mSv Year Research Articles

Assessment of groundwater quality, irrigation suitability, and health risks from radon and heavy metals near Ilokun dumpsite, Ado-Ekiti, Nigeria

ABSTRACT Concentrations of 222Rn and other toxic metals (Ni, Cu, Fe, Cd, Zn, Pb, Cr, and Mn) were measured by alpha spectrometry using Rad7 and atomic absorption spectrophotometry, respectively, in the water samples from the Ilokun dumpsite, Ado-Ekiti, Nigeria. The physicochemical parameters of the groundwater were also assayed to determine its suitability for drinking and irrigation purposes. While the physicochemical parameters met the World Health Organization (WHO)-safety standards, Cu, Fe, Cd, Pb, Cr, and Mn exceeded permissible limits. Hazard index (HI) values for adults (8.40) and children (39.23) indicated heightened susceptibility to non-carcinogenic health risks among both age group populations. The 222Rn concentrations present in the studied samples range from 5.4 to 23.1 Bq l−1 with an average of 13.9 Bq l−1. Approximately 60% of the samples have radon concentrations above the US Environmental Protection Agency (EPA)-maximum contaminant level of 11.1 Bq l−1. The evaluated radiation doses to the stomach and respiratory tract due to radon content in the water are well below the WHO-specified individual dose criterion of 0.1 mSv year−1. This study suggests a need for groundwater resource management strategies and measures to protect human health from radiological and toxicological risks associated with groundwater consumption around the Ilokun dumpsite.

Health risk assessment due to uranium contamination in groundwater: MATLAB based Monte-Carlo simulations

ABSTRACT Uranium contamination is a growing concern due to its inherent toxicity, which poses a significant threat to human health. The health risk assessment due to uranium contamination in groundwater of Mansa district, Punjab (India) is investigated. The LED LF-2a Fluorimeter model by Quantalase (Indore) was used for measurement of uranium concentration in groundwater collected in October 2021 from twenty-six locations. A comparison is conducted between the deterministic and probabilistic approaches since the deterministic approach might either underestimate or exaggerate the risk estimation. Monte-Carlo simulations are used to curtail the associated uncertainties in the data. The simulations are carried out in MATLAB for risk assessment and sensitivity analysis. The deterministic and probabilistic approaches are used to calculate hazard quotient, excess cancer risk and annual effective dose. Using probabilistic approach, the hazard quotient for male and female at 5th percentile is 4.36 and 3.81, respectively. Similarly, the hazard quotient for male and female at 95th percentile is 38.95 and 34.26, respectively. The mean hazard quotient is 18.45 and 15.68 for male and female, respectively, using deterministic approach. The hazard quotient is greater than 1 for both genders (male and female) and excess cancer risk is also higher than 10−4 using both deterministic and probabilistic approaches. The annual effective dose using deterministic approach is 0.23 mSv year−1 whereas using probabilistic approach, the 5th and 95th percentile is 0.56 mSv year−1 and 4.33 mSv year−1, respectively. The sensitivity analysis indicated that the overall risk is more sensitive to concentration of uranium in groundwater and the exposure frequency. This study emphasises on the hazards posed to humans by the ingestion of uranium contaminated groundwater, hence stressing the urgency for taking actions to protect the population of the study area.

Assessment of radiological hazards from radioactivity natural of cement used in Dwellings in Rio de Janeiro, Brazil

