Annual Gonadal Dose Equivalent Research Articles

Natural Radionuclides Concentrations and Associated Radiation Hazard of Some Building Rocks Used in Taiz City, Yemen

Building materials comprise a diverse range of natural rocks that contain varying mineral components including radionuclides. Gamma spectrometry-based high-purity Germanium detectors were utilized to measure the activity concentrations of natural radionuclides: Radium-226 (226Ra), Thorium-232 (232Th), and Potassium-40 (40K) in various building rock samples found within and surrounding Taiz city. The activity concentrations of 226Ra, 232Th, and 40K vary from 27.79 ± 0.77 to 234.49 ± 3.13 Bq.kg-1, 25.82 ± 0.40 to 415.31 ± 2.47 Bq.kg-1, and 457.91±2.61 to 1139.56 ± 5.43 Bq.kg-1 with overall average value of 71.55 Bq.kg-1, 93.87 Bq.kg-1, 966.88 Bq.kg-1 respectively, these values were higher than the permissible thresholds. Furthermore, several radiation hazard indices were estimated including the radium equivalent (Raeq), the external hazard index (Hex), the internal hazard index (Hin), the gamma level index (Iɤ), the dose rate(Dɤ), the annual effective dose equivalent (AEDE), the excess lifetime cancer risk (ELCR), and the annual gonadal dose equivalent (AGDE). The findings illustrated that Basalt rocks have the minimum values of radiation hazard indices while the Himatite rocks have the maximum values of radiation hazard. The average values of radiation risks for most of building rocks fall below the recommended limits for safety. Based on the Radiation hazard indices of building rock samples, it can be concluded that with the exception of hematite rocks, all the examined rocks are considered safe for use in construction materials and pose non-significant radiation risks. The awareness about natural radioactivity levels of building rocks is critical for planning and performing strategies in radiation safety of buildings.

Assessment of radionuclides in the soil of Bonny Local Government Area Of Rivers State, Nigeria and evaluation of radiological risk

Twenty Samples each of soil from Bonny LGA, Rivers State, Nigeria were analyzed using NaI(IT) gamma detector to estimate radiation hazard due to the anthropogenic sources. The activity concentration of 232Th was found to be in the range 18.78 – 397.13 BqKg-1, 40K in the range 43.72 – 390.62 BqKg-1 and 226Ra in the range 10.77 – 57.84 BqKg-1 all in soil. These results were used to calculate the radiological hazard parameters including the Annual Gonadal Equivalent Dose. The calculated gamma exposure rates ranged between 10.00 – 270.79 nGyh-1 while the average value of the Excess Lifetime Cancer Risk (ELCR) was found to be 0.38 x 10-3 for soil which is higher than the world average of 0.29 x 10-3.

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

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

Assessment of 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.

ASSESSING ANNUAL EXPOSURES DOSE AND OTHER RADIOLOGICAL PARAMETERS FROM COSMIC RADIATION AMONG FLIGHT CREWS IN NIGERIA LOCAL AIRLINE

Cosmic radiation is high-energy radiation generated in outer space that increases with altitudes. This study uses aircrew cosmic radiation exposure to measure radiation dose received by monitoring individual crew members (a total of 179 members for all the crews in the three routes for 2011 to 2022) using computer model calculator (CARI – 6M) on Nigeria’s local airlines crews and evaluated other radiological parameters. The finding shows that annual effective dose (AED) received by the air crew members between 2011 and 2022 across the three routes (Lagos – Kano, Lagos – Abuja and Lagos – Port Harcourt) ranges between 0.230 and 1.90 µSv y-1 and there is a direct relationship between the time of flight and the effective dose received by the crew members. This result is lower than the recommended value of 20 µSv y-1 by International bodies. The result also revealed that Annual Gonadal Dose Equivalent (AGDE) across the three routes ranges from 7.20 – 380 µSv y-1 with only Lagos – Kano route in year 2017 (380 µSv y-1) were above the maximum permissible value of 300 µSv y-1. The findings indicated low AED however; the significant excess lifetime cancer risk that increases with cumulative doses and dependent of the flight route constitute a risk. This implies that, there are possibilities of the crew members developing cancer during their lifetime. It’s therefore recommended that Nigerian Civil Aviation Authority should introduce regulations and training program to reduce potential sources of radiation exposure of Nigerian flight crews.

