RADIOMETRIC SURVEY OF THE TYAA RIVER SAND MINE IN KITUI, KENYA

2020 ◽  
Vol 188 (4) ◽  
pp. 405-412 ◽  
Author(s):  
S M Matsitsi ◽  
J M Linturi ◽  
J M Kebwaro ◽  
L M Kirago

Abstract Gamma spectroscopic analyses of sand and rock samples from Tyaa River report an average activity concentration of 33 ± 1, 55 ± 2.8 and 812 ± 40.46 Bqkg−1 for 226Ra, 232Th and 40K, respectively in the sand. A similar analysis of rock samples reveals a mean of 21 ± 2.47, 49 ± 2.47 and 782 ± 39.13 Bqkg−1 for 226Ra, 232Th and 40K, respectively. The absorbed dose rate in rocks averaged 75 ± 3.78 nGyh−1, while in the sand was 86.2 ± 4.31 nGyh−1. The ranges and mean radiological hazard indices (radium equivalent, internal and external) were within the permissible limits and the use of sand and rocks from this mine as construction material pose no health risks. Correlation analysis between the radioactivity in the sand and rocks reveals weak non-linear positive relationships suggesting that they might be from different bedrocks.

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
I. Akkurt ◽  
K. Günoğlu

The natural radioactivity existed since creation of the universe due to the long life time of some radionuclides. This natural radioactivity is caused byγ-radiation originating from the uranium and thorium series and40K. In this study, the gamma radiation has been measured to determine natural radioactivity of238U,232Th, and40K in collected sedimentary rock samples in different places of Turkey. The measurements have been performed usingγ-ray spectrometer containing NaI(Tl) detector and multichannel analyser (MCA). Absorbed dose rate (D), annual effective dose (AED), radium equivalent activities (Raeq), external hazard index (Hex), and internal hazard index (Hin) associated with the natural radionuclide were calculated to assess the radiation hazard of the natural radioactivity in the sedimentary rock samples. The average values of absorbed dose rate in air (D), annual effective dose (AED), radium equivalent activity (Raeq), external hazard index (Hex), and internal hazard index (Hin) were calculated and these were 45.425 nGy/h, 0.056 mSv/y, 99.014 Bq/kg, 0.267, and 0.361, respectively.


2020 ◽  
Vol 189 (2) ◽  
pp. 234-241 ◽  
Author(s):  
Jahan Zeb ◽  
Mohammad Wasim ◽  
Sardar A Shah ◽  
Safia Khanam ◽  
Hajira Tahir ◽  
...  

Abstract Chemical phase and distribution of natural radionuclides (226Ra, 232Th and 40K) were determined for sand samples collected from ten different beaches of Karachi. All samples, except one, were identified with major and minor phases as SiO2 and CaCO3, respectively. The average activity concentrations were 24.9, 25.0 and 239 Bq kg−1 for 226Ra, 232Th and 40K, respectively. Including all samples, the average radium equivalent activity was 79.1 Bq kg−1. The external and internal radiation hazard indices and representative level index were all found below unity. The average air absorbed dose rate at 1 m above the sand due to the natural radionuclides was 18.3 nGy h−1, which was less than the world average for soil. The corresponding annual effective dose rate was 22.4 μSv y−1. It was found that Raeq had positive significant correlation with the amount of quartz present at the beaches.


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.


2012 ◽  
Vol 27 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Nevenka Antovic ◽  
Danilo Boskovic ◽  
Nikola Svrkota ◽  
Ivanka Antovic

Soil samples from Mojkovac, Montenegro, were analyzed by standard gamma-spectrometry for radioactivity due to 226Ra, 232Th, 40K, and 137Cs. Average activity concentrations have been found to be 28.6, 43.1, 620.8, and 55 Bq/kg, respectively. In order to evaluate the radiation hazard, radium equivalent activity, absorbed dose rate, annual effective dose, external and internal hazard indexes, and the annual gonadal dose equivalent were determined and found to be at an average of 133.79 Bq/kg, 65.18 nGy/h, 79.93 mSv/y, 0.37, 0.45, and 0.46 mSv/y, respectively. With life expectancy taken to be 70 years, a mean lifetime outdoor gamma radiation was calculated as 5.6 mSv, yielding a lifetime cancer risk of 2.8?10-4.


Clay Minerals ◽  
2015 ◽  
Vol 50 (2) ◽  
pp. 221-232 ◽  
Author(s):  
Muazzez Çelik Karakaya ◽  
Mahmut Doğru ◽  
Necati Karakaya ◽  
Hasibe Cingilli Vural ◽  
Fatih Kuluöztürk ◽  
...  

AbstractThe activity concentrations of natural radionuclides in peloids were studied to assess the radiologic hazard from 18 Turkish spas. The peloids are mainly used for therapeutic treatments, rheumatic diseases and aesthetic purposes. The concentrations of the natural radionuclides 226Ra, 232Th, 40K and 137Cs were determined with a gamma ray spectrometer using a HPGe detector. The average activity concentrations of 226Ra, 232Th, 40K, and 137Cs in the peloids studied were 110.69, 71.52, 576.48 and 0.447 Bq/kg, respectively. The radium equivalent activities in the peloid samples ranged from 63.3 to 766.77 Bq/kg. The absorbed dose rate (Dout) varied between 37.52 and 330.67 nGy/h and most of the observed spa doses are greater than the worldwide recommended values. The annual effective dose values range from 0.26 to 2.78 μSv/y. The annual gonadal dose equivalents of the samples vary from 224.07 to 2283.55 with a mean of 821.99 μSv/y.


