnosis was late because of the different MRI features of MACP than those of the more common adenocarcinoma of the prostate. In both mpMRI, MACP appears to be hyperintense on T2WI, there was not a significant decrease in diffusivity in ADC maps and it exhibits early enhancement in DCE-MRI; the septa resulted in hypointense on T2WI compared to the PZ Conclusions: According to our experience, the conventional PIRADS v2.1 score is not suitable for mucinous prostate adenocarcinoma. MACP appears to be hyperintense on T2WI, has a lower ADC value, and exhibits early enhancement in DCE-MRI; the septa are usually hypointense on T2WI compared to the PZ. It is imperative for radiologists and urologists to be cognizant of this rare variant of prostate cancer to promptly identify and diagnose it, thereby preventing any diagnostic delays. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The results of the phase 3 ALSYMPCA trial showed that Radium-223 (Ra-223) improves overall survival (OS) and delays onset of first symptomatic skeletal event vs. placebo in patients with metastatic castration-resistant prostate cancer (mCRPC). The purpose of the REACTIVATE study was to inform the optimal placement of Ra-233 in the treatment sequence by evaluating clinical outcomes and healthcare resource utilization using real-world data from multiple Canadian provinces. METHODS: This retrospective cohort study analyzed patient outcomes according to Ra-223 placement using administrative databases of four Canadian provinces, encompassing 4301 patients with mCRPC who received at least two lines of life-prolonging therapy (LPT) for mCRPC. Outcomes included OS, event-free survival (EFS), and healthcare resource utilization. Each province was analyzed separately. RESULTS: OS, measured from the start of second-line LPT, differed between provinces: those in Ontario receiving second-line Ra-223 had a longer OS vs. those receiving it in third-line or later (hazard ratio [HR] 0.79, 95% confidence interval [CI] 0.66-0.95). There was no difference between lines of therapy in patients in British Columbia (HR 1.165, 95% CI, 0.894-1.518, p=0.2576), and OS was numerically worse but not statistically significant in patients receiving Ra-223 in second-line in Quebec (HR 1.44, 95% CI, 0.93-2.24). Other outcomes also varied across provinces, with second-line use of Ra-223 being associated with longer EFS and reduced healthcare utilization vs. third-line use in Ontario but not in Quebec. CONCLUSIONS: Significant heterogeneity exists in the management and outcomes of mCRPC between provinces, particularly regarding the placement of Ra-223 in the treatment sequence. [ABSTRACT FROM AUTHOR]

Among natural radionuclides, 226Ra and 228Ra intake can contribute considerably to radiological dose. Liquid scintillation counting offers a reliable and sensitive method for measurement in environmental (water) and biological (urine) matrices. While the determination of 226Ra in water is quite simple, its determination in urine requires a suitable radiochemical procedure. In both cases an indirect measurement of daughter 222Rn (with 218Po and 214Po) in secular equilibrium allows to determine 226Ra activity. Moreover, in presence of anthropogenic radionuclides, a sequential separation of 228Ra and 90Sr in water has been developed, isolating daughters 228Ac and 90Y in secular equilibrium in the same vial. [ABSTRACT FROM AUTHOR]

The separation procedure for Ra isotopes and 210Pb from water using the EMPORE™ radium RAD disks is very quick and convenient. However, higher levels of the chemically similar Ba in the water at least partly prohibit the uptake of Ra and 210Pb, hampering the correct determination of these radionuclides. This investigation shows that the decrease of extraction yield in dependence of the Ba mass is much slower for Ra than for 210Pb: With a Ba content ≤ 1 mg in the water sample, 226Ra could be separated completely, 210Pb, however, showed a decreasing recovery already at 0.1 mg Ba addition. [ABSTRACT FROM AUTHOR]

Environmental monitoring of external and internal radon is very important for public health. To assess the possibility of respiratory cancer, the study dealt with collecting (81) samples of sludge produced as waste from the oil industry from oil fields in Maysan Governorate, southern Iraq. The aim of the study was to determine the concentrations of radon gas ( 222Rn) and the concentration of radium, and the effective dose resulting from the release of radon gas on the body and lung tissues was calculated. CR-39 trace detector technology was used to accomplish this work. It was found that the Fakka fields contain a high concentration of radium, the main cause of radon, while it was lower in the Bazargan fields. In all samples, the concentration of radium (226Rn) and the radon gas released from it was much higher than the permissible dose level recommended by the International Commission on Radiological Protection. [ABSTRACT FROM AUTHOR]

