A Geological Context in Radiation Risk Assessment to the Public

The work aimed to show the applicability of geological studies to the investigation of radiation risk assessment due to the presence of naturally occurring radionuclides of terrestrial origin in the soil. Soil samples were taken from a Tatra Mountains area for which geological maps were available. The concentration of selected radionuclides incl. ⁴⁰K, ²³⁸U and ²³²Th was determined by gamma-ray spectrometry with a HPGe-detector. Radioactivities and calculated absorbed dose rates were co-related to complex bedrock matrices based on an original methodology. The correlations were proved by performing a Principal Component Analysis (PCA). The rocks that had a significant impact on the rate of absorbed dose from the soil were strongly related to the radioactivity of the uranium series. The share of the following fractions was the most significant: granite with pegmatite, gneiss, granitoid and gneiss, coquina, marl and glauconite, hard limestone, dolomite and limestone. The rock types additionally showed good correlation with radioisotopes from the thorium series. Granitoids with potassium feldspar, on the other hand, contributed the largest share of ⁴⁰K radioisotope content.

Assessment of Natural Radioactivity in Cements Used as Building Materials in Poland

It has been analyzed in this article the radioactivity concentrations of ²²⁶Ra, ²³²Th, ⁴⁰K and radiological hazard parameters in different types of cements commonly used in Poland and available on the Polish market. The radiological hazard parameters are, in particular, absorbed gamma dose rate, annual effective dose, radium equivalent activity, the external hazard index, and the gamma and alpha indices. The radionuclide activities of the most important radionuclides ²²⁶Ra, ²³²Th, ⁴⁰K have been determined by gamma-ray spectrometry with the use of two kinds of spectrometers of different operational parameters. One performed also measurements on 30-day and 45-day aged samples as to verify if there is a statistically significant difference in radioactivity concentration for shorter and longer aging time. The radioactivity concentrations in the cement samples ranged from 21.7-75.7 Bq·kg^-1 for ²²⁶Ra, 12.3-47.3 Bq·kg^-1 for ²³²Th to 123-430 Bq·kg^-1 for ⁴⁰K. The radiological parameters in cement samples were calculated as follows: mean radium equivalent activity Ra_eq = 127 Bq·kg^-1, mean absorbed gamma dose rate D = 115 nGy·h^-1, mean annual effective dose E = 570 µSv·y^-1, external hazard index H_ex = 0.32, internal hazard index H_in = 0.51, mean activity concentration index I_γ = 0.47 and mean alpha index I_α = 0.28. The results were compared with the reported data from other countries and the international standard values given by European Commission (EC) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR 2000). Finally, thorough statistical analysis has been performed.

Multivariate Statistics, Mineralogy, and Radiological Hazards Assessment Due to the Natural Radioactivity Content in Pyroclastic Products from Mt. Etna, Sicily, Southern Italy

In this article, an investigation of the natural radioactivity content of pyroclastic products from Mt. Etna, eastern Sicily, Southern Italy, was carried out. In particular, the assessment of the average activity concentration of the investigated radionuclides, related to the mineralogical phase composition of the analyzed samples, and the radiological health risk for the population, was performed. High Purity Germanium (HPGe) gamma-ray spectrometry was employed in order to quantify the average specific activity of ²²⁶Ra, ²³²Th, and ⁴⁰K natural radioisotopes. The absorbed gamma dose rate (D), the radium equivalent activity (Ra_eq), the hazard indices (H_in and H_ex), the annual effective dose equivalent outdoor (AEDE_out), and the excess lifetime cancer risk (ELCR) were also estimated in order to assess any possible radiological hazard for the population. In our case, they were found to be lower than the maximum recommended values for the population members, thus reasonably excluding radiological hazard effects. Moreover, the identification of the source of the aforementioned naturally occurring radionuclides was attempted by X-ray Diffraction (XRD) and Micro-Raman Scattering (MRS), thereby recognizing the main radioisotope-bearing minerals present in the investigated pyroclastic products. Finally, Pearson correlation, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis (HCA) were performed by processing observed radioactivity and radiological parameters in order to determine their correlation with the sampling locations.

