Natural and anthropogenic radionuclides in rocks and beach sands from Ezine region (Çanakkale), Western Anatolia, Turkey

Estimation of natural radioactivity and radiological hazards in river sediments (sand) used as building materials in South Africa

This study presents an investigation into the natural radioactivity levels of 238U, 232Th, and 40K using a thallium-doped sodium iodide (NaI(TI)) detector and associated radiological hazards in river sediments, specifically sand, which serves as a crucial building material in the KwaZulu-Natal Province of South Africa. The assessment aims to provide insights into potential radiological risks posed by the utilization of these sediments in construction activities. The mean activity concentrations of 238U, 232Th, and 40K are 145.33, 38.67, and 362.67 Bq kg-1, 124.64, 60.60, and 353.00 Bq kg-1, 144.00, 48.80, and 371.00 Bq kg-1, 92.95, 52.00, and 368.75 Bq kg-1, 133.55, 45.60, and 324.40 Bq kg-1, and 109.50, 52.50, 381.50 Bq kg-1 for Umngeni River, Umsunduzi River, Ashburton Sarupen, Hammersdale, Kwanjobekazi, and Cator Ridge, respectively. The obtained values of the radiological hazard indices (radium equivalent activity, external hazard index, internal hazard index, and activity utilization index) were below the world average values reported for building materials. Therefore, the studied samples are radiologically safe for use as building materials in the study area because they may not constitute any severe radiological hazards to residents.

Review and statistical analysis of activity values reported for coastal sands worldwide

The activity of natural radionuclides is unevenly distributed across the Earth's crust, with certain areas exhibiting significantly higher levels than others, known as High Background Radiation Areas (HBRAs). This study presents a statistical analysis of reported activity values for coastal sands globally. Through this statistical analysis, costal sands were classified into four categories based on their activity levels, providing a standardized framework to compare the natural radioactivity of these sands. This classification is a valuable tool for identifying populations exposed to different radiation levels, which is essential for the study of stochastic effects. The study proposes thresholds to define HBRAs as regions with activity values exceeding 203 Bq/kg for 238U, 517 Bq/kg for 232Th, or 960 Bq/kg for 40K. Regions with lower values are classified as NonHBRAs. Further subdivision of these categories resulted in four distinct regions: NonHBRA-, NonHBRA+, HBRA-, and HBRA+. The activity values for these subdivisions are 92 Bq/kg and 2,903 Bq/kg for 238U, 94 Bq/kg and 7,230 Bq/kg for 232Th, and 901 Bq/kg and 2,298 Bq/kg for 40K. By calculating the external dose rates from the reported activity data, a threshold of 357 nGy/h was identified as the dose boundary separating NonHBRAs from HBRAs. The values for the subdivisions resulted 101 nGy/h and 3,867 nGy/h. The study also explores the content of these natural radionuclides in relation to their bearing minerals and discusses correlations between the reported activity values and the characteristics of the sands. Additionally, the activity of the anthropogenic radionuclide 137Cs (reported values ranging from the detection limit to 63 Bq/kg) is examined.

UAV-based RGB and TIR imaging for geothermal monitoring: a case study at Kestanbol geothermal field, Northwestern Turkey

Kestanbol is one of the most important geothermal fields in NW Turkey. This study conducted the first-ever surveys over a 10 ha reach of the Kestanbol geothermal field using an unmanned aerial vehicle (UAV) equipped with visible (RGB) and thermal infrared (TIR) cameras. Low-altitude flights below 40 m above the ground were operated above the Kestanbol geothermal field. Approximately 3500 RGB and TIR images were captured using the UAV. We recorded high-resolution RGB and TIR data of the Kestanbol geothermal field and applied the structure from motion (SfM) algorithm to identify the distribution of geothermal springs and seeps. The Kestanbol geothermal field was monitored to create a georeferenced RGB orthophoto, RGB 3D surface model, thermal anomaly map, and digital surface model (DSM) of the area with centimeter-level accuracy. In the TIR orthophoto, the surface temperature in the geothermal field was found to be between 15 and 75 °C. All the thermal anomalies revealed by the survey were verified by field observations. The geothermal springs and seeps were parallel to the NE-SW regional tectonic trends. The results of this study demonstrate an effective technique for monitoring and assessing geothermal water using UAV-based RGB and TIR imaging and provide an accurate basis for geothermal development projects. RGB and TIR imaging using UAVs are considered promising methods for improving the assessment of the effects of geothermal water on the environment.

