Concentrations Of Th Research Articles

Internal dose rate due to intake of uranium and thorium by fish from a dam reservoir associated with a uranium mine in Brazil.

Uranium mining can cause environmental impacts on non-human biota around mine sites. Because of this, the reduction in non-human biota exposure becomes an important issue. Environmental radioprotection results from the evolution of human radioprotection; it is based on dose rate to non-human biota and uses, as a biological target, and has harmful effects on populations. In the present study, a flooded impoundment created following dam construction in a uranium mine plant undergoing decommissioning was investigated. Internal dose rates due to activity concentration of natural uranium (Unat) and 232Th in omnivorous, phytophagous, and carnivorous fish species were estimated. Radionuclide activity concentrations were obtained by spectrophotometry with arsenazo III in the visible range. The dose rate contribution of 232Th was lower than that of Unat. There were no differences between the internal dose rates to studied fish species due to 232Th, but there were differences for Unat. A dose rate of 2.30·10-2µGy∙d-1 was found due to the two studied radionuclides. Although this value falls below the benchmark for harmful effects, it is important to acknowledge that the assessment did not account for other critical radionuclides from uranium mining, which also contribute to the internal dose. Moreover, the study did not assess external doses. As a result, the possibility cannot be excluded that dose rates at the study area overcome the established benchmarks for harmful effects.

A preliminary study on determination of radioactivity levels and estimation of the annual effective dose in dried fruits consumed in Albania.

This work aimed to support Albania's food safety monitoring regime. In this context, the natural and artificial radioactivity was measured in 20 samples of dried fruits collected randomly in different markets of Tirana. The activity concentration of 40K, 226Ra, 232Th and 137Cs was determined by using the high-purity germanium detector. The maximum values of activity concentration in dried fruits were calculated as 517±22Bqkg-1 for 40K, 11.10±0.93Bqkg-1 for 226Ra, 4.38±0.26Bqkg-1 for 232Th and 0.83±0.14Bqkg-1 for 137Cs. The average values of activity concentration of 40K and 226Ra were 269and 6.05Bqkg-1 and the average effective dose to individuals from the intake of the dried fruits was 44μSv y-1. All average values in this study were lower than recommended values by reports United Nations Scientific Committee on the Effect of Atomic Radiation, World Health Organization and International Commission on Radiological Protection for all age groups. Therefore, all dried fruit samples in this study are safe for consumption with acceptable radiological risk and none of them pose any significant radiological impact. The obtained data in this paper and information for levels of radioactivity and ingestion absorbed dose from dried fruits can be used to be the basic data for future comparative analysis of the other studies.

Assessment of gamma absorbed doses and radiological risk indexes from soil radioactivity around the phosphate area in south Tunisia.

Human beings are constantly exposed to the radiations coming from the environment. This work assesses the radiological hazards of natural radioactivity in soil samples taken at four locations around the phosphate area in south Tunisia. Concentrations of primordial radionuclides were measured by gamma spectrometer using an HPGe detector. The overall mean values of 40K, 226Ra and 232Th concentrations were 264, 27 and 13Bqkg-1, respectively. From the radioactivity measurements, radiation hazard indices specified by the United Nation Scientific Committee on the Effect of Atomic Radiation such as radium equivalent activity (Raeq), absorbed dose rates ($ {\dot{\text D}} $) and annual effective dose (AED) to the population for outdoor environment were determined. The mean values for the abovementioned parameters were 64Bqkg-1, 33 nGy h-1 and 40μSv y-1, respectively.

