Mean Annual Effective Dose Research Articles

Assessment of Radon-222 in Selected Water Sources in Gwagwalada, Gwagwalada Area Council, FCT, Abuja, Nigeria

The exposure of a population to high concentration of Radon-222 for a long period has significant health effects ranging from respiratory functional changes to cancer of the lungs. Also, a very high level of Radon-222 in drinking water can lead to stomach and gastrointestinal tract cancer. In this work, the activity concentrations of Radon-222 (222 Rn) were investigated from thirty (30) water samples which includes twenty (20) borehole water samples and ten (10) well water samples from Gwagwalada town using liquid scintillation counter at the Centre for Energy Research and Training (CERT) Ahmadu Bello University Zaria, Nigeria. Radon-222 concentrations obtained from this analysis ranged within (7.72 to 172.30) Bq/L. The highest and the lowest Radon-222 activity concentration were recorded from borehole and well water samples at Abattoir and kasuwan Derey respectively. Borehole water samples recorded the highest mean radon concentration of 45.11Bq/L while well water samples recorded the lowest mean Radon-222 concentrations of 27.60Bq/L. From computed results, it was observed that 88.89% of the recorded values were found to be above the world average Maximum Contamination Level (MCL) of 10Bq/L set by the World Health Organization and the MCL of 11.1Bq/L set by the United States Environmental Protection Agency (USEPA, 1991). Similarly, 15% of the recorded values were above the recommended action level of 100Bq/L set by the World Health Organization (WHO, 2008). Also, the corresponding Mean Annual Effective Doses estimated for the three (3) categories of people from the two (2) water types were found to be (0.331, 0.662 and 2.318) mSv/y in borehole water for adults, children and infant respectively. While due ingestion of Radon-222 in well water samples were found to be (0.201, 0.403 and I.417) mSv/y for adults, children and infants respectively. All the Mean Annual Effective Doses were found to be above World Health Organization's...

Continuous monitoring of outdoor natural gamma absorbed dose rate in air: a long-term study in Kolkata, West Bengal, India

This study contributes to the overarching Indian Environmental Radiation Monitoring Network initiative, concentrating on the continual assessment of the gamma absorbed dose rate in outdoor air attributable to natural gamma radiation in Kolkata, West Bengal, India. Over a span of fourteen years (2011–2024), data were gathered from 32 monitoring sites within the city utilizing permanently installed Geiger-Mueller detector-based environmental radiation monitors. This paper offers an analysis of extensive findings from long-term monitoring efforts. The absorbed gamma dose rate in outdoor air varied among the monitoring sites, ranging from 78 ± 5 to 137 ± 4 nGy h− 1, with a mean value of 107 ± 12 nGy h− 1. The estimated mean annual effective dose due to outdoor natural gamma radiation ranged from 0.10 ± 0.01 to 0.17 ± 0.01 mSv y− 1, with an overall mean of 0.13 ± 0.01 mSv y−1.

Assessment of the residential radon concentrations in the Bakony Region, Hungary

ObjectiveTo investigate the current levels of indoor radon activity in the geologically complex Bakony Region of Hungary, which has been historically affected by industrial activities, and to identify areas that may require further monitoring and intervention. MethodsExperiments were carried out to measure quarterly indoor radon activity concentrations in ground-floor dwellings for a year using CR-39-type nuclear track detectors at 30 locations in 9 settlements to provide current information on the Bakony Region and identify areas requiring further attention. ResultsSince the annual average indoor radon activity concentration in the Bakony Region was 86 Bq/m3 and the maximum 274 Bq/m3, that is, less than the 300 Bq/m3 national and EU reference levels, it is considered safe. Two locations were equal to or exceeded the reference level during part of the year. While most of the Region exhibited high radon concentrations in the autumn and winter, two settlements presented inverse seasonal variations. ConclusionAlthough the autumn and winter values yielded a strong correlation with the annual mean and each other, this was not the case regarding the summer and spring values. The annual mean effective dose for the Region from the inhalation of radon and its progenies was estimated to be 2.2 ​mSv/year.

