Natural Radioactivity Concentrations Research Articles

Assessment of natural radioactivity levels and hazard indicators in Tarakeshwor Municipality, Nepal through in-situ technique and multivariate analysis

The evaluation of primordial radionuclide concentrations in rapidly urbanized and concrete-laden areas through the importation of construction materials from various regions of Nepal is both important and essential. This study utilized a portable gamma-ray spectrometer (PGIS 2) to analyze the distribution of three natural radionuclides: uranium (238U), thorium (232Th), and potassium (40K) in Tarakeshwor Municipality, Kathmandu, Nepal. The measured dose rates ranged from 70.22 nSv hr−1 to 163.66 nSv hr−1, with an average of 124.65±20.29 nSv hr−1, surpassing the global average of 59 nSv hr−1. The activity concentrations of 40K, 238U, and 232Th exceeded global averages, indicating relatively higher natural radioactivity concentrations in the region. Specifically, the average values for 40K, 238U, and 232Th were 935.26±172.30 Bq kg−1, 80.47±15.53 Bq kg−1, and 80.44±18.58 Bq kg−1, respectively. The calculated radium equivalent (Raeq) ranged from 132.26 to 351.22 Bq kg−1, and the annual gonadal equivalent dose (AGED) varied from 372.61 to 1028.81 μSv yr−1. The annual effective dose rates for indoor and outdoor environments were 0.54±0.09 mSv yr−1 and 0.15±0.03 mSv yr−1, respectively, both exceeding the global average. The representative level index (RLI) within the study area averaged 1.96±0.32, indicating an elevated radiation risk. The excess lifetime cancer risk (ELCR) values for outdoor and indoor environments were 0.52×10−3 ±0.09 ×10−3 and 1.87 ×10−3 ±0.31×10−3, respectively, surpassing the world average. Additionally, external hazard indices (Hex) ranged from 0.36 to 0.59, while internal hazard indices (Hin) ranged from 0.38 to 1.20, both indicating values higher than UNSCEAR recommendations. These findings underscore the necessity for further experimental analysis employing ex-situ equipment. The data generated in this study can provide a valuable baseline for future assessments and interventions in radiation risk management guidelines within the country.

Risk Assessment of Natural Radionuclides and Trace Elements of Industrial Activities in Suez Bay

ABSTRACT The study aims to assess the marine environmental hazards resulting from some industrial activities areas being found at the Suez Bay. The survey was done to select five industrial locations along the studied areas where different water and sediment samples were collected during September 2020. The study methods showed that different concentrations were measured in the collected water and sediment samples, such as; Al, Fe, Mn, Hg, Cd, Cr, Co, Mo, V, Pb, Ni, Cu, Zn, where the digested samples were measured by using Inductively Coupled Argon Plasma spectroscopy (ICAP 6500 Duo), while the natural radioactivity concentrations of the selected radio-nuclides such as 238U, 226Ra, 232Th, 40K, were measured in both water and sediments samples by using Hyper germanium detector, as the radiological risk assessment of different samples was detected by using ERICA modeling software. The study results showed that the concentrations of the measured trace elements in the selected five industrial sites were slightly higher than the standard limits, while the measured radioactivity concentrations of the selected radio-nuclides in both water and sediment samples were below the standard limits. The results showed that the calculated distribution coefficient of the selected trace elements was (Kd Metal Pollution Index < 3), which indicated that the measured trace elements were more dissolved in the aqueous than the sediment medium. The study used the mean probable effect Level (m-PEL-Q) for estimating the metal concentration hazards in the sediment samples at the selected sites, where these values were ranged from 0.04 to 0.1, indicating that the combined concentration effects for these metals were caused 9% toxic probability. The study showed that both the calculated quotient risk (QR) and dose rate values of the marine organisms which were being calculated by the ERICA model were below the recommended limits.

