scholarly journals Estimation of Terrestrial gamma radiation (TGR) dose rate in characteristic geological formations of Jos Plateau, Nigeria

2017 ◽  
Vol 13 (4) ◽  
pp. 593-597
Author(s):  
Habu Tela Abba ◽  
Wan Muhammad Saridan Wan Hassan ◽  
Muneer Aziz Saleh ◽  
Abubakar Sadiq Aliyu ◽  
Ahmad Termizi Ramli
Keyword(s):  
Gamma Radiation ◽  
Dose Rate ◽  
Natural Radionuclides ◽  
Ground Surface ◽  
Mean Value ◽  
Gamma Ray Spectrometry ◽  
Jos Plateau ◽  
Dose Rates ◽  
Geological Formation ◽  
Geological Formations

A study was conducted to estimate the terrestrial gamma radiation (TGR) dose rates associated with the natural radionuclides 238U, 232Th and 40K in the characteristic geological formations of Jos Plateau. A total of 51 surface soils from all the geological units were collected and measured using high-resolution gamma ray spectrometry system. From the measured activity concentrations of 238U, 232Th and 40K, TGR dose rates in air outdoors 1 m above ground surface, were estimated to be in the range of 36 nGy h-1 to 456 nGy h-1, depending on the geological formation, with an overall mean value of 143 nGy h-1. The estimated mean value is by a factor of two higher than the world average value of 59 nGy h-1. Geological formation G8 (Younger granites) appear to have the highest mean TGR dose rate while G7 (sandstone, clay and shale) show the lowest mean TGR dose rate. The results of this study inferred that, TGR dose rates outdoors for Jos Plateau differs with the different geological formations and significantly contributed by 232Th. An isodose map for the distribution of TGR and exposure rate to the public due to natural sources was also plotted using ArcGIS software. The data here presented can be used to evaluate public radiation dose and to produce radiological map for the country.

scholarly journals CHANGES OF IONIZING RADIATION CAUSED BY NATURAL RADIONUCLIDES IN THE CURONIAN SPIT

2005 ◽  
Vol 13 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Milda Pečiuliene ◽  
Dainius Jasaitis ◽  
Gražina Grigaliūnaite-Vonsevičiene ◽  
Aloyzas Girgždys
Keyword(s):  
Ionizing Radiation ◽  
Gamma Radiation ◽  
Dose Rate ◽  
Natural Radionuclides ◽  
Ground Surface ◽  
Equivalent Dose ◽  
Curonian Spit ◽  
Equivalent Dose Rate ◽  
Dose Rates ◽  
Numerous Data

Taking into consideration a unique scenery of the Curonian Spit, dosimetric investigation of ionizing radiation caused by natural radionuclides is performed there. The influence of natural radionuclides present in the ground on the equivalent dose rate of gamma radiation in the ground surface air is established. Measurements of equivalent dose rate are carried out in the whole territory of the Curonian Spit in Lithuania. Especially numerous data have been collected on the coasts of the sea and bay, near them, in seaside dunes and by roads. The established equivalent dose rate values vary from 22 nSv/h (on the dune top) to 90 nSv/h (above an asphalt path). The values of the main gamma radiation source (40K and 226Ra) concentration are measured, and positive correlation of concentrations and equivalent dose rates in the ground surface air between 40K and 226Ra is determinated. It is established that 40K has the biggest influence on equivalent dose rate. The equivalent dose rate values in the ground surface air in the Curonian Spit are comparatively low (they can even be 1630 times lower in comparison to Guarapari beach, Brazil).

In situ measurement of terrestrial gamma dose rates in eastern region of Peninsular Malaysia and its relation to geological formation and soil types

2019 ◽  
Vol 107 (6) ◽  
pp. 503-516 ◽  
Author(s):  
Muneer Aziz Saleh ◽  
Ahmad Termizi Ramli ◽  
Khaidzir Bin Hamzah ◽  
Jasman Zainal ◽  
Mohsin Mohd Sies ◽  
...  
Keyword(s):  
Effective Dose ◽  
Mean Value ◽  
Peninsular Malaysia ◽  
Gamma Dose ◽  
Soil Types ◽  
Eastern Region ◽  
Dose Rates ◽  
Gamma Dose Rates ◽  
Geological Formation ◽  
Geological Formations