A review of radiation doses and associated parameters in Western Australian mining operations (2020-23)

Government policies have stimulated the Western Australian (WA) mining industry to position itself as a significant global supplier of critical minerals, including lithium and rare earths. In WA the lithology that supports these minerals is often associated with elevated concentrations of naturally occurring radioactive materials (NORMs) and the increase in the number of mining operations pursuing the minerals has witnessed a commensurate increase in the number of workers potentially exposed to the radiation emitted from the NORMs. The regulatory framework for radiation protection in WA mining operations underwent significant change with the implementation of the Work Health and Safety Act 2020 and Work Health and Safety (Mines) Regulations 2022 which both came into effect on the 31 of March 2022. Under the new framework mining operations identified as having workers who were likely to receive annual effective doses (EDs) from NORMS above one mSvy-1are referenced asrelevant mines (RM). RMs are required to submit an annual report of the estimates of EDs)received by their workforce to the mining regulatory authority (WorkSafe WA: Mines Safety). This research provides an overview of the new legislative framework and updates the information in Ralph and Cattani (2022J. Radiol. Prot.42012501) to include data derived from annual occupational EDs submitted by RMs in the three-year period spanning 2020-21, 2021-22 and 2022-23. In 2022-23, 38 mining operations were identified as RMs, an increase of ten from 2021-22 which in turn had increased by six from the 2020-21 reporting period. The mean annual ED reported for the three-year period was 1.0 mSv, the level at which regulatory intervention should be considered. The maximum ED was 4.9 mSv, just below the threshold of 5 mSv above which exposed workers are considered Designated Workers and are subject to focused monitoring. The collective effective annual dose of the mine worker population reached an historical maximum of 2339 man mSv in 2022-23. Analysis of the three main exposure pathways confirms that inhalation of long-lived alpha emitting radionuclides in dust remains the most significant contributor to worker EDs. Inhalation of radon-222 and radon-220 and their short-lived progeny, once considered as a negligible contributor to worker annual EDs is the second most significant exposure pathway. A declining trend in the number of samples collected per worker is highlighted as requiring remediation to provide confidence in the reported annual EDs. The transition to the new legislative framework for radiation protection in mines has been supported by the publication of guidance materials which have been widely endorsed by the industry.

Assessment of soil moisture on radon levels, radon exhalation, natural radioactivity, and radiological risks in offices and laboratories in GAEC

This study investigates the influence of moisture on soil radon exhalation, natural radioactivity in soil, and indoor radon concentrations in offices and laboratories at the Ghana Atomic Energy Commission (GAEC) and their associated radiological risks to workers. Radon exhalation rates were determined using the Sealed Can method. CR-39 SSNTD detectors were used to measure indoor radon concentrations. Gamma spectroscopy using HpGe detector was used to determine the activity concentrations of U-238, Ra-226, Th-232, and K-40 in the soil samples. The results showed mean concentrations of 14.3 ± 2.0 Bq/kg (CI 95%: 10.0–18.0) for U-238, 145.0 ± 10.0 Bq/kg (CI 95%:123.0–167.0) for K-40, 31.5 ± 6.0 Bq/kg (CI 95%: 24.0–39.0) for Th-232, and 15.6 ± 2.0 Bq/kg (CI 95%:14.0–29.0) for Ra-226. The results showed mean surface and mass exhalation rates of 6.9 ± 2.3 × 10−4 Bq/m2/h1 (CI 95%: 5.7 × 10−4 –12.6 × 10−4) and 2.4 ± 0.4 (CI 95%: 1.9–4.2) nBq/kg1/h1 respectively. The findings revealed mean indoor radon concentrations of 93.0 ± 10.0 Bq/m3 (CI 95%: 88.0–98.0), 111.0 ± 12.0 Bq/m3 (CI 95%: 102.0–119.0) and 145.0 ± 13.0 Bq/m3 (CI 95%: 135.0–155.0) in the offices, laboratories, and basements respectively, with laboratories and basements exceeding the WHO reference level of 100 Bq/m3. A strong inverse relationship between moisture levels and exhalation rates (r = −0.8) was observed, leading to a negative correlation (r = −0.3). Between the moisture levels and indoor radon levels. The research findings indicated a mean annual effective dose of 0.6 mSv/yr. (CI 95%: 0.5–0.6) to the workers, which is well below occupational and public dose limits. The lung cancer cases of workers were computed which ranged from 0.9 × 10−8 to 1.2 × 10−8 cases per million people per year, which is less than the limit range of 170–230 per million people per year recommended by ICRP but remaining with safe radiological limits for workers. This study identified moderate radon exposure risks at the GAEC, exceeding the WHO recommendation. The correlation and trend analysis demonstrate strong relationships between moisture, exhalation rates, radium, and indoor radon.