Activity concentration of NORM at reclaimed ex-coal mines in South Sumatra, Indonesia

Unbeknownst to us, natural radiation is in close proximity to human existence. Post-mining practices can generate naturally occurring radionuclides that have the potential to cause radiological effects on human health. This study utilized soil samples obtained from ex-mining reclamation land in Banko Barat, South Sumatra Province, to assess the concentration of natural radioactivity and the corresponding radiation dose. Eight composite soil samples were collected from reclaimed land. The samples underwent processing and analysis through gamma spectrometry in order to ascertain the activity concentration of the radionuclides 226Ra, 232Th, and 40K. The RESRAD-ONSITE 7.2 software utilizes the activity concentration of soil samples as an input parameter to accurately predict the dose rate for workers. The projected dose rate was determined by considering four routes of exposure: external gamma radiation, inhalation, radon, and ingestion of soil. The measured activity values of soil samples from reclamation land for 226Ra ranged from 25.6704 ± 0.5082 to 58.8555 ± 0.6917 Bq/kg. The activity values for 232Th ranged from 30.5546 ± 0.1757 to 42.53020.3004 Bq/kg. Lastly, the activity values for 40K ranged from 533.902 ± 6.4023 to 988.081 ± 9.6948 Bq/kg. The total effective dose rate measured in the reclaimed land falls between 0.08673 and 0.1469 millisieverts per year. The value does not surpass the maximum limit set by BAPETEN, which is one mSv/year. Therefore, no additional protective measures are required for workers.

Assessment of Radiation Dose Associated with Background Radionuclides in Quarry Soil at Dawakin-Kudu LGA Kano, Nigeria

Naturally occurring radioactive materials (NORMs) are present in different concentrations in the environment as well as quarry depending on the geological formation of the soil. The assessment of any release of radioactivity into the environment is crucial for safeguarding public health, particularly when this radioactivity has the potential to enter the food chain. The quarry located in Dawakin-Kudu Kano has the potential to exhibit elevated levels of natural radioactivity due to intense mining operations. This study presents the assessment of activity concentration in quarry soil at Dawakin-Kudu with a focus on the transfer mechanism from soil to plant. Soil samples were gathered from a quarry site and farmlands situated around the quarry at Dawakin-kudu, plant samples were also collected from the same farmlands and were all analyzed for natural radioactivity, specifically for 226Ra,232Th, and 40K. The gamma-ray spectrometry method, coupled with the Sodium thallium Iodide NaI (Tl) detector was used to measure the activity concentrations of 226Ra,232Th, and 40K. Activity concentrations of natural radioactivity in soil were generally higher than those recorded in plants. The mean activity concentration of the radionuclides in soil ranges from Highest-to-Lowest values as follows 226Ra: 65.24±1.92 Bqkg-1 – 42.41±1.73 Bqkg-1, 232Th: 182.71±1.44 Bqkg-1 – 114.61±1.25 Bqkg-1, 40K: 597.51±3.81 Bqkg-1 – 321.93±3.55 Bqkg-1. The radiological hazard indices were all determined to assess the radiation hazard of the quarry soil. The radionuclides transfer factor showed a higher value for 40K in the order 40K&gt;232Th &gt;226Ra, this implies high bioconcentration of 40K in plants. The findings suggest that consuming plants grown around the quarry location over an extended period could pose substantial health threats to the public. Consequently, the study area may not be safe for residents in the long run, emphasizing the necessity for continuous monitoring of radioactivity concentrations to mitigate the environmental health implications of accumulated...

Determination of Natural Radioactive Concentration Levels in a Selection of Halfaya Oil Drilling Wells in Maysan Governorate, Iraq

Determination of Natural Radioactive Concentration Levels in a Selection of Halfaya Oil Drilling Wells in Maysan Governorate, Iraq

Natural radioactivity in Turkish foodstuff consumed in Iraq

Different levels of natural radionuclides were found in food items, and these variations were attributed to factors such as background radiation levels, climate, and agricultural practices. These radionuclides are recognized as the primary contributors to the internal radiation exposure experienced by humans. Among the natural radionuclides, the ones of most significant concern for radiation protection are those belonging to the decay series of 238U and 232Th, as well as 40K. The concentration of natural radioactivity in several Turkish food products accessible on the Iraqi market was measured using a NaI (Tl) gamma-ray spectroscopy detector. The measured concentrations in unit Bq kg−1 of 238U, 232Th, and 40K ranged from 3.2 to 19, 1.2 to 24.1, and 22.5 to 690.9, respectively. The study also calculated the annual effective dose for individuals who consume such foods. The annual internal dose from ingesting studied radionuclides found in foodstuff was calculated to be 0.274 ± 0.05 mSv/y. Notably, this calculated dose falls below the worldwide value of 0.32 mSv/y established for the general public.

