226Ra Concentrations Research Articles

Elevated Plasma IL-6 Coincides with Activation of STAT3 in PBMC After Acute Resistance Exercise.

Changes in plasma concentrations of anti-inflammatory cytokines, such as interleukin-6 (IL-6) and IL-10, after acute resistance exercise (RE) have been widely explored. Whether observed changes in plasma cytokine concentration correspond to the activation of anti-inflammatory signaling pathways in immune cells after acute RE is unknown. This study aimed to determine if changes in plasma cytokines after acute RE resulted in the activation of anti-inflammatory signaling pathways in peripheral blood mononuclear cells (PBMC). Healthy young males (N = 16; age = 23.5 ± 2.7 yr; BMI = 22.4 ± 1.7 kg·m-2) participated in a single session of whole-body RE (4 sets of 4 different exercises at 70% 1-repetition maximum with the last set to failure) and a sedentary control (CON) condition in a randomized crossover design. Blood samples were collected at several time points before and after the exercise bout. Higher plasma IL-6, IL-10, and IL-1 RA concentrations were observed after RE compared with CON. Phosphorylation of STAT3 and protein expression of SOCS3 in PBMC were increased in RE compared with CON. The elevation of plasma IL-6, but not IL-10, coincided with the activation of STAT3 signaling in PBMC. These results highlight a potential mechanism by which RE may exert anti-inflammatory actions in circulating immune cells.

The Effect of Heating Rate on the Microstructure Evolution and Hardness of Heterogeneous Manganese Steel

The use of a rapid heating method to achieve heterogeneity of Mn in medium-manganese steel and improve its comprehensive performance has been widely studied and these techniques have been widely applied. However, the heating rate (from α to γ) has not received sufficient attention with respect to its microstructure-evolution mechanism. In this study, the effect of heating rate on the microstructure evolution and hardness of heterogeneous medium-manganese steel was investigated by using X-ray diffraction (XRD), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) and DICTRA simulation. The results showed that the Mn distribution was heterogeneous in the initial microstructure of pearlite due to strong partitioning of Mn between ferrite and cementite. At low heating rates (<10 °C/s), the heterogeneity of Mn distribution was diminished to some extent due to the long-distance diffusion of Mn in high-temperature austenite. Contrastingly, at high heating rates, the initial heterogeneity of the Mn element could be largely preserved due to insufficient diffusion of Mn, which resulted in more ghost pearlite (GP: pearlite-like microstructure with film martensite/RA). Moreover, the high heating rate not only refines the prior austenite grain but also increases the total RA content, which is mainly composed of additional film RA. As the heating rate increases, the hardness gradually increases from 628.1 HV to 663.3 HV, due to grain refinement and increased dislocation density. Dynamic simulations have also demonstrated a strong correlation between this interesting microstructure and the non-equilibrium diffusion of Mn.

Assessment of natural radioactivity in the Higher and Tethys Himalayan Rocks along Manali-Leh Highway, India.

The Higher and Tethys Himalayan region of NW-Himalaya is less explored from the natural radioactivity mapping assessment, though geologically and tectonically, this region is still active. The concentration of primordial radionuclides (226Ra, 232Th, and 40K) in rock samples of the Manali-Leh Highway region of the Himalayas is determined in the present study using the HPGe detector. The radiological hazard parameters are also estimated in terms of radium equivalent activity (Raeq), annual effective dose (Ein and Eout), hazard indices (Hin, Hex, Hα, and Hγ), and gamma absorbed dose rate. SEM-EDS analysis was used to understand the mineralogical composition of the rocks. The activity concentration of 226Ra, 232Th, and 40K radionuclides varies from 1.4 ± 0.9 to 25.3 ± 1.2, 0.7 ± 0.5 to 59.6 ± 1.6, and BDL (below detection limit) to 830.3 ± 45.7Bqkg-1, with an average value of 13.0 ± 1.0, 21.7 ± 1.0, and 243.7 ± 25.2Bqkg-1, respectively. The average of Raeq in the study region lies within the safe limit of 370Bqkg-1. The hazard indices have values < 1, indicating no radiological hazards to the population from the rocks. The annual effective dose also has values less than the global average value. This study revealed that the rocks of the Higher Himalayan region have a higher concentration of natural radioactivity, while the Tethys Himalayan rocks have lower concentrations of 226Ra, 232Th, and 40K radionuclides. The origin of rocks from different lithologies may be the reason for the natural radioactivity variation. The average concentrations of primordial radionuclides in the region are within the world average indicating that the rocks of the region are safe to be used for different purposes.