Brazil is the fourth largest cement consumer in the world and the largest producer in Latin America, around 1.3% of global production. The main inputs in the manufacture of cement are limestone and clay. Few studies have been carried out in the country on the risk of these materials used in civil construction. Therefore, the objective of this present work is to evaluate the radiological danger that they can present to society. Gamma spectrometry analysis on 16 samples of different brands of cement used as construction material in Rio de Janeiro (Brazil) was performed in this study, using an HPGe detector and the Genie 2000 data acquisition software. Samples were set to count for an accumulation time of 14,400 s (4 h) and all measurements were corrected to eliminate background and backscattering. Activity concentrations are determined for 226Ra was from (41.2 ± 1.6 to 174.9 ± 3.9) Bq kg−1, 232Th was from (15.7 ± 0.5 to 43.1 ± 0.7) Bq kg−1 and 40K was from (82.6 ± 7.2 to 254 ± 17) Bq kg−1. To assess radiological health risks: mean values of Radium Activity Equivalent 150.0 ± 3.4 Bq kg−1, Annual Gonadal Dose Equivalent 468 ± 11 μSv year−1 and Lifetime Excess Cancer Risk (ELCR) 2.42 ± 0.06 were calculated. Total Absorbed Dose Rates ranged from 72.2 ± 1.7 to 225.1 ± 5.2 nGy h−1. The damage to collective health was also estimated from the annual effective dose rates with an estimated total cost of damage to health of US$ 130 million. Values are generally within global limits reported by UNSCEAR.

Environmental and mineralogical studies on the stream sediments of Baltim–El Burullus coastal plain, North Delta, Egypt

This work is mainly concerned with the effect of anthropogenic activities and natural radioactivity due to the presence of highly radioactive black sand spots, factory construction, and shipping, in addition to other activities like agriculture on human beings. Forty samples were collected along Baltim–El Burullus coastal plain to detect the effect of these problems and determine the suggested solutions. The black sand of the Baltim–El Burullus coastal plain exhibits a considerable amount of economically heavy minerals, their ratio relative to the bulk composition in the investigated samples ranges from 3.18 to 10.5% with an average of 5.45%. The most important of them are magnetite, ilmenite, rutile, leucoxene, garnet, zircon and monazite. The existence of some radioactive-bearing accessory mineral deposits like zircon and monazite led to measuring the naturally occurring radionuclides 226Ra, 232Th and 40K to evaluate the excess lifetime cancer risk (ELCR). The results showed that these concentrations are 19.1 ± 9.73, 14.7 ± 9.53 and 211 ± 71.34 Bq kg−1 were lower than the corresponding reported worldwide average of 35, 45, and 412 Bq kg−1 for each radionuclide (226Ra, 232Th, and 40 K). The gamma hazard indices such as absorbed dose rate (Dair), the annual effective dose (AED), and excess lifetime cancer risk (ELCR) factor were computed in the investigated sediments and all the results were found (Dair = 26.4 nGy h−1, AED = 0.03 mSv year−1, ELCR = 0.0001) to be lower than the values suggested by the United Nations Scientific Committee on the effect of Atomic Research (59 nGy h−1, 0.07 mSv year−1 and 0.0029 for Dair, AED and ELCR, respectively). The study suggests that the black sand is safe to use in various infrastructure applications at Baltim–El Burullus coastal plain. The levels of radioactivity are not high enough to pose a risk to human health.

Assessment of Be-7, Pb-210 and Po-210 Activities in Airborne Particulate Matter Over Istanbul, Türkiye.

Airborne particulate matter is one of the air pollutants which can have detrimental health effects in the human body. Radionuclides adsorb onto air particles and make their way to humans primarily through inhalation. Naturally-occurring radionuclides, 210Pb and 210Po, are of notable health concern due to their relatively elevated ingestion and inhalation doses. In the current study, activity concentrations of 7Be, 210Pb and 210Po were determined in air particulate matter (PM). PM2.5 was collected on the European side, while PM10 was collected on the Anatolian side of Istanbul. Be-7, 210Pb and 210Po activities were found to be 5.17 ± 2.35, 0.96 ± 0.42; 0.25 ± 0.14 mBq m- 3 in Anatolian side, respectively. Be-7, 210Pb and 210Po activities were found to be 3.81 ± 2.27, 0.62 ± 0.29, 0.29 ± 0.26, mBq m- 3 in European side, respectively. The ratio of 210Po/210Pb was found to be higher (0.47 ± 0.31 for PM2.5 and 0.34 ± 0.27 for PM10) than the global average of 0.1. This result can be explained by the fact that Po is more volatile than Pb and enhanced in the air by the combustion process. Inhalation dose rates of 210Pb and 210Po due to PM10 exposure were calculated to be 7.70 ± 3.30 and 4.05 ± 2.31 µSv year- 1, respectively. Pb-210 bioaccessibility was assessed by the extraction of the particles in simulated lung fluids. Approximately 24.8% of inhaled 210Pb was estimated to be bioaccessible. This study suggests that 210Po and 210Pb activities are partially enhanced in the air particles in Istanbul and should be regularly monitored.