Investigating radiation profiles and conducting risk assessment for ecological and environmental components on Vaan and Koswari islands in the Tuticorin group of islands, India.

Natural radioactive concentration assessment was conducted on sediment, water, and biota obtained on Vaan and Koswari islands in the Tuticorin group of islands, Tamil Nadu, India. For biotic and abiotic components, radiation profiles such as gross alpha, beta, primordial radionuclide, polonium, and lead analyses were performed. The gross α and β range from BDL to 15.18 ± 1.7Bq/kg and 40.43 ± 4.9Bq/kg to 105.12 ± 11.7Bq/kg, respectively. Primordial radionuclides were analyzed using Nal(TI)-based scintillator with PC-MCA, and the concentrations ranged from 13.43 ± 3.3Bq/kg to 30.97 ± 9.6Bq/kg with a mean of 21.31 ± 2.7Bq/kg for 238U; for 232Th, the values ranged from 11.09 ± 2.6Bq/kg to 33.55 ± 9.5Bq/kg with an average value of 23.89 ± 3.7Bq/kg; and for 40K, the values are 93.33 ± 27.3Bq/kg to 219.91 ± 39.6Bq/kg with an average value of 148.27 ± 21.7Bq/kg. The present study values are lesser than the world average values. 210Po and 210Pb concentrations with an average value were determined to be 33.13Bq/L and 16.56Bq/L, 47.55Bq/L and 22.37Bq/L in the water sample, and 50.437Bq kg1 and 62.012Bq kg1, 46.99Bq/kg and 58.625Bq/kg in sediments of Vaan island and Koswari island. The concentrations of 210Po and 210Pb of Pogonias cromis were 19.27 ± 1.5Bq/kg and 8.27 ± 1.01Bq/kg, Belonidae 28.54 ± 2.4Bq/kg and 18.32 ± 2.3Bq/kg, Lepisosteidae 18.68 ± 1.4Bq/kg and 11.17 ± 1.8Bq/kg. The committed effective dosage was determined to be 35.74-54.61 µSv/y for 210Po and 25.39-56.25 µSv/y for 210Pb, in which the 210Pb value is lower; however, the 210Po value is higher than the global average value. The annual committed effective dosage as well as the radiological hazard indices were assessed and found to be much below the global average and the recommended limit, respectively. This research provides an extensive analysis of natural background radiation and establishes a baseline report on the radiological profile of biotic and abiotic factors in the Tuticorin group of islands, namely Vaan and Koswari, in Tamil Nadu, India.

ASSESSMENT OF KARAMUSTAFA GOLD-BEARING Zn-Pb MINE (GÜMÜŞHANE, TÜRKİYE) AREA IN TERMS OF NATURAL AND ARTIFICIAL RADIOACTIVITY

This study aimed to assess the environmental effects of natural and artificial radioactivity contents, especially in the context of medical geology of base metal-containing mineral deposits. In the study, artificial/anthropogenic (137Cs) and natural (226Ra, 232Th and 40K) radioactivity levels in the soil of the Karamustafa gold-bearing Zn-Pb-(±Cu) mining area, one of the important mines of Gümüşhane (NE Türkiye), were determined and evaluated. In order to determine the natural and artificial radioactivity of the mining area, 9 soil samples were collected from different parts of the field, taking into account the geological and alteration characteristics of the field. 232Th, 226Ra and 40K activities of the samples prepared according to the relevant laboratory procedures were determined by the gamma-ray spectrometry, and the artificial radioactivity values of 137Cs were also measured. As a result of the study, it was determined that the 40K and 226Ra average activities of the Karamustafa gold-bearing Zn-Pb-(±Cu) mining area exceeded the world averages in most sampling points, while the 232Th activities were above the world averages at some sampling points. It has been determined that the artificial/human-derived 137Cs radioisotope values in the field are remarkably high. Considering the major radio indices calculated for the field, it was determined that the absorbed dose rate and annual effective dose rate indices of the mine site exceeded the relevant threshold values. When all the data obtained from the field were evaluated together, it was concluded that the mine field needed detailed study in the context of radiation risk.