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.

Carbon dioxide emissions mitigation strategy through enhanced geothermal systems: western Anatolia, Turkey

Although Turkey is not the biggest GHG polluter, its emissions have increased by 110.4% since 1990. Currently, its CO₂ emissions alone have crossed 400 Mt. Within the scope of 2 °C targets (2D scenario), the country can easily surpass this target test by increasing its renewable energy sources as a primary energy source mix, by developing its Enhanced Geothermal Sources (EGS) locked up in the radiogenic granites of western Anatolia. The radiogenic heat generated by these granites, spread over an area of 4221 sq. km, varies from 5.3 to 16.34 µW/m³. Based on the electricity generation capacity of granites from Soultz-sous-Forets and Cooper Basin EGS sites, the combined electricity generation capacity of Kestanbol and Kozak granite plutons is about 830 billion kWh. For the period extending from 2019 to 2023, Turkey is aiming at reducing the usage of gas for electricity generation from 29.9 to 20.7%, increasing the share of renewable energy sources from 32.5 to 38.8%, increasing the electricity production from local energy sources from 150 to 219 TWh and increasing the electricity usage per-capita from 3.7 to 4.3 MWh. These energy targets can be achieved by major contributions from hydrothermal and EGS energy sources. This review demonstrates that besides electricity and heat, EGS energy can be utilized, together with other renewable energy sources, such as hydrothermal, wind, and concentrated solar for providing fresh water through the desalination process. These energy sources would provide food, energy, and water security to the country for several decades.

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.

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.

Radioactivity, Metals Pollution and Mineralogy Assessment of a Beach Stretch from the Ionian Coast of Calabria (Southern Italy)

In the present article, a case study is reported regarding an investigation carried out in order to assess radioactivity concentration, heavy metals pollution and mineralogy of a beach stretch extending from Soverato to Squillace municipalities of the Ionian coast of Calabria, South of Italy, a popular tourist destination, especially in summer. The analysis of radionuclides contents was performed by using a High Purity Germanium (HPGe) gamma-ray detector, in order to quantify the average specific activity of ²²⁶Ra, ²³²Th and ⁴⁰K natural radionuclides and ¹³⁷Cs anthropogenic radioisotope. The absorbed dose rate and the annual effective dose equivalent radiological hazard indices were also estimated. Furthermore, X-ray Fluorescence (XRF) spectrometry measurements were carried out for the quantitative elemental analysis of the sand, in order to investigate any possible chemical pollution by heavy metals. For this aim, different indices such as Enrichment Factor (EF), Geoaccumulation Index (I_geo), Contamination Factor (CF) and Pollution Load Index (PLI) were applied to estimate the level of toxicity imposed on the ecosystem by the detected heavy metals. Finally, in order to identify the crystalline mineral components of the investigated sand samples, X-ray Diffraction (XRD) and Micro-Raman Scattering (MRS) measurements were carried out.

Study of Radioactivity in Bajaur Norite Exposed in the Himalayan Tectonic Zone of Northern Pakistan

Radioactivity in Granites of Pakistan systematically increases from south to north. The Ambella Granite found at the northern edge of Pakistan is highly radioactive. Radioactivity measurements made on, so called, Bajaur Granite, located in northern Pakistan, have been found to be lowest among all the granitic rock of the area. In order to find out the exact nature of Bajaur rocks, mineralogical studies were carried on rock chips and powdered samples. The Bajaur Norite contains plagioclase feldspar more than 45% as the chief constituent. Orthopyroxene and clinopyroxene are 27% and 18%. Quartz, biotite, and some opaque minerals are also found in accessory amounts. Bajaur Granite is in fact not a granite but Norite, which is rich in Na-Ca plagioclase series of feldspars. The plagioclase feldspar rich in Na-Ca are low in radioactivity. Moreover, the average gamma activities of 226Ra, 232Th, and 40K (4.98 ± 0.13 Bqkg −1, 4.03 ± 0.31 Bqkg −1, 204.40 ± 4.72 Bqkg −1 and a total of all three radionuclides are 214.00 ± 5.39 Bqkg −1) for Bajaur Norites are found too be much less than the average of the world’s Granites. Indoor and outdoor hazard indices of Bajaur Norite are much below building materials used throughout the world and largely beneath their criterion restrictions. As per radiations’ hazards are concerned, the Bajaur Norite as a building stone may be considered as the safest material available in the area that does not pose any radiological hazard.