This study focuses on investigating the release and dispersion of radon in diverse samples obtained from four designated sites (Rajpur, Maldevta, Kalsi and Dugadda) situated within the Main Boundary Thrust region of Garhwal Himalaya, Uttarakhand, India. In the Current research, we measured different radioactive parameters; including natural radioactivity (Radium content) and Mass exhalation rate. Using these measurements, we calculated the radon emanation fractions in 82 samples from four sampling sites. The radium content exhibited a range of 39 ± 8 Bq kg−1 to 442 ± 50 Bq kg−1, averaging at 88.2 ± 62.2 Bq kg−1. The Radon Exhalation rate displayed a range of 8.56 ± 3.1 mBq kg−1 h−1 to 144.9 ± 12.5 mBq kg−1 h−1 with an average rate of 48.4 ± 29.2 mBq kg−1 h−1. The variation in radon emanation fraction ranged from 0.62 to 8.52, with an average of 3.25 ± 1.60. Initially, the samples were categorized into rock and soil groups. To introduce an additional dimension, a secondary classification based on dry and wet conditions were subsequently incorporated. An increase in radon emanation fraction was observed for the wet samples due to higher moisture content. [ABSTRACT FROM AUTHOR]

The study assessed natural radioactivity in Rohtak and Jind districts, Haryana, India. Concentrations of radionuclides in soil and building materials were measured using gamma-ray spectroscopy. The "Canister Technique" was employed to estimate radon mass exhalation and surface exhalation rates. Results showed low radiation doses from soil radioactivity, with activity concentrations ranging from 3.7 to 51.7 Bq/kg for radium, 7.3 to 96 Bq/kg for thorium, and 52.2 to 585 Bq/kg for potassium. The findings also calculated radium equivalent activity, annual effective dose rate, hazard indices, and excess life time cancer risk. This research highlights the importance of understanding natural radioactivity for assessing environmental radiation exposure. [ABSTRACT FROM AUTHOR]

Radium‐226(226Ra) and barium (Ba) exhibit similar chemical behaviors and distributions in the marine environment, serving as valuable tracers of water masses, ocean mixing, and productivity. Despite their similar distributions, these elements originate from distinct sources and undergo disparate biogeochemical cycles, which might complicate the use of these tracers. In this study, we investigate these processes by analyzing a full‐depth ocean section of 226Ra activities (T1/2 = 1,600 years) and barium concentrations obtained from samples collected along the US GEOTRACES GP15 Pacific Meridional Transect during September–November 2018, spanning from Alaska to Tahiti. We find that surface waters possess low levels of 226Ra and Ba due to export of sinking particulates, surpassing inputs from the continental margins. In contrast, deep waters have higher 226Ra activities and Ba concentrations due to inputs from particle regeneration and sedimentary sources, with 226Ra inputs primarily resulting from the decay of 230Th in sediments. Further, dissolved 226Ra and Ba exhibit a strong correlation along the GP15 section. To elucidate the drivers of the correlation, we used a water mass analysis, enabling us to quantify the influence of water mass mixing relative to non‐conservative processes. While a significant fraction of each element's distribution can be explained by conservative mixing, a considerable fraction cannot. The balance is driven using non‐conservative processes, such as sedimentary, rivers, or hydrothermal inputs, uptake and export by particles, and particle remineralization. Our study demonstrates the utility of 226Ra and Ba as valuable biogeochemical tracers for understanding ocean processes, while shedding light on conservative and myriad non‐conservative processes that shape their respective distributions. Key Points: Water mass analysis shows significant shallow deficits and deep excesses of dissolved 226Ra and Ba in the Pacific Ocean along the GP15Shallow deficits seem driven by BaSO4 precipitation, deep excesses reflect benthic inputs that are more significant for 226Ra than for BaBudgets suggest that regional barium fluxes nearly balance, and the Pacific is likely a significant source of radium‐226 to the global ocean [ABSTRACT FROM AUTHOR]

Abstract The international GEOTRACES program has been instrumental in demonstrating how marine sediments are a critical source of dissolved Fe to the world's oceans. Here, we present dissolved iron (dFe) from the GEOTRACES North Pacific GP15 section, which, alongside other sediment‐source tracers (including dissolved δ56Fe, Mn, 228Ra, and particulate Fe), allows for identification of the dFe provenance of three distinct dFe depth maxima at the Alaskan margin. Two of these (shelf and abyssal depths) are of local Alaskan sedimentary origin. The third, a mid‐depth dFe maximum with an absence of 228Ra, is an advected signal that, based on tracer data from Western Pacific GEOTRACES transects and circulation models, must be advected from sedimentary sources on the Asian margin, ∼5,000 km away. This study illustrates the importance of measuring diagnostic sedimentary tracers like radium when assigning local margins as sedimentary sources of marine trace metal budgets.