Assessment of natural radioactivity levels in rice samples and their implications for radiological protection

ABSTRACT This study investigates the levels of natural and artificial radioactivity in rice samples collected from various local markets in Islamabad, Pakistan. The 226Ra, 232Th, and 40K activity concentrations were measured through gamma-ray spectrometry with a NaI(Tl) detector. The average activity concentrations were 1.67 ± 1.19 Bq kg−1 for 226Ra, 3.31 ± 1.83 Bq kg−1 for 232Th, and 88.51 ± 11.65 Bq kg−1 for 40K. Calculated radium equivalent (Raeq) values ranged from 7.35 to 18.08 Bq kg−1, with a mean value of 11.11 Bq kg−1, all below the permissible maximum of 370 Bq kg−1. The absorbed dose rates ranged from 6.85 to 16.39 nGy h−1, with an average of 10.64 nGy h−1, falling below the acceptable limit of 51 nGy h−1. The outdoor and indoor radiation hazard indices (Hex and Hin) had mean values of 0.03, both below the threshold value of one. The external and internal hazard indices (Iγ and Iα ) were both 0.088, also below the critical value of one. The excess lifetime cancer risk (ELCR) ranged from 0.28 to 0.11, with a mean value of 0.18, which is less than the critical value of one. Overall, the radioactivity levels in the analyzed rice samples are within the acceptable limits set by the International Commission on Radiological Protection and are below global averages. These results offer important insights into the radiological safety of rice consumption in the study area.

Natural radioactivity and technological properties of kaolinized granite from the Motajica mine, Bosnia and Herzegovina

For the production of ceramic tiles, it is necessary to use high-quality and economical raw materials, which will optimize the properties of the final product and meet the prescribed standards. For this reason, it is necessary to examine the properties of each potential raw material. This paper examines radioactivity and technological properties of kaolinized granite from the Motajica mine, in Bosnia and Herzegovina. Chemical analysis, X-ray diffraction (XRD), and thermal analysis (DTA) were carried out. In order to examine the technological (ceramic) properties of this raw material, ignition tests of the composite obtained by introducing kaolinized granite (with a content of 25 %) into the standard factory series of ceramic tiles were conducted at four selected temperatures (1050, 1100, 1120, and 1150 ℃). Total linear shrinkage, flexural strength, and water absorption were determined for the produced biscuit. Using gamma spectrometry, the activity concentrations of radionuclides 226Ra, 232Th and, 40K were measured, and then the radiation risk for external exposure of workers in the industry was assessed using hazard indices and doses. The radiation risk from the use of manufactured unglazed ceramic tiles in houses was also assessed. Statistical analysis of radionuclides for 100 samples of kaolinized granite was performed using descriptive statistics and hierarchical cluster analysis (HCA). It was observed that the average values of 226Ra, 232Th, and 40K are above the average for building materials in the world and amount respectively to 122 Bq kg−1, 96 Bq kg−1, and 1068 Bq kg−1. All other obtained values indicate that it is a quality raw material that, despite having an increased content of radioactive elements compared to the world average, does not represent a radiological hazard for workers and people who stay indoors on an annual basis. The tested raw material satisfies all technological criteria for further use and can be considered a desirable ingredient of ceramic composites because it can partially or completely replace feldspar.

Determination of natural radioactivity levels in soil samples from irrigated vegetable farming land in and around Addis Ababa, Ethiopia.

