Determination of Activity Concentration of Natural Radionuclides and Radiation Hazards’ Assessment of Building Materials in High Background Radiation Areas of Homa and Ruri, Kenya

The areas around Homa and Ruri hills in Homa Bay County in Kenya are associated with high background radiation levels. The activity concentration of the natural radionuclides (226Ra, 232Th, and 40K) in earthen building materials used in the areas of Homa and Ruri hills has been measured using a NaI (Tl) detector in this work. The measured values of radioactivity concentrations are used to estimate the associated radiological risk. The earthen building material samples from Ruri registered relatively high 232Th concentration values averaging 1094 ± 55 Bq/kg, nearly three times those of the samples from Homa. 226Ra level was not significantly different in both regions with Homa reporting 129 ± 10 Bq/kg and Ruri 111 ± 6 Bq/kg. 40K was however higher in the samples from Homa by an approximate factor of 2 relative to those from Ruri where the activity concentration was 489 ± 24 Bq/kg. The radium equivalents for 226Ra, 232Th, and 40K in the samples from Ruri were 111 ± 9, 1564 ± 125, and 38 ± 3 Bq/kg, while in Homa, the values were 129 ± 10, 570 ± 46, and 69 ± 5 Bq/kg, respectively. The calculated value of total radium equivalent in Ruri was 1713 ± 137 Bq/kg which was two times higher than that of Homa. 232Th contributed about 74% and 91% to the total radium equivalent in Homa and Ruri, respectively; thus, it was the one with the largest contribution to radiation exposure in both regions. The average indoor annual effective dose rates were 1.74 ± 0.14 and 3.78 ± 0.30 mSv/y in Homa and Ruri, respectively, both of which were above the recommended safety limit of 1 mSv/y.

Study and Characterization of Natural Radioactivity Levels and Radiological Hazards of Soil in Wasit Governorate

In this paper studied and measured the natural radioactive for agricultural soil samples surrounding Kut as well as gardens, home, casinos and others. Eighteen samples of agricultural land were taken on three deep depths the first depth 10 cm and the second 20 cm and the third 30 cm. Twenty-five samples were taken from public parks, parks, casinos and other parks. They are all measured using a system NaI (Tl) 3″ × 3″. The results that the radioactive effectiveness of uranium for all samples are ranged 17.19 to 38.68 Bq/Kg and at a rate of 30.55 Bq/Kg for all samples. Thorium series values were between 56.45 to 13.26 Bq/Kg with average 38.60 Bq/Kg. With regard to potassium, values were ranged 537.20 to 118.30 Bq/Kg at a rate of 250.25 Bq/Kg. The values of radioactive effectiveness for potassium are within the globally allowed compared with the radioactive effectiveness of the Thorium. The radium equivalent and the rate absorbed dose in air and the external and internal hazard index and the annual effective dose has been calculated and that all values are within the globally allowed limits.

Fertility Cancer and Hereditary Risks in Soil Sample of Nasarawa, Nasarawa State, Nigeria

A survey of Fertility Cancer and Hereditary Risks in Soil Sample of Nasarawa was carried out. This study assessed the level of Fertility Cancer and Hereditary Risks in some part of Nasarawa using the gamma-ray spectrometry. The mean concentration for 40K was 645.29 ± 07.32 Bq/kg, for 226Ra was 28.43 ± 4.8422 Bq/Kg and for 232Th was 66.84 ± 2.0201 Bq/Kg. The average effective dose due to the ingestion was 0.36±0.1µSv/y which was approximately 1000 times lower than the world average effective dose. Radium equivalent activity Raeq (Bq/kg), alpha index and total cancer risk were found to be 161.44±8.08 Bq/kg, 0.142±0.02 and (0.21±0.05) ×10-5 respectively. UNSCEAR/ USEPA stipulated that; radium equivalent activity, alpha index, effective dose and total cancer risk should not exceed the limit of 370 Bq/kg, unity, 300 µSv/y and 1 ×10-4 respectively. Hence the values obtained in this work were within the acceptable limits. This implies that the ingestion or inhalation of soil is not associated with any radiological risk of concern.

In-situ assessment of natural terrestrial-radioactivity from Uranium-238 (238U), Thorium-232 (232Th) and Potassium-40 (40K) in coastal urban-environment and its possible health implications

The risk of natural terrestrial radioactivity on human health is often underestimated, and environmental safety awareness is necessary. Hence, this study aims to assess natural sources of gamma radiation emitter in coastal urban-environment using the radiometric technique. The dosage of gamma radiation from a parent radionuclide such as Uranium-238 (238U), Thorium-232 (232Th) and Potassium-40 (40K) and were measured using portable gamma spectroscopy. The result showed that the measured value of 238U activity was between 10.81 $$\pm$$ ± 0.69 and 46.31 $$\pm$$ ± 1.43 Bqkg−1. The mean value was estimated to be 35.44 $$\pm$$ ± 0.97 Bqkg−1 which is slightly higher than the world average. Meanwhile, 232Th activity ranges from 28.42 $$\pm$$ ± 1.12 to 69.43 $$\pm$$ ± 1.76 Bqkg−1 with the calculated mean value of 92.57 $$\pm$$ ± 1.17 Bqkg−1 while 40K activity ranged between 31.30 ± 1.32 and 328.65 ± 2.32 Bqkg−1 with the estimated mean 137.59 $$\pm$$ ± 2.42 Bqkg−1. Radiological parameters such as radium equivalent (Req), internal hazard (Hint) and external hazard (Hext) assessment were in the range of 66.00 Bqkg−1 to 141.76 Bqkg−1, 0.232 to 0.452 and 0.178 to 0.383, respectively. The measured values of gamma dose-rates ranged between 54.283 ± 0.78 and 117.531 ± 1.14 nGyh−1 with the calculated mean value of 84.770 ± 0.97 nGyh−1.