Soil mineral analysis and environmental radioactivity in Ghizer, Eastern Hindukush, Pakistan

Distribution of natural and anthropogenic radionuclides (226Ra, 232Th, 137Cs and 40K) was determined in 32 samples from Ghizer, an Eastern Hindukush district at an altitude of 2286 m in Pakistan using high resolution gamma-ray spectrometry. Mineralogical analysis by X-ray diffractometry identified quartz, calcite, albite and anorthite as major phases whereas actinolite, chlorite serpentine and kaolinite as minor phases. The activity concentrations for 226Ra, 232Th, 137Cs and 40K varied from 25.2 ± 1.7 to 145.3 ± 10.1 Bq kg−1, 24.9 ± 1.1 to 197 ± 9 Bq kg−1, 2.03 ± 0.21 to 16.7 ± 1.1 and 252 ± 6 to 1433 ± 35 Bq kg−1, respectively. The samples yielded average radium equivalent activity as 178.4 ± 23.3 Bq kg−1. The majority of the samples revealed external hazard index and representative level index less than one. The average air absorbed dose rate was 91.2 ± 13.6 nGy h−1 corresponding to the annual effective dose rate 111.8 ± 17.4 μSv y−1. These values were higher than the world averages for air absorbed dose rate and outdoor annual effective dose rate. Principal component analysis was applied to obtain distribution pattern within the samples and among the radionuclides.

DETERMINATION OF RA-226, TH-232, K-40 AND CS-137 ACTIVITIES IN SOILS AND BEACH SANDS AND RELATED EXTERNAL GAMMA DOSES IN ARIKLI MINERALIZATION AREA (AYVACIK/TURKEY)

Uranium mineralization areas may jeopardize public health and surrounding natural life. In the current study for radioactivity and geochemical analyses, 43 soil, 5 rock and 10 beach sand samples were collected in and around Arıklı (Ayvacık, Turkey) uranium mineralization area. Radioactivity levels in the soils (up to Ra-226: 629, Th-232: 240, K-40: 3669 Bq/kg) were found higher than the that of beach sands. Besides, radioactivity of the beach sand samples is found at normal levels (avg: Ra-226: 31, Th-232: 31, K-40: 542 Bq/kg) when compared to worldwide average soil. Dose values indicate that the region have ~three times higher average gamma radioactivity than the corresponding world average although measured gamma doses ranged up to 687 nGy/h. The high measured values are related to uranium mineralization, alteration zones, faults and Arıklı tuff.

Assessment of radiation hazards from phosphate rocks, Sibaiya area, central eastern desert, Egypt

The present work used the integrated Carbone γ-ray spectrometric data and HPGe γ-ray spectrometer data to the prospect of radioactive zones at the Sibaiya area, Central Eastern Desert, Egypt. Carbone γ-ray spectrometric survey revealed ten uranium anomalies distributed along the car traverse from west to east direction have values of 240, 104, 44, 34, 150, 124, 232, 132, 60, and 90 ppm, respectively. These significant anomalies are associated mainly with phosphates mines characterized by a substantial increase of eU/eTh and eU/K ratios. Ten phosphate samples were collected from the determining anomalies. They were analyzed using the HPGe detector gamma-ray spectrometer. It was found that the results of radioelement concentrations by carborne survey agree well with that obtained by HPGe. The average activity concentration for the Sibaiya phosphate samples under study is 152.5, 947, and 33.2 Bq/kg against the worldwide accepted limit of 412, 33, and 45 Bq/kg for ⁴⁰K, ²³⁸U, and ²³²Th, respectively. The radium equivalent ranges from 499 to 3484.9 Bq/kg, which is higher than the recommended value 370 Bq/kg. The external hazard's (H_ex) calculated values range from 1.35 to 9.42 mGy/yr, and the internal hazard (H_in) ranges from 2.58 to 18.69. These indexes must be lower than unity to keep the radiation hazard insignificant. The value of the radioactivity level index (Iγ) is found to be more than unity, which varies between 1.68 and 11.63. The dose rate (D_R) ranges from 149.5 to 970 nGy/h, higher than the international mean value of 55 nGy/h. The annual effective dose ranges from 0.18 to 1.19 mSv, which less than unity in almost all values. Meanwhile, the values of activity of ²²⁶Ra ranged from 454 to 3429 Bq/kg and the mean of mass radon exhalation rate (J_m) is 6615 mBq kg^-1 h^-1 which is lower than the worldwide average.