Radioactivity of inert construction and demolition waste from Hong Kong and environmental assessment for marine trial reclamation in Guanghai Bay

Inert construction and demolition waste from Hong Kong (HK public fills) has been used for marine trial reclamation in the Guanghai Bay (GHWT) of the Chinese Mainland. However, an environmental assessment of HK public fills is necessary due to higher radioactivity in HK soils than typical global levels. Here, radiation dose rate, gamma radionuclides and gross beta of HK public fills were analyzed. The origin information was explored using natural primordial radionuclides as fingerprints. Our data show that radiation dose rate of HK public fills before disposal was 0.14–0.54 (0.33 ± 0.03) μSv/h (n = 16,722 data with 2787 ships) in 2014, which is less than the GHWT background. Monthly detection of 238U, 226Ra, 210Pb, 232Th, 228Th, 40K, and gross beta in HK public fills was conducted on three random ships. Their specific activities were <6.27–155.5, 58.7–98.7, <7.83–238.2,97.9–168.6, 87.1–136.0, 463.1–1,018, and 1047–1658 Bq/kgDW, respectively. These results suggest that the radioactivity levels of HK public fills are essentially the same as the GHWT background. The study assessed potential risks using various indices icluding Raeq (Radium equivalent activity), Hex (External radiation hazard index), Hin (Internal radiation hazard index), Iγ (Gamma index), AUI (Activity utilization index), AUI (Activity utilization index), E (Annual effective dose), AGDE (Annual gonadal dose equivalent), RLI (Representative level index), Din (Indoor air absorbed dose rate), Dout (Outdoor air absorbed dose rate), and ELCR (Excess lifetime cancer risk). The study suggests that HK public fills should be used for the trial reclamation rather than building-house materials. This provides valuable insights for the resource utilization and minimizing environmental pollution of HK public fills. The aim is to offer fundamental technical assistance for future waste resource utilization, ecological protection, and restoration in the Guangdong-Hong Kong-Macao Greater Bay Area.

NATURALLY OCCURRING RADIONUCLIDES AND THEIR RADIOLOGICAL RISK ASSESSMENT IN RIVER SEDIMENTS FROM THE DITRAU ALKALINE MASSIF

Naturally occurring 238U, 232Th and 40K radionuclides within river bed sediments of Jolotca and Ditrău rivers from Ditrău Alkaline Massif (DAM) and their environmental risk and spatial distribution have been analyzed. The DAM metamorphic formations have been the subject of multiple studies due to their structure and high variety of mineral species. This led to the execution of many mining operations. River bed sediment samples have been collected from two of the main drainage basins of DAM, Ditrău and Jolotca rivers. The samples were analyzed using gamma-ray spectrometry in order to determine the concentration of the naturally occurring radionuclides and the risk parameters such as RLI (Representative level index), AGDE (Annual gonadal dose equivalent), Hex (External hazard index), Hin (Internal hazard index) and DR (absorbed gamma dose rates in air). 238U, 232Th and 40K show values higher than the Upper Continental Crust (UCC) and other studies from around the world. DR, AGDE and RLI are higher than the global average and the safe limits. These values are a consequence of the geological context which determined the presence of heavy minerals and Th and U bearing minerals.