Multiple growth of zirconolite in marble (Mogok metamorphic belt, Myanmar): evidence for episodes of fluid metasomatism and Zr–Ti–U mineralization in metacarbonate systems

Abstract. Fluid infiltration into (meta-)carbonate rocks is an important petrologic process that induces metamorphic decarbonation and potential mineralization of metals or nonmetals. The determination of the infiltration time and the compositional features of reactive fluids is essential to understand the mechanism and process of fluid–rock interactions. Zirconolite (ideal formula: CaZrTi2O7) is an important U-bearing accessory mineral that can develop in metasomatized metacarbonate rocks. In this study, we investigate the occurrence, texture, composition, and chronology of various types of zirconolite from fluid-infiltrated reaction zones in dolomite marbles from the Mogok metamorphic belt, Myanmar. Three types of zirconolite are recognized: (1) the first type (Zrl-I) coexists with metasomatic silicate and oxide minerals (forsterite, spinel, phlogopite) and has a homogeneous composition with high contents of UO2 (21.37 wt %–22.82 wt %) and ThO2 (0.84 wt %–1.99 wt %). (2) The second type (Zrl-II) has textural characteristics similar to those of Zrl-I. However, Zrl-II shows a core–rim zonation with a slightly higher UO2 content in the rims (average of 23.5 ± 0.4 wt % (n=8)) than the cores (average of 22.1 ± 0.3 wt % (n=8)). (3) The third type (Zrl-III) typically occurs as coronas around baddeleyite and coexists with polycrystalline quartz. Zrl-III has obviously lower contents of UO2 (0.88 wt %–5.3 wt %) than those of Zrl-I and Zrl-II. All types of zirconolite have relatively low rare earth element (REE) contents (< 480 µg g−1 for ΣREE). Microtextures and compositions of the three zirconolite types, in combination with in situ zirconolite U–Pb dating using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), reveal episodic fluid infiltration and element mobilization in the dolomite marbles. The first-stage infiltration occurred at ∼ 35 Ma, leading to the formation of Mg-rich silicates and oxides and accessory minerals (Zrl-I, baddeleyite, and geikielite). The reactive fluid was characterized by high contents of Zr, Ti, U, and Th. After that, some Zrl-I grains underwent a local fluid-assisted dissolution–precipitation process, which produced a core–rim zonation (i.e., the Zrl-II type). The final stage of fluid infiltration, recorded by the growth of Zrl-III after baddeleyite, took place at ∼ 19 Ma. The infiltrating fluid of this stage had relatively lower U contents and higher SiO2 activities than the first-stage infiltrating fluid. This study illustrates that zirconolite is a powerful mineral that can record repeated episodes (ranging from 35 to 19 Ma) of fluid influx, metasomatic reactions, and Zr–Ti–U mineralization in (meta-)carbonates. This mineral not only provides key information about the timing of fluid flow but also documents the chemical variation in reactive fluids. Thus, zirconolite is expected to play a more important role in characterizing the fluid–carbonate interaction, orogenic CO2 release, and the transfer and deposition of rare metals.

Environmental Radioactivity, Ecotoxicology (238U, 232Th and 40K) and Potentially Toxic Elements in Water and Sediments from North Africa Dams

The natural radioactivity of 238U, 232Th and 40K was measured in water and sediment samples collected from Sidi Salem dam (Tunisia) and Aïn Dalia dam (Algeria) in the Tuniso-Algerian transboundary basin. The samples were measured using a TERRA detector of gamma, beta, and alpha rays, and atomic absorption and gamma-ray spectrometry were used to analyze the levels of radionuclides and toxic elements, respectively. Potentially toxic elements (Fe, Pb, Zn, Ni, Cr, Cu and Cd) and associated health risks in surface water and sediment of dams were investigated in this present study. The concentrations of Fe, Pb, Zn, Ni, Cr, Cu and Cd in surface water ranged from 5.430 to 9.700 mg·L−1, 0.022 to 0.168, 0.018 to 0.142, 0.065 to 0.366, BDL to 0.0351, BDL to 0.071 and BDL to 0.048 mg·L−1, respectively. In the sediments, the concentrations of Fe, Pb, Zn, Cu, Ni, Cd and Cr were of the order of 136.7, 3.41, 3.22, 0.213, 0.182, 0.15 mg·L−1 and BDL, respectively. The mean radioactivity rates in the water samples were 1.72, 0.068 and 94.6 Bq·L−1 for 238U, 232Th and 40K, respectively (Tunisia dam), and were 1.9, 0.09 and 131.43 Bq·L−1 for 238U, 232Th and 40K, respectively (Algeria dam). The mean 238U, 232Th and 40K radioactivity concentrations measured in the sediment samples were 2.67, 0.18 and 197.87 Bq·kg−1, respectively (Tunisian dam), and were 4.34, 0.27 and 287.61 Bq·kg−1, respectively (Algeria dam). The activity concentration of 40K was higher than that of 238U and 232Th for the water and sediment samples. The activity concentrations follow the order 40K > 238U > 232Th. The cumulative impact of these radio-geochemical elements can cause immediate serious problems in the ecosystem due to their high potential toxicity to the environment and human health in this study area and can be transposable to any other similar region. A good knowledge of monitoring quality and quantity for transboundary water resources and international collaborations are essential to safeguard human health (women’s breast cancer, thyroid cancer, neurological impact) and avoid conflicts, especially during climatic upheavals of drought.