Multivariate statistical approach on distribution of natural and anthropogenic radionuclides and associated radiation indices along the north-western coastline of Aegean Sea, Greece

A comprehensive radiological survey using multivariate statistical analysis was carried out to evaluate the distribution of ⁴⁰K, ²³²Th, ²²⁶Ra, ²³⁵U, and ¹³⁷Cs, and associated radiation indices in beach sand samples of the coastal area of the Aegean Sea. The activity concentration of selected radionuclides was measured and no clue of recent migration of radiocaesium by not only precipitation but also through an indirect way, such as ocean runoff, was found. As part of radiological risk assessment, external radiation hazard index, radium equivalent activity, effective dose, and absorbed dose rate were estimated. Pearson correlation, cluster, and PCA analysis were used by processing observed radiological parameters to determine the correlation between the radiological parameters and locations. Pearson correlation shows a strong association between all parameters and activity of ²²⁶Ra and ²³²Th. A spatial distribution map was provided to a distinct visual representation of the distribution of radionuclide contents in the study area.

ESTIMATION OF RADIOLOGICAL EXPOSURE LEVELS IN A MINING AREA BASED ON 238U, 226Ra, 232Th and 40K ACTIVITY MEASUREMENTS: A CASE STUDY FOR BEYLIKOVA-SIVRIHISAR COMPLEX ORE SITE IN TURKEY

The study estimated the radiological exposure levels in a mining area for miners in the Beylikova-Sivrihisar (Turkey) complex ore site containing 238U, 226Ra and 232Th. Sixty samples were collected from the study area based on a geologic map. The radionuclide activities were measured using a 78.5% efficient n-type HPGe detector. The measured mean activities were 1871 ± 38 Bq kg-1 for 238U, 1749 ± 5 Bq kg-1 for 226Ra, 3467 ± 9 Bq kg-1 for 232Th and 309 ± 2 Bq kg-1 for 40K. From the measured results, the external effective dose was calculated to be max. 3.80 ± 0.03 mSv y-1 (mean: 2.04 ± 0.03 mSv y-1) for inside gallery and max. 7.59 ± 0.05 mSv y-1 (mean: 4.08 ± 0.05 mSv y-1) for outdoor. Additionally, the external exposure index was calculated to be Hex = 33.5 ± 0.2(mean: 18.2 ± 0.3) and internal exposure index to be Hin = 45.9 ± 0.3 (mean: 22.9 ± 0.4). The results indicate that additional radiation protection measures should be taken during the mining process if an opencast mining is implemented in Beylikova complex ore deposit.

ESTIMATION OF RADIOLOGICAL HAZARDS DUE TO NATURAL RADIONUCLIDES FROM THE ROSTERMAN GOLD MINE TAILINGS, LURAMBI, KAKAMEGA, KENYA

Radiological hazards associated with naturally occurring radionuclides in materials from Rosterman gold mine were assessed by analysis of 30 samples. The gamma-ray spectrometric analysis of tailing samples reported an average activity concentration of 263 ± 13, 123 ± 6 and 84 ± 4 Bq kg-1 for 40K, 232Th and 226Ra, respectively. The average absorbed dose rate was 124 ± 6 nGy h-1, while the annual effective dose of 0.4 ± 0.02 mSv y-1 for indoor and 0.3 ± 0.01 mSv y-1 for outdoor were reported. The mean and range of radiological parameters (external and radium equivalent) calculated from the tailing samples were within the permissible limits and hence mining of gold at Rosterman has no significant radiological health implication on the miners and the surrounding population.