Gamma Ray Spectroscopy Analysis of Sediments of Coastal Areas in Ennore, Tamil Nadu

Objectives: This research focuses on the determination of the natural radionuclides radium, thorium, and potassium in the twenty-six sediment samples collected at the sea, beach, and creek regions of Ennore Port. Methods: The activity concentrations of 226Ra, 232Th, and 40K were determined using gamma ray spectrometry with a high-purity germanium (HPGe) detector. Findings: The average activity concentrations of 226Ra, 232Th, and 40K were in the descending order of 40K (397.58 Bq kg-1) &gt; 232Th (65.83 Bq kg-1) &gt; 226Ra (18.28 Bq kg-1). The estimated average values of radiological parameters such as radium equivalent activity (143.04 Bq kg-1), absorbed dose rate (64.91 nGy h-1), annual effective dose equivalent (0.32 mSv y-1), and external hazard index (0.39) were lower than the respective world average values, reported by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000). Moreover, the representative level index and annual gonadal dose equivalent were slightly higher than the world average value. Hence, this research proved that the study area is radiologically safe for humans and the environment. Novelty: A location and sample collection-based novelty is approached to carried out the work. Sea sediments were also collected along with samples from creek and beach regions in order to examine the dispersion of natural radionuclides from land to marine environments. The samples from the beach and creek regions were collected using a Peterson grab sampler. Especially in the sea region, the samples were collected using a Van Veen grab sampler at a depth of 4 m and a distance of 10 m parallel to the shoreline. Keywords: Natural radioactivity, Sediment, Ennore, Gamma ray spectrometry, HPGe detector, Radiological parameters

Geochemical Distribution and Environmental Risks of Radionuclides in Soils and Sediments Runoff of a Uranium Mining Area in South China.

Uranium mining activities have contributed to the distribution and uptake of radionuclides, which have increased the active concentrations of natural radionuclides in environmental media, causing elevated human health risks. The present study aims to assess the spatial distribution characteristics of natural radionuclides in the surface soils and river sediments of the typical granite uranium mining area in South China, as well as investigate the geochemical features of natural radionuclides in the soil and sediments to understand their migration processes. The activity concentrations for 238U, 226Ra, 232Th, and 40K ranged from 17-3925 Bq/kg, 50-1180 Bq/kg, 29-459 Bq/kg, and 240-1890 Bq/kg, respectively. The open-pit mining areas and tailings pond locations exhibited the highest concentrations of activity for all these radionuclides. This distribution points to an elevated potential health risk due to radiological exposure in these specific areas. Additionally, the values of radium equivalent activity (Raeq) and annual gonadal dose equivalent (AGDE) in those areas were higher than the limits recommended by ICRP (2021). 238U and 226Ra have a significant correlation (0.724), and the cluster analysis was showing a statistically meaningful cluster below 5 indicated that they have similar behavior during parent rock weathering and watershed erosion, and the distribution of 232Th and 40K were influenced by the addition of rock types. The activity ratios of 226Ra/238U, 226Ra/232Th, 238U/40K, and 226Ra/40K variation indicated that 40K more mobile than 226Ra and 238U, U(VI) was reduced to U(IV) by organic matter in the downstream area and re-entered into the sediment during the sediment surface runoff in the small watershed of the uranium ore open-pit mining area. Therefore, it is necessary to further seal up and repair the tailings landfill area.

Investigation of natural radioactivity in soil of selected hospitals in Imo State, Nigeria