ObjectivesThis practice parameter was revised collaboratively by the American College of Radiology (ACR) and the American Radium Society (ARS). This practice parameter provides updated reference literature regarding both clinical-based conventional total body irradiation and evolving volumetric modulated total body irradiation.MethodsThis practice parameter was developed according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website ( https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards ) by the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ARS.ResultsThis practice parameter provides a comprehensive update to the reference literature regarding conventional total body irradiation and modulated total body irradiation. Dependence on dose rate remains an active area of ongoing investigation in both the conventional setting (where instantaneous dose rate can be varied) and in more modern rotational techniques, in which average dose rate is the relevant variable. The role of imaging during patient setup and the role of inhomogeneity corrections due to computer-based treatment planning systems are included as evolving areas of clinical interest notably surrounding the overall dose inhomogeneity. There is increasing emphasis on the importance of evaluating mean lung dose as it relates to toxicity during high-dose total body irradiation regimens.ConclusionsThis practice parameter can be used as an effective tool in designing and evaluating a total body irradiation program that successfully incorporates the close interaction and coordination among the radiation oncologists, medical physicists, dosimetrists, nurses, and radiation therapists.

[Display omitted] Adsorption reactions of various cations on clay minerals have different effects on their environmental behaviors depending on the molecular-scale adsorption structure. Some cations form outer-sphere complexes via hydration, while others create inner-sphere complexes through dehydration. This preference dictates their environmental impact. However, the factors controlling these complex formations remain unclear. Furthermore, research on the adsorption preferences of radium (Ra) is lacking. Thus, this study conducted the first EXAFS study of Ra2+ adsorbed on clay minerals and showed that Ra2+ forms inner-sphere complexes on vermiculite, which can be surprising because Ra2+ is a divalent cation and prefers to be hydrated. In order to investigate the factors controlling the complex formations, this study conducted systematic EXAFS measurements and DFT calculations for alkali and alkaline earth metal cations. The results showed the importance of the size-matching effect between the adsorbed cation and the cavity of the tetrahedral sheets and that the complex formation can be estimated by the combination of the ionic radius and hydration enthalpy of the adsorbed cation. Furthermore, this study also analyzed environmental core samples. Their results showed the fixation of Ra2+ by clay minerals and the controlling factors can effectively predict cation environmental behavior. [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 present study aims to assess the accumulation of radon gas in the indoor environment of a test village in Tehri Garhwal, India. Radon gas accumulation was estimated from the radon exhalation rate, radium content in the soil, and radon concentration in indoor air. The measured and estimated radon concentrations in the indoor environment were observed to vary from 31 ± 25 to 177 ± 56 Bq/m3 (arithmetic mean = 69 Bq/m3) and 48 to 272 Bq/m3 (arithmetic mean = 108 Bq/m3), respectively. The results of this study may be helpful in understanding the behaviour of radon transport and its accumulation in enclosed spaces. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the activity concentrations of 226Ra, 232Th and 40K in the sand samples and the health hazards associated with them utilizing a NaI (Tl) gamma spectrometer. The average activity concentrations of 226Ra, 232Th and 40K were found to be 24.8 ± 10.1, 39.8 ± 16.4 and 531.3 ± 52.8 Bq kg−1, respectively. The calculated radiological hazard parameters, including radium equivalent activity, absorbed gamma dose and effective dose rate, were found to be 122.7 ± 34.0 Bq kg−1, 57.7 ± 14.9 nGy h−1 and 0.3 ± 0.1 mSv y−1, respectively. Notably, these results were observed to be below the recommended thresholds. Other measured hazard indices were also lower than the prescribed values. From a radiological perspective, the present study concludes that the sand samples do not pose any threat to human health when utilized as a building material. [ABSTRACT FROM AUTHOR]