Natural radioactivity content and elemental composition in different grain sizes of Mamallapuram beach sand

Measurement of natural radioactivity content as well as elemental composition in three different grain sizes (600–425 μm, 425–250 μm and 250–125 μm) of Mamallapuram beach sand, obtained from three sites, have been undertaken using gamma ray spectroscopy and SEM-EDX respectively. 238 U and 232Th activities are higher at the lowest grain size sands (250–125 μm); 40 K activity is seen, only in those samples, where 238 U and 232Th activities are comparatively lesser. In SEM-EDX analysis of the beach sand samples, fourteen elements have been identified. Besides Oxygen (39.06 %) and Silicon (24.59 %), other elements identified, which are more than 1 % are, Iron (13.46 %), Titanium (10.75 %), aluminum (5.22 %), calcium (1.46 %), magnesium (1.28 %) and Potassium (1.28 %). Six elements in trace levels have also been observed viz., Mn (0.68 %), Ni (0.38 %), V (0.36 %), Cr (0.35 %), Zn (0.35 %) and Co (0.32%).

Measurement of transfer factors from soil-to-plant/food crop of Naturally Occurring Radionuclide Materials (NORMs) in Nigeria: a review

One of the most crucial factors in the environmental safety assessment for the local and global communities, situated either in normal background areas or around nuclear facilities, is the uptake of radionuclides from soil by plants, which is typically stated as soil-to-plant Transfer Factor (TF) or Transfer Coefficient (TC). Such a metric, which can be defined as the ratio of radioactivity unit per dry crop mass to that of unit per dry soil mass, is necessary for environmental transfer models, which help to estimate the radionuclide concentrations in agricultural crops and calculate the dose exposure to people. In this article, a number of research studies conducted by scholars in Nigeria, published in both national and international journals, were compiled and reviewed for the purpose of providing an integrated and synthesized overview of the current state of knowledge on NORMs’ transfer factors in Nigeria. The activity concentrations of 40K, 226Ra, 228Ra, 232Th and 238U were measured by different research groups using gamma ray spectrometry coupled with either NaI(Tl) or HPGe detector. The activity concentrations of natural radioactivity in soils samples were generally higher than the values recorded in plant and food crop samples in almost all the research studies considered in the review. About 79% of the values of soil-to-plant transfer factor of 40K in all the studies under review were greater than the recommended value, while the values of transfer factors reported for 232Th and 238U were all greater than the recommended values.

Natural radioactivity concentration measurements in shrimp and sea bass samples from the Mexican Pacific Ocean and the Gulf of Mexico

The radioactivity concentration for shrimp and sea bass retrieved from the Mexican Pacific Ocean and the Gulf of Mexico is reported in this work. The activity of 40K and 208Tl was determined with gamma spectroscopy using a High Purity Germanium detector. Overall, the radioactivity concentration of samples from the Mexican Pacific Ocean is higher than from the Gulf of Mexico. The 40K concentration measured for shrimp is 575 ± 14 Bq/kg (Pacific) and 443 ± 10 Bq/kg (Gulf), while the activity for sea bass is 753 ± 18 Bq/kg (Pacific) and 502 ± 14 Bq/kg (Gulf). Similarly, the measured concentration of 208Tl for shrimp and sea bass is 0.75 ± 0.03 and 1.09 ± 0.05 Bq/kg (Pacific), respectively, and 0.51 ± 0.02 and 0.85 ± 0.04 Bq/kg (Gulf), respectively. No other natural radionuclides or radiation contaminants were observed with significant activity. This is the first comparison of radioactivity concentration in fish and shellfish between the two main Mexican marine ecosystems.