We measured the terrestrial activity contents, radiation doses; hazard indices and excessive lifetime cancer risk (ELCR) from primordial radionuclides (226Ra, 232Th and 40K) in 50 soil samples collected from the five selected hospitals within Imo State, Nigeria. Radioactivity measurements were carried out by the method of gamma-ray spectrometry with thallium doped sodium iodide [NaI(Tl)] detector. The mean activity values obtained for the radionuclides 226Ra, 232Th and 40K (respectively) in Federal Medical Centre, Owerri (FMC); General Hospital, Umuguma, Owerri West, (GHW); Neuroscience Hospital, Ohaji Egbema (NHO); St. Joseph Hospital, Okigwe (SJH); Imo State University Teaching Hospital, Orlu (IMSUTH) are: 20.56±4.73, 14.96±3.42 and 105.65±31.40 Bqkg-1; 11.77±3.03, 17.45±4.20 and 63.67±18.44 Bqkg-1; 17.97±4.65,10.02±2.18 and 190.43±42.83 Bqkg-1; 11.36±3.71, 17.39±4.46 and 76.29±25.08 Bqkg-1; and 11.84±3.64, 4.89±2.25 and 165.18±58.41 Bqkg-1 respectively. These values were below the worldwide average values: 32 Bqkg-1 for 226Ra, 45 Bqkg-1 for 232Th, and 412 Bqkg-1 for 40K as documented by UNSCEAR (2000). 40K recorded the highest mean activity compared to 226Ra and 232Th in the studied soil samples. Radium equivalent activity (Raeq), absorbed gamma dose rate (Dr), annual effective dose equivalent (AEDE), external hazard index (Hex), gamma representative index (Ιϒr) and annual gonadal dose equivalent (AGDE), were calculated to quantify the radiation risk to the public from exposure to 226Ra, 232Th and 40K in the studied samples. In addition, excess lifetime cancer risk (ELCR) was also accessed. The mean computed values of the excess lifetime cancer risk for FMC, GHW, NHO, SJH and IMSUTH are 0.08±0.03, 0.09±0.15, 0.10±0.2, 0.10±0.03 and 0.07±0.02 respectively. The mean values of these hazard parameters were within the acceptable safety limits provided for human safety and environmental protection.

Radioactivity of 226Ra, 232Th and 40K in soil in Northwest part of Turkey: assessment of radiological impacts

Abstract The surface soil samples were collected from Northwest Turkey. The activity concentrations of 226Ra, 232Th, and 40K were measured using an HPGe gamma-spectroscopy system. The activity concentrations of 226Ra, 232Th, and 40K in the soils were found to be in the range of 11.78 ± 1.12–43.89 ± 14.94, 3.19 ± 2.01–88.22 ± 0.92, 362.81 ± 5.94–829.27 ± 12.38 Bq kg−1 d.w., respectively. The Surfer program was used to obtain 3-dimensional maps of the specific activities. Radium Equivalent Activity (Raeq), Absorbed Gamma Dose Rate (D), Annual Effective Dose Equivalent (AEDE), The Excess Life Time Cancer Risk (ELCR), External (H ex) and Internal (H in) Hazard Indexes, Annual Gonadal Dose Equivalent (AGDE), and Activity Utilization Index (AUI) were calculated and compared with the recommended values. Pearson’s correlation analysis (PCA) and factor analysis (FA) were utilized to analyze the data and indicate between the radiological parameters. The analysis showed that the total radiation was mainly caused by 226Ra and 232Th.

Evaluation of Chemical and Impacts of Radionuclides in Borehole Waters in Igbajo Town, Osun State, Nigeria

Water is a universal solvent on earth and sources such as wells, rivers, springs, boreholes, and other freshwater bodies typically serve as a pathway for contaminants to enter the ecosystem while also supplying water for domestic and drinking purposes. The activity concentrations of radionuclides in borehole water in Igbajo town were assessed using gamma-ray spectroscopy, so as to effectively determine the degree of radiological risk to the environment and its inhabitants, the outcomes were used to calculate all the radiological impact parameters. The activity concentrations obtained for 40K, 238U and 232Thranged from 7.25±0.60 to 62.15±4.48Bq.L–1; 3.08±0.45 to 15.24±3.07 Bq.L–1and 1.08±1.10 to 17.75±1.59 Bq.L–1 and with average values of 23.12±1.59 Bq.L–1, 6.27±2.01 Bq.L–1 and 7.01±0.89 Bq.L–1 respectively. The Annual Effective Dose (AED) for ingested radionuclide in drinking water for an adult was1.4872 μSv.yr–1. The Radium Equivalent Activity Index, Raeq obtained was 34.9186 Bq.L–1. The estimated hazard indices Hint and Hext were 0.04876 and 0.06574 respectively. The Excess Lifetime Cancer Risk, ELCR (x10–6) was 5205.15. With a lifetime expectancy of 70 years, this high value suggests that there is a high chance of developing cancer.The value of the Annual Gonadal Equivalent Dose, AGED in the water was 55.9175μSv.yr–1. The estimated Gamma Index, Iγ was0.1273 mSv.yr–1. There is a significant health hazard to the environment and people living in the area owing to the radioactivity contents and radiological impact parameters. Hence, the need for urgent attention and means to prevent hazards which the overdose could cause.