Importance: Innovative nuclear medicine services offer substantial clinical value to patients. However, these advancements often come with high costs. Traditional payment strategies do not incentivize medical institutes to provide new services nor determine the fair price for payers. A shift towards a value-based pricing strategy is imperative to address these challenges. Such a strategy would reconcile the cost of innovation with incentives, foster transparent allocation of healthcare resources, and expedite the accessibility of essential medical services. Objective: This study aims to develop and present a comprehensive, value-based pricing model for new nuclear medicine services, illustrated explicitly through a case study of the radium [223Ra] treatment for bone metastases. In constructing the pricing model, we have considered three primary value determinants: the cost of the new service, associated service risk, and the difficulty of the service provision. Our research can help healthcare leaders design an evidence-based Fee-For-Service (FFS) payment reference pricing with nuclear medicine services and price adjustments. Design, setting and participants: This multi-center study was conducted from March 2021 to February 2022 (including consultation meetings) and employed both qualitative and quantitative methodologies. We organized focus group consultations with physicians from nuclear medicine departments in Beijing, Chongqing, Guangzhou, and Shanghai to standardize the treatment process for radium [223Ra] bone metastases. We used a specially designed 'Radium Nuclide [223Ra] Bone Metastasis Data Collection Form' to gather nationwide resource consumption data to extract information from local databases. Four interviews with groups of experts were conducted to determine the add-up ratio, based on service risk and difficulty. The study organized consultation meeting with key stakeholders, including policymakers, service providers, clinical researchers, and health economists, to finalize the pricing equation and the pricing result of radium [223Ra] bone metastases service. Main outcomes and measures: We developed and detailed a pricing equation tailored for innovative services in the nuclear medicine department, illustrating its application through a step-by-step guide. A standardized service process was established to ensure consistency and accuracy. Adhering to best practice guidelines for health cost data analysis, we emphasized the importance of cross-validation of data, where validated data demonstrated less variation. However, it required a more advanced health information system to manage and analyze the data inputs effectively. Results: The standardized service of radium [223Ra] bone metastases includes: pre-injection assessment, treatment plan, administration, post-administration monitoring, waste disposal and monitoring. The average duration for each stage is 104 min, 39 min, 25 min, 72 min and 56 min. A standardized monetary value for medical consumables is 54.94 yuan ($7.6), and the standardised monetary value (medical consumables cost plus human input) is 763.68 yuan ($109.9). Applying an agreed value add-up ratio of 1.065, the standardized value is 810.19 yuan ($116.9). Feedback from a consultation meeting with policymakers and health economics researchers indicates a consensus that the pricing equation developed was reasonable and well-grounded. Conclusion: This research is the first study in the field of nuclear medicine department pricing methodology. We introduce a comprehensive value-based nuclear medical service pricing method and use radium[223Ra] bone metastases treatment pricing in China as a case study. This study establishes a novel pricing framework and provides practical instructions on its implementation in a real-world healthcare setting. [ABSTRACT FROM AUTHOR]

Background: Prostate brachytherapy (BT) techniques have evolved over the past century. This paper aimed to preserve our collective memory of history and the early development of its technique. We searched articles in PubMed and Google Scholar using keywords referring to authors, dates, and BT technical details, including different radioactive sources and country-specific publications. We reviewed the work published by Holm and Aronowitz. The digital library Internet Archives was used to retrieve original journal articles, science newspaper printings, and government reports, which allowed us to situate the development of BT in its sociopolitical context in Europe and the USA. Our search was conducted in English, French, and German languages. Summary: Early BT methods were developed by European physicians with early access to radium. Technical advancements were made by HH Young, who brought this practice to the USA, where Barringer pioneered the use of radon seeds and low-dose interstitial brachytherapy. While centralized radiotherapy centers, such as Memorial Hospital in New York, emerged for training and research, the high cost of radium and opposing interests made brachytherapy harder to implement in Germany. After World War II, the introduction of man-made radioisotopes allowed experiments with colloidal solutions and new seeds, including I-125. In the 1980s, transrectal ultrasound allowed for more accurate radioactive seed insertion and replaced the transrectal finger guidance. [ABSTRACT FROM AUTHOR]

In this review, the online searchable research articles were scrutinized for the data presented in line with radioactivity and dose estimates from both terrestrial environments and foodstuffs from Bahi district and other parts of Tanzania. The data on natural gamma ray dose rates from Bahi localities were observed with variations among researchers. The observed ranges of radioactivity concentrations (Bq kg−1) in soil were 226Ra (28.5–57.4), 232Th (38.1–521.3), and 40K (562.9–665.0). Deep closed water wells with installed pumps from Ilindi and Bahi Mission reported radioactivity concentration of 238U 3.08 Bq L−1 and Ilindi swamps reported radioactivity concentrations of 226Ra 15.35 Bq L−1, whereas radioactivity concentrations of 238U in cereals were within the annual tolerable limits of 0.001–0.02 Bq kg−1. The quantity and accessibility of published studies, as well as the diversity of the data, point to the necessity for additional studies to be carried out in order to obtain comprehensive baseline data. [ABSTRACT FROM AUTHOR]

A study on natural radioactivity in soil around Tummalapalle uranium mineralised region was carried out. The aim of this study was to find the activity of primordial radionuclides 226Ra, 232Th and 40 K over the span of 5 years from 2018 to 2022 to understand the trend of activity of radionuclides in soil and impact of mining activities on the surrounding soil. The overall average activity of 226Ra, 232Th and 40 K over the years has been found to be 25 Bq/kg, 40 Bq/kg and 478 Bq/kg, respectively. The 226Ra and 232Th activities have been found to be less, whereas 40 K activity has been found to be slightly higher than the worldwide average of 32, 45 and 412 Bq/kg. The activity of radionuclides over the years does not show any increasing trend, which indicates that there is no impact of mining activities in the region on the soil in surrounding environment. Radium equivalent for soils was found to be 117.10 Bqkg−1, which is lower than the recommended limit of 370 Bqkg−1, and the annual effective external dose was found to be 345.56 µSvy−1, which is less than the worldwide average of 460 µSvy−1. External hazard index was found to be 0.35 Bq kg−1, which indicates insignificant radiation hazard from natural radionuclides in soil. [ABSTRACT FROM AUTHOR]