Radiological and pollution risk assessments of terrestrial radionuclides and heavy metals in a mineralized zone of the siwalik region (India)

The present study reveals the distribution of terrestrial radionuclides (²²⁶Ra, ²³²Th and ⁴⁰K) and heavy metals (Cr, Ni, Cu, Zn, Pb, Co) from soil samples of Una, Hamirpur and Kangra districts of Himachal Pradesh (India). The ²²⁶Ra, ²³²Th, ⁴⁰K activity concentration in the studied region has been varied from 8 to 3593 Bq kg^-1; 21-370 Bq kg^-116; 62-7130 Bq kg^-1 respectively. High disequilibrium factor (²³⁸U/²²⁶Ra) depicts that uranium constantly migrates from clay oxidizing zone and getting precipitated with enrichment towards south. An attempt has been made to correlate the distribution of these radionuclides and heavy metals with geology and rock type formation of Siwalik region. The concentration of Pb, Zn and Co was found higher than Indian average background value. Multiple radiological and pollution indices have been estimated for proper risk analysis in the studied region. The annual effective dose in studied region is lower than the recommended limit of 1.0 mSv a^-1. The obtained geo-accumulation index and enrichment factor indicated that the sites located in the Hamirpur and Kangra regions were moderately contaminated with Pb and Co. The Nemerow pollution index and contamination security index suggested that almost 45% sites were slightly to moderately polluted. The non-carcinogenic and carcinogenic risks for both children and adults were within acceptable limits.

EFFECTS OF LOCAL BUILDING MATERIALS ON INDOOR GAMMA DOSES AND RELATED RADIOLOGICAL HEALTH RISKS, AYVACIK, ÇANAKKALE/TURKEY

In situ indoor gamma dose rate measurements were held in 79 dwellings by NaI(Tl) scintillation probe connected portable dose rate meter. For the building materials and impurities (nodules), spectrometric gamma analysis was applied by a high-resolution HpGe detector. For Ahmetçe and Nusratlı villages in Ayvacik/Çanakkale (Turkey), the measured in situ indoor gamma dose rates and related indoor annual effective dose equivalents (AEDEin) were 3 and 3.3 times, and indoor excess lifetime cancer risks (ELCRin) were 4.25 and 4.68 times higher than those of the world averages, respectively. The used local rocks were mostly ignimbrite and dacitic-rhyolitic tuffaceous (Arıklı tuff), and wall plasters were made of local soil. The highest in situ indoor gamma dose rates of the region belonged to Nusratlı village due to the intense impurities (nodules) and hydrothermal alterations in Arıklı tuff. Spectrometric gamma results revealed that 40K has an important effect on the indoor gamma doses.

CHARACTERIZATION OF SAND SAMPLES FROM KARACHI BEACHES USING GAMMA SPECTROMETRY AND XRD

Chemical phase and distribution of natural radionuclides (226Ra, 232Th and 40K) were determined for sand samples collected from ten different beaches of Karachi. All samples, except one, were identified with major and minor phases as SiO2 and CaCO3, respectively. The average activity concentrations were 24.9, 25.0 and 239 Bq kg-1 for 226Ra, 232Th and 40K, respectively. Including all samples, the average radium equivalent activity was 79.1 Bq kg-1. The external and internal radiation hazard indices and representative level index were all found below unity. The average air absorbed dose rate at 1 m above the sand due to the natural radionuclides was 18.3 nGy h-1, which was less than the world average for soil. The corresponding annual effective dose rate was 22.4 μSv y-1. It was found that Raeq had positive significant correlation with the amount of quartz present at the beaches.

RADIOMETRIC SURVEY OF THE TYAA RIVER SAND MINE IN KITUI, KENYA

Gamma spectroscopic analyses of sand and rock samples from Tyaa River report an average activity concentration of 33 ± 1, 55 ± 2.8 and 812 ± 40.46 Bqkg-1 for 226Ra, 232Th and 40K, respectively in the sand. A similar analysis of rock samples reveals a mean of 21 ± 2.47, 49 ± 2.47 and 782 ± 39.13 Bqkg-1 for 226Ra, 232Th and 40K, respectively. The absorbed dose rate in rocks averaged 75 ± 3.78 nGyh-1, while in the sand was 86.2 ± 4.31 nGyh-1. The ranges and mean radiological hazard indices (radium equivalent, internal and external) were within the permissible limits and the use of sand and rocks from this mine as construction material pose no health risks. Correlation analysis between the radioactivity in the sand and rocks reveals weak non-linear positive relationships suggesting that they might be from different bedrocks.