Simultaneous indoor radon/thoron and in situ outdoor gamma dose measurements and estimation of annual effective dose in a tin mining area of Jos Plateau, Nigeria.

Radon, a radioactive gas can increase the risk of lung cancer when breathe in. Indoor Rn-222 and Rn-220 concentrations were determined using passive radon monitor in some dwellings in a Sn mining area of Jos Plateau. Outdoor gamma radiation was also measured with a hand-held survey meter. The range of Rn-222 and Rn-220 concentrations was from 7-53Bq m-3 to 41-267Bq m-3 with averages of 27±17 and 92±65Bq m-3, respectively. The mean total effective dose due to Rn-222+Rn-220 was estimated as 2.84±1.57mSv y-1. Rn-220 contributed between 50 and 95% to the total annual effective dose. There was no correlation between indoor Rn-220 and Rn-222 concentrations in the dwellings. Outdoor gamma radiation measured was between 0.31±0.06 and 0.62±0.08μSv h-1, and mean annual effective dose calculated was 1.14±0.21mSv y-1. It is concluded from this study that thoron should not be neglected in dose assessment.

Annual Effective Dose Estimation from Radon Concentration in Commonly Consumed Bottled Water in Northcentral Nigeria

Radon (222Rn), the heaviest among the noble gas in the periodic table of element, is radioactive nuclide that is naturally available in rocks, soil and water. In this study, a total of ten (10) brands of commonly consumed commercial bottled water in northcentral Nigeria were collected and assigned for their radon concentration using liquid scintillation counter (LSC). The highest radon (222Rn) concentration of 0.073 Bq/l was recorded in C Way bottled water while Mr. V bottled water recorded the lowest 222Rn concentration value of 0.016 Bq/l. These values were below the parametric reference level of 11.1 Bq/l set by United State of America Environmental Protection Agency and lower than the permissible limit of 100 Bq/l by World Health Organization (WHO) and European Union. Computed total annual effective dose due to ingestion and inhalation of waterborne radon recorded the highest mean value of 0.187 μSv/y in C Way Bottled water and lowest value of 0.041 μSv/y in Mr. V bottled water. Mean total annual effective dose recorded for all the bottled water samples were found to be significantly lower than the safety limit of 0.1 mSv/y recommended by WHO. The likelihood of any radiation incidence among the public due to consumption of commercial bottled water is therefore negligible.

Assessment of Naturally Occurring Radionuclide in Soil Samples from Kutayi Mining Sites in Muya Local Government Area, Niger State, Nigeria

This work examines the Kutayi mining sites with a view of assessing the activity concentration and effective dose rate of NORM (i.e. 40K, 232Th and 226Ra) in these site absorbed in 8 soil samples collected from different areas within the Kutayi mining sites, A γ-ray spectrometry NaI (Tl) at CERT. ABU Zaria, was used to carry out the analysis of the soil samples. The result shows that, activity concentration for 40K ranged from 428.9269 to 93.6236 BqKg-1; for 226Ra it ranged from 50.1738 to 13.7891 BqKg-1 and for 232Th the ranged is from 52.1095 to 18.7457 Bq.Kg-1, the absorbed dose for 40K ranged from 17.8863 to 3.9041 ŋGy.h-1, for 226Ra the range is from 23.1803 to 3.1614 ŋGy.h-1 and for 232Th range from 31.47419 to 11.3224 ŋGy.h-1. The total mean absorbed dose rate is 42.5341 ŋGy.h-1 and the annual effective dose range from 0.0355 mSvy-1 (i.e. 36 – 76 μSv.y-1), with an mean annual effective dose of 0.0522 mSv.y-1 (i.e. 52.2 μSv.y-1, Also the mean Radium Equivalents (Raeq) obtained ranged from 64.0280 BqKg-1 (KT6) to 135.3245 BqKg-1 (KT8). This results show that, the Raeq is 370 BqKg-1 which is the requirement for soil to be used for dwellings; hence the soil from this site is suitable use for buildings. The mean Hext ranged from 0.1730 Bqkg-1 (KT6) to 0.3438 Bqkg-1 (KT8). The maximum allowed value of (Hext = 1) corresponds to the upper limit of Raeq (370 BqKg-1) in order to limit the external gamma radiation dose from the soil to 1.5 mGy y-1, i.e. index should Hext = 1. All these values for Iα are below the maximum permissible value of Iα= 1 which corresponds to 200 Bq.Kg-1. Hence no radiological hazard is envisaged to dwellers of the study areas and the miners working on those sites.