Fractionation of environmental radioactivity in road dust from a megacity: external and internal health risks.

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

Age-dependent annual effective dose and radiological health risk from salt and soil collected from Padag, Chaghi, Balochistan, Pakistan

ABSTRACT This study aimed to investigate the annual effective dose for different age groups and health hazards associated with natural radioactivity in salt and soil collected from Padag, Chaghi, Balochistan. All samples were analysed by using high-purity germanium (HPGe) and sodium iodide (NaI) detectors. The average values of concentration of 226Ra, 232Th and 40K in salt samples were found to be 10.49, 9.6 and 169.65 Bq.kg−1, respectively, using HPGe detector, while in case of NaI detector, these values were found to be 10.48, 9.89 and 161.73 Bq.kg−1, respectively. Similarly, the average values of concentration of 226Ra, 232Th and 40K in soil were found to be 24.59, 24.89 and 391.72 Bq.kg−1, respectively, using HPGe detector, while in case of NaI detector, these values were found to be 24.46, 24.71 and 358.31 Bq.kg−1, respectively. Significant correlations were found between the results obtained from HPGe and NaI detectors. The values of total annual effective dose due to ingestion of salt were found to be 2.46 × 10−5, 2.45 × 10−5, 3.55 × 10−5 and 1.13 × 10−5 μSv.y−1 using HPGe detector and 2.43 × 10−5, 2.44 × 10−5, 3.55 × 10−5 and 1.13 × 10−5 μSv.y−1 using NaI detector for the age groups (2–7 years), (7–12 years), (12–17 years) and (≥17 years), respectively. The highest value of annual effective dose was found in the age group 12–17 years and minimum was found in the age group ≥ 17 years. However, all values were found to be below the recommended value of 0.29 mSv. Total average radiological risk due to ingestion of salt for all age groups was found to be lower than the reported value.

Evaluation of Radioactivity Contents and Excess Lifetime Cancer Risk Due to Ingestion from Natural Radionuclides in Maize Samples from Some Selected Maize Farms in Ekiti State, Nigeria

The study was carried out to evaluate the radioactivity concentrations of 40K, 232Th and 238U in five maize samples collected from maize farms within Ekiti State, Nigeria. The activity concentration measurements were determined using n – type co-axial HPGe detectors for the state. The activity concentrations were found to vary from 994.67 – 2457.01 Bq Kg-1 for 40K, 32.84 – 91.88 Bq kg-1 for 232Th and 43.21 – 97.77 Bq kg-1 for 238U respectively. The annual effective dose to individuals from the consumption of the Maize was estimated on the basis of the measured radionuclides content in the food crop which ranged between 0.41 and 1.51 m Svy-1 respectively. The value1.04 m Svy-1 were obtained for the state as the mean total annual effective dose. The mean excess life time cancer risk was also calculated to be 2.06x10-9 . The value was compared with the internationally acceptable limits and found to be far less to the maximum permissible dose of 1.0 x10-3 recommended for the public by the United Nations Scientific Committee on the Effects of Atomic Radiation. Hence, the maize was found to be safe for human consumption.

Evaluation of Natural Radioactivity Level in Surface Soil from Bambasi District in Benishangul Gumuz Region, Ethiopia.