Distribution of Radionuclides and Radiological Health Assessment in Seih-Sidri Area, Southwestern Sinai

The current contribution goal is to measure the distribution of the radionuclide within the exposed rock units of southwestern Sinai, Seih-Sidri area, and assess the radiological risk. Gneisses, older granites, younger gabbro, younger granites, and post granitic dikes (pegmatites) are the main rock units copout in the target area. Radioactivity, as well as radiological implications, were investigated for forty-three samples from gneisses (seven hornblende biotite gneiss and seven biotite gneiss), older granites (fourteen samples), and younger granites (fifteen samples of syenogranites) using NaI (Tl) scintillation detector. External and internal hazard index (H_ex, H_in), internal and external level indices (Iα, Iγ), absorbed dose rates in the air (D), the annual effective dose equivalent (AED), radium equivalent activity (Ra_eq), annual gonadal dose (AGDE), excess lifetime cancer risk (ELCR), and the value of Upper Continental Core ²³²Th/²³⁸U mass fractions were determined from the obtained values of ²³⁸U, ²³²Th and ⁴⁰K for the examined rocks of Seih-Sidri area. The average ²³⁸U mg/kg in hornblende biotite gneiss and biotite gneiss, older granites, and syenogranites is 2.3, 2.1, 2.7, and 8.4 mg/kg, respectively, reflecting a relatively higher concentration of uranium content in syenogranites. The results suggest that using these materials may pose risks to one's radiological health.

Radiological risks from 40 K, 226Ra and 232Th in urbanised and industrialised karstic coastal area (Kaštela Bay, Croatia)

Radiological risks associated with ⁴⁰ K, ²²⁶Ra and ²³²Th massic activities in limestones, marls, stream sediments and soils of the Kaštela Bay (Croatia) coastal area were assessed by calculating outdoor absorbed dose rates in air (D), annual outdoor effective dose rates (D_ef), radium equivalent activities (Ra_eq) and external hazard indices (H_ex). Radionuclides relative contributions to D and H_ex were determined for all four types of samples as well as their total contribution to H_ex in all samples. D, D_ef, Ra_eq and H_ex were the lowest in limestones and the highest in soils. Maximum Ra_eq and H_ex in soil were below the recommended values of 370 Bq/kg and 1.0. No adverse radiological effects were determined in the researched area. The most important contribution to D and H_ex in limestones was almost exclusively from ²²⁶Ra, in marls from ⁴⁰ K, in stream sediments from ²²⁶Ra and in soils from ²³²Th. The most significant total contribution to H_ex in all samples came from ²²⁶Ra and ²³²Th, and the lowest came from ⁴⁰ K. ²²⁶Ra showed the largest variability of its total contribution to H_ex, with tendency to higher values. Special attention should be given to ²²⁶Ra when studying radiological risks in typical karstic areas, irrespectively of other possible influences of geological background.

Soil to tobacco component transfer factors for natural radionuclides 40K, 226Ra, and 232Th and the risk assessment of tobacco leaf in smoking

This study determined the activity concentrations and corresponding transfer factors (TF) of ⁴⁰K, ²²⁶Ra, and ²³²Th in three tobacco components (root, stem, and leaf). The radiation hazard index parameters were assessed for the tobacco leaf. The activity concentrations in the soil were 589-762, 32-43, and 49-59 Bq kg-dw^-1 (dry weight) for ⁴⁰K, ²²⁶Ra, and ²³²Th, respectively. The average activity concentrations of ⁴⁰K, ²²⁶Ra, and ²³²Th were 447, 5.41 and 5.69 Bq/kg-dw for the root, 670, 9.64 and 7.61 Bq kg-dw^-1 for the stem, and 793, 6.79 and 6.15 Bq kg-dw^-1 for the leaf, respectively. The TF values were 0.42-1.42, 0.10-0.49 and 0.06-0.23 for ⁴⁰K, ²²⁶Ra, and ²³²Th, respectively. The stem and leaf ⁴⁰K TF values were significantly higher than the root values. The stem ²²⁶Ra TF values were significantly higher than the root values. The ²²⁶Ra and ²³²Th activity concentrations and TFs of tobacco components had a significant positive correlation. Based on the activity concentrations of the tobacco leaves, the annual inhalation effective dose to the lungs for an adult smoker was 0.32-0.81 mSv y^-1 (average 0.60 mSv y^-1). The Excess Lifetime Cancer Risk (ELCR) caused by smoking was an average of 2.39 × 10^-3.