Assessing radioactive contaminants in Kathmandu soils: measurement and risk analysis.

Soil samples from vegetable farmland in densely populated wards of Nepal were analyzed for natural radionuclide levels, employing a NaI(Tl) 3" [Formula: see text] 3" gamma detector. The study aimed to evaluate the causes of radiation risk, attributing it to soil contamination resulting from the rapid urbanization and concretization that followed the earthquake in 2015. The activity concentration of radium-226, thorium-232, and potassium-40 and the ranges observed are 2.080±0.084-33.675±1.356 Bq kg[Formula: see text], 17.222±0.198-119.949±1.379 Bq kg[Formula: see text], and 11.203 ± 0.325-748.828±21.716 Bq kg[Formula: see text], respectively. The average values obtained for hazard indices are as follows: radium equivalent activity (82.779 Bq kg[Formula: see text]), absorbed dose rate (36.394 nGy h[Formula: see text]), annual effective dose equivalent (0.045 mSv yearr[Formula: see text]), gamma index (0.291), external hazard index (0.224), internal hazard index (0.253), excess lifetime cancer risk (0.159), annual gonadal dose equivalent (243.278 mSv year[Formula: see text]), alpha index (0.054), and activity utilization index (0.716). However, in most places, thorium-232 concentration is greater than those of the world average and recommended values. In specific locations such as Ward 4 in Baluwatar, the soil was found to have concentrations of Ra[Formula: see text] and K[Formula: see text] exceeding recommended limits. Despite this localized concern, the overall analysis of hazard indices across the studied areas revealed that most values were within permissible limits. This suggests that, on a broader scale, radiation exposure may not be a significant concern in the investigated regions. Nonetheless, the study recommends regular monitoring in additional locations to ensure a comprehensive and ongoing assessment of radiation levels.

Development of a methodology for assessing radiological dose due to use of NORM sludge as fertilizer

In Europe, the general obligation to recycle drives for increased reuse of residues containing Naturally Occurring Radioactive Material (NORM). In agriculture, this has led to the reuse of sludge produced by groundwater filtration facilities as a means of fertilization. In the frame of the RadoNorm project, a methodology was developed for dose assessment of agricultural workers and other members of the public living near agricultural fields in which NORM-containing sludge is applied. Appropriate exposure scenarios were identified and modelled for each relevant NORM decay segment of both U-238 and Th-232 series, as well as for K-40. Dose assessments were performed using the software RESRAD-ONSITE with dose coefficients for external and internal exposure taken from the latest publications from the International Commission on Radiological Protection (ICRP). The objective was to develop a generic methodology to quantify exposure and to obtain screening values – so-called Operational Levels (OLs). These OLs pertain to the activity concentration of natural radionuclides (in terms of kBq kg−1) present in sludge that is reused in agriculture, for which dose criterion of 1 mSv year−1 is complied with. OLs can be used as screening tools by an authority/operator, even non-experts in the field of radiation protection.Results showed that the most critical decay segments are Ra-226+ and Ra-228+, for which OLs of the order of 1 kBq kg−1 were estimated. For all the other radionuclides, the calculated OLs are much higher than the activity concentrations typically found in sludge from water treatment facilities, and the radiological impact expected is well-below 1 mSv year−1. The methodology and results of this study could contribute to the update of the Clearance Levels and discharge levels reported in the European guidelines RP 122 Part II and RP 135, respectively.