The study assessed the concentration of natural radionuclides in soil samples from the Bambasi district in Ethiopia's Benishangul Gumuz region using a gamma-ray spectrometer equipped with a high-purity germanium (HPGe) detector. The measured activity concentrations of 238U, 232Th, and 40K in soil samples varied from 46.2 ± 2.25 to 88.49 ± 5.73 Bq/kg, 73.4 ± 4.12 to 119.65 ± 8.45 Bq/kg, and 176.78 ± 8.63 to 396.71 ± 25.39 Bq/kg, respectively. The average concentration of 238U and 232Th exceeded the recommended worldwide population weighted average values of 32.0 and 45.0 Bq/kg, respectively, while the average concentration of 40K was below the recommended value of 420.0 Bq/kg. The mean absorbed dose rate was calculated to be 91.6 ± 5.1 nGy/h, which is above the recommended safe value of 59 nGy/h. The average annual effective dose equivalents for indoor and outdoor exposure were determined to be 2.65 ± 0.14 mSv/y and 0.66 ± 0.1 mSv/y, respectively. The calculated mean values of the internal hazard index, external hazard index, and gamma index across all soil samples were 0.72 ± 0.05, 0.55 ± 0.02, and 0.72 ± 0.02, respectively, all below the recommended safe threshold of one. These findings suggest that the activity concentrations observed in the soil samples exceed safe levels, indicating the necessity for further investigation into radioactivity levels and epidemiological studies regarding potential hazards from high background radiation.

Rare Earth Element Characteristics of Shales from Wufeng-Longmaxi Formations in Deep-Buried Areas of the Northern Sichuan Basin, Southern China: Implications for Provenance, Depositional Conditions, and Paleoclimate.

To explore the sedimentary environment and the background of the source area of organic-rich shales in the Wufeng-Longmaxi Formations in the northern Sichuan Basin, samples from Well XX1 in the area were subjected to geochemical testing and analysis of organic carbon content, trace elements, and rare earth elements (REEs). The results show that the total content of REE (ΣREE) of the shale in the Wufeng-Longmaxi Formations varied from 183.08 to 234.66 μg/g with an average of 212.59 μg/g, which is significantly higher than the content of the North American shale composite. The fluctuations in the total amount of REEs in the shale of the Wufeng-Longmaxi Formations reflect certain differences in the geochemical conditions of the Upper Ordovician-Lower Silurian shale. The ratios of LREE/HREE, LaN/YbN, LaN/SmN, and GdN/YbN and the distribution of normalized REE patterns indicate that the source supply or sedimentary structural background may have changed during the shale deposition period of the Wufeng Formation, while the shale deposition period of the Longmaxi Formation may be in a relatively stable source supply and sedimentary structural background. There is no significant correlation between δCe and ΣREE, and the obviously negative Eu abnormity and the weak Ce abnormity indicated that the diagenesis had a limited impact on REEs. Geochemical parameters such as values of ∑REE, δEu, δCe, Ceanom, and LaN/YbN indicate that the climate during the Wufeng-Longmaxi Formation shale deposition period was warm and humid, and the shale was deposited mainly in the suboxic-anoxic water environment. The deposition rate was stable and slow, providing good conditions for the production and preservation of organic matter. At the same time, this shows that the water environment of Wufeng Formation is more anoxic and reductive than that of Longmaxi Formation, which is more conducive to the preservation of organic matter. The correlation between ΣREE and the content of Sc, Ti, Cr, Co, Zr, Nb, Th, Hf, Ta, and other elements indicates that the sources of REEs in the shale of Wufeng and Longmaxi Formations in the study area are similar, mainly terrestrial clasts, and some may come from the sea. The REE distribution pattern shows that the shale provenance of the Wufeng-Longmaxi Formations mainly comes from the upper crust. The La/Yb-∑REE diagram shows that the sediment-parent rocks are mainly early sedimentary rocks and these sediment-parent rocks have granite provenance characteristics. Compared to La/Yb, LREE/HREE, LaN/YbN, and other REE characteristic parameters, it is inferred that the tectonic background of the study area is dominated by passive continental margin.

