Assessment of radiological hazard parameters due to natural radioactivity in soils from granite-rich regions in Kütahya Province, Turkey

Assessment of radiological hazards of soils from the city of Bitola (Macedonia) and its environs

To establish the radioactivity level of soils and assess the associated radiological impact on residents, 58 samples from the town of Bitola and its environs were collected. After conducting gross alpha and gross beta measurements with a gas-flow proportional counter as a preliminary screening test, subsequent gamma-spectrometry measurements reveal the presence of 40K, 226Ra, 232Th, and 137Cs in the soil samples as radionuclides with the highest impact. The absorbed gamma dose rate, the annual effective dose, radium equivalent activity, external hazard index, gamma index, excess lifetime cancer risk, and annual gonadal dose were calculated using the obtained activity concentrations of the radionuclides. Upon comparison with similar studies conducted in the Balkan countries, the obtained results for radiation hazard indices were found to be the highest in the region. Coloured maps were generated to visually represent the spatial distribution of the absorbed gamma dose rate in air and annual effective dose, clearly indicating the combined influence of geology and human activities, including the nearby thermoelectric power plant operation.

Investigation of natural and artificial radioactivity levels in travertines of the Cappadocia region in Turkey

This study determined natural and artificial radionuclide concentrations to evaluate natural radioactivity and health risk levels of nine travertines in the Yaprakhisar and Balkayası regions in Turkey. The samples coded B1-M, B2, B5, B7, B8, and B10 represent waste derived from the Yaprakhisar travertines, as well as samples T5-M, T12, and Z1 travertines derived from Balkayası. The levels of natural and artificial radionuclide concentrations (232Th, 40K, and 137Cs) were measured using a high-purity germanium (HpGe) detector system. The travertine activity ranged from 2.09 to 12.07 Bq kg-1 for 232Th, 4.21 to 13.41 Bq kg-1 for 40K, and 0.42-3.26 Bq kg-1 for 137Cs. The results showed that the activity concentration values for 232Th, 40K, and 137Cs were coherent with the travertine analysis results in the UNSCEAR, 2000; 2008 publications. The values obtained were lower than the average values in the UNSEAR reports. The radiological hazard parameters calculated in this study were absorbed gamma dose rate (D), radium equivalent activity (Raeq), annual gonadal dose equivalent (AGDE), exposure dose (ER), total annual effective dose (AEDEtotal), excess lifetime cancer risk (ELCRtotal), gamma representative level (GRL), internal hazard index (Hin) and external hazard index (Hex).

Assessment of radiological indices and physiochemical characterization of sediments in Chashma Lake, Pakistan

Twenty surface sediment samples were gathered from Chasma Lake, deciding the radionuclides 137Cs, 226Ra, 228Ra, 232Th, and 40K and their associated hazard indices. The deliberate radionuclide activities of present research have been contrasted with earlier research, and acquired outcomes in the present study are found below the results in the world. The radiation hazard indices following the presence of natural radionuclides in sediment samples were estimated, and the results assigned the values of all the determined radiological indices found inside the worldwide suggested limits. It was concluded from the current review that the sediment of Chashma Lake is safe for construction and agriculture and does not make radiation dangerous to the nearby local area of the lake.

Natural and artificial radioactive pollution in sediment and soil samples of the Bosphorus, Istanbul

This study focused on the determination of natural (²³⁸U, ²³²Th, and ⁴⁰K) and artificial (¹³⁷Cs) radionuclide concentrations both in 55 sediment samples collected from various depths in the Bosphorus and 5 soil samples from the coastline of the Bosphorus, Istanbul, using gamma-ray spectrometry with an HPGe detector. The mean activity concentrations of natural ²³⁸U, ²³²Th, and ⁴⁰K and anthropogenic ¹³⁷Cs were determined to be 11.41 ± 0.21 Bq kg^-1, 6.87 ± 0.16 Bq kg^-1, 369.61 ± 3.41 Bq kg^-1, and 6.54 ± 0.11 Bq kg^-1, respectively, in the sediment samples. The average activity concentrations of ²³⁸U, ²³²Th, ⁴⁰K, and ¹³⁷Cs radionuclides in the soil samples were also measured to be 11.65 ± 0.18 Bq kg^-1, 9.55 ± 0.15 Bq kg^-1, 369.43 ± 3.09 Bq kg^-1, and 4.57 ± 0.09 Bq kg^-1, respectively. Radiological contour maps based on the activity concentrations of natural and artificial radionuclides in the sediment samples for the Bosphorus, Istanbul, were created. The total annual effective doses due to soil samples were calculated to be 34.58 μSv y^-1.