Investigations of indoor radon levels and its mapping in the Greater Accra region, Ghana

In this work, the indoor radon concentration and radiation dose risks were studied in dwellings within the Greater Accra region, using CR-39 detectors. The indoor radon concentrations ranged from 36.1 ± 2.7 to 92.0 ± 5.2 Bq m−3 with an annual average of 50.8 ± 3.4 Bq m−3. The annual mean effective dose was estimated as 1.3 mSv year−1. Excess lifetime cancer risk and lung cancer cases were assessed with 5% annual lung cancer deaths due to radon was realized. Indoor radon maps created with ArcGIS software over a 5 × 5 km2 grid showed radon prone areas in the region.

Assessment of naturally occurred radiation hazards in chemical and organic fertilizers used in Chattogram area, Bangladesh

ABSTRACT The present work deals with identifying and determining the activity levels of naturally occurring radionuclides 226Ra and 232Th series, their decay products and 40K in chemical and organic fertilisers used in the Chattogram area, Bangladesh. A total of 39 samples collected from retail markets were investigated, out of which 28 are chemical fertilisers and the others are organic fertilisers. The average activity concentration of 226Ra and 232Th found in TSP fertiliser are 304.57 ± 36.0 and 19.1 ± 6.8 Bq kg−1 respectively and the average activity concentration of 40K in MOP fertiliser is found as 10,311.11 ± 1168 Bq kg−1. In the organic fertiliser samples, the mean concentration of 226Ra, 232Th and 40K are 17.35 ± 3.11, 7.20 ± 1.74 and 437.14 ± 42.58 Bq kg−1, respectively. The mean absorbed dose rates were measured after the end of our experiment, and the value was found to be 91.39 nGy h−1. The combined (indoor + outdoor) annual effective dose equivalent was also estimated as 0.322 mSv year−1. The mean radium equivalent activity found to be 190.15 ± 26.74 Bq kg−1 is well below the recommended level of 370 Bq kg1. The internal hazard index, external hazard index, and radioactivity level index of the investigated fertiliser samples were found as 0.56 ± 0.034, 0.54 ± 0.08 and 0.69 ± 0.10, respectively. From the calculated hazard parameters, the excess lifetime cancer risk (ELCR) was found to be higher than the world average in most of the chemical fertilisers except in DAP and BOR, while the organic fertilisers show lower than the world average. The obtained results reveal that there are no significant radiation hazards due to natural radionuclides of the fertiliser samples in the studied area, but the higher concentration of 40K in MOP suggests strengthening the regulatory work. Overall, this study highly recommends the use of organic fertilisers, as these kinds have hazard parameters lower than the recommended levels.

Effect of mineral fertilisers application on the transfer of natural radionuclides from soil to radish (Raphanus sativus L.)

Non-controlled usage of mineral fertilisers in agriculture land of Kazakhstan is a concerning issue, due to possible contamination of the soil by radionuclides. Pot experiment of growing of R. sativus with application of mineral fertilisers was carried out under natural conditions. Two commonly used mineral fertilisers, mono-potassium phosphate and ammonium nitrate, were chosen in the frame of current research to determine the impact of mineral fertiliser on transfer of natural radionuclides from soil to R. sativus edible part. For this goal, the activity concentrations of natural radionuclides U-234, U-238, Th-230, Th-232 and Ra-226, were determined in both R. sativus edible part and the investigated soil by using alpha-particle spectrometry. The highest activity concentrations were found for R. sativus edible part growing on soil that was fertilised by mono-potassium phosphate and were equal to 174 ± 17, 134 ± 15, 62 ± 4, 15 ± 2 and 2.8 ± 0.6 Bq/kg for U-234, U-238, Th-230, Th-232 and Ra-226, respectively. The results of soil-to- R. sativus edible part transfer factor for different radionuclides varied depending on the mineral fertiliser used. For evaluation of impact during consumption of R. sativus edible part by a population of Kazakhstan, annual effective ingestion dose and excess lifetime cancer risk were determined. The highest annual effective ingestion dose was found for R. sativus edible part cultivated in mono-potassium phosphate-fertilised soil and was equal to 4.4 μSv year−1.