Evaluation of Radiological Health Risks in Popularly Consumed Brands of Sachet Water in Nigeria

Radiological investigation of 35 brands of most popularly used sachet drinking water in Ondo state, Nigeria has been carried out using a spectrometric method for evaluating the concomitant health risks to the members of the public. Activity concentrations of the investigated radionuclides ⁴⁰K, ²²⁶R, and ²²⁸Ra were in the range from 16.35 ± 4.10 to 199.94 ± 38.40 Bq L⁻¹ with an arithmetic mean (AM) of 66.22 ± 54.99 Bq L⁻¹, from 1.35± 0.79 to 17.06 ± 5.13 Bq L⁻¹ with an AM of 6.88 ± 3.66 Bq L⁻¹, and from 1.95 ± 0.08 to 17.22 ± 3.87 Bq L⁻¹ with an AM of 9.49 ± 4.98 Bq L⁻¹, respectively. The determined annual effective doses and the corresponding excess lifetime cancer risks due to ²²⁶Ra and ²²⁸Ra were found to exceed the acceptable limits of 0.1 mSv y⁻¹ and 10⁻³ respectively, as suggested by the World Health Organization (WHO). This implies a non-negligible carcinogenic health hazard due to the intake of the surveyed drinking water, especially for the lactating babies (0–1) y and teenagers (12–17) y. The data from this research may form an invaluable component of radiometric values of the database in Nigeria, as well as the world for setting up guidelines and control policies for the use of sachet water.

An In-Depth Examination of the Natural Radiation and Radioactive Dangers Associated with Regularly Used Medicinal Herbs

The specific activity of U-238 and Th-232, as well as K-40 radionuclides, in twenty-nine investigated medicinal herbs used in Egypt has been measured using a high-purity germanium (HP Ge) detector. The measured values ranged from the BDL to 20.71 ± 1.52 with a mean of 7.25 ± 0.54 (Bq kg−1) for uranium-238, from the BDL to 29.35 ± 1.33 with a mean of 7.78 ± 0.633 (Bq kg−1) for thorium-232, and from 172 ± 5.85 to 1181.2 ± 25.5 with a mean of 471.4 ± 11.33 (Bq kg−1) for potassium-40. Individual herbs with the highest activity levels were found to be 20.71 ± 1.52 (Bq kg−1) for uranium-238 (H4, Thyme herb), 29.35 ± 1.33 (Bq kg−1) for thorium-232 (H20, Cinnamon), and 1181.2 ± 25.5 (Bq kg−1) for potassium-40 (H24, Worm-wood). (AACED) Ingestion-related effective doses over the course of a year of uranium-238 and thorium-232, as well as potassium-40 estimated from measured activity concentrations, are 0.002304 ± 0.00009 (minimum), 0.50869 ± 0.0002 (maximum), and 0.0373 ± 0.0004 (average)(mSv/yr). Radium equivalent activity (Raeq), annual gonadal dose equivalent (AGDE), absorbed gamma dose rate (Doutdoor, Dindoor), gamma representative level index (I), annual effective dose (AEDtotal), external and internal hazard index (Hex, Hin), and excess lifetime cancer risk were determined in medicinal plants (ELCR). The radiological hazards assessment revealed that the investigated plant species have natural radioactivity levels that are well within the internationally recommended limit. This is the first time that the natural radioactivity of therapeutic plants has been measured in Egypt. In addition, no artificial radionuclide (for example, 137Cs) was discovered in any of the samples. Therefore, the current findings are intended to serve as the foundation for establishing a standard safety and guideline for using these therapeutic plants in Egypt.

Effect of natural radionuclide's in the environment along the Jwalamukhi thrust of Himachal Pradesh, North West Himalayas, India

This research paper is devoted to measure the activity contents of natural radionuclide, like, radium (²²⁶Ra), thorium (²³²Th) and potassium (⁴⁰K) in the soil gathered along the Jwalamukhi thrust of Himachal Pradesh, North Western Himalayas, India. NaI(Tl) Scintillator detector was utilized for the estimation of activity content. The activity concentration of ²²⁶Ra, ²³²Th and ⁴⁰K for some of the soil samples have been observed to be above the global normal mean values. The outcomes acquired for indoor and outdoor effective dosage are well below the normal international and national proposed results. The determined values of external hazard (H_ex) for studied locations are less than unity, therefore; samples assembled from these regions are safe from a health hazard point of view and can be utilized as a construction purposes without producing any radio-logical hazard to human beings. The average estimations of radium equivalent activity were found to be within the limits suggested by Organization for Economic Cooperation and Development (OECD). Radon (²²²Rn) and thoron (²²⁰Rn) exhalation rates have also been calculated and discussed.