The content and distribution of natural (232Th, 238U, 40K) radionuclides in the model small lakes bottom sediments of different sedimentogenesis types (south of Western Siberia)

The assessment of the content and distribution of natural radionuclides (232Th, 238U, 40K) in stratified bottom sediments cores of the similar composition (silicon class) in model small lakes, taking into account the type of sedimentogenesis (humid, arid, and nival), in consistently changing landscape conditions of the south of Western Siberia, was carried out. In the bottom sediments of the model small lakes (silicon class) of the humid and arid sedimentogenesis type, the average content and distribution of Th, U and K are similar throughout the studied time interval (about 200 years). For bottom sediments in model lakes of the nival sedimentogenesis type, fluctuations in the average composition along the core, as well as generally higher Th and U contents, are observed.

Assessment of natural radioactivity in soil and olive mill pomace utilizing nal (TI) gamma-ray spectrometry and low background alpha/beta counting system

The study conducted in the northwest region of Jordan aimed to assess the levels of natural radioactivity in soil and olive mill pomace (OMP) samples. The researchers used Nal (TI) gamma-ray spectrometry to measure the activity concentrations of 226Ra, 232Th, 40K, and 137Cs in the samples. The average activity concentrations of 226Ra, 232Th, 40K, and 137Cs in the soil samples were found to be 18.624 ± 5.82, 12.276 ± 5.728, 518.33 ± 212.57, and 0.140 ± 0.09 (Bq,kg−1), respectively. In the OMP samples, the average activity concentrations of 226Ra, 232Th, and 40K were 7.272 ± 4.386, 3.454 ± 1.503, and 169.997 ± 81.873 (Bqkg−1), respectively, and no 137Cs was detected.The study also investigated fundamental parameters associated with radon, specifically the radon emanation coefficient (RnEC) and radon mass exhalation rate (Ex). The RnEC values ranged from 0.621 to 0.78 (Bqkg−1), with an average value of 0.71 ± 0.06 (Bqkg−1). The estimated Ex from the soil samples ranged from 65.83 to 124.86 (mBqkg−1h−1), with an average value of 99.74 ± 21.73 (mBqkg−1h−1).Regarding radiological hazards, the study examined various parameters, including radium equivalent activity, external and internal hazard indices, gamma and alpha indices, absorbed gamma dose rate, and excess lifetime cancer risk. All of these assessed values were found to be below the worldwide recommended limits for radiological safety.Additionally, the study analyzed the concentrations of gross alpha and gross beta radioactivities in soil and OMP samples. The soil samples had an average gross alpha activity of 4.642 ± 1.04 (Bqkg−1) and an average gross beta activity of 48.13 ± 14.50 (Bqkg−1). The OMP samples showed an average gross alpha activity of 0.32 ± 0.27 (Bqkg−1) and an average gross beta activity of 59.19 ± 12.94 (Bqkg−1).Overall, the obtained results are crucial for evaluating the radiological risks associated with natural radioactivity in the northwest region of Jordan. The findings establish baseline data for comparison and reference for radioactivity levels in the environment.

A Study on Determination of Natural Radionuclide Concentrations in Tap Water Samples Collected from the Districts of Sinop Province, Türkiye

Since Turkey's second nuclear power plant is planned to be built in Sinop province, it is very important to determine the background levels of radioactivity in this region. In the present study, activity concentrations of 226Ra, 232Th and 40K natural radionuclides in nine tap water samples collected from the districts of Sinop province located in the north of Turkey were determined using a high purity germanium detector (HPGe). The coordinates of sampling areas were also recorded by GPS device (Magellan Explorist 510). The mean activity concentrations of 226Ra, 232Th and 40K radionuclides in the studied waters were calculated to be 1.74 ± 0.49 Bq/L, 1.39 ± 0.35 Bq/L and 5.32 ± 1.41 Bq/L. In addition, annual effective dose equivalents from the intake of these radionuclides in the tap water samples were calculated for infants, children and adults and the found results were compared with the values recommended by international organizations. As a result, there is no risk in terms of natural radioactivity in the consumption of studied waters by humans.