Assessment of Indoor and Water Radon Concentrations in Esenyurt and Beylikdüzü Districts of Istanbul, Marmara Region, Turkey

The radon activity concentration measurements for indoor and tap water were studied in Esenyurt and Beylikdüzü districts of Istanbul Province, Turkey. The mean radon concentration value received from thirty-six passive radon detectors was obtained as 63.56 Bq/m3. The mean annual effective dose for indoor radon measurements is 1.60 mSv/y in this measurement period. The radon activity results of calculated tap water samples were under 0.8 Bq/L. The annual effective doses resulting from ingestion and inhalation were calculated to evaluate the health risk across various age groups. All radon measurement results, and the associated calculated data for ingestion and inhalation remained below the threshold values established by international organizations

Forensic GIS γ-Radiation Mapping and Associated Radiological Health Risk Assessment of the Premier Cities of Sapele, Oghara and Koko; South-South Nigeria

The GIS mapping of the terrestrial γ -radiation levels and evaluation of the radiological health hazard to residents of Sapele, Oghara and Koko cities in Nigeria have been carried out, using a Digilert nuclear radiation survey meter, geographical positioning system (GPS) and arc ArcGIS software. In Sapele (4 zones), the measured average gamma radiation levels ranged from 0.011 ± 0.003 mR h − 1 to 0.014 ± 0.005 mR h − 1 , while in Oghara (5 zones), the average gamma radiation levels ranged from 0.013 ± 0.002 mR h − 1 to 0.026 ± 0.009 mR h − 1 and for Koko(4 zones), the values obtained ranged from 0.018 ± 0.003 mR h − 1 (1.54 ± 0.11 mSvy − 1 ) to 0.023 ± 0.008 mR h − 1 respectively, with overall mean value of 0.017 ± 0.006 mR h − 1 (1.43 ± 0.51 mSvy − 1 ) . The mean absorbed gamma dose rate for three cities of Sapele, Oghara and Koko are 106.50 ± 22.33 nGy h − 1 , 167.28 ± 22.59 nGy h − 1 and 176.80 ± 24.74 η Gyh − 1 respectively. The mean annual effective dose rate (AEDR) for the three cities is 0.13 ± 0.03 mSvy − 1 , 0.20 ± 0.07 mSvy − 1 and 0.22 ± 0.06 mSvy − 1 mSvy − 1 respectively , while the mean excess lifetime cancer risk (ELCR) values are (0.47, 0.72 and 0.77) x10−3 respectively. The results obtained in the cities indicate that the BIR levels, and corresponding estimated health risk parameters in Koko > Oghara > Sapele. The estimated effective dosage to organs shows that liver receiving the least dose of 0.07mSvy−1 (11%) while testes got the highest dose of 0.12 mSvy−1 (19%). The overall results obtained show that all the thirteen zones’ BIR levels and their estimated risk parameters exceeded their recommended limits for the public and were also higher than reported values in previous studies reviewed. The reported significant elevation of the obtained background ionizing radiation (BIR) values may not necessarily establish any immediate likelihood of radiological health risk, but call for caution on possible accumulative radiation effects in future on the residents of the study area.

Ensuring radiation safety: Evaluating dose and compliance among medical staff at King Faisal Medical Complex, Saudi Arabia