A brief radiological survey and associated occupational exposure to radiation in an open pit slate mine in Kashan, Iran

A comprehensive radiological survey was carried out in an open-cut slate stone quarry. The activity of 226Ra, 228Ra and 40 K in the ore samples were measured as 38 ± 5, 41 ± 6 and 869 ± 52 Bq kg1, respectively. Outdoor radon and indoor radon concentrations were measured from 37 ± 7 to 193 ± 11 Bq m−3 (77 ± 8 Bq m−3), and 49 ± 6 to 253 ± 23 Bq m−3 (131 ± 13 Bq m−3), respectively. The average indoor and outdoor gamma dose were measured as 116 and 84 nSv h− 1, respectively. The annual effective doses were estimated between 1.0 ± 0.1 and 3.3 ± 0.3 mSv year−1. The annual lung cancer risks were calculated in the range of 3.3 × 10−2 to 13.12 × 10−2 % (7.72 × 10−2%).

Radiation Awareness for Endovascular Abdominal Aortic Aneurysm Repair in the Hybrid Operating Room: An Instant Operator Risk Chart for Daily Practice

Introduction: While the operator radiation dose rates are correlated to patient radiation dose rates, discrepancies may exist in the effect size of each individual radiation dose predictors. An operator dose rate prediction model was developed, compared with the patient dose rate prediction model, and converted to an instant operator risk chart. Materials and Methods: The radiation dose rates (DRoperator for the operator and DRpatient for the patient) from 12,865 abdomen X-ray acquisitions were selected from 50 unique patients undergoing standard or complex endovascular aortic repair (EVAR) in the hybrid operating room with a fixed C-arm. The radiation dose rates were analyzed using a log-linear multivariable mixed model (with the patient as the random effect) and incorporated varying (patient and C-arm) radiation dose predictors combined with the vascular access site. The operator dose rate models were used to predict the expected radiation exposure duration until an operator may be at risk to reach the 20 mSv year dose limit. The dose rate prediction models were translated into an instant operator radiation risk chart. Results: In the multivariate patient and operator fluoroscopy dose rate models, lower DRoperator than DRpatient effect size was found for radiation protocol (2.06 for patient vs 1.4 for operator changing from low to medium protocol) and C-arm angulation. Comparable effect sizes for both DRoperator and DRpatient were found for body mass index (1.25 for patient and 1.27 for the operator) and irradiated field. A higher effect size for the DRoperator than DRpatient was found for C-arm rotation (1.24 for the patient vs 1.69 for the operator) and exchanging from femoral access site to brachial access (1.05 for patient vs 2.5 for the operator). Operators may reach their yearly 20 mSv year dose limit after 941 minutes from the femoral access vs 358 minutes of digital subtraction angiography radiation from the brachial access. Conclusion: The operator dose rates were correlated to patient dose rate; however, C-arm angulation and changing from femoral to brachial vascular access site may disproportionally increase the operator radiation risk compared with the patient radiation risk. An instant risk chart may improve operator dose awareness during EVAR.

The potential use of remote sensing and GIS techniques for sustainable development in the coastal plain between Halayb and Shalateen, Egypt