Targeted alpha therapy (TαT) represents an emerging and cutting-edge treatment option for patients dealing with highly challenging metastatic cancer diseases. Critically, the limited supply of alpha-particle-emitting radionuclides, so-called alpha in vivo nanogenerators, hampers wider utilization of TαT in clinical settings. This could effectively be circumvented by alternative production routes, including straightforward purification and reformulation strategies. Radionuclide generators offering great potential in simple and robust elution strategies can be provided that still adhere to high radioisotopic, radionuclidic, and radiochemical purity criteria. This study takes a first step towards novel separation strategies by providing additional sources of alpha in vivo nanogenerators for TαT through experiments with various metal surrogates. With different systems, 232Th/natBa was used as a radionuclide generator analogue to 227Th/223Ra, and 232Th/natBa/natLa was used as a triplet analogue to 229Th/225Ra/225Ac. Three selective resins (UTEVA, TEVA, DGA-N) were evaluated for the 232Th/natBa system. Two perturbations of the best-performing resin were further evaluated using a larger diameter column and 1 week of equilibration. For the 232Th/natBa/natLa separation system, a combined column with two selective resins (TK200, TK101) was employed and evaluated. The results thus obtained pave the way for alternative separation strategies in radioactive proof-of-concept validation in the near future.

BackgroundThe authors assessed the association between radon decay products (RDP) exposure and histologic types of incident lung cancer in a cohort of 16,752 (91.6% male) Eldorado uranium workers who were first employed from 1932 to 1980 and were followed through 1969-1999.MethodsSubstantially revised identifying information and RDP exposures were obtained on workers from the Port Radium and Beaverlodge uranium mines and from the Port Hope radium and uranium refinery and processing facility in Canada. Poisson regression was conducted using the National Research Council's Biological Effects of Ionizing Radiation (BEIR) VI-type models to estimate the risks of lung cancer by histologic type from RDP exposures and γ-ray doses.ResultsLung cancer incidence was significantly higher in workers compared with the general Canadian male population. Radiation risks of lung cancer for all histologic types (n = 594; 34% squamous cell, 16% small cell, 17% adenocarcinoma) increased with increasing RDP exposure, with no indication of curvature in the dose response (excess relative risk per 100 working level months = 0.61; 95% confidence interval, 0.39-0.91). Radiation risks did not differ by histologic type (p = .144). The best-fitting BEIR VI-type model included adjustments for the significant modifying effects of time since exposure, exposure rate, and attained age. The addition of γ-ray doses to the model with RDP exposures improved the model fit, but the risk estimates remained unchanged.ConclusionsThe first analysis of radiation risks of lung cancer histologic types in the Eldorado cohort supported the use of BEIR VI-type models to predict the future risk of histologic types of lung cancer from past and current RDP exposures.Lay summaryLung cancer survival depends strongly on the cell type of lung cancer. The best survival rates are for patients who have the adenocarcinoma type. This study included 16,752 Eldorado uranium workers who were exposed to radon and γ-ray radiation during 1932-1980, were alive in 1969, and were followed for the development of new lung cancer during 1969-1999. One third of all lung cancers were of the squamous cell type, whereas the adenocarcinoma and small cell types accounted for less than 20% each. Radiation risks of lung cancer among men increased significantly with increasing radon exposure for all cell types, with the highest risks estimated for small cell and squamous cell lung cancers.

NASA has encouraged studies on 226Ra deposition in the human brain to investigate the effects of exposure to alpha particles with high linear energy transfer, which could mimic some of the exposure astronauts face during space travel. However, this approach was criticized, noting that radium is a bone-seeker and accumulates in the skull, which means that the radiation dose from alpha particles emitted by 226Ra would be heavily concentrated in areas close to cranial bones rather than uniformly distributed throughout the brain. In the high background radiation areas of Ramsar, Iran, extremely high levels of 226Ra in soil contribute to a large proportion of the inhabitants' radiation exposure. A prospective study on Ramsar residents with a calcium-rich diet was conducted to improve the dose uniformity due to 226Ra throughout the cerebral and cerebellar parenchyma. The study found that exposure of the human brain to alpha particles did not significantly affect working memory but was significantly associated with increased reaction times. This finding is crucial because astronauts on deep space missions may face similar cognitive impairments due to exposure to high charge and energy particles. The current study was aimed to evaluate the validity of the terrestrial model using the Geant4 Monte Carlo toolkit to simulate the interactions of alpha particles and representative cosmic ray particles, acknowledging that these radiation types are only a subset of the complete space radiation environment.