Soil samples were collected from vegetable agricultural areas in and around Addis Ababa, and their levels of radioactivity were measured. Gamma spectrometry with high-purity germanium detector was used to quantify radioactivity level. The average concentration of 226Ra, 232Th, and 40K were 32.8±2.1, 62.4±4.4, and 544.3±23.3Bqkg-1 respectively. The mean values of 232Th and 40K are higher, whereas the value of 226Ra is comparable with world average values. Radiological hazard indices, including radium equivalent activity (Raeq), absorbed dose rate (Dr), outdoor annual effective dose equivalent (Deff), external hazard index (Hex), internal hazard index (Hin), and gamma radiation representative level index (Iγ), were calculated based on the activity concentration of 226Ra, 232Th and 40K. The mean values were 163.9Bqkg-1, 78.7 nGy h-1, 0.10mSv y-1, 0.44, 0.53, and 0.60 respectively. All indices are lower than global recommended limit values. These results revealed that radiation hazard due to radionuclides in the soil of the study area is insignificant.

Activity Concentration of Natural Radionuclides in Surface Sediments of Major River Watersheds in Korea and Assessment of Radiological Hazards

The assessment of potential radiation hazards in accumulated sediments in aquatic ecosystems is vital for the management and disposal of sediments. Furthermore, preemptive management of radionuclides in terrestrial ecosystems is critical for marine ecosystem conservation. We analyzed the activity concentrations of natural radionuclides (226Ra,232Th, 238U, and 40K) in the surface sediments of major river watersheds in Korea and evaluated the radiation hazards stemming from these activity concentrations. The mean activity concentrations of 226Ra and 238U were lower than the global average, whereas those of 232Th and 40K were higher. The mean values of radium equivalent activity, external hazard index, and internal hazard index calculated from these activity concentrations did not exceed the recommended maximum values. The mean values of absorbed gamma dose rate in air and annual outdoor effective dose rate (AEDRout) were higher than the global average by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) but remarkably lower than the recommended and background values by the International Commission on Radiological Protection (ICRP) and the Korea Institute of Nuclear Safety (KINS). The contribution of 40K and 232Th to the AEDRout mean value was predominant. In conclusion, the surface sediments of major river watersheds in Korea are associated with negligible radiation hazards. These findings provide fundamental data for the management and treatment of sediments in terrestrial and marine ecosystems.

Assessment of radiological contamination due to gold mining in soil and food crops of Babban Tsauni, Gwagwalada, Nigeria.

This work assessed the activity concentrations of 238U(226Ra), 232Th, and 40K and their associated radiological risks due to exposure to soil and consumption of food crops in Babban Tsauni artisanal gold mine, Gwagwalada, Nigeria, using the gamma spectrometry technique. The mean activity concentrations of 226Ra, 232Th, and 40K in the mine soil were 60.2±9.9, 161.4±16.2, and 664.6±138.2, while they were 46.4±4.9, 79.9±39.3, 266.4±185.4 for tubers and 46.9±15.7, 100.5±35.8, 311.4±132.7 (Bq/kg) for grains, respectively. The results reveal that the activity concentrations of radionuclides in all samples exceeded the recommended values set by United Nations Scientific Committee on the Effects of Atomic Radiation (33, 45, and 420 Bq/kg) except 40K, which fell within the acceptable limit in all food crop sample types. Estimated results for radiological hazard parameters, radium equivalent, annual effective dose due to ingestion, and excess life cancer risk were within safe limits, while the annual effective dose due to external gamma radiation in soil and annual gonadal equivalent dose were significantly high in all investigated samples; these call for constant radiological monitoring.

Assessment of Soil Radioactivity Associated with Risk and Correlation with Soil Properties near Maanshan Nuclear Power Plant, Taiwan