Measurement of Natural Radionuclides and Radon Gas Concentration in Surface Soil samples within Jalingo Metropolis, North East Nigeria

Activity concentrations of radionuclides (226Ra, 232Th, 40K) and radon gas in soil samples collected within Jalingo Metropolis were assessed by gamma spectrometric techniques using Na (TI) scintillation detector. The result showed an average activity concentration of 226Ra, 232Th and 40K to be 18.626±7.31 Bq/kg, 16.709±10.96 Bq/kg and,167.935±389.33 Bq/kg. The concentrations of 226Ra, 232Th were lower than the world average value while 40K was far higher that the recommended value.Most people in the study area use soil for building construction therefore, it was necessary to asses if there are any radiological hazards associated with the soil. This was achieved by determining Radium equivalent activity (Raeq), internal hazard index (Hin) and Annual effective dose rate. The result indicates that the indices are within normal limit. The Radon concentration in soil varies 11.126±1.315 kBq/kg to 30.374±3.331 kBq/kg with a mean value of 17.881±7.019 kBq/kg which is within the safety limits. Generally, the result showed that the soil in the study area might not pose major hazard to the members of the public

Assessment of Natural Radioactivity in Some Soil Samples from Kutha District in Babylon Governorate, Iraq

The activity concentrations of natural radionuclides of the elements (40K, 238U and 232Th), collected from Kutha district of Babylon governorate are studied and evaluated. Twenty soil samples with (0-15) cm in depth are collected. Gamma spectrometer NaI (TI) source is used for calibration. The radioactivities of natural isotopes K-40, U-238 and Th-232, were assessed. These studies show that radio activities of isotopes are acceptable according to the standard levels. Also, the activity of radium equivalent, the rate of annual effective dose, average air volume and external risk index are evaluated. The results are found within the internationally tolerable values. The results show that the mean of the radioactivity of 238U is (19.1565)Bq / kg, while it is (54.501) Bq/kg for 232Th and (179.578) Bq/kg for 40K. The study results showed that the average of radiological effects, like the Radium equivalent (Raeq), the rate of absorbed dose (Dr), the index of external hazard (Hex), the index of internal hazard (Hin), the index of representative gamma hazard (Iγ), the Annual Effective Dose Equivalent (AEDE) and the Excess Lifetime Cancer Risk (ELCR) are as follow: 110.920 Bq/kg, 50.1838 nGy/h, 0.29953, 59.1530, 27.996, 0.34 mSv/y and 1.268x10-3, respectively. Keywords: Natural radioactivity, Absorption, External hazard, Effective annual dose, Excess lifetime cancer risk.

Activity Concentrations of Naturally Occurring Radioactive Materials And Dose Calculation of Soils And Rocks Materials From A Superphosphate Industry

Activity concentration of Naturally Occurring radioactive Materials in samples from superphosphate industry was determined using Neutron Activation Analysis and radiological parameters calculated. Mean Annual Effective-Dose Equivalent(mSv/y), External and Internal Hazard, Annual Gonad Dose Equivalent(mSv/y), Radium Equivalent (Bq/kg), Absorbed Gamma Ray Dose(nGy/h), Potential Toxic Elements, Activity Utilization, and Gamma Representation Index are 87.0, 0.4, 0.5, 517.7, 137.3, 70.9, 20101.3, 9388.9, and 1.1, respectively. Most of the sample had activity concentrations of naturally occurring radioactive materials exceeding world average, indicating that activities of the industry impact on the environment. These results are good baseline data for future follow-up on activities of company.

Assessment the Natural Radioactivity of Radionuclides ( 226Ra, 232Th, 40K, and 137Cs) in Wheat Grain

This paper investigates the activity concentration of radionuclides (226Ra, 232Th, 40K and 137Cs) in the wheat grain samples using a high-purity germanium detector. Thirty-six wheat grain samples were collected from different locations of Koya City, Iraqi Kurdistan region. Average activity concentrations of 226Ra, 232Th and 40K in wheat grain are found to be 0.407 ± 0.097 Bq.kg-1 for 226Ra, 0.36 ± 0.14 Bq.kg-1 for 232Th and 109.25± 2.214 Bq.kg-1 for 40K, respectively. The measured activity concentrations for the radionuclides are compared with the reported data from other countries. In addition, the fallout radionuclide of 137Cs has no detection of in the wheat grain samples. The radium equivalent activity Raeq, internal and external hazard indices Hin and Hex, and annual gonadal dose equivalent are calculated for the measured samples. The total ingestion dose is 113.19 µSv.y-1, which is below the world average value of 290 µSv.y-1.

Determination the Natural Radioactivity Levels at Selected Regions in Al-Najaf Governorate

The natural radioactivity levels for radium(226Ra), thorium (232Th) and potassium (40K) have been determined in soil samples selected from different regions in Najaf governorate in Iraq. The samples were collected from the ground surface. Eight samples were measured by gamma ray spectroscopy using high purity germanium detector. The levelsof radionuclides concentrations in selected samples 232Th, 226Ra and 40K were in the range of (2.5±0.29 to 7.7±0.52) Bq/kg (6.3±0.43 to 16.4±1.9) Bq/kg and (31.5±3.4 to 204.1±11.9) Bq/kg for, respectively. The mean Radium Equivalent Activity, External and Internal Hazard Indices, the Absorbed Dose Rate in Air and the Annual Effective Doses Equivalent were studied and found these parameter are less than the reported values. Therefore, the radioactivity in the studied area in Najaf does not pose any radiological hazard to the general public.