Transfer factors (TFs) are widely used tools for assessing the uptake of radionuclides by plants. The literature contains numerous studies on TFs in tropical and temperate climates; however, the existing data on TFs in arid and semi-arid climates are very scarce. Furthermore, the current trend in nuclear energy expansion in countries with this type of climate necessitates knowledge of the mechanisms of radionuclide incorporation by plants as well as the TF values. For this reason, this work investigates the TFs of 238U and 226Ra in plants in a study area during the summer period under conditions equivalent to a semi-arid climate. The selected plants were Scolymus hispanicus L., Eryngium campestre L., Chenopodium vulvaria L., and Chenopodium album L., which were collected in the vicinity of a waste dump from an abandoned copper mine. The selected study area has radionuclide levels above the global average, in addition to heavy metals, as it is a waste dump from an abandoned copper mine. The range of transfer factors for 238U varied between 1.5 × 10−4 kg−1 kg−1 and 7.8 × 10−3 kg−1 kg−1, while for 226Ra, the range was between 1.8 × 10−4 kg−1 kg−1 and 4.0 × 10−2 kg−1 kg−1. The correlations found with PCA were (i) 238U with Fe and Al, and (ii) 226Ra with S, Ti, Ca, and Sr. A transfer model of 238U and 226Ra was created using multiple linear regression analysis. The model showed how 238U was related to the presence of Al, while 226Ra was related to Al, Fe, and Ti. The results obtained have allowed us to propose a model for the incorporation of 238U and 226Ra, taking into account the chemical composition of the soil. The results obtained indicate that both Scolymus hispanicus L. and Eryngium campestre L. could be utilized in phytoremediation for soils contaminated by natural radionuclides in semi-arid climates. The TFs, as well as the proposed model, allow us to expand the knowledge of the absorption of natural radionuclides by plants in regions with arid and semi-arid climates, which is necessary for the radiological risk assessment of future nuclear fuel cycle facilities.

Colorectal cancer (CRC) is the third most commonly occurring cancer in the United States, with higher incidence rates among Black populations. Groundwater concentrations of natural radionuclides uranium and radium have seldom been investigated in relation to CRC despite their known carcinogenicity. We investigate spatial patterns of CRC by race, and in relation to groundwater concentrations of uranium and radium, testing the hypothesis that uranium and radium in groundwater might differentially contribute to incident CRC in Black and White populations in counties of Georgia, USA. Black populations showed a higher incidence of CRC than White populations; the median incident rate difference was 9.23 cases per 100,000 (95% CI: 2.14, 19.40). Spatial cluster analysis showed high incidence clusters of CRC in similar regions for Black and White populations. Linear regression indicated there are, on average, 1–2 additional cases of colorectal cancer in counties with higher levels of radium in their groundwater, irrespective of race. Uranium was not associated with CRC. This ecologic study suggests that radium in groundwater may be linked with increased incidence of CRC, although it did not explain higher CRC incidence rates in Black populations. Further studies are needed to verify this association given the inherent limitations in the ecologic study design and the crude exposure assessment.

The distribution of 226Ra, 232Th, 40K, 210Po and 210Pb radionuclides in the illuviated soils of Somwarpet taluk, Coorg district of Karnataka state are investigated. In a vertical profile, soil samples were collected and the activity concentrations of these radionuclides were determined. The activity concentration of 210Po and 210Pb was determined using the radioanalytical method. The activity concentration of 226Ra, 232Th and 40K radionuclides in the lowest layer or the illuviated horizon of the vertical profile were found to be highest, due to accumulation of organic matter and clay. The average 210Po and 210Pb activity concentration is 12.49 Bq kg−1 and 33.94 Bq kg−1 in the top layer of the soil, 3.01 Bq kg−1 and 16.96 Bq kg−1 in the second layer, and 1.53 Bq kg−1 and 7.11 Bq kg−1 in the third layer respectively, which is high in the top surface of the soil. The determined physico-chemical parameters and the dependence of radionuclides were analysed using Pearson correlation analysis, which shows that insignificant associations could be attributable to changes in physico-chemical characteristics of soil in different sampling locations. [ABSTRACT FROM AUTHOR]

The features of the concentration distribution of 238U, 232Th, and 226Ra in the surface layer in the bottom sediments of the shelf and continental slope of Svalbard are considered. The content of 226Ra, 232Th, and 238U varied in the range 22–134.3, 22.4–50.9, and 10.9–37.7 Bq/kg, respectively. The amount of 226Ra nonequilibrium with 238U (226Raex) ranged from 23 to 73% of the total 226Ra content in sediments. The maximum concentrations of 226Ra, 238U, 232Th, and 226Raex (134.3, 37.7, 50.9, and 98.2 Bq/kg, respectively) were obtained in the area of increased bioproductivity (Eagle Trough). In this zone, the relationship between the concentrations of 226Ra and 226Raex with the content of organic matter in sediment is well expressed, the correlation coefficients are R = 0.94 and 0.92, respectively, which indicates a significant contribution of the biological community to the accumulation of 226Ra in bottom sediments. The 226Ra concentration and the 226Ra excess value are negatively related to the redox potential of the sediment (R = –0.88). This pattern is also true in other areas of the Svalbard waters. In general, for the entire array of observations, the concentrations of 238U and 232Th increase with increasing content of organic carbon in the sediment (R = 0.72 and 0.7, respectively). The concentrations of 238U and 232Th decrease with increasing Ccarb content in the sediment (R = –0.79 and –0.81, respectively). The data obtained indicate the need to take into account the 226Ra excess when assessing the total natural radioactivity of marine sediments, the value of which may exceed the radioactivity of 238U and 232Th. [ABSTRACT FROM AUTHOR]