This study analyzes the concentration of radioactive material in the soil near the Maanshan nuclear power plant (NPP). Out of the thirty samples, only one sample was found to have 137Cs radioactivity measuring 2.58 Bq/kg. The activity concentrations were 77.2–517.7 Bq/kg, 3.9–31.6 Bq/Kg, and 5.3–39.1 Bq/kg, respectively, with mean values of 344.4 Bq/kg, 18.6 Bq/kg, and 26.5 Bq/kg for 40K, 226Ra, and 232Th, respectively. These levels are lower than the global average of soil activity concentrations. The activity concentrations varied, with the highest levels being 7–8 times greater than the lowest levels. Clay content had a positive correlation and sand content had a negative correlation with 40K, 226Ra, and 232Th activity concentrations. The activity concentrations followed a normal distribution for 40K, 226Ra, and 232Th. The activity ratios for 232Th/226Ra, 40K/232Th, and 40K/226Ra were 1.43 ± 0.22, 13.1 ± 1.9, and 18.8 ± 4.1, respectively, and ratios show light minerals in the soils. The average values for external hazard indices (Hex) and radium equivalent activity (Raeq) were 0.22 Bq/kg and 83.0 Bq/kg, respectively, both of which are below the recommended limit values of 1.0 Bq/kg and 370 Bq/kg, respectively. The outdoor absorbed dose rate (DRex) and annual effective dose equivalent (AEDex) were 39.0 nGy/h and 47.8 μSv/y, respectively, both of which are lower than the global soil average of 59 nGy/h and 70 μSv/y, respectively. These results indicate that local residents and tourists are not at significant risk of radiological hazards from the soil. The soil activity concentrations can serve as a baseline for continuous monitoring, even after the Maanshan NPP is decommissioned in 2025.

Radionuclides distribution in soils and radon level assessment in dwellings of Mungo and Nkam Divisions, Cameroon.

Radionuclide and radon levels have been investigated in soil samples and residential environments within the Mungo and Nkam Divisions of the Littoral Region. These analyses employed gamma spectrometry facilitated by a NaI (Tl) detector for soil samples, yielding average activity concentrations of 226Ra, 232Th, and 40K at 23.8, 72, and 105Bqkg-1, respectively. Various radiological parameters were calculated to evaluate radiological hazards. Additionally, the indoor radon concentrations were quantified utilizing the CR-39 solid-state nuclear track detector (Radtrack), revealing an average concentration of 25Bqm-3 and an associated inhalation dose of 0.66mSv y-1. Risk assessments for lung cancer attributable to indoor radon exposure incorporated models such as the Harley model. An observed moderate correlation between indoor radon levels and external 226Ra concentrations implies that radon intrusion indoors might be substantially influenced by the 226Ra present in the subjacent soil, considering the construction of residential structures directly upon these terrains.

Determination of a standard efficiency using the ISOCS uncertainty estimator for calculating the activity concentration of 226Ra, 232Th, and 40K in concrete

The Activity Concentration Index (ACI) requires knowledge of the activity concentrations of 226Ra, 232Th (212Pb), and 40K, typically determined through gamma spectrometry. The inherent heterogeneity of concrete makes the determination of gamma counting efficiency a complex problem. For this reason, this study employed the ISOCS Uncertainty Estimator (IUE), which allows for probabilistic calculations based on variations in parameters affecting counting efficiency, such as dimensions, density, and composition. The IUE enabled the estimation of a representative efficiency for a standard concrete configuration applicable to concrete specimens and samples from existing structures. The results obtained with the proposed efficiency for natural radionuclides of the uranium and thorium series, along with 40K, compared to the classical material grinding method, showed no significant differences in the mean and variance. The maximum differences observed when applying regression analysis were less than 16 %, thus validating the representative efficiency obtained with the IUE.

Radiation doses assessment and radon exhalation rate from the soils of Albyda area, Yemen

This work focuses on evaluating the potential health hazards posed by natural radionuclides in soil samples collected from 20 different sites in the Albyda area, Yemen. The activity concentrations of 226Ra, 232Th and 40K and radon exhalation rates in the soil samples were investigated. Alpha GUARD detector was used to estimate 222Rn concentration, while activity levels for natural radionuclides were measured by HPGe detector. The average values obtained for 226Ra, 232Th, and 40K were 27.60 ± 2.40 Bq/kg, 35.07 ± 2.45 Bq/kg, and 544.71 ± 48 Bq/kg, respectively, and for 222Rn concentrations were 135 ± 15 Bq/m3. Our findings show that the concentrations of radionuclides were within the limits of the world average established by UNSCEAR, except the concentrations of 40K, which was slightly higher than the world average (420 Bq/kg), while the average 222Rn concentration was lower than the ICRP reference level of 300 Bq/m3, and the average area exhalation rate 3.46 × 10−5 Bq m−2 s−1 was lower than the UNSCEAR world average of 0.016 Bq m−2 s−1. Therefore, the soil in this study does not pose any radiological hazard to the population due to the harmful effects of ionizing radiation. The results of the current study highlight the potential health hazard posed by radon and radioactivity levels in the soil samples from Albyda area, Yemen, which will help to increase awareness of the radiological hazard and the data could also be used as a reference for future research on radioactivity mapping in the study area.