BackgroundRadiation is an integral part of routine medical practice, but it carries a risk to the health of medical staff. Hence, it should be assessed periodically. The study's goal was to quantify the levels of radiation exposure for medical staff at King Faisal Medical Complex (KFMC), Taif City Saudi Arabia, and to assess their radiation protective procedures in practice. MethodsThe study looked at the thermoluminescence dosimeters (TLDs) records of 50 medical professionals who were exposed to radiation while working at KFMC from 2019 to 2020 in Taif city, Saudi Arabia. In Riyadh, radiation exposure is read from skin TLDs using Harshaw model 6600 plus detectors. The Excel software was utilized to process the obtained data for calculating effective doses. A questionnaire was also distributed to the medical staff to assess their radiation protection procedures. The Statistical Package for Social Sciences (SPSS) program version 23 was used to analyze the obtained data. ResultsThe mean annual effective doses of the medical staff in 2019 and 2020 were determined to be 1.14 mSv and 1.4645 mSv, respectively, with no significant difference in effective doses between males and females in either year. The socio-demographic features of the medical personnel were examined, and the findings revealed that the majority of participants were male radiological technologists. The rate of adherence to radiation protection techniques was 68%, with a normally distributed dispersal. The amount of adherence varied significantly depending on nationality, occupation, and academic qualification. ConclusionAccording to the research, the mean annual effective dosage for medical professionals at KFMC was significantly below the recommended level, indicating satisfactory compliance with the ALARA radiation safety concept.

Exploring tectonic sites with radon from groundwater sources and dose evaluation in various age groups in Baramulla, J&K, India

Maintaining water quality is essential to protect human health from elevated levels of radon, a water-soluble radioactive gas that can pose serious risks when levels are above safe thresholds. This study evaluated the radon levels in groundwater sources in the Baramulla district of Jammu and Kashmir using a scintillation-based smart RnDuo detector. The levels of radon showed significant fluctuations, ranging from 19 ± 0.7 to 93 ± 1.5 Bq L−1, with an arithmetic mean of 41.3 ± 1.0 Bq L−1. Notably, 51 % of the samples exceeded the limits set by USEPA (11 Bq L−1) and UNSCEAR (40 Bq L−1), yet all of them remained below the WHO's guideline of 100 Bq L−1. Furthermore, 13 % of the samples exceed 60 Bq L−1. Annual inhalation and ingestion doses vary across age groups surpassing the WHO recommendations for drinking water quality but lying below the UNSCEAR 1000 μSv y−1 suggested levels. Importantly, the mean annual effective dose throughout all age groups falls well below the ICRP range (3–10 mSv y−1). The analysis suggested that radon exposure could lead to 0.52 to 3 excess cancer cases per thousand people, with average values for all age groups remaining less than the permitted value of 1.45 × 10−3 as suggested by UNSCEAR. The study also explores physiochemical parameters, aiding future epidemiological studies and fault investigations.

Long-term monitoring of outdoor natural gamma absorbed dose rate in air in Bengaluru, Karnataka, India.

This research forms a part of the comprehensive Indian Environmental Radiation Monitoring Network program, focusing on the continuous measurement of absorbed dose rate in outdoor air due to natural gamma radiation (cosmic and terrestrial) in Bengaluru, Karnataka, India. Over the course of a decade (2013-2023), data were collected from 41 monitoring locations in the city using permanently field-installed Geiger-Mueller detector-based environmental radiation monitors. This paper presents an analysis of the extensive long-term monitoring results. The mean absorbed gamma dose rate in outdoor air across the monitoring locations ranged from 84±9 to 156±4 nGy.h-1, with a calculated mean value of 124±15 nGy.h-1. The estimated mean annual effective dose due to outdoor natural gamma radiation varied from 0.10±0.01 to 0.19±0.01mSv.y-1, with an overall mean of 0.15±0.02mSv.y-1.

Assessment of Outdoor Background Radiation Level and its Radiological Hazards at Jimeta and Yola Towns of Adamawa State, Nigeria