Natural radioactivity assessment and geophysical interpretation of parts of Igarra area, Southern Nigeria

To evaluate the concentration of natural radionuclides and to carry out geophysical interpretation of part of Igarra area, Southern Nigeria, an integrated geophysical approach was adopted involving radiometric, gravity, and magnetic methods. The RS-230 Super-Spec spectrometer, G-512 Lacoste and Romberg gravimeter, and the GSM-19v7.0 Overhauser instrument were used for the radiometric, gravity, and magnetic data acquisitions, respectively, along a specified traverse within the area. The datasets were processed using Oasis Montaj, Grav-Master, and Ms-Excel software. Gravity results show that the mean free air and Bouguer anomalies in the area are - 67.42 and - 84.22 mGal, while magnetic survey indicates that the mean corrected magnetic field intensity in this area is 32218.49 nT. Radiometric survey results show that the mean radioactivity concentrations of thorium ([Formula: see text], uranium ([Formula: see text]), and potassium ([Formula: see text]) are 31.81 Bq/kg, 26.48 Bq/kg, and 167.33 Bq/kg, respectively. Further analysis also revealed that the mean radioactivity equivalent of the area is 84.86 Bq/kg; absorbed dose rate is 72.74nGy/h, while the mean external hazard index is 0.30. A novel model equation for estimating absorbed dose rate from radioactivity equivalent was also obtained and validated. The gravity and magnetic survey results indicate the presence of low-density and high magnetic basement rocks underlying this area, while radiometric results reveal that radiations in this area did not exceed acceptable standards of 370 Bq/kg for radioactivity equivalent, 84 nGy/h for absorbed dose rate, and unity which corresponds to 370 Bq/kg for external hazard index as recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation and the International Atomic Energy Agency.

Radioactive risk assessment of beach sand along the coastline of Mediterranean Sea at El-Arish area, North Sinai, Egypt

Beach sand includes various levels of natural radioactivity, which can cause health effects. The natural radioactivity was measured in the beach sand along the coastline of the Mediterranean Sea at the east of the El-Arish area, Egypt. Using the HPGe spectrometer, the contribution of radionuclides ²²⁶Ra, ²³²Th and ⁴⁰K in the gamma emitted radiation illustrated that the ²²⁶Ra, ²³²Th and ⁴⁰K activity concentrations are 8.8 ± 3.9, 30.8 ± 12.2 and 106.9 ± 46.8 Bq kg^-1, respectively, which is lower than the reported worldwide limit 33, 45 and 412 Bq kg^-1. The radioactive hazards associated with the beach sand along the coastline of the Mediterranean Sea at the east of the El-Arish area were investigated. The obtained results among the radiological hazard parameters, the radium equivalent content (Ra_eq), the absorbed dose rate (D_air), annual effective dose (AED), external (H_ex) and internal (H_in) hazard indices were estimated. Moreover, the excess lifetime cancer risk (ELCR) and the annual gonadal dose equivalent (AGDE) were also computed and illustrated their values less than the recommended levels. Multivariate statistical approaches like Pearson correlation, the principal component analysis (PCA) and the hierarchical cluster analysis (HCA) were applied to investigate the correlation between the radionuclides and the corresponding radiological hazard variables. Based on the statistical analysis, the ²²⁶Ra and ²³²Th mainly contribute to the radioactive risk of beach sand. Finally, no significant risk of the public associated with utilizing beach sand in building materials.

RADIOACTIVITY CONTENT OF BUILDING MATERIALS USED IN KUTAHYA PROVINCE, TURKEY

Radioactivity concentrations of primordial radionuclides Ra-226, Th-232 and K-40 for 31 samples of seven different types of construction materials used in Kütahya Province, Turkey, were analyzed using NaI(Tl) gamma spectroscopy. Ra-226, Th-232 and K-40 activities of all samples ranged between <2.0 and 81.3 ± 1.5, <1.0 and 24.8 ± 0.5 and <7.8 and 819.1 ± 5.5 Bq kg -1, respectively. Radium equivalent activity and Gamma index of sampled building materials were calculated and presented. All results were found to be below the safety limits.