Hydrochemical Characteristics of Groundwater in and around the Peenya Industrial Area in Bengaluru City

The present study aims to use the Water Quality Index (WQI) modeling method to know about groundwater hydrochemistry and drinking suitability in and around (5 km) the Peenya industrial area/estate in Bengaluru city. For this research study, 116 bore well samples were collected and examined for the pre (dry) and post (wet) monsoon seasons in 2021, following APHA standard procedures. According to the BIS standard, the TH, Ca, Mg, NO3, and TDS exceed the desirable limits in both seasons. The water quality examination data shows that TDS concentration is found to be higher above the desired limit (500 mg/l) during the pre- (63%) and post- (45%) monsoon seasons. Furthermore, 55% (pre-monsoon) and 15% (post-monsoon) of the groundwater samples exceed the BIS’s nitrate allowable limit (45 mg/l). Among the analyzed samples, the calcium content in 19% and 20% of samples exceeded the desirable limit (75 mg/l), and magnesium content in 87% and 83% exceeded the desirable limit (30 mg/l) in pre- and post-monsoon seasons. In 95% of samples, TH content exceeded the desirable limit (200 mg/l) in both pre- and post-monsoon seasons. Piper diagram plots were utilized to determine sources of dissolved constituents, rock-water interaction, and other factors that influenced the region’s groundwater composition. Based on hydro-chemical facies the Ca-Mg-HCO3 type of water predominates in the study area during pre (dry) and post (wet)-monsoon seasons of the year 2021. The chemistry of groundwater has deteriorated significantly because of several industrial and anthropogenic activities. The WQI spatial distribution map shows that groundwater quality has the greatest impact in the west and a few places in the north and south regions of the research area. This study was conducted in Bangalore’s Peenya industrial area to determine whether groundwater is suitable for drinking, identify the mechanisms governing groundwater’s geochemistry, and evaluate the effects of an industrial area on groundwater quality. The primary focus of this study is the major ion chemistry in this field.

MEASUREMENT OF NATURAL RADIOACTIVITY IN TAP WATER SAMPLES FOR SELECTED REGIONS IN ADEN GOVERNORATE, YEMEN

In the present work, we have measured specific activity concentrations of in eleven tap water samples for selected regions in Aden governorate by using high purity germanium detector (HPGe). The (HPGe) detector (CANBERA-model 7229N, USA) with an efficiency of 35% and energy resolution (2.6keV) at energy (1332.6keV) for 60Co, the high purity N-type semiconductor detector with physical characteristics of (geometry closed-end coaxial, (3×3 inch). The results have shown that, The highest value of specific activity concentration of 226Ra was found in in T7 Daar-Saad region which was equal to (0.525±0.29)Bq/L, while the lowest value of specific activity concentration of 226Ra was found in T11 Aden Assughra region which was equal to (0.017±0.006)Bq/L with an average value of (0.228±0.13)Bq/L. The highest value of specific activity concentration of 232Th was found in in T5 Khor-makser region which was equal to (0.319±0.18)Bq/L, while the lowest value of specific activity concentration of 232Th was found in T11 Aden Assughra region which was equal to (0.009±0.001)Bq/L with an average values of (0.129±0.089)Bq/L. The highest value of specific activity concentration of (40K) was found in in T2 (Al-Ma,allah) region which was equal to (0.4±0.26)Bq/L, while the lowest value of specific activity concentration of (40K) was found in T11 Aden Assughra region which was equal to (0.027±0.004)Bq/L with an average values of (0.141±0.021)Bq/L respectively. The annual ingestion effective dose (AED) ranged from (3.05 to 98.77μSv/y), (5.67 to 178.16μSv/y), and (3.41 to 119.08μSv/y), with average values of 42.65μSv/y, 78.62μSv/y and 48.62μSv/y, for infants, children and adults respectively. The excess lifetime cancer risk (ELCR) have been calculated, its values were lower than the world’s average value of (0.29×10−3) as reported by EPA. The overall annual effective dose and cancer risks corresponding to radionuclide intake in tap water were below the recommended maximum values. It was inferred from the findings of this study that the water used as the sample does not have any significant radiological impacts to human body and is safe to be used as drinking water.