The radiation from different types of radionuclides has both advantages and disadvantages. However, detailed research reveals that the drawbacks of several radionuclides far outweigh their advantages, particularly in regions with high concentrations, posing alarming impacts on human health. The study focuses on assessing outdoor background radiation levels in Jimeta and Yola towns, Adamawa State, Nigeria. Using a well-calibrated portable halogen-quenched Geiger Muller (GM) detector at 20 locations, measurements were taken at an elevation of 1.0m above ground level, with GPS tracking for accurate location. The research evaluates radiological health hazards and radiation effective doses to different body organs based on outdoor background exposure rates. Comparison with recommended permissible limits reveals that mean values for outdoor background exposure levels (0.016 mRh-1) and absorbed dose rates (147.46 nGyh-1) exceed safety limits (0.013 mRh-1, 84.0 nGyh-1) set by UNSCEAR and ICRP. The total excessive lifetime cancer risk (ELCR) ranged from 0.33× 10−3 to 2.61× 10−3 , with a mean value of 0.78 × 10−3 , close to the world average lifetime cancer limit (1.45× 10−3 ). Despite the mean annual effective dose equivalent (AEDE) (0.2219mSvy-1) being below the recommended limit of 1.00 mSvy-1 for general public exposure, and effective doses to various body organs remaining below 1.0 mSvy-1, the study indicates potential long-term health hazards such as cancer due to accumulated doses. Generally, the study shows that Jimeta and Yola Metroplis is relatively safe radiologically with little contamination which could be attributed to the geological formation and partly due to human activity such as market and car park for transport system in the area. However, the contamination will not pose any immediate radiological health effect on resident of the area but there is tendency for long –term health hazards in the future such as cancer due to doses accumulated. It is therefore recommended that regular radiation monitoring exercise should be conducted on the area from time to time in order to checkmate both the workers and the members of public from high radiation exposure.

Risk assessment of radon exposure inside residential dwellings in Safi city, Morocco

ABSTRACT A radon study was conducted in 50 residences in Safi city, Morocco, using LR-115 detectors. The annual effective dose and Excess Lifetime Cancer Risk were also estimated. The measured radon concentrations ranged between the Lower Limit of Detection (LLD) and 132 Bq.m−3 with an arithmetic mean of 53 Bq.m−3 and a geometric mean of 41 Bq.m−3 (2.32). The results indicated that 58% of the obtained values exceeded the worldwide average value (39 Bq.m−3). In addition, the results revealed significant impacts of floor level and region on indoor radon levels. Inhabitants of the surveyed houses were found to receive a mean annual effective dose of 1.5 ± 0.1 mSv.y−1, corresponding to an Excess Lifetime Cancer Risk of 0.6%. Importantly, all annual effective dose values were below the recommended action level by the ICRP (3–10 mSv.y−1). Using the Ordinary Kriging method implemented in the QGIS software, an indoor radon map was created based on the collected data. The findings in this study serve as baseline values for future studies concerning radon concentrations and their fluctuations.

Assessment of the Occupational Radiation Exposure of Anesthesia Staff in Interventional Cardiology.

This research seeks to evaluate the occupational radiation dose, quantified as the whole-body Annual Mean Effective Dose (AMED), received by anesthesia personnel in interventional cardiology. Thermoluminescent dosimetry data was collected over five years (2019-2023) for a total of 175 anesthesia staff. Technologists comprised approximately 72.4% of the participants (55% male and 45% female), while consultants accounted for 27.6% (70% male and 30% female). Statistical tests, including Independent Samples T-Test and One-Way ANOVA, compared AMED across genders, job titles, and years. The study's findings on AMED across all staff from 2019 to 2023 showed marked variability in AMED. There was a significant rise in AMED from 0.72 mSv in 2019 to 0.92 mSv in 2020, then a decline to 0.82 mSv in 2021, with further decreases to 0.67 mSv in 2022 and finally to 0.65 mSv in 2023 (p < 0.001). The average AMED over the five-year span (2019-2023) was 0.76 ± 0.4 mSv. In terms of gender, the overall AMED for males was 0.73 ± 0.36 mSv and for females 0.79 ± 0.45 mSv, showing no significant statistical difference (p = 0.272). Significant differences in exposure were observed between the technologists who experienced a higher overall AMED (0.8 ± 0.43 mSv) compared to consultants (0.63 ± 0.29 mSv, p = 0.008). Despite these variations, AMED values remained lower than the annual occupational dose limit of 20 mSv, indicating generally low radiation exposure for anesthesia staff. This study emphasizes the importance of ongoing monitoring and enhanced protective measures to safeguard the health of medical professionals working with radiation.