Estimation of Natural Radionuclides’ Concentration of the Plutonic Rocks in the Sakarya Zone, Turkey Using Multivariate Statistical Methods

The study aimed to determine the natural radioactivity levels of 226Ra, 232Th, and 40K by the Gamma-Ray spectrometry method, and radiological hazard parameters of the plutonic rocks in the Western and Central Sakarya Zone and to analyze the data using multivariate statistical methods. The average radiological values of samples were determined as 40K (1295.3 Bq kg−1) > 232Th (132.1 Bq kg−1) > 226Ra (119.7 Bq kg−1). According to the skewness values of the distributions of the examined radionuclides, 226Ra (2.1) and 232Th (0.7) seemed to be positively right-skewed while 40K (−0.2) had a negatively right-skewed histogram. On the other hand, the following kurtosis values were calculated for the distributions: 226Ra (5.8 > 3), 232Th (−0.7), and 40K (−0.8). Kolmogorov–Smirnov and Shapiro–Wilk tests were applied to the data to test their normality. Therefore, Spearman’s correlation coefficient method was performed. The radionuclides of 226Ra and 232Th were found to have a positive correlation with radiological hazard parameters of the samples. 2 (two)-related factors identified, and the cumulative value was calculated to be 98.7% on the basis of the Scree Plot. According to the hierarchical cluster analysis, the samples that are grouped with those from Camlik region are prominent. The average radioactivity values of Camlik, Sogukpinar, Karacabey, and Sogut (except for 232Th) regions were detected to be higher than the world averages while the value of 40K was also found to be higher than the average values of various countries in the world.

AT HIGH BACKGROUND RADIATION AREAS THE RELATIONSHIP BETWEEN IN SITU INDOOR GAMMA DOSE RATES AND BUILDING MATERIALS: A CASE STUDY FROM ARIKLI VILLAGE (AYVACIK/ÇANAKKALE/TURKEY)

This study measured in situ indoor gamma dose rates in Arıklı village situated near a uranium mineralisation region, evaluated the risks of radiological health hazards and established a hypothetical relationship between these values and building materials using statistical tools. Eberline brand portable type ESP-2 model Na (I) scintillation probe connected detector was used for the measurements in 45 dwellings. Statistics revealed two groups. The first group consists of the dwellings made of bricks or mixed materials both plastered by cement, while the second group represented the dwellings made of Arıklı tuff plastered with soil (modified Arıklı tuff) or cement. For the first and second groups, respectively, the medians of the indoor gamma dose rates were 188.79 and 261.87 nGy/h; for indoor Annual Effective Dose Equivalents (AEDEin) they were 0.93 and 1.28 mSv/h; and for Excess Lifetime Cancer Risks (ELCRin) they were 3.69 and 5.12, respectively. All the values were higher than those of the world averages.

Data on natural radioactivity and associated radiation hazards in coastal sediment of Chennai Coast, Tamilnadu, India using gamma ray spectrometry

This article contains data on the activity concentration of natural radionuclides in coastal sediment samples collected from Pulicat Lake to Vadanemmeli, East coast of Tamil Nadu using NaI(Tl) detector based γ-spectrometry. As marine sediments are found to be the repository of many radioactive pollutants, studied the objectives like (i) determine natural radionuclide activity concentrations in sediment samples in and around Chennai coast (ii) evaluate the radiological hazards due to natural radioactivity associated with coastal sediments and (iii) identify areas which may be radiological hazardous for the public along the study area. The average activity concentration of ²³⁸U, ²³²Th and ⁴⁰K in the present study is lower than world median value. The radiological hazard indices such as External hazard index (H_ex) and Gamma representative level index, (Iγ) were evaluated to assess radiation hazard associated with the sediments. The simulated results show sediments do not pose any significant radiation hazards due to concentration of natural radionuclides.