Determination of radiation hazard indices (Annual Gonadal Dose Equivalent) in water samples in the vicinity of mining site in Minna, Niger State, Nigeria

The gross alpha and beta radionuclide activity of source of water from mining site in Minna, Niger state has been carried out. Eleven water samples were collected from the farming, residential/commercial, and industrial zones in the community and were analyzed using the protean instrument corporation (PIC) MPC 2000DP, single channel proportional counters. Annual Gonadal Dose Equivalent (AGDE) was determined. AGDE α and β 20.254399/3.088977mSv/y. This shows that the calculated values of alpha in BHL3 are above the accepted value for ICRP. Moreover, the calculated values of beta in BHL1 are above the accepted value for ICRP. It can be observed that all the remaining values for alpha and beta are below the ICRP values of 0.5Bq/L for alpha and 1Bq/L for beta.

Assessment of natural and anthropogenic radioactivity levels and their radiological hazards in surface soil samples around oil refinery, Little Aden City, Yemen

The activity concentration of global fallout of 137Cs and naturally- occurring radioactive materials (NORM), which primarily due to the geological and geographical condition of soil. and maybe occur from oil and gas burring processes and consequently accumulate on surface soil around the oil refinery in Aden Assoghra city, Yemen were studied by use the gamma-ray spectrometer equipped with a high purity germanium (HPGe) detector and specially designed shield. The average concentrations of 226Ra, 232Th, and 40K expressed in (Bq kg−1) of the studied samples were (13 ± 0.44) Bq kg−1, (22.1 ± 0.64) Bq kg−1 and (509 ± 9) Bq kg−1, respectively. Low concentrations of 137Cs were noted from some sample in the study area, where ranged from (0.3 ± 0.2) to (1.7 ± 0.2) Bq kg-1. The average values of calculated radiological hazard indices were 40.6 nGy h−1 (absorbed dose rate outdoors), 0.05 mSv y−1 (annual effective dose outdoors), 0.279 mSv y−1 (annual effective dose indoors), 83.7 Bq kg−1 (radium equivalent), 0.23 (external hazard index), 0.26 (internal hazard index), 0.65 (representative level index), 0.174×10-3 (the excess lifetime cancer risk ELCR) and 0.292mSv y−1 (annual gonadal equivalent dose, AGED).

Assessment of Radionuclide Concentrations in Oil Producing Communities in Bayelsa West Senatorial District, Bayelsa State, Nigeria

An assessment of radionuclide concentration in oil producing areas in Bayelsa West Senatorial District, Bayelsa State have been evaluated. In this study, a total of twenty five (25) soil, samples were collected for laboratory analysis. The survey was achieved using a factory calibrated Gamma Scout radiation meter and a Gamma Spectroscopy with Sodium Iodide (NA(TI) Detector used for counting and detection of radionuclide contentration of all samples. The results obtained in the study showed that the average concentrations for 40 K, 238 U and 232 Th in soil samples are valued at 520.888 ± 134.119 ???? ?1 , 18.495 ± 4.983 ???? ?1 and 11.463 ± 2.472 ???? ?1 respectively. The ?? ?? has an average value of 74.675 ± 16.934 ???? ?1 . The ? ?? has an average value of 0.21 ± 0.049 while the average value of ? ?? is 0.26 ± 0.064 which falls below the permissible level. The absorbed dose rate (D) due to 40 K, 238 U and 232 Th in soil samples has an average of 37.23 ± 8.692 ???? ?1 . This was also below the world average of 60???? ?1 . Annual effective dose equivalent (AEDE) has an average value of 45.66 ± 10.654 µ??? ?1 . This was also below the world average value. Annual Gonadal Equivalent Dose (AGED) and Representative Gamma Index (? ? ) were valued at 269.13 ± 63.095 ???? ?1 and 0.59 ± 0.117 respectively. Generally, the obtained value of 40 K was higher than the permissible level while 238 U and 232 Th where lower than the recommended standard value of 400 ???? ?1 , 33 ???? ?1 and 35 ???? ?1 (UNSCEAR, 2000). Therefore, the use of the soil for industrial and domestic poses no radiological threat to human health.