Radiological risk assessment in sediment of Namal Lake, Mianwali, Pakistan

This study is concentrated on the radiological risk assessment of sixteen surface sediment samples recovered from Namal Lake, District Mianwali, Punjab, Pakistan. The activity of ¹³⁷Cs, ⁴⁰ K, ²²⁶Ra, ²²⁸Ra, and ²³²Th was carried out with the help of a high purity germanium detector (HPGe) in the sediment, varied in the ranges of > 0.02-3.73 ± 1.31, 98.32 ± 21.45-341.02 ± 58.67, 18.34 ± 2.16-34.23 ± 4.34, 1.62 ± .30-2.34 ± .52, and 0.14 ± 0.10-2.34 ± 0.59 Bq kg^-1 with average values 0.74 ± 0.29, 237.26 ± 37.97, 25.06 ± 4.74, 1.97 ± 0.39, and 1.73 ± 0.33 Bq kg^-1, respectively. The measured concentrations in the current study have been compared with other earlier studies in the world. The data was also used for determining the other useful parameters like radium equivalent activity, absorbed dose rate, annual effective dose rate, and external and internal hazards index to assess the radiological risk assessment for the environment around the study area. The ERICA Tool software was also applied for radiological risk assessment for lake fish due to the radioactivity present in the lake sediments. It was concluded from the results of ERICA tool that the risk quotient in this study is less than one indicating that no toxic effects of radioactivity for Namal Lake fish.

Evaluation of natural radioactivity levels and potential radiological hazards of common building materials utilized in Mediterranean region, Turkey

Radiometric measurement of building materials is very important to assess the internal and external exposure caused by the ionizing radiation emitted from terrestrial radionuclides in building materials. The activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K in fifty-eight samples of fifteen different structural and covering building materials commonly used in Osmaniye province located in the Mediterranean region of Turkey were measured by using gamma-ray spectroscopy. The activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K varied from 2.5 ± 0.1 (marble) to 145.7 ± 4.4 (clay brick), 1.3 ± 0.1 (marble) to 154.3 ± 4.1 (marble), and 8.6 ± 0.2 (sand) to 1044.1 ± 70.3 (granite), respectively. Radiological parameters (activity concentration index, alpha index, indoor absorbed gamma dose rate and the corresponding annual effective dose rate, and excess lifetime cancer risk) were estimated to evaluate the health hazards associated with these building materials. Since the estimated values of these parameters are within the recommended safety limits or criteria values, the use of the studied building materials in the construction of dwellings can be considered to be safe for the residents of the region.

Radiological monitoring in some coastal regions of the Saudi Arabian Gulf close to the Iranian Bushehr nuclear plant

We studied the concentrations of terrestrial and anthropogenic radionuclides in seawater and shore sediment/sand of three selected regions; Khafji, Safaniyah and Menifah along the Saudi Arabian Gulf coast. The mean activity concentrations of the ²²⁸Ra, ²²⁶Ra, and ⁴⁰K in the analyzed sand samples are 5.9, 3.5 and 113.5 Bq/kg, and the respective values in seawater samples are 1.6, 0.8 and 10.4 Bq/L. All data show lower than the corresponding UNSCEAR (2000) reported world average values of 35, 30 and 400 Bq/kg for soil matrix. A few relevant radiological hazards were quantified by the estimation of the absorbed dose rate, and the results are compared with the prescribed limits set by international regulatory bodies. Measured data indicates that the studied coastal regions pose a negligible radiological hazards to the public, and show an insignificant radioactive loading to this coastal region by the Busher nuclear power plant.

Assessing the Radiological Risks Associated with High Natural Radioactivity of Microgranitic Rocks: A Case Study in a Northeastern Desert of Egypt

This study aimed to evaluate the radiological hazards of uranium (²³⁸U), thorium (²³²Th), and potassium (⁴⁰K) in microgranitic rocks from the southeastern part of Wadi Baroud, a northeastern desert of Egypt. The activity concentrations of the measured radionuclides were determined by using a gamma-ray spectrometer (NaI-Tl-activated detector). The mean (²³⁸U), (²³²Th), and (⁴⁰K) concentrations in the studied rocks were found to be 3680.3, 3635.2, and 822.76 Bq/kg, respectively. The contents in these rocks were elevated, reaching up to 6.3 wt%. This indicated the alkaline nature of these rocks. The high ratios of Th/U in the mineralized rocks could be related to late magmatic mineralization, suggesting the ascent of late magmatic fluids through weak planes such as faults and the contact of these rocks with older granites. The present data were higher than those of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) guideline limits. All the radiological hazard results indicated high human health risks. This confirmed that this area is not radiologically safe, and care must be taken when working in this area. This study showed that the area under investigation had high U content suitable for uranium extraction that could be used in the nuclear fuel cycle.