Natural radioactivity in granites and gneisses of the Opava Mountains (Poland): a comparison between laboratory and in situ measurements

The natural radioactivities of five characteristic igneous rocks of the eastern foreland of the Opava Mountains (Eastern Sudetes, Poland), obtained in the laboratory and under in situ conditions, are presented. The activity concentrations of ²³²Th, ²³⁸U, and ⁴⁰K were measured using an HPGe gamma-ray spectrometry system. The ranges of the activity concentrations of ²³²Th were 7–71 Bq kg⁻¹ in the laboratory and 6–68 Bq kg⁻¹ for the in situ measurements. For ²³⁸U, the ranges of the activity concentrations were 5–52 Bq kg⁻¹ in the laboratory and 9–48 Bq kg⁻¹ for the in situ measurements, and for ⁴⁰K, the ranges were 520–1560 Bq kg⁻¹ in the laboratory and 537–1700 Bq kg⁻¹ for the in situ measurements. These determined activity concentrations were compared with the average activity concentrations of the radionuclides in similar types of rocks and with data from the Sudetes available in the literature. No significant differences were found between the in situ and laboratory measurements.

Hazardous parameters associated with natural radioactivity exposure from black sand

Black sand samples collected from Baltim beaches (Kafr El-Sheikh governorate) in Egypt on the Mediterranean Sea shore were analyzed radiometrically and evaluated using a nondestructive gamma ray spectroscopic techniques. The natural radionuclides of ²²⁶Ra, ²³²Th and ⁴⁰K in the black sand samples were identified and quantified. It is found that the activity concentrations for ²²⁶Ra, ²³²Th and ⁴⁰K in different eleven sites (S1S11) were found within the ranges of 28-322, 91-308 and 81-339 Bq/kg, respectively. Moreover, different radiological hazardous parameters (absorbed dose rate, annual effective dose equivalent, radium activity, annual gonadal dose equivalent and excess lifetime cancer risk) were calculated. The results show that these values are greater than the permissible values due to increasing the activity concentrations of the primordial radionuclides ²²⁶Ra, ²³²Th and ⁴⁰K. The dose rate for radiation emitted at 1 m from the surface of land was measured directly and the results shown that all sites emit radiation doses more than the international permissible value (57 nGy/h) especially at three sites which around 340 nGy/h. These values are important to establish baseline levels of this environmental radioactivity to detect any upcoming change for the local population and resorts people. The relatively high dose rate will be considered as a spa for the physical therapy such as treatment of some skin diseases and rheumatoid.

Environmental implications and spatial distribution of natural radionuclides and heavy metals in sediments from four harbours in the Egyptian Red Sea coast

Measurements of natural radionuclides concentrations (²²⁶Ra, ²³²Th and ⁴⁰K) in sediments collected from sea, rivers or ocean is significant to protect the sea water ecosystem and to human health from radiation. Thirty-three sample of sediment have been collected from four ports in the Red Sea coast, Egypt for investigation by gamma-ray spectrometer using NaI(Tl) detector. The average and range activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K were 26(5-58), 19(4-33) and 458(16-2665)Bqkg^-1 in Quseir Harbour, 30(14-53), 20(14-34) and 430(378-511)Bqkg^-1 in Abu-Tartour Harbour. However, the average and range activity concentrations were 23(14-35), 21(15-32), and 602(327-821)Bqkg^-1 in Touristic Harbour and 14(5-26), 13(2-23) and 489(36-950)Bqkg^-1 in Hurghada harbour. These results were compared with reported ranges in the literature from other location in the world. The radiation hazard parameters; radium equivalent activity annual dose, external hazard were also calculated and compared with the recommended levels by UNSCEAR reports. Eight heavy metals (Fe, Mn, Ni, Co, Zn, Cu, Pb and Cd) have been measured and analyzed by atomic absorption spectrometer. The concentration for the investigated heavy metals overtakes the allowable limits recommended by the Canadian Environmental Quality Guidelines. Because there are no existing databases for the natural radioactivity in the sediment samples from Egyptian Red Sea ports, our results are a start to establishing a database for Red Sea harbours environment.