Radiation doses due to smoking different types of tobacco leaves grown in Turkey

The activity concentrations of ²³⁸U, ²³²Th, ⁴⁰ K and ¹³⁷Cs radionuclides in 25 samples of tobacco leaves grown in Turkey have been measured using a high purity co-axial germanium detector. The measured activity concentrations for ²³⁸U ranged from 3.6 to 22.5 Bq kg^-1 with an average of 9.8 Bq kg^-1, for ²³²Th from 0.8 to 11.0 Bq kg^-1 with an average of 2.4 Bq kg^-1, and for ⁴⁰ K from 360.3 to 1,479.5 Bq kg^-1 with an average of 810.0 Bq kg^-1. The concentrations of ¹³⁷Cs, the residue of fallout from the Chernobyl reactor accident, were found to range from 0.2 to 2.1 Bq kg^-1 with an average of 0.5 Bq kg^-1. The results indicate that the average activity concentrations of ²³⁸U and ²³²Th lie within the range of measured values worldwide, whereas for ⁴⁰ K the average was found to be higher. The average annual effective radiation doses from the inhalation of the corresponding tobacco smoke by an adult smoking 20 cigarettes per day was deduced to be 93.3 μSv y^-1 for ²³⁸U, 193.2 μSv y^-1 for ²³²Th, 5.6 μSv y^-1 for ⁴⁰ K, and 292.1 μSv y^-1 in total. The average annual effective dose from ¹³⁷Cs was calculated to be 8.5 nSv y^-1. The resulting average annual effective radiation doses of 0.3 mSv due to the inhalation of natural radiation sources in tobacco were compared with studies worldwide and found much smaller than the worldwide average effective dose of 1.26 mSv. It is concluded that smoking may contribute a non-negligible fraction to the annual effective dose depending on cigarette consumption and activity concentration in tobacco. This study is the first in which natural and anthropogenic radioactivity in tobacco in Turkey was measured. Therefore, it is considered as a baseline study. Further studies are needed to investigate the role of tobacco refinement in the observed reduction of ²³⁸U concentration of refined tobacco.

Measurement of Natural Radioactivity and Assessment of Radiological Hazard Indices of Soil Over the Lithologic Units in Ile-Ife Area, South-West Nigeria

The distribution of natural radioactivity levels of ²³⁸U, ²³²Th, and ⁴⁰K in soils overlying the 3 lithologic units within Obafemi Awolowo University, Ile-Ife, Nigeria was investigated to characterize the gamma radiation dose distribution over the lithologies and to assess the radiation hazard due to the natural radionuclides. A thallium-doped cesium iodide detector was employed to determine the activity concentrations of ²³⁸U, ²³²Th, and ⁴⁰K in 21 soil samples. The respective average concentrations of the 3 radionuclides are 37.7, 3.2, and 245.6 Bq kg^-1 for granite gneiss, 31.9, 2.8, and 241.1 Bq kg^-1 for banded gneiss, and 21.1, 1.7, and 196.7 Bq kg^-1 for mica schist. The average concentration of ²³⁸U in granite gneiss lithology exceeds the world average value. The evaluated values of radiation hazard parameters including average absorbed dose rate, outdoor annual effective dose and external hazard index are below the recommended limits. The spatial distribution of the radiation hazard parameters evaluated over the lithologies has been delineated. The highest average cancer risk of 1.15 per 10 000 population was obtained for the study area within the soil overlying the banded gneiss lithology. Generally, the radiation hazard from the soils in study area poses no significant health hazard.

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.

Characterization of radionuclide activity concentrations and lifetime cancer risk due to particulate matter in the Singrauli Coalfield, India

In this study, the activities of ⁴⁰K, ²¹⁰Pb, ²³²Th, ²³⁴U, ²³⁵U, and ²³⁸U in size-segregated particulate matter (PM) were measured in the Singrauli Coalfield, India. Different isotopic compositions were found relative to natural uranium ratios. The radioactivity concentration ratios in different PM sizes [PM_2.5, PM₁₀, and suspended particulate matter (SPM)] suggested that anthropogenic sources affected the uranium isotopic compositions in the area. A different isotopic composition from the natural uranium composition was found. The correlation coefficients between the measured isotopes (⁴⁰K, ²¹⁰Pb, ²³²Th, ²³⁴U, ²³⁵U, and ²³⁸U) and meteorological factors were calculated. PM emissions were affected by the meteorological conditions, which in turn, influenced the U and Th concentrations in PM. The ²³²Th/²³⁸U activity ratio in particulate matter was between 0.20 and 1.54 with an average value of 0.9 ± 0.5, 0.2 to 1.1 (0.8 ± 0.7), and 0.2 to 1.2 with an average value of 0.8 ± 0.8 in PM_2.5, PM₁₀, and SPM, respectively. These range were quite different from the average crustal ratio of 3.5, indicating that the ²³⁸U concentrations were elevated in this region relative to Th. However, compared with Th, the dose contribution of U to the public was negligible. The average effective dose in public owing to inhalation of natural radioactive ⁴⁰K, ²¹⁰Pb, ²³²Th, and ²³⁴U, ²³⁵U, and ²³⁸U in the atmosphere was between 0.03 and 327 nSv year^-1. These doses associated with the inhalation of particulate matter were lower than world airborne reference value as reported by UNSCEAR (2000a). Graphical abstract.