Natural radionuclide and &lt;sup&gt;137&lt;/sup&gt;Cs activity concentration in soils of the Brazilian State of Sergipe and their correlation with environmental characteristics

Radionuclides occur naturally in the environment, exposing living organisms to ionizing radiation. In addition, human activities have introduced artificial radionuclides such as 137Cs, among others, into the environment. To better understand the occurrence and behaviour of radionuclides in soil, several countries have developed radiological studies and constructed maps. An effort has been made in Brazil to assess the radioactivity in the soils of the country. In this study, the activity concentrations of natural radionuclides 40K, 226Ra and 228Ra, and artificial 137Cs were determined in samples at a depth of 20 cm collected from the soils of the Brazilian State of Sergipe, in a regular grid of 25 km x 25 km. Samples were analysed by gamma-ray spectrometry with the use of hyperpure germanium detectors. The results were correlated with the type of soil, geology, and climate characteristics of the State. The median activity concentrations of 40K, 226Ra, and 228Ra were 210.4 Bq.kg-1, 12.33 Bq.kg-1, and 18.69 Bq.kg-1, respectively. The results are lower than those reported for soils from other Brazilian States in the same region. The activity concentration of 137Cs was lower than the minimum detectable activity. The activity concentration of 40K in young soils of the semi-arid region was higher than that found in most weathered soils of the rainy regions due to the very low pluviometry of the semi-arid area. Higher activity levels of 226Ra were found in Planosol and for 228Ra it was found in the weathered soils (Acrisol) of the coastal zone. Maps of the distribution of the studied radionuclides were designed. The median value of the outdoor absorbed dose rate in air (Dnat) calculated for the soils of the State of Sergipe is lower when compared with other Brazilian States and the UNSCEAR’s worldwide median value.

Highly efficient radium removal from mine wastewater with fly ash NaP1 zeolite

This study investigates the application of NaP1 zeolite, synthesized hydrothermally from F-class fly ash, for treating radium-contaminated mine water. The objective was to assess the efficiency of NaP1 zeolite in removing radium ions from real mine water samples. Three samples with high concentrations of 226Ra and 228Ra and total dissolved cation contents ranging from 48.9 to 89.0 g/L were treated using sequential batch and fixed bed experiments. The NaP1 zeolite demonstrated high treatment efficiency for radium-sulfate and radium-strontium water, with removal rates of 97 % and 82 % for the 1st liter, and 54 % for the 53th and 9th liters, respectively. However, for radium-barium water, the maximum treatment efficiency was 45 % for the 1st liter, dropping to 0 % after 4th liter. This decline was attributed to the competitive adsorption of barium ions, which reduced the radium removal efficiency more rapidly than in the other water types. An additional experiment with synthetic barium water confirmed that 10 g of NaP1 zeolite adsorbed 1 g of Ba from one liter of distilled water. These results highlight the potential of NaP1 zeolite for radium removal in certain contexts, although its efficiency may be hindered by the presence of competing ions such as barium.

Blending phosphogypsum to mitigate radionuclide leaching for sustainable road base applications