The Red Sea coastal plain between Halayb and Shalateen represents one of the localities with great potential for future sustainable development. The area is almost flat with Quaternary deposits from the western wadies towards the Red Sea shoreline. Due to the general character of the area, it is promising for reclamation, tourism, and industrial activities. This paper highlights the environmental characteristics of the area for sustainable development using remote sensing and GIS techniques. Geomorphological analysis, assessment of soil pollution (radiological and heavy metal distribution), groundwater assessment, and detection of change to the shoreline have been carried out. Geomorphologically, the most suitable part of the study area for future planning is the southeastern region. The northern area is not appropriate as it is classified as third-order drainage and will be exposed to flash floods that threaten the infrastructure of the native settlements, newly built tourist villages, and the coastal roads. The groundwater aquifers in the study area are Quaternary sediments and fractured basement rocks. All groundwater samples have acceptable soluble sodium percentages (SSPs) with relatively low sodium and very high saline, making them suitable for salt-tolerant crops on soil with good permeability and special leaching. The Wadi Diit area is in the safe range of radioactivity with a maximum effective dose rate of 0.37 mSv year−1, which does not represent any harm to living organisms. Furthermore, the soil studied from the area under consideration reflects heavy metal concentrations lower than the maximum allowable levels. The change detection study showed that there is a balance between erosion and accretion rates with no significant change in the shoreline morphology that would affect future planning in the coastal area.

Natural radioactivity at beach sands in Ilha Grande, Southeastern Brazil

In order to analyze temporal variability on the gamma dose absorbed in the air in beaches in Ilha Grande, Brazil, in 2011–2012 new measurements were made in four of ten beaches analyzed previously in 2001. The measurements were performed directly with a proportional detector. The values varied between 47 ± 5 (Lopes Mendes) and 97 ± 11 nGyh−1 (Caxadaco) Praia Preta. The average annual effective dose was 0.08 ± 0.02 mSv year−1 , in line with the world average of effective external doses, 0.07 mSv year−1 according to UNSCEAR. No statistically significant change was observed after 10 years.

Distribution of 210Pb and 210Po in ground water around uranium mineralized area of Jaduguda, Jharkhand, India

In present study, distribution of 210Po and 210Pb in ground water in uranium mineralized zone of Jaduguda in East Singhbhum region of Jharkhand state, India is evaluated. Activity concentration of 210Po ranges from < 0.08 to 7.41 ± 0.90 mBq L−1 and activity concentration of 210Pb was ranging from 0.76 ± 1.27 to 34.43 ± 3.89 mBq L−1. Comparable results were observed for the samples from upstream and downstream direction with respect to uranium mining and ore processing facilities at Jaduguda reflecting restriction of migration of radionuclides from facilities. Activity concentrations of 210Pb and 210Po observed were below the guidance value of WHO. Average ingestion doses from 210Pb and 210Po in groundwater were calculated to 1.91 ± 1.60 µSv year−1 and 5.75 ± 4.45 µSv year−1respectevely. 210Po was observed to be decreasing with SO42− in ground water indicating possible fixation of 210Po with process involving formation of sulfates.

Yearly effective dose due to consumption of wild black fungus grow in southern Iraq assessed by measuring of radionuclide concentrations

Wide range of studies have been conducted around the word focusing on the evaluation of radionuclide concentrations in foodstuff. This work focusing on the estimation of the annual effective dose due to radionuclide activity in Iraqi wild fungus, specifically black desert truffles. The fungus have been collected from the desert of As Samawah governorate in the south of Iraq as it is grow in a large amount. The average activity concentrations for 238U, 232Th, 40K and 137Cs were 3.95, 2.53, 260.36 and 1.78 Bqkg −1 respectively in all 10 collected truffle samples. The average annual effective doses from 238U ingestion were 0.36 and 0.54, from 232Th ingestion were 1.16 and 1.47, from 40K ingestion were found to be 3.23 and 319.20 and from 137Cs were 0.05 and 0.04 μSv year−1 in adults and children respectively. The measured values were less than the assessed world mean value from the exposure caused by natural radionuclide ingestion that documented in the literature (0.29 mSv year−1).

Trend of strengthening clearance regulation in Japan and concerns about its worldwide effects on regulations for natural and artificial radionuclides.