To conduct an appropriate use criteria expert panel update on clinical topics relevant to current clinical practice regarding postmastectomy radiation therapy (PMRT). An analysis of the medical literature from peer-reviewed journals was conducted from May 4, 2010 to May 4, 2022 using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines to search the PubMed database to retrieve a comprehensive set of relevant articles. A well-established methodology (modified Delphi) was used by the expert panel to rate the appropriate use of procedures. Evidence for key questions in PMRT regarding benefit in special populations and technical considerations for delivery was examined and described. Risk factors for local-regional recurrence in patients with intermediate-risk disease that indicate benefit of PMRT include molecular subtype, age, clinical stage, and pathologic response to neoadjuvant chemotherapy. Use of hypofractionated radiation in PMRT has been examined in several recent randomized trials and is under investigation for patients with breast reconstruction. The use of bolus varies significantly by practice region and has limited evidence for routine use. Adverse effects occurred with both PMRT preimplant and postimplant exchange in 2-staged breast reconstruction. Most patients with even limited nodal involvement will likely benefit from PMRT with significant reduction in local-regional recurrence and potential survival. Patients with initial clinical stage III disease and/or any residual disease after neoadjuvant chemotherapy should be strongly considered for PMRT. Growing evidence supports the use of hypofractionated radiation for PMRT with equivalent efficacy and decreased acute side effects, but additional evidence is needed for special populations. There is limited evidence to support routine use of bolus in all patients. Timing of PMRT regarding completion of 2-staged breast reconstruction requires a discussion of increased risks with radiation postimplant exchange compared with increased risk of failure of reconstruction or surgical complications with radiation preimplant exchange. [ABSTRACT FROM AUTHOR]

Objectives: To investigate whether baseline 18F-sodium fluoride (NaF) and 18F-choline PET activity is associated with metastatic castration-resistant prostate cancer (mCRPC) global and individual bone metastases' DWI MR imaging response to radium-223 treatment. Methods: Thirty-six bone-only mCRPC patients were prospectively recruited from three centers. Whole-body (WB)-MRI with DWI and 18F-NaF and 18F-choline PET/CT were performed at therapy baseline and 8-week intervals. In each patient, bone disease median global (g)ADC change between baseline and follow-up was calculated. Additionally, up to five bone target lesions per patient were delineated and individual median ADC change recorded. An ADC increase > 30% defined response per-patient and per-lesion. For the same targets, baseline 18F-NaF and 18F-choline PET SUVmax were recorded. Mean SUVmax across patient targets was correlated with gADC change and lesion SUVmax with per-lesion ADC change. Results: A total of 133 lesions in 36 patients (14 responders) were analyzed. 18F-NaF PET per-patient mean SUVmax was significantly higher in responders (median = 56.0 versus 38.7 in non-responders; p = 0.008), with positive correlation between SUVmax and gADC increase (rho = 0.42; p = 0.015). A 48.7 SUVmax threshold identified responders with 77% sensitivity and 75% specificity. Baseline 18F-NaF PET per-lesion SUVmax was higher in responding metastases (median = 51.6 versus 31.8 in non-responding metastases; p = 0.001), with positive correlation between baseline lesion SUVmax and ADC increase (rho = 0.39; p < 0.001). A 36.8 SUVmax threshold yielded 72% sensitivity and 63% specificity. No significant association was found between baseline 18F-choline PET SUVmax and ADC response on a per-patient (p = 0.164) or per-lesion basis (p = 0.921). Conclusion: 18F-NaF PET baseline SUVmax of target mCRPC bone disease showed significant association with response to radium-223 defined by ADC change. Clinical relevance statement: 18F-sodium fluoride PET/CT baseline maximum SUV of castration-resistant prostate cancer bone metastases could be used as a predictive biomarker for response to radium-223 therapy. Key Points: • 18F-sodium fluoride PET baseline SUVmax of castration-resistant prostate cancer bone metastases showed significant association with response to radium-223. • Baseline 18F-sodium fluoride PET can improve patient selection for radium-223 therapy. • Change in whole-body DWI parameters can be used for response correlation with baseline 18F-sodium fluoride PET SUVmax in castration-resistant prostate cancer bone metastases. [ABSTRACT FROM AUTHOR]

