scholarly journals Radioactive nuclides in phosphogypsum from the lowveld region of South Africa

2016 ◽  
Vol Volume 112 (Number 1/2) ◽  
Author(s):  
Xolani Msila ◽  
Frans Labuschagne ◽  
Werner Barnard ◽  
David G. Billing ◽  
◽  
...  

Abstract We evaluated the suitability of phosphogypsum from the Lowveld region of South Africa (LSA), for the manufacturing of building materials, with reference to (1) the National Nuclear Regulator Act 47 of 1999 and (2) the radioactivity associated risks as quantified in terms of the external and internal hazard indices, the activity concentration index and the radium equivalent. The distribution of radioactive nuclides in the LSA phosphogypsum was also examined. Analyses of 19 samples of the phosphogypsum show that phosphogypsum contains lower activity concentrations of naturally occurring radioactive nuclides of uranium and thorium and their progeny than the 500 Bg/kg limit set for regulation in South Africa. The potassium-40 (40K) activity concentration was below the minimum detectable amount of 100 Bq/kg. The values obtained for external and internal hazard indices and the activity concentration index were: 2.12 0.59, 3.44 0.64 and 2.65 0.76 respectively. The calculated radium equivalent Raeq was 513 76Bq/kg. The final decision regarding phosphogypsum’s suitability for use as a building material should consider scenarios of use.

2019 ◽  
Vol 13 (27) ◽  
pp. 164-173
Author(s):  
Zainab Mohammed Hassan

In this work, measurements of activity concentration of naturally occurring radioactive materials (NORM) isotopes and their related hazard indices for several materials such as crude oil, sludge and water in Ahdeb oil fields in Waste governorate using high pure germanium coaxial detection technique. The average values for crude oil samples were174.72Bq/l, 43.46Bq/l, 355.07Bq/l, 264.21Bq/l, 122.52nGy/h, 0.7138, 1.1861, 0.601 mSv/y, 0.1503mSv/y and 1.8361 for Ra-226, Ac-228, K-40, Ra eq, D, H-external and H-internal respectively. According to the results; the ratio between 238U to 232Th was 4, which represents the natural ratio in the crust earth; therefore, one can be strongly suggested that the geo-stricture of the Ahdeb oil fields dose not contents any kind of rocks. Although the results indicate the rising in the activity concentration of NORM isotopes, the national and international comparisons proved that it is still in the world range limits.


2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
W. R. Alharbi ◽  
A. El-Taher

Due to increased global demand for clay, the present work involves the use of INAA for elemental analysis and pollutants concentration in clay. The samples were collected from Aswan in South Egypt. The samples were irradiated using the thermal neutrons “at the TRIGA Mainz research reactor” and at a neutron flux “of 7 × 10 n/cm s”. Twenty-six elements quantitatively and qualitatively were specified for the first time upon studying the samples. The elements determined are U, Th, Ta, Hf, Lu, Eu, Ce, Ba, Sn, Nb, Rb, Zn, Co, Fe, Cr, Sc, Sm, La, Yb, As, Ga, K, Mn, Na, Ti, and Mg. The concentrations of natural radionuclides232Th,226Ra, and40K were also calculated. Based on these concentrations, to estimate the exposure risk for using clay as raw materials in building materials, the radiation hazard indices such as radium equivalent activities, effective doses rate, and the external hazard indices have been computed. The obtained results were compared with analogous studies carried out in other countries and with the UNSCEAR reports.


2016 ◽  
Vol 26 (3) ◽  
pp. 317-326 ◽  
Author(s):  
Nabil M. Hassan ◽  
N. A. Mansour ◽  
M. Fayez-Hassan ◽  
Samar Fares

The concentrations of 238 U (226Ra), 232Th, and 40K for the commonly used decorative building materials (15 marble and 15 ceramic) in Egypt were measured using gamma spectroscopy system. Radionuclides concentrations in marble samples were ranged from: ND to 49.92 ± 7.74 Bq kg−1 for 226Ra, 8.30 ± 1.70 to 119.52 ± 16.00 Bq kg−1 for 232Th, and 32.60 ± 4.25 to 2238.33 ± 242.66 Bq kg−1 for 40K while in ceramic samples the concentration ranged from: 28.42 ± 5.41 to 118.70 ± 20.34 Bq kg−1 for 226Ra, 30.65 ± 5.49 to 114.15 ± 18.78 Bq kg−1 for 232Th, and 389.54 ± 49.57 to 1069.83 ± 124.50 Bq kg−1 for 40K, respectively. These results imply that radium and thorium concentrations were below the worldwide recommended values but potassium was above the standard guideline. Radiological hazards indices of radium equivalent activity (Raeq), external and internal hazard indices: Hex and Hin, respectively, and annual effective doses of the investigated materials due to the presence of those radionuclides were calculated and had values less than the worldwide recommended values of 370 Bq kg−1, unity and 1 mSv y−1, respectively. Therefore, the studied types of marble and ceramic can be safely used as decorative building materials.