The Nuclear Regulation Authority (NRA) of Japan invited comments from the public on a revised guide on measurement and evaluation for clearance in 2019, which included a strict decision on how to treat uncertainties in the measurement and the nuclide vector. To resolve the issue on the uncertainty in clearance, a probabilistic approach had been established previously in the Atomic Energy Society of Japan Standard and incorporated into International Atomic Energy Agency (IAEA) Safety Report No. 67. NRA's new decision on the uncertainty in clearance was up to 10 times stricter than the probabilistic approach. This issue has been discussed at an international level in the framework of the ongoing revision of IAEA Safety Guide RS-G-1.7. This discussion on the uncertainty in clearance has raised serious concerns about its effects on other radiological protection regulations worldwide. This is because if we need strict treatment for the uncertainty in clearance, the same or even stricter treatment for conformity assessment may have to be applied to other radiological protection criteria for doses exceeding 10 µSv year-1. Radiological protection experts including regulators, professionals, and operators should be aware of the essential meaning of the radiological protection criteria by considering the background scientific basis on which they were established.

Semi-experimental evaluation for radon exhalation rate and excess lifetime cancer risk from potential radon exposure for using fly ash building materials

In this work, the radon exhalation, annual effective dose and excess lifetime cancer risks due to the exposure of radon released from raw building materials containing fly ash of different fractions were evaluated. The 226Ra and 222Rn concentrations were evaluated by the measurements on HPGe gamma spectrometer, RAD 7 radon detector combined with model calculation of radon exhalation for standard rooms. The results indicated that the emanation fraction for fly ash is lower than the corresponding value for soils and rocks. The surveyed building materials of containing fly ash can result in an indoor radon concentration up to 1.7 Bq m−3 which is below the recommended value of 100 Bq m−3 by WHO, the annual effective dose increases from 0.007 to 0.022 mSv year−1, the excess lifetime cancer risks ranges from 0.027 × 10–3 to 0.085 × 10–3 with the ratio of 3.2 for the additional fly ash content in cement up to 75%. In the meanwhile, it has a down trend and influences inconsiderably on these parameters for sand. The obtained mean annual effective doses are lower than the dose limitation of 10 mSv year−1 recommended for occupational workers.

Environmental assessment of radioactivity levels and radiation hazards in soil at North Western-Mediterranean Sea coast, Egypt

The present work aims to obtain adequate knowledge about the natural radioactivity levels and the related radiation hazard at the northwestern coastal zone of Egypt as part of the Egyptian regulations and nuclear law. Thirty-eight soil samples of different geologic formations were collected and analyzed using gamma spectrometer equipped with hyper-pure germanium (HPGe) detector. The mean activity concentrations of 238U, 226Ra, 232Th and 40K in all soil samples are 29.40, 25.18, 11.22 and 159.16 Bq kg−1, respectively. Those activity concentrations are below the soil world average. The activity concentrations of 238U are found to be higher than that of 226Ra and 232Th. The spatial patterns of the activity concentrations of these radionuclides were also presented using the geographical information system (GIS). Radiation hazard indices were assessed through the calculation of radium equivalent activity (Raeq) Bq kg−1, external and internal hazards (Hex, Hin), absorbed dose rate (ADR) nGy h−1 and annual effective dose (AED) mSv year−1. The average values of ADR and AED are 25.41 nGy h−1 and 20 μSv year−1, respectively. These values are below the soil world average of 59 nGy h−1 and the effective dose limit of the public radiation exposure of 1 mSv year−1.

Assessment of gamma radiation levels of beach sands in Bitlis region of Lake Van

Natural gamma radioisotope activity concentration levels in beach sands in the Bitlis region of Lake Van, in eastern Turkey, were determined using an HPGe detector. A total of 15 different beach sand samples were collected from Ahlat, Adilcevaz, and Tatvan shoreline regions, and then 226Ra, 232Th, 40K, and 137Cs radioisotope activity concentrations were measured. Mean values of gamma emissions for each radioisotope were determined as 58.78, 65.89, 1590.25, and 4.84 Bq kg−1 for 226Ra, 232Th, 40K, and 137Cs, respectively. Mean radium equivalent activity, absorbed gamma dose rate, annual effective dose, and external hazard index values were calculated as 275.45 Bq kg−1, 135.41 nGy h−1, 0.17 mSv year−1, and 0.74, respectively.