Radionuclide concentrations in agricultural soil and lifetime cancer risk due to gamma radioactivity in district Swabi, KPK, Pakistan

This study focuses on measuring the levels of naturally occurring radioactivity in the soil of Swabi, Khyber Pakhtunkhwa, Pakistan, as well as the associated health hazard. Thirty (30) soil samples were collected from various locations and analyzed for 226Ra, 232Th, and 40K radioactivity levels using a High Purity Germanium detector (HPGe) gamma-ray spectrometer with a photo-peak efficiency of approximately 52.3%. The average values obtained for these radionuclides are 35.6 ± 5.7 Bqkg−1, 47 ± 12.5 Bqkg−1, and 877 ± 153 Bqkg−1, respectively. The level of 232Th is slightly higher and 40K is 2.2 times higher than the internationally recommended limit of 30 Bqkg−1 and 400 Bqkg−1, respectively. Various parameters were calculated based on the results obtained, including Radium Equivalent (Raeq), External Hazard (Hex), Absorbed Dose Rate (D), Annual Gonadal Equivalent Dose (AGDE), Annual Effective Dose Rate, and Excess Lifetime Cancer Risk (ELCR), which are 170.3 ± 24 Bqkg−1, 0.46 ± 0.06 Bqkg−1, 81.4 ± 2.04 nGy h−1, 582 ± 78.08 μSvy−1, 99.8 ± 13.5 μSv Gy−1, and 0.349 ± 0.04, respectively. These values are below the limits recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) in 2002. This study highlights the potential radiation threats associated with natural radioactivity levels in the soil of Swabi and provides valuable information for public health and safety.

Estimation of Annual Gonadal Dose Equivalent in Some Livestock Food in Libyan Markets

In the present study, the concentrations of 226Ra, 232Th, 238U, and 40K in 10 different samples of foodstuff are investigated using a gamma spectrometer with a Sodium iodide detector NaI(TI). The results indicated that the concentration of 226Ra, 232Th, 238U, and 40K in the samples ranged from (19.14 to 99.79) Bq/kg for radium, the activity concentration of Thorium ranged from (31.09 to 124.93) Bq/kg, the activity concentration of uranium ranged from (24.86 to 103.01) Bq/kg and the activity concentration of potassium ranged from (101.83 to 480.92) Bq/Kg. The results indicated that the annual gonadal dose equivalent (AGDE) of 226Ra, 232Th, and 40K in the samples were higher than the permissible level (0.3mSv/y), except samples (S3, S5, S8).

Effect of Grain Size on Radionuclide Content in Sediment Samples from Kolo Creek, Bayelsa State, Nigeria