Evaluation of Radioactivity Levels in Soil Samples from Assosa City in Benishangul Gumuz Region, Ethiopia

The specific activity concentrations of naturally occurring radionuclides in soil samples collected from suburban areas of Assosa City was measured using a High purity Germanium (HPGe) detector. The average specific activity concentrations of 238U and 232Th exceed the recommended safe value of 35.0 and 30.0 Bq kg−1, respectively. For 40K, the average activity concentration is below the recommended safe value of 400.0 Bq kg−1. The calculated mean value of the absorbed dose rate is 72.8 ± 3.72 nGy h−1 which exceed the recommended safe value of 59 nGy h−1. The calculated mean annual effective dose equivalent values for indoor and outdoor are 2.11 ± 0.1 mSv y−1 and 0.52 ± 0.02 mSv y−1, respectively. The calculated mean values of the internal hazard index, external hazard index, and gamma index are 0.43 ± 0.013, 0.56 ± 0.01, and 0.5 ± 0.01, respectively, and those values are below the recommended safe value of one. The mean value of excessive lifetime cancer risk is above the threshold value of 0.29 × 10−3. From this study, it is recommended that Assosa soil needs further investigations.

Assessment of natural radioactivity levels and potential radiological risks of commonly used building materials in Uttara Kannada District, Karnataka, India.

The main goal of this study is to evaluate the natural radioactivity and potential radiological risks of frequently used building materials in Uttara Kannada district. Using an High purity Germanium Detector (HPGe) detector-based gamma-ray spectrometer, the activity concentration of 226Ra, 232Th and 40K was determined. The activity concentration of 226Ra, 232Th and 40K in the construction materials vary from 13.78±0.90 to 151.9±1.85, 14.21±0.80 to 207.72±2.9 and 55.26±1.20 to 1298.24±25Bqkg-1 with an average value of 40.57±1.37,60.13±1.70 and 425.38±4.75Bqkg-1 having a geometric mean of 33.07, 46.49 and 290.20Bqkg-1, respectively. The mean annual effective dose equivalent was found to be 0.68mSv y-1 and is less than the International Commission on Radiological Protection proposed acceptable limit of 1mSv y-1. The estimated radiological hazard parameters show that these building materials are safe to use in the construction of homes and do not offer a substantial source of radiation hazard.

Natural radionuclide distribution and analysis of associated radiological concerns in rock samples from a rocky town (Dutsin-Ma) in the North-Western region of Nigeria

Natural radionuclides in rock samples, especially 226Ra (Radon), 232Th (thorium), and 40K (potassium), are the primary source of exposure to radiation for employees and the public, and their detection is critical for radiation safety. The gamma (γ) radiation from natural radionuclides was quantified using the γ-ray spectrometry method in twenty rock samples obtained from Dutsin-Ma, a rocky town in Nigeria's north-western region. The data obtained were used to estimate the radiological parameters and the excess lifetime cancer risk (ELCR). The results obtained show that the minimum activity concentrations of 40K, 232Th, and 226Ra are respectively 36.7 Bq/kg, 25.99 Bq/kg, and 11.59 Bq/kg, with their maximum values being 73.23 Bq/kg, 92.81 Bq/kg and 100.93 Bq/kg respectively. The average activity of 40K, 232Th, and 226Ra in the rock samples were found to be 73.5781±3.38 Bq/kg, 40.7848±3.32 Bq/kg, and 33.6616±3.58 Bq/kg respectively, which were all below the World average values of (33, 45 and 420) Bq/kg respectively. The ELCR was found to be 0.185±0.01, while the average absorbed dose rate, as well as the mean annual effective dose rate, were calculated to be 43.13±2.7 nGy/h and 0.015±0.003 mSv/y respectively. The outcomes for internal hazard, external hazard, annual absorbed and effective dose equivalent (ABEDE), alpha and gamma index values were below the maximum values allowed limits of 1 mSv/y for ABEDE and 1 for representative alpha &amp; gamma index values, internal and external hazards as recommended by the International Commission on Radiological Protection (ICRP). This study shows that the radiation contamination of rock particles in Dutsin-Ma LGA does not pose much significant risk.

Distribution of naturally occurring radionuclides and gamma dose rate assessment in the soils of high background natural radiation area Odisha, India.

A study on the activity concentration of primordial radionuclides 226Ra, 232Th and 40K was carried out on the surface soil samples collected from the coastal villages between Chhatrapur and Gopalpur regions of high background natural radiation area Odisha, India, using high purity germanium gamma spectroscopy. The mean activity concentrations of 226Ra, 232Th and 40K were found to be 231, 1692 and 250Bq/kg, respectively. The total mean absorbed dose owing to the presence of 226Ra, 232Th and 40K was 1139nGy/h. The mean annual effective dose was found to be 1397μSv/y and higher than the UNSCEAR average value 70μSv/y.