Development of a Pre-Diagnosis Procedure for the Evaluation of Indoor Radon Potential in Buildings

Indoor radon accumulation is considered the main source of human exposure to ionizing radiation. Depending on the average radon level, indoor long-term exposure can significantly increase the risk of lung cancer onset. The publication of international regulations on the protection of human health the exposure of ionizing radiation, defining threshold values over whom health consequences for occupants could be expected, led to the control and testing of radon levels in workplaces and premises using multiple techniques and approaches. In particular, since the main source of radon is soil, many efforts have been done for the redaction of maps of the geogenic potential risk, as well as the definition of proper measurement standards and techniques for indoor monitoring. Radon maps, based on geology and measurements of radon and/ or the natural radioactive content in the soil, constitute an evaluable tool for decision-making authorities in radon policies giving the possibility to characterize areas for radon risk where indoor radon measurements are not available. But, of course, they are not completely descriptive of the potential risk, so indoor monitoring in buildings is also required. The correct design of an indoor monitoring campaign is a crucial topic.. Scientific literature has largely demonstrated that many site-specific features influence the accumulation process, as well as most building materials represent a significant source, after the soil. The preliminary complete investigation in buildings should be properly defined since radiation safety in a situation of radon exposure completely ensured during the building's construction and maintenance phases as well as during the selling/rental ones. So, the aim of this work is to put the basis for the development of a pre-diagnosis procedure as a tool for the screening of buildings susceptible to high indoor radon activity concentrations. The work represents a very early stage of implementation of a qualitative method for the design of a measurement campaign for the indoor radon assessment. A pre-evaluation selection of the variables that play a leading role in the accumulation process is presented. A prior survey, based on evidence in scientific literature, was done to identify all relevant characteristics that most affect indoor radon levels, mainly concerning local geology, building features, ventilation, and occupancy factors. The selected parameters, classified into levels according to defined indicators and then combined, allow a more refined sample selection for measurements campaign in the indoor radon assessment process. Future development will be oriented to the validation of case studies and the implementation of the procedure in a software environment which will be the first tool available to systematize and regulate the radon monitoring process for short-term decision-making.

Natural and Artificial Radioactivity Concentrations and Health Risks due to Radionuclides in the Soil of Nevşehir (Cappadocia)

Natural and artificial radionuclides in the surface soil samples collected from the Nevşehir (Cappadocia) region were analyzed using gamma spectrometry employing an HPGe detector. Activity concentrations of 226Ra, 232Th, and 40K range from 58.31 to 77.40 Bq kg−1, 60.56 to 90.97 Bq kg-1, and 796.42 to 1142.8 Bq kg-1, respectively. The values indicate that the activity concentrations of the natural radionuclides in the soil samples were higher than the world average. Since Turkey is a country greatly affected by the Chernobyl accident, 137Cs activity concentration was measured to determine whether its effect continues. The activity concentration of 137Cs ranges from Minimum Detectable Activity (MDA) to 6.88 Bq kg−1. In addition, the radium equivalent activity, the absorbed dose rate, the annual effective dose equivalent, and the excess lifetime cancer risk parameters were calculated to determine the radiological effect of natural and artificial radionuclides on the population in the study area. All values except the radium equivalent activity were found to be above the world average.

Assessment Of Natural Radioactivity Concentration and Associated Radiological Hazards of Commercial Wall Paints and Plaster of Paris Cements Commonly used in Nigeria

Assessment Of Natural Radioactivity Concentration and Associated Radiological Hazards of Commercial Wall Paints and Plaster of Paris Cements Commonly used in Nigeria