AGE-DEPENDENT DOSE DUE TO INTAKE OF 40K, 228RA, 226RA IN SPRING WATER IN PETRA DISTRICT, JORDAN

A HpGe detector was used to measure radioactivity concentrations of 40K, 228Ra and 226Ra in spring water from villages in Petra district in southern Jordan. The concentrations of 40K, 228Ra, 226Ra were 0.64-2.72 Bq/l, 0.05-0.08 Bq/l and 0.15-0.22 Bq/l, respectively. These values were compared to the concentrations of the corresponding radionuclides in studies from Jordan and near countries. The annual effective doses (${D}_{\mathrm{eff}}$) due to the intake of 40K, 228Ra and 226Ra, for the different age groups were calculated. The highest ${D}_{\mathrm{eff}}$ values due to the intake of 226Ra and 228Ra were found in the infants age group, whereas the lowest were found in the adults age group in every site. The annual effective doses in this study were compared to the committed annual effective doses from ingestion in UNSCEAR. The annual effective doses in this study were much higher than the committed values in UNSCEAR. The life time risk for radiation-induced cancer for the whole population was calculated for every sample and it revealed no extra risk over the one recommended by WHO.

Natural radioactivity levels in benthic foraminifera Sorites marginalis as a pollution indicator

Sorites marginalis as one of the benthic foraminifer's genera were collected from three coastal lagoons (Abu Shaar, Umm al-Huwaytāt, and Marsa Shūni) on the Egyptian Red Sea coast and investigated for their ²²⁶Ra, ²³²Th, and ⁴⁰K content using HPGe gamma-ray spectrometry. S. marginalis shells show high radioactivity levels with average activity concentration values of 251.8 ± 18.3, 86.8 ± 7.7, and 791.2 ± 57.6 Bq kg^-1, 327.1 ± 11.4, 97.4 ± 7.1, and 751.6 ± 54.7 Bq kg^-1, 246.6 ± 17.7, 65.1 ± 4.8, and 477.6 ± 34.8 Bq kg^-1 for ²²⁶Ra, ²³²Th, and ⁴⁰K in the samples from Abu Shaar, Umm al-Huwaytāt, and Marsa Shūni, respectively. ²²⁶Ra and ⁴⁰K have a high tendency to accumulate in S. marginalis compared to ²³²Th. High bioaccumulation of the studied radionuclides was found for samples from Umm al-Huwaytāt and Abu Shaar lagoons. Radiological parameters such as radium equivalent activity, gamma absorbed dose rate in air, and outdoor annual effective dose were calculated, and values higher than the permissible limits were obtained. Based on the obtained results, the estimation of radioactivity levels in S. marginalis shells may serve as an indicator of marine environment pollution.

Investigations on baseline levels for natural radioactivity in soils, rocks, and lakes of Larsemann Hills in East Antarctica

A comprehensive measurement of concentrations of the natural radionuclides ²³⁸U, ²³²Th and ⁴⁰K, and ²²⁶Ra in the soil and rocks along with natural uranium and tritium activity levels in lake water were carried out during the Indian expedition to Antarctica. The samples were collected from the Larsemann Hills region in Antarctica (latitude 69°20' S to 69°25'S, longitude 76°6' E to 76°23'E). The data on the natural radioactivity for this region is limited. The study was carried out to establish baseline levels of radioactivity in different terrestrial matrices of this region such as soil, rocks, and lake water. A radiation survey mapping for terrestrial radioactivity was conducted in the region before collection of soil and rock samples. The soil and rock samples were analyzed for natural radioactivity concentrations using high-resolution gamma spectroscopy system. The major contributor to elevated gamma radiation background is attributed to the higher concentration of ²³²Th and ⁴⁰K radionuclides in both soil and rocks. Terrestrial components of gamma dose rate due to natural radioactivity have been estimated from the measured radioactivity concentrations and dose conversion coefficients. Several "hotspots" and high background areas in the region have been identified having significantly higher concentration of ²³²Th and ⁴⁰K. Rocks in Larsemann Hills region showed high reserve of thorium mineralization in monazites and ⁴⁰K in K-feldspar. The concentrations of ²³²Th in soil are found to be in the range of 106-603 Bq/kg, whereas in rock it is in the range of 8-4514 Bq/kg. Natural radioactivity U (nat) and ³H contents in the lake water samples in Larsemann Hills region were estimated as 0.4 and 1.3 Bq/L and are well within the prescribed limit of radioactivity in drinking water as recommended by World Health Organization.