Assessment of the radiological health risk from radionuclide presence and transfer factor from soil to corn in some selected non-oil producing riverine areas of Akwa Ibom state

The main objective of this study was to estimate the activity concentration (AC) of 238U, 232Th and 40K, assess the health risk information from radionuclides presence in the soil and corn and the transfer influence from soil to corn. The key device used for the analysis was a Sodium Iodide Thallium detector. 238U AC in soil ranges from 14.09±0.27 Bqkg-1 to 18.70±0.31 Bqkg-1 with mean value of 15.69±0.28 Bqkg-1; 238U AC in corn varies from 9.36±0.22 Bqkg-1 to 14.78±0.27 Bqkg-1 with mean value of 11.53±0.24 Bqkg-1. 232Th AC in soil is from 12.32±0.46 Bqkg-1 to 48.76±0.91 Bqkg-1 with mean value of 35.97±0.76 Bqkg-1. 232Th AC in corn ranges from 8.26±0.37 Bqkg-1 to 35.19±0.77 Bqkg-1 with average value of 17.86±0.53 Bqkg-1. 40K values from the soil samples varies from 313.61±6.81 Bqkg-1 to 472.63±8.36 Bqkg-1 with mean value of 384.672±7.52 Bqkg-1. 40K varies from 374.85±7.45 Bqkg-1 to 478.55±8.41 Bqkg-1 with average value of 425.51±7.93 Bqkg-1from corn samples. The mean transfer factor for 238U, 232Th and 40K was obtained as 0.73, 0.62 and 1.13 respectively. The mean values for the Radium equivalent, absorbed dose, annual effective dose, and excess lifetime cancer risk from soil are 96.75 Bqkg-1, 47.05 nGyh-1, 0.06 mSvy-1, 0.20×10-3 correspondingly [values from corn are 69.83 Bqkg-1, 35.04 nGyh-1, 0.04 mSvy-1, 0.15×10-3 respectively]. These values clearly showed, the radiation doses exposed to Akwa Ibomites through the consumption of corn cultivated in these areas and inhalation of soil poses no effect to their health. Therefore, there is no radiological risk of ingestion.

Radioactivity levels, soil-to-grass and grass-to-milk transfer factor of natural radionuclides from grazing area in Erbil governorate, Iraq

The levels of naturally occurring radionuclides in soil, grass, and milk were measured in this study in order to calculate the transfer factor of radionuclides from soil to grass and grass to milk obtained from Erbil governorate in Iraq. High efficiency gamma spectrometry used for the measurement. It has been determined that the mean activity concentrations of 232Th, 226Ra, and 40K are 3.08, 8.37, and 253 BqKg−1 in soil, 0.5, 0.39, and 203.05 BqKg−1, in grass, and 0.29, 0.084, and 29.69 BqL−1, in milk, respectively. For soil to grass, the transfer factor values for 232Th, 226Ra, and 40K were found to be 0.18, 0.052, and 0.84, respectively, for soil to grass. For grass to milk, the transfer factor values for 232Th, 226Ra, and 40K were found to be 0.45, 0.166, and 0.11 dayL−1, respectively. The average transfer factor for 232Th, 226Ra, and 40K in all samples were lower than the world average value.

Determine the hazards of radioactive elements and radon gas manufacturing processes in an Egyptian fertilizer factory