The presence of NORMs and toxic heavy metals in talcum baby powder

Baby talcum powder is one of the popular baby care products used for keeping the baby's skin dry and preventing diaper rash. In the past few years, there has been a growing concern on the presence of toxic heavy metals within the baby talcum powder due to its potential threat to human health and environmental effects. However, its natural radioactivity content is much less considered where it may pose similar health risks to the consumers. The present study examines the radioactivity and heavy metals concentration towards the commonly used baby powders in Malaysia, including Pureen, Johnson's, Carrie Junior and Zwitsal, utilizing the High Purity Germanium (HPGe) gamma-ray spectrometry and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Individual health risk assessment has been conducted through the estimation of absorbed dose rate due to the exposure of ionizing radiation from the three long-lived primordial radionuclides of 226Ra, 228Ra and 40K through the usage of baby powders. The assessment revealed that an individual might be exposed to an average radiation dose rate of 0.518 pGy h−1, albeit lower than the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) reference exposure dose limit of 59 nGy h−1 for terrestrial radionuclides. In regards to heavy metals toxicity, all baby powders are within the permissible limits of heavy metals concentration recommended by the National Pharmaceuticals Regulatory Agency (NPRA), ASEAN Cosmetic Scientific Body (ACSB) and the United States Food and Drug Administration (FDA) except for Ni where its concentrations were slightly above the permissible value of 0.6 ppm outlined by FDA. Prolonged use of baby powders contaminated with such heavy metal may pose a significant risk to human health and the environment due to its toxic metal loading. These results emphasize the need for periodic monitoring and quality control of baby powders to ensure they meet safety standards and minimize potential risks to human health and the environment.

Evaluation of radioactivity levels and radiological hazards of some endemic plants used as medicine in Ankara, Turkey

In this study, natural radioactivity levels (226Ra, 232Th, and 4 K) of some medicinal plant samples with known anti-oxidative properties, which are frequently consumed by animals and humans, were obtained from Ankara province and its surroundings (Mamak, Kızılcahamam, Beypazarı, Kahramankazan, and Polatlı districts) were determined using a thallium-doped sodium iodide NaI(Tl) gamma spectrometry. By using the determined natural radioactivity concentrations in the collected plant samples, the number of radiological doses that people could be exposed by consuming these plants was calculated. As a result of the study, 226Ra, 232Th, and 4 K radioactivity concentration ranges of the plant samples were found be 14.69 ± 1.27–59.08 ± 3.12 Bq kg−1, 1.78 ± 0.04–50.05 ± 2.76 Bq kg−1 and 207.24 ± 34.09–826.13 ± 25.40 Bq kg−1, respectively. The highest 226Ra, 232Th, and 4 K activity concentrations were measured in Astragalus densifolius subsp. ayashensis (Kahramankazan), Astragalus kochakii (Kahramankazan) and Rumex patientia (Patience Dock) (Kahramankazan) plants, respectively. The lowest 226Ra, 232Th and,4 K activity concentration plants were determined respectively as Rumex patientia (Mamak), Lavandula angustifolia (Kızılcahamam), and Astragalus acikirensis (Polatlı). The establishment and routine repetition of environmental radioactivity monitoring programs in each region are important for human and animal health, and the results of this study gain importance for Ankara and its surroundings in terms of environmental health.

ANNUAL EFFECTIVE DOSE ESTIMATION DUE TO THE NATURAL RADIOACTIVITY IN YAM TUBERS (Dioscorea rotundata) CULTIVATED IN NORTHCENTRAL NIGERIA

Yam tubers (Dioscorea rotundata) and soil from commercially cultivated farmland in northcentral Nigeria were collected and investigated for their natural radioactivity content using a 3” × 3” NaI(Tl) gamma detector. Average activities of 238U, 232Th and 40K in the investigated farm soil were 38.13±3.76 Bq kg-1, 15.06±0.99 Bq kg-1 and 381.80±15.50 Bq kg-1, respectively. The results agree with the world’s acceptable levels of safety. Activities measured in the yam tubers were in the range from BDL -76.68±9.73 Bq kg-1 for 238U, BDL - 19.77±1.30 Bq kg-1 for 232Th and 312.50±20.73 - 627.94±38.37 Bq kg-1 for 40K, with average values of 29.23±4.0, 13.10±0.72 and 445.10±27.20 Bq kg-1, respectively. The total effective dose from radionuclide intake from yam ingestion fluctuated between 272.12 μSv y-1 and 935.97 μSv y-1. Correlation analysis identified 238U and 232Th as the leading contributors to the total effective dose from ingesting yam tubers cultivated in northcentral Nigeria.