Production of phosphoric acid generates a calcium sulfate byproduct known as phosphogypsum (PG). PG is not considered a suitable standalone road base material because of concerns such as strength and presence of radionuclides. This paper investigates the latter, specifically the influence of blending PG with common alkaline road base aggregates – limerock (LR) and recycled concrete aggregate (RCA) – on radionuclide leaching. Radionuclide leaching from several PG sources was assessed for gross alpha, gross beta, uranium, and combined radium (226 + 228). Solution pH affected Ra226 mobility, with minimum concentrations exhibited at a pH in the range of 6 to 8. Mobile Ra226 concentrations in RCA blends decreased compared to original PG; Ra226 mobility initially increased at low LR replacements but decreased with increasing mass of LR (50 %–75 %). The data suggest an additional mechanism beyond pH alone impacted Ra226 mobility from the blends, possibly the binding or substitution of radium by elevated concentrations of Ba, Sr, or Ca. Blending with RCA resulted in radionuclide concentrations below respective drinking water thresholds, mitigating leaching concern from PG-RCA road base blends. PG-LR blends can meet regulatory limits when incorporating appropriate PG sources, providing an avenue for PG-amended road base materials. The blending approach reduced Ra226 mobility from PG-amended base, accommodating more PG use, serving as an alternative scenario to end-of-life stacking.

Radioactivity Levels, Spatial Distribution, and Radiological Risk Assessment of 226Ra, 228Ra, 40K, and 3H in Water Samples from Dhaka City and Savar, Bangladesh.

This investigation was conducted to measure the radioactivity levels of 226Ra, 228Ra, 40K, and 3H in the 13 most popular branded bottled mineral water (BMW), 12 groundwater sources consumed in Dhaka city, Bangladesh, and six water samples collected from the nuclear object site at Savar, adjacent to Dhaka. The activity of 3H was measured by using a liquid scintillation counter, and a gamma-ray spectrometer with an HPGe detector was used to measure the activity of other radionuclides. The average activity concentrations of 226Ra, 228Ra, 40K, and 3H in BMW samples and groundwater were found to be 1.81 ± 0.43, 1.74 ± 0.40, 43.08 ± 6.23, 2.42 ± 0.16, and 1.61 ± 0.51, 1.69 ± 0.45, 57.42 ± 3.16, and 3.02 ± 0.19 Bq/L, respectively. In addition, the activity concentrations of identified radionuclides in water samples collected from Savar were found to be 1.59 ± 0.43, 1.53 ± 0.50, 99.83 ± 3.05, and 2.95 ± 0.20 Bq/L. With the exception of 3H, the activity concentration and the annual effective dose of 40K, 226Ra, and 228Ra surpassed the acceptable thresholds of the WHO. The combined activity of radium (Rac) also exceeds the USEPA recommended maximum permissible limit of 0.185 Bq/L. The excess lifetime cancer risk results were below the permissible threshold of 10-3 for radiological risks. Groundwater was subjected to an AAS analysis for common metals (Na, Mg, and Ca) and heavy metals (Fe, Cr, Cu, and Pb). The results showed that the heavy metals were below the detection limit. Radionuclide contents in groundwater of Dhaka city were mapped spatially using a GIS technique. Statistical analyses such as one-way ANOVA, one sample t test, and Pearson's correlation analysis were also performed. According to Pearson's correlation analysis, 228Ra is mostly responsible for radiation risk in BMW and groundwater.

Pioneering study of radioactivity in soil near the Payra 1320 MW Thermal Power Plant, the largest coal-fired thermal power plant in Bangladesh

ABSTRACT Coal combustion increases atmospheric radioactivity, harming those live in the periphery of coal-fired thermal power plants (CFTPPs). A pioneering study has been performed using a high-purity germanium detector by analysing 30 soil samples collected from distances of 50, 600, 1200, and 3000 metres in the periphery of the largest 1320 MW CFTPP, Payra, Bangladesh. The activity concentrations of 226Ra, 232Th and 40K ranged from 19–32, 31–90, and 420–870 Bq/kg, respectively, with most of the samples show 232Th and 40K levels above global averages. Elevated levels of 232Th and 40K in soil around Payra thermal power plant stem from natural minerals, granitic rocks, ash disposal, coal combustion residues, and environmental factors. Radiological hazard indices, including dose rates and cancer risk, exceed global averages, indicating unsafe radiation exposure for coal miners and locals. These findings are crucial for planning coal-fired power plants and stress the need for municipal regulation of fly ash and health monitoring to mitigate risks for workers and residents.