This study investigated the levels of radioactivity in soil surrounding a phosphate fertilizer factory in Egypt, aiming to assess potential risks to the population exposed to radiation. Concentrations of 238U, 226Ra, 232Th, and 40K were measured in soil samples collected from two subsites: one near the factory (subsite 1) and another further away (subsite 2). Two different systems were used for measuring radioactivity, a high-purity gamma ray spectroscopy system with an HPGe detector for gamma-emitting isotopes and a CR-39 solid nuclear track detector for alpha-emitting radon gas. Subsite 1, located close to the factory, displayed significantly elevated levels of 226Ra compared to global background levels (514 and 456 Bq/kg vs. 35 Bq/kg). Additionally, the concentrations of 238U (241.06 Bq/kg vs. global average 35 Bq/kg), 232Th (16.15 Bq/kg vs. global average 30 Bq/kg), and 40K (146.36 Bq/kg vs. global average 400 Bq/kg) were all above global averages. Furthermore, a high concentration of radon gas (337.06 μSv/y) was measured at subsite 1. The strong positive correlation observed between 226Ra and 238U (0.96256) provides further evidence of potentially elevated radioactivity levels near the factory. In contrast, subsite 2, situated farther from the factory, exhibited natural radioactive background levels within international limits. Quantitative analysis revealed that gamma ray absorbed doses for 226Ra and 232Th exceeded global averages in some samples. Specifically, 226Ra doses ranged from 7.8 to 46.26 ppm (exceeding the 20 ppm global average in some cases), and 232Th doses ranged from 1.98 to 9.14 ppm (exceeding the 10 ppm global average in some cases). The concentration of 40K, however, remained within the global range (0.07%–0.69 %). The observed imbalances in the ratios of Th/U (0.17–0.24 Bq/kg and 0.73–0.24 ppm) and U/Ra (0.81–0.73 Bq/kg and 0.73–0.17 ppm), both of which are significantly lower than their respective global averages of 4 and 2.4, point towards the presence of fertilizer-derived contamination. This conclusion is further supported by the high phosphate concentrations detected in the samples. Overall, this study suggests that radioactive contamination near the phosphate fertilizer factory significantly exceeds global background levels and international limits in some cases. This raises concerns about potential risks posed to surrounding agricultural land and crops.

Assessment of natural radioactivity levels and potential radiological risks of commonly used building materials in Uttara Kannada District, Karnataka, India.

The main goal of this study is to evaluate the natural radioactivity and potential radiological risks of frequently used building materials in Uttara Kannada district. Using an High purity Germanium Detector (HPGe) detector-based gamma-ray spectrometer, the activity concentration of 226Ra, 232Th and 40K was determined. The activity concentration of 226Ra, 232Th and 40K in the construction materials vary from 13.78±0.90 to 151.9±1.85, 14.21±0.80 to 207.72±2.9 and 55.26±1.20 to 1298.24±25Bqkg-1 with an average value of 40.57±1.37,60.13±1.70 and 425.38±4.75Bqkg-1 having a geometric mean of 33.07, 46.49 and 290.20Bqkg-1, respectively. The mean annual effective dose equivalent was found to be 0.68mSv y-1 and is less than the International Commission on Radiological Protection proposed acceptable limit of 1mSv y-1. The estimated radiological hazard parameters show that these building materials are safe to use in the construction of homes and do not offer a substantial source of radiation hazard.

Uranium Isotope Characterization in Volcanic Deposits in a High Natural Background Radiation Area, Mamuju, Indonesia

Mamuju is an area of high natural radiation in Indonesia with high natural radiation levels (average 613 nSv h−1). Mamuju is anomalous due to its high average 238U and 232Th concentrations of 22,882 and 33,549 Bq kg−1, respectively, in laterite and rock. High natural radionuclide concentrations of 238U, 232Th, and 40K have also been reported in soil samples from several locations in Mamuju, including Botteng, Northern Botteng, Takandeang, Ahu, and Taan. High radiation levels are related to radioactive mineral occurrences in the Adang volcanic complex, comprised of phonolitoid and foiditoid lithologies. According to the International Atomic Energy Agency (IAEA), uranium deposits can be classified into several types, among them a volcanic-related deposits, which include three sub-types: stratabound, structure-bound, and volcano-sedimentary deposits. This study aims to characterize volcanic rock deposit sub-types in the Mamuju area based on uranium radioisotope measurements. The uranium isotopes were measured using a tandem quadrupole inductively coupled plasma mass spectrometer combined with chemical separation by extraction chromatography using UTEVA resin. The analytical results for the 234U/238U ratios are used to determine the formation characteristics of minerals in each deposit sub-type based on mineral formation age, post-formation processes, and disturbances that affected the formation processes. Based on geochronological calculations using 234U/238U mineralization age, the deposits in the Mamuju area are 0.914–1.11 million years old and are classified as recent mineralization. These data have important implications for tracing uranium source rocks in the Mamuju area and may explain the anomalously high radiation levels in the Mamuju area.