NATURALLY OCCURRING RADIONUCLIDE 40K BODY CONTENT OF KAKRAPAR GUJARAT SITE POPULATION

An attempt was made to investigate the naturally occurring radionuclide 40K body content of the Kakrapar Gujarat Site (India) population by using whole-body counting method. The population comprises occupational workers (regular and contract personnel working at Kakrapar Atomic Power station) and students from various educational institutions. A total of 1056 subjects of different age groups and gender were monitored for 40K body content by using a Standfast-II Whole Body Counting System. The reactor released radionuclides such as 137Cs, 60Co and 131I are not detected in occupational workers of Kakrapar Atomic Power station which indicates that occupational workers are free from radioactive contamination. Based on the activity measurement, an effective dose due to 40K was estimated for different groups of the site population based on the dietary habits, sex and age. Statistical significant correlation was not observed in any of the groups. The annual effective dose due to 40K was found to be in the range of 52-243 μSv y-1 with an average of 133 ± 35 μSv y-1 for the vegetarian group (588 subjects), 60-223 μSv y-1 with an average of 136 ± 35 μSv y-1 for the non-vegetarian group (468 subjects), 52-243 μSv y-1 with an average of 134 ± 35 μSv y-1 for the male group (1007 subjects) and 67-203 μSv y-1 with an average of 128 ± 35 μSv y-1 for the female group (49 subjects), respectively. Among the four age groups of the population studied, an effective dose due to 40K is slightly higher in the age group of 20-29 (161 subjects). The annual effective dose due to 40K reported by UNSCEAR, 1982(3) is 180 μSv y-1.

Evaluation of naturally occurring radioactive materials (NORM) in the soil, in a potential area for unconventional reservoirs in the Rancheria Sub-Basin

Naturally occurring radioactive elements depend on lithology geogenic characteristics, such as depositional, environmental, or diagenetic. Thus, evaluating these elements constitutes a tool to define ionizing radiation effect from rocky sequences. This study carried out in the Rancheria Sub-Basin establishes both characterization and assessment of this kind of material, known as NORM. The sampling included uranium-238, thorium-232, potassium-40, radon-226, and radon-222 in soil samples, cutting samples from the Molino-1 well, and radon in surface water. Bases on a radiometric methodology with a gamma-ray spectrometer for uranium-238, thorium-232, and potassium-40 and emanometric with ionizing chambers for radio-226 and radon-222. The analysis and results of the activity concentrations in soil samples of U-238, Th-232, K-40, and Ra-226 are 11.7 BqKg^-1, 33.0 BqKg^-1, 424.5 BqKg^-1, and 15.59 BqKg^-1, respectively, among the acceptable global averages. However, in some areas, observed values indicate high activity concentrations of U-238, Th-232, K-40, Ra-226, and Rn-222 in the soil of 50.2 BqKg^-1, 62.8 BqKg^-1, 1596.3 BqKg^-1, 44.25 BqKg^-1, and 112546.79 Bqm^-3, respectively. Those activity concentrations were associated with zone lithology.