Distribution features of &lt;sup&gt;238&lt;/sup&gt;U, &lt;sup&gt;232&lt;/sup&gt;Th and &lt;sup&gt;226&lt;/sup&gt;Ra in bottom sediments of the shelf and continental slope of Svalbard

The features of the distribution of concentrations of238U,232Th and226Ra in the surface layer of bottom sediments in the bottom sediments of the shelf and continental slope of Svalbard are considered. The content of226Ra,232Th, and238U varied in the range 22–134.3, 22.4–50.9, and 10.9–37.7 Bq/kg, respectively. The amount of226Ra nonequilibrium with238U (226Raex) ranged from 23 to 73% of the total226Ra content in sediments. The maximum concentrations of226Ra,238U,232Th and226Raex(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 of226Ra and226Raexwith the content of organic matter in sediment is well expressed, the correlation coefficients areR= 0.94 and 0.92, respectively, which indicates a significant contribution of the biological community to the accumulation of226Ra in bottom sediments. The226Ra concentration and the226Ra 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 of238U and232Th increase with increasing content of organic carbon in the sediment (R= 0.72 and 0.7, respectively). The concentrations of238U and232Th decrease with increasing Ccarbcontent in the sediment (R= –0.79 and –0.81, respectively). The data obtained indicate the need to take into account the226Ra excess when assessing the total natural radioactivity of marine sediments, the value of which may exceed the radioactivity of238U and232Th.

Determination of Excessive Lifetime Cancer Risk for Workers Exposed to Natural Radioactive Materials in Various Equipment in Oil and Gas Sector

In the oil and gas sector of Basrah, natural radioactive materials are accumulated in various equipment like wellheads, pumps, and separation vessels, often manifested as scales, sludge, and other forms of waste. Without proper preventive measures, these accumulations pose significant risks to workers, the public, and the environment. This study aims to assess the lifelong cancer risks associated with production processes and the handling of resultant waste, be it scale sediments, sludge, or soil. Sample collection across different regions was based on the evaluation of production and storage facilities. Using a high-purity germanium detector (HPGe), activity concentrations of 226Ra, 232Th, and 40K were measured. These concentrations were then used with standard equations to determine indoor effective dose rates. The regional-weighted (the lifetime risk of cancer is a measure of the cumulative risk of cancer over a specific age range and has a clear, intuitive appear) average of the lifetime excessive cancer risk was varied between (0.40 to 0.11 ×10-3) for ELCRoutdoor, (3.13 to 0.86 ×10-3) for ELCRindoor and (0.97 to 3 ×10-3) for ELCRtotal, significantly surpassing the global average value of (0.29x10-3). This disparity underscores the heightened risk posed by these activities, emphasizing the urgent need for enhanced safety measures and regulatory oversight to safeguard human health and the environment.

Characteristic parameters and radon exhalation rates of aerated concrete blocks

ObjectiveTo understand the characteristic parameters and radon exhalation rates of aerated concrete blocks. MethodsA total of 39 nationally inspected samples were measured. Their dry density was determined based on their mass and volumes, their porosities were measured on the principle of volumetric expansion, and their radium content was determined using a high-purity germanium (HPGe) detector for gamma-ray spectroscopy. Furthermore, their diffusion lengths were quantified by establishing a combined cumulative and diffusion chamber, and their radon exhalation rates were measured through closed-box testing using a continuous radon monitor. ResultsThe aerated concrete blocks exhibited dry densities ranging from 464 to 840 ​kg/m3 [average: (654.0 ​± ​82.5) kg/m3], open porosities from 67.1 ​% to 81.1 % [average: (74.3 ​± ​3.3) %, radium (226Ra) content from 12.3 to 136 Bq/kg [average: (63.0 ​± ​30.4) Bq/kg], diffusion lengths from 0.49 to 1.01 ​m [average: (0.70 ​± ​0.15) m], and radon exhalation rates from 0.6 to 22.8 Bq·m−2·h−1 [average: (7.3 ​± ​5.3) Bq·m−2·h−1]. ConclusionAerated concrete blocks exhibit significantly higher porosities, diffusion lengths, and radon exhalation rates than traditional concrete and clay bricks. These blocks might contribute to the high indoor radon concentration observed in modern buildings in China.