The effect of grain sizes on radionuclide concentration in soil and sediment samples from Kolo creek, Bayelsa State was investigated using gamma spectroscopy. Eight (8) samples of sediment were collected around the oil spill site of the creek. All the samples were separated into four different grain sizes, A (0.5mm), B (1mm), C (1.5mm) and D (2mm), making a total of 32 sediment. The activity concentration in sediment samples of grain sizes 0.5 mm, 1.0mm, 1.5mm and 2mm were determined. In sediment samples of grain sizes 0.5mm(A), the activity concentration of 226Ra , 232Th and 40K ranges from 2.24 to 20.032.43Bq/kg, 3.21 to 5.591.32 Bq/kg and 24.46 4.06 to 795.99 6.20 Bq/kg respectively. For grain size of 1.0mm (B) the activity concentration of 226Ra, 232Th and 40K varies from 2.661.30 to 26.64Bq/kg, 2.19 0.95 to 33.47 Bq/kg and 43.38 to 739.21Bq/kg respectively. For grain size of 1.5mm (C) the activity concentration of 226Ra, 232Th and 40K varies from 4.401.09 to 33.93± 3.65 Bq/kg, 2.14±1.72 to 26.15±5.3 Bq/kg and 39.90±3.54 to 471.36±6.12 Bq/kg respectively. For grain size of 2.0 mm (D) the activity concentration of 226Ra, 232Th and 40K varies from 4.81±1.84 to 40.29±2.50 Bq/kg, 2.19±1.40 to 83.20±3.90 Bq/kg and 39.01 ±4.00 to 497.56±5.87Bq/kg respectively. The result obtained shows there was no clear trend in variation of activity concentration with grain sizes. The mean values obtained are below the world average of 35, 30 and 400 Bq/kg for 226 Ra, 232Th and 40K for grain sizes of 0.5, 1.0, 1.5 and 2.0 mm respectively in all the communities except samples from Kolo that recorded 471.36±6.12 to 795.99±6.44 Bq/kg in all the grain sizes. Radiological risk parameters such as Absorbed Dose Rate, Annual Effective Dose Equivalent, Annual Gonadal Dose Equivalent, Annual Utility Index, Radioactivity Level Index, Hazard Indices and Excess Life Cancer Risk were estimated and values were found to be within the word average. From this study, the sediment of the given grain sizes will pose no radiological health risk if used in farming and in building construction.

Assessment of radiation hazard indices due to naturally occurring long-life radionuclides in the coastal area of Barra de Valizas, Uruguay.

The Uruguayan east coast has several mineral resources, which include black sand ores in the Barra de Valizas-Aguas Dulces area. Cancer in Uruguay shows non-homogeneous geographical distribution, with the highest standardized mortality ratio (SMR) in the northeast and east region, which includes the aforementioned area and the town of Barra de Valizas. The activity concentration of natural radionuclides (226Ra, 232Th and 40K) in Barra de Valizas´soil was determined by gamma spectrometry in order to evaluate the radiological hazard for inhabitants and tourists. The outdoor annual effective dose (AEDE), excess lifetime cancer risk (ELCR), and annual gonadal dose equivalent (AGDE) were evaluated for inhabitants with a life expectancy of 77.7years, a 0.2 and 0.5 occupancy factor, and using the conversion coefficients recommended by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The annual effective dose was also evaluated for both summer and fortnight tourists. The radiological hazard indices for Barra de Valizas inhabitants are higher than the worldwide mean and recommended values. This may contribute to Rocha's higher SRM value, although a direct correlation cannot be assured with the epidemiological information currently available. Social, medical and anthropological studies will be carried out in future to provide data and verify this correlation.

Determination of Radionuclides Concentrations in Surface Soil Samples in the District of Bandirma, Balıkesir

Determination of the environmental radioactivity concentration value is very important as it directly effects human health. Natural and artificial radionuclide concentration levels have been determined by looking 226Ra, 232Th, 40K, and 137Cs radionuclides. In this study, natural and artificial continental radionuclide concentrations were measured in the Bandirma district of Balikesir. 226Ra, 232Th, 40K, and 137Cs radioactivity concentrations were detected with the aid of a high-purity germanium (HpGe) detector. Soil samples used in the study were selected from 30 different locations sampling points located in Bandirma. The radiological hazard indices such as absorbed gamma dose rate (D), annual gonadal dose equivalent (AGDE), exposure dose (ER), total annual effective dose (AED), excess lifetime cancer risk (ELCR), internal hazard index (Hin), external hazard index (Hex) and gamma representative level (GRL) were determined. The mean values of 226Ra, 232Th, 40K, and 137Cs concentrations in this study were 15.81 ± 1.35 Bq kg−1, 28.86 ± 1.07 Bq kg−1, 276.86 ± 11.69 Bq kg−1, and 1.98 ± 0.31 Bq kg−1 respectively. The calculated radiological hazard parameters were compared with the world averages. The obtained radioactivity concentration values were measured to be below the world average.