2019 ◽  
Vol 188 (1) ◽  
pp. 98-108
Author(s):  
F O Wanjala ◽  
N O Hashim ◽  
D Otwoma ◽  
C Nyambura ◽  
J Kebwaro ◽  
...  

Abstract The activity concentration of radionuclides 238U, 232Th and 40K in soil and the absorbed dose rate (ADRA) at 1 m above the ground in Ortum was determined. The activity concentration in soils ranged from 33 to 85, 20 to 67 and 148–1019 Bq kg–1, respectively with an average of 40 ± 1.43, 56 ± 1.46 and 425 ± 19.24 Bq kg–1, respectively. The activity concentration of 232Th and 238U was found to reduce with increasing depth while that of 40K increased with increasing depth. The average activity concentration in soil was higher than the world average values. The average ADRA in air at 1 m above the ground was found to be 112 ± 29.6 nGy h–1. The soil and rocks in Ortum are recommended for use because the activity concentration of the terrestrial radionuclides is lower than the recommended threshold values.


2020 ◽  
Vol 188 (3) ◽  
pp. 316-321
Author(s):  
Fei Tuo ◽  
Xuan Peng ◽  
Qiang Zhou ◽  
Jing Zhang

Abstract Radioactivity of 226Ra, 232Th, and 40K were measured in a total of 92 samples, including eight commonly used types of building materials that were obtained from local manufacturers and suppliers in Beijing. Concentrations were determined using high-purity germanium gamma-ray spectrometry. The 226Ra, 232Th, and 40K activity concentrations in all samples varied from 10.1 to 661, 3.3 to 555 and 3.2 to 2945 Bq per kg with an average of 127.8, 114.8, and 701.5 Bq per kg, respectively. The potential radiological hazards were estimated by calculating the absorbed dose rate (D), radium equivalent activity (Raeq), external hazard (Hex), and internal hazard (Hin) indices. The investigated building materials were classified into different types according to the radioactivity levels. Results from this research will provide a reference for the acquisition, sales, and use of building materials. Attention should be paid to the use of coal cinder brick, ceramic, and granite in the construction of dwellings.


2020 ◽  
Vol 13 (1) ◽  
pp. 73-77

A total of 10 cement samples were collected from the manufactures and markets. Spectrometry analysis of Sodium Iodide NaI (Tl) detector was used for measuring the samples' specific activity. The obtained specific activities of (226Ra, 232Th and40 K) were (35, 30 and 400) Bq/kg, respectively, which are below the critical values suggested by UNSCEAR2000. The radiological hazard indices of radium equivalent activities (Raeq), the indoor absorbed dose , the internal annual effective dose equivalent (Ein) and the internal index (Hin) were calculated. All of the obtained values were below the world wide recommendation values. Fortunately, from the analyzed results, it was concluded that the local and imported cements in Erbil governorate will make no risk when used in building constructions.


1970 ◽  
Vol 33 (1) ◽  
pp. 117-130 ◽  
Author(s):  
KA Kabir ◽  
SMA Islam ◽  
MM Rahman

This paper presents the first reports on the natural and anthropogenic radionuclides in soil and sediment of Jessore, a south-western district of Bangladesh. Surface soil and freshwater sediment were collected from in and around some major water-bodies of this district. To assess the radiological hazard of the natural radioactivity, the radium equivalent activity, the absorbed dose rate, and the external and internal hazard indices were calculated. In the soil and sediment in general, the activity concentration of 232Th was found to be higher than that of  226Ra, while that of 40K markedly exceeds the values of both 226Ra and 232Th. The average activities of 226Ra and 232Th in this area were found to be higher than the world average. There was no activity due to fallout (137Cs) in this area. The radium equivalent activity and the absorbed dose rate due to the natural radionuclides were found to be respectively lower and higher than the world average. The external and internal hazard indices were found to be well below the hazard limit of unity. Our results compare fairly well with other published results.  Key words: Soil, Sediment, Natural lake, Radioactivity, Dose rate DOI: 10.3329/jbas.v33i1.2956 Journal of Bangladesh Academy of Sciences, Vol. 33, No. 1, 117-130, 2009


Author(s):  
P.M. Gyuk ◽  
J.O. Anaegbu ◽  
H.O. Aboh ◽  
R. Daniel ◽  
A. Aruwa ◽  
...  

The background radiation of the areas was collected at random for each point using a rados survey meter. The detectors (two rados survey meter were used) were placed 1 meter above the ground with the operator positioned a few meters away. Three (3) readings were taking from each detector in other to reduce error or reach accuracy in obtaining the background readings from each randomly selected point where soil samples were later collected. In the current study, the concentration levels of naturally occurring radioactive materials (NORMs) of 40K, 232Th, and 238U in the surface soil samples of selected areas in kigo road new extension Kaduna north, Kaduna in Nigeria were studied. The collected soil samples were analyzed by means of gamma-ray spectrometry. The mean activity concentrations of the natural occurring radionuclides of  226Ra, 232Th and 40K in the soil samples were estimated to be 62, 78.35, 227.17 Bq/kg respectively for kigo road new extension respectively. Radium equivalent activity, absorbed dose rate, annual effective dose equivalent were also calculated for assessment of radiological risk. External hazard value (Hex) is between 0.3163 and 0.9557 and Internal hazard value is between 0.4462 and 1.1618. The worldwide average activity concentrations of 226Ra, 232Th and 40K in soil samples from various studies around the world have values of 37, 30 and 400 Bq/kg respectively [UNSCEAR, 2000]. The values compared well with published data from UNSCEAR shows Ra-226, Th-232 from the location are well above the standards while K-40 below the risk value.


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