2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Willis Otieno Gor Odongo ◽  
Margaret Chege ◽  
Nadir Hashim ◽  
Shinji Tokonami ◽  
Kranrod Chutima ◽  
...  

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.


2016 ◽  
Vol 79 (12) ◽  
pp. 2174-2178
Author(s):  
ALI ABID ABOJASSIM ◽  
DAHIR MOHAMMAD DAHIR ◽  
AZHAR S. ALABOODI ◽  
ABBAS H. ABONASRIA

ABSTRACT This work studies the activity concentration of natural radioactivity in 20 different types of rice, including imported rice and that produced locally. The rice samples were collected from markets and farms in Iraq, and then a natural radioactivity investigation was done in the environmental laboratory of the Kufa University, using gamma-ray spectrometer systems. The research focused on measuring the activity concentration of natural radioactivity (238U, 232Th, and 40K) to determine the level of the radium equivalent activity, internal hazard indices, and annual effective dose. The results show that all these parameters are within the permissible limits and that radioactivity is present in almost all foodstuffs at levels ranging from 40 to 600 Bq/kg of food. Radioactivity in foodstuffs is attributed to a natural source, potassium-40, and to artificial sources, which include industrial radioactivity, weapons testing, and accidents involving radioactivity. In this article, radionuclides have been identified for most of the common species of rice available in Iraqi markets; in addition, radium equivalent activity, internal hazard indices, and annual effective dose were calculated and compared with the permissible dose to estimate the risk of radioactive isotopes in the rice crop.


2019 ◽  
Vol 186 (4) ◽  
pp. 520-523 ◽  
Author(s):  
Shittu Abdullahi ◽  
Aznan Fazli Ismail ◽  
Supian Samat

Abstract The activity concentrations of 226Ra, 232Th and 40K radionuclides from common building materials used by Malaysian people for construction purposes were studied using High-Purity Germanium (HPGe) detector. The measured activity concentrations of the aforementioned radionuclides range from 10 ± 1 Bq kg−1 (limestone) to 155 ± 61 Bq kg−1 (feldspar), 12 ± 3 Bq kg−1 (limestone) to 274 ± 8 Bq kg−1 (kaolin) and 62 ± 19 Bq kg−1 (limestone) to 1114 ± 20 Bq kg−1 (pottery stone) for 226Ra, 232Th and 40K, respectively. The measured activity concentrations of the natural radionuclides reported herein were found to be in accordance with other previous studies. In general, the activity concentration of the natural radionuclides revealed that all the determined values were below the recommended limit.


2014 ◽  
Vol 29 (2) ◽  
pp. 128-134 ◽  
Author(s):  
P.K. Manigandan ◽  
Chandar Shekar

As part of monitoring the exposure of the general public to natural radioactivity, the activity concentration of naturally occurring radionuclides in soil samples in an elevated radiation background area of Western Ghats was determined using gamma-ray spectrometry. Average values of the activity concentration of radionuclides, outdoor terrestrial gamma dose rate, annual effective dose equivalent and radiation hazard indices from soil activity were estimated. The activity concentrations of 232Th and average outdoor terrestrial gamma dose rate were found to be higher than the world average, possibly affecting the Western Ghats environment in general. Therefore, radiological risks to the general population from ionizing radiation from the naturally occurring radionuclides in the soil are considered to be significant. How- ever, other radiological hazard indices were found to be within permissible limits.


Nukleonika ◽  
2019 ◽  
Vol 64 (2) ◽  
pp. 65-70
Author(s):  
Monika Śleziak ◽  
Marek Duliński

Abstract The isotope activity concentration of rocks and bottom sediments was evaluated based on the samples collected from sedimentation ponds and gangue repositories. Radium 226Ra, thorium 228Th and potassium 40K activities were measured by gamma spectrometry using high-purity germanium detector – HPGe 4020. The radiation effect resulting from the presence of natural radionuclides was estimated by radiological hazard indices such as f1 and f2 coefficients, radium equivalent, internal and external hazard indices and absorbed dose rate. Performed measurements and calculations have shown that the bottom sediments are most contaminated. They may pose a serious radiological hazard for present and future generations.


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