Over the past century, human activities have contributed to the release of 226Ra (t½ = 1,600 y) in the environment, increasing the potential risks for human exposure and thus prompting scientists to monitor it. Inductively coupled plasma mass spectrometry (ICP‐MS) is an alternative to alpha‐spectrometry for the quantification of 226Ra. However, the performances of radioanalytical procedures are rarely compared in a rigorous framework, which means that researchers may choose one on subjective factors or guesses. This article compares five published methods for the separation and preconcentration of 226Ra in drinking waters based on chromatographic and extraction resins prior to its analysis by ICP‐MS. We evaluated the turnaround time, generated wastes, and final cost of each protocol as the economic aspect can be an important criterion when selecting a method, particularly for sustainable environmental monitoring. Our results showed that 226Ra was successfully separated and preconcentrated, yielding recoveries ranging between 84% and 105%. Method detection and quantification limits of respectively 2–7 fg L−1 (0.1–0.3 mBq L−1) and 6–24 fg L−1 (0.2–0.9 mBq L−1) were achieved when the separation method was coupled with ICP‐MS. The turnaround times ranged between 6 and 21 hours, whereas the cost of the methods varied between 40 and 132 USD. This study highlights for the first time that methodologies recently published on the evaluation of 226Ra levels in drinking water by ICP‐MS have comparable figures of merit. Our results offer essential insights into the selection of the most suitable separation method. [ABSTRACT FROM AUTHOR]

NASA has encouraged studies on 226Ra deposition in the human brain to investigate the effects of exposure to alpha particles with high linear energy transfer, which could mimic some of the exposure astronauts face during space travel. However, this approach was criticized, noting that radium is a bone-seeker and accumulates in the skull, which means that the radiation dose from alpha particles emitted by 226Ra would be heavily concentrated in areas close to cranial bones rather than uniformly distributed throughout the brain. In the high background radiation areas of Ramsar, Iran, extremely high levels of 226Ra in soil contribute to a large proportion of the inhabitants' radiation exposure. A prospective study on Ramsar residents with a calcium-rich diet was conducted to improve the dose uniformity due to 226Ra throughout the cerebral and cerebellar parenchyma. The study found that exposure of the human brain to alpha particles did not significantly affect working memory but was significantly associated with increased reaction times. This finding is crucial because astronauts on deep space missions may face similar cognitive impairments due to exposure to high charge and energy particles. The current study was aimed to evaluate the validity of the terrestrial model using the Geant4 Monte Carlo toolkit to simulate the interactions of alpha particles and representative cosmic ray particles, acknowledging that these radiation types are only a subset of the complete space radiation environment. [ABSTRACT FROM AUTHOR]

In this work, closed can technique is used to estimate the radon and radium content in solid samples collected from Ktebban River, north Basrah City. The radon concentration in the studied solid samples was between 9.46±2.29 Bq.m-3 to 29.83±4.81 Bq.m-3, so that the effective radium variation could be about 0.001 Bq.kg-1 to 0.004571 Bq.kg-1 since it was responsible for radon emanation in the air. These values considered as acceptable values when comparing worldwide and neighbors countries. The flux and exhalation per unit area and per unit mass arranged between 0.13Bq m-2 h-1 to 0.54Bq m-2 h-1 and 0.003Bq m-2 h-1 to 0.015Bq m-2 h-1, respectively. These values are also lower than the reported worldwide limit. This could suggest that it is likely safe to use such sediments for building materials and other uses. [ABSTRACT FROM AUTHOR]

Forty soil samples from district Palwal of Southern Haryana, India were collected to estimates the radon/thoron exhalation rate using scintillation detector-based SMART RnDuo out of which twenty samples were tested to estimate the activity of 226Ra, 232Th and 40K using high purity germanium (HPGe) gamma-ray spectrometry. The radon mass exhalation rate (mBqkg−1h−1) was observed as {range (mean)} {16 ± 1–48 ± 3 (28 ± 8)} and thoron surface exhalation rate (Bqm−2h−1) was observed as {1800 ± 198–6331 ± 205 (3850 ± 850)}. Activities of radium (226Ra), thorium (232Th) and potassium (40K) were {range (mean)} observed as {28.4–48.4 (40.0 ± 1.4)}, {49.7–75.0 (62.7 ± 1.6)} and {432–698 (522.9 ± 17.6)}, respectively. It is observed that the radium in 75% samples while thorium and potassium in all samples were found to higher than the world's average values of 35, 30 and 400 Bqkg−1, respectively, as reported by UNSCEAR. Average of radon mass exhalation and thoron surface exhalation rates exceeded the world's mean value 57 mBq kg−1 h−1 and 3600 Bq m−2 h−1, respectively. Health hazard index is well below the unity (< 1), which indicates that there are no gamma radiation hazards associated with samples collected from the study region. [ABSTRACT FROM AUTHOR]