Assessment of a naturally occurring high background radiation area with elevated levels of thorium along coastal Odisha, India using radiometric methods

The present study evaluates the enrichment and distribution of radioelements along the eastern coast of India. India possesses the second largest reserve of thorium bearing monazite in the world, in terms of heavy minerals present primarily along its long coastline. Radioelement estimation of about 30 km long beach area along the eastern coast of India is reported and implications discussed. A total number of 822 data points were studied using a portable Geiger Muller counter, to estimate the variation of dose rates, due to the ambient radionuclides along two different trends. One was parallel (northeast-southwest) and the second one perpendicular to the coastline. Pre-selected samples from in-situ radiometric surveys on the heavy mineral placers were studied further, for quantitative estimation of the abundance of radioactive elements primarily uranium and thorium, using a High Purity Germanium detector. Radioelement concentration assessment of core samples (depth ~2 m), were studied from two different beaches. Radiological parameters like radium equivalent, annual effective doserate and absorbed dose rate has been calculated based on the ²³⁸U, ²³²Th and ⁴⁰K concentrations. Heavy mineral placers along the shoreline indicate a very high thorium (avg - 2990.22 Bq kg^-1) which is due to the extensive distribution indicative of monazite. The coastal area also exhibits relatively low uranium (avg - 319.1 Bq kg^-1). Based on its high thorium concentration, the area can be considered as a high natural background radiation area. Based on the concentrations of uranium and thorium, the weathering conditions and depositional environment prevalent along the beach areas have been discussed.

Pietra Leccese and Other Natural Stones in Puglia Region: A New Category of Building Materials for Radiation Protection?

In this paper, an in-depth and systematic study of the radiological characterization of three types of Puglia region natural limestones (Pietra Leccese, Pietra Mazzara and Carparo) was carried out. The investigation was performed by XRF spectroscopy for a chemical analysis, and gamma spectroscopy of the specific activity concentration of natural radionuclides ²²⁶Ra, ²³²Th, and ⁴⁰K. Although the limestone does not fall within the category included by Italian Legislative Decree 101/2020, the gamma index was calculated using the results of the gamma spectroscopy measurements. For Pietra Mazzara and Carparo stones, the gamma index was found to be less than the reference value; conversely Pietra Leccese was found to be higher. To obtain a more complete evaluation of the external exposure, radium equivalent activity and external radiation hazard were calculated for all analyzed stones. The results suggest the need to broadly consider the radiological risk for these stones, and for limestone more generally, when used as a building material.

Naturally Occurring Radioactive Materials in Bracelets and Necklaces: Radiological Risk Evaluation

A particular category of jewelry is one involving bracelets and necklaces that are deliberately made to contain naturally occurring radioactive material (NORM)-purveyors making unsubstantiated claims for health benefits from the release of negative ions. Conversely, within the bounds of the linear no-threshold model, long-term use presents a radiological risk to wearers. Evaluation is conducted herein of the radiological risk arising from wearing these products and gamma-ray spectrometry is used to determine the radioactivity levels and annual effective dose of 15 commercially available bracelets (samples B1 to B15) and five necklaces (samples N16 to N20). Various use scenarios are considered; a Geant4 Monte Carlo (Geant4 MC) simulation is also performed to validate the experimental results. The dose conversion coefficient for external radiation and skin equivalent doses were also evaluated. Among the necklaces, sample N16 showed the greatest levels of radioactivity, at 246 ± 35, 1682 ± 118, and 221 ± 40 Bq, for ²³⁸U, ²³²Th, and ⁴⁰K, respectively. For the bracelets, for ²³⁸U and ²³²Th, sample B15 displayed the greatest level of radioactivity, at 146 ± 21 and 980 ± 71 Bq, respectively. N16 offered the greatest percentage concentrations of U and Th, with means of 0.073 ± 0.0002% and 1.51 ± 0.0015%, respectively, giving rise to an estimated annual effective dose exposure of 1.22 mSv, substantially in excess of the ICRP recommended limit of 1 mSv/year.

An extended assessment of natural radioactivity in the sediments of the mid-region of the Egyptian Red Sea coast

In this study, nearly 84 marine sediment samples were collected from twelve points in four cities (Quseir, Safaga, Hurghada, and Ras Gharib) along the Egyptian Red Sea sectors. The collected samples were extensively examined to estimate the natural radioactivity level. The obtained results were compared to the reported ranges from other locations in different countries. Hazardous radiation parameters such as radium equivalent, annual dose, and external hazards were estimated and compared to United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) recommended levels. The values were recorded in the first natural radioactivity database of coastal sediments from Egyptian Red Sea cities. The dose rate for certain organs was evaluated. The results showed that Red Sea beach sediments are safe in terms of natural radioactivity. It can be concluded that they do not pose a risk to tourists going to the beaches for recreation or to sailors and fishers involved in economic activities along the Egyptian Red Sea coast.