Influence of phosphate fertilizers on the radioactivity of agricultural soils and tobacco plants in Kenya, Tanzania, and Uganda

Three brands of NPK fertilizers that contain variable concentrations of natural radioactivity are commonly used in tobacco plantations in Kenya, Tanzania, and Uganda. Tobacco plants are known for hyper-accumulation of natural radionuclides, particularly 238U. This study investigated if the elevated radioactivity in phosphate fertilizers could enhance radioactivity in soils and tobacco plant leaves. The 232Th, 238U, and 40K radionuclide levels in NPK-fertilized soils and tobacco leaves were measured using gamma-ray spectroscopy. The research included a one-year reference experiment with tobacco growing in plots, a ten-year semi-controlled experiment in well-managed tobacco farms, and a field survey of radioactivity in soils and tobacco leaves at three traditional tobacco fields in Migori (Kenya), Urambo (Tanzania), and Kanungu (Uganda). The findings demonstrated that soils and tobacco leaves exposed to NPK fertilizers with increased radioactivity had activity concentrations of 232Th, 238U, and 40K that were considerably higher (at all sites) than in the control samples (with no use of NPK fertilizers). As the continued application of NPK fertilizers raises concentrations of 232Th, 238U, and 40K in agricultural soils, the study assessed radiological risks for humans from exposure to agricultural soils enriched with phosphate fertilizers, and it was found to be below the exposure limit of 1 mSvy-1 suggested by the International Commission on Radiological Protection (ICRP). However, tobacco consumers, both by snuffing and smoking, may face significant radiological risks, as the snuffing and smoking resulted in effective doses that were 2.41 to 6.53 and 1.14 to 2.45 times greater than the average yearly dose that the general public receives from inhalation of natural radionuclides (United Nations Scientific Committee on Atomic Radiations estimates). Furthermore, the results indicate that the lifetime excess cancer risk for tobacco snuffers and smokers ranged from 5 × 10-5 to 24.48 × 10-3 and 2.0 × 10-5 to 9.18 × 10-3, respectively. The influence of phosphorus-derived fertilizer containing relatively high natural radioactivity, potential human radiation exposure, and radiological risk due to gamma radionuclides is estimated and discussed. The results reveal that applying phosphate fertilizers enhances natural radioactivity in soil and is subsequently influenced by soil to tobacco plant uptake. Therefore, the study recommends that countries use fertilizers with lower radionuclide content to conserve soil quality and reduce gamma-emitting radionuclides in tobacco plants.

Interpretation of natural radionuclides with respect to the petrological aspects: A study along the coastal region of Azhithala, Southwest coast of India

In the present study the activity concentration of natural radionuclides viz. 40K, 226Ra, and 232Th in the sand samples of coastal regions of Azhithala, Kerala measured using the 5″ × 5″ flat type NaI (Tl) detector. The radiological parameters such as absorbed dose rate (indoor and outdoor), annual effective dose, radium equivalent activity, and excess lifetime cancer risk were measured and compared with the Indian and World average values. The activity concentration of all natural radionuclides is well within the Indian and world average values except for the activity concentration of 232Th. The higher concentration of natural radioactivity in the study area is due to the deposition of weathered zircons or monazites from charnokite rocks. The charnokite group is the predominant lithology of the south the of Kasaragod district. The active erosion by the rivers might be the reason for the presence of the zircons or monazites in the study area. The results of the study are discussed in detail in this manuscript.

NORM measurements at Kalloni and Gera Gulfs, Lesvos Island, Greece

Natural radioactivity measurements were held in the beach sands of the two main gulfs (Gera, Kalloni) of Lesvos Island, Greece. These gulfs host thermal springs and are preferred tourist destinations throughout the year. Dose rates and concentrations of natural radioactivity (232Th series, 226Ra and 40K) and 137Cs were measured in-situ and in the laboratory by means of gamma ray spectroscopy. Ten beach sand samples were collected from each gulf. The in-situ measurement and the dose rate determination was achieved via a portable NaI scintillation detector (SpriID). The activity concentration calculations were realized in the laboratory, with the use of a high purity germanium detector, and then they were also used to estimate dose rates. The in-situ measured and estimated dose rates were compared to verify the different approaches. The highest values (activity concentrations and dose rates) were found at the beaches of Kalloni Gulf compared to those of Gera Gulf, which may be attributed to the granulometry.