Abstract This present study aims to obtain baseline data of environmental terrestrial radiation and to assess the corresponding health risk in the ambient environment in eastern region of Peninsular Malaysia. The measurements were taken 1 m above the soil surface using NaI [Ti] detector with a total of 2144 measured points which covered all geological formations and soil types. The measured gamma dose rates ranged from 26 nGy h−1 to 750 nGy h−1 with a mean value of 172±90 nGy h−1. The mean gamma dose rate is three times higher than world averages of 57 nGy h−1. The data of gamma dose rates show the reading of the gamma dose rates not fit to the normal distribution. The variations of gamma dose rates based on geological formation and soil types were investigated using the unbalanced one way ANOVA. The results indicated strong significant differences due to the different geological formations and soil types. The T-test of gamma dose rates for each pair of soil types or geological formations and their hypothesis test at 95 % confidential level were compared to shows the significant difference between each pairs. The results indicate that the gamma dose rates for all pairs of soil types were significant differed except the miscellaneous soil while the gamma dose rates of the pairs of geological formation were also significant differed except the intermediate and intrusive geological formations. Acid intrusive and intermediate intrusive geological formations has the highest mean values of 223 nGy h−1 and 278 nGy h−1, respectively. These values are approximately four and five times the world average. Soil type (Steep land) has the highest gamma dose rate with the mean value of 215 nGy h−1. The radiological health information which are the total annual effective dose equivalent, the collective effective dose, lifetime effective dose and the lifetime cancer risk for each person are 0.844 mSv, 3.53×103 man Sv y−1, 59.10 mSv and 3.25×10−3, respectively. The results in eastern region of Peninsular Malaysia were comparable to different areas in Malaysia, which indicate the value reported in UNSCEAR, 2000 should be adjusted to the current status in Malaysia.

scholarly journals Real-Time Environmental Gamma Dose Rates Measurement and Evaluation of Annual Effective Dose to population of Shahbag Thana, Dhaka, Bangladesh

2018 ◽  
Vol 6 (04) ◽  
Author(s):  
Shamsad Tazmin ◽  
Dr. Mohammad Sohelur Rahman ◽  
Selina Yeasmin ◽  
Dr. M. Habibul Ahsan ◽  
Md. Mahfuzzaman
Keyword(s):  
Gamma Radiation ◽  
Effective Dose ◽  
Dose Rate ◽  
Annual Effective Dose ◽  
Natural Radionuclides ◽  
Outdoor Environment ◽  
Acquisition Time ◽  
Population Exposure ◽  
Monitoring Point ◽  
Dose Rates

Background: In this study, environmental gamma radiation dose rates were measured in the area of Shahbag Thana under Dhaka city, Bangladesh. Aim of the study: This kind of study is required to detect the presence of natural and artificial radionuclides (if any) releasing from nuclear facilities in the country or from neighbouring countries. Materials and Method: The measurement was performed using a digital portable Gamma-Scout detector. The digital portable Gamma-Scout detector was placed at 1 meter above the ground on tripod and data acquisition time for each monitoring point (MP) was 1 hour. Total 27 MPs were selected for collection of gamma-ray dose rate in the outdoor environment of Shahbag Thana. The measurements were performed during light day from January to September 2017. The MPs were marked-out using Global Positioning System (GPS) navigation. The GP Sreading of the sampling locations were varied from E: 90˚23'32.94" to E: 90˚24'31.32" and from N:23˚44'19.38" to N: 23˚43'24.3". Results: The measured dose rates due to natural radionuclides were ranged from 0.085 ± 0.0245µSv.h-1 to 0.190526 ± 0.081886 µSv.h-1 with an average of 0.145265 ± 0.025192 µSv.h-1.The annual effective dose to the population from outdoor environmental gamma radiation was varied from0.104244 ± 0.030041 mSv  to 0.233661085 ± 0.100425 mSv. The range of dose rate and annual effective dosedue to outdoor environmental gamma radiation is lower than some countries like India, Sweden, China, CzechRepublic, Italy and higher than Canada, Turkey, Indonesia, Belgium, Albania, New Zealand and some other counties. Conclusion: From this study, it was observed that there is no burden of population exposure due to man-made sources. Therefore, it can be concluded that adequate safety and radiation protection of radiological facilities had been ensured which is required for minimizing of unnecessary exposure to populations from man-made sources. The estimated mean annual effective dose found in this study is not expected to contribute significant additional hazard from the radiological health point of view.

scholarly journals Spatial distribution of gamma radiation dose rates from natural radionuclides and its radiological hazards in sediments along river Iju, Ogun state Nigeria

MethodsX ◽  
2020 ◽  
Vol 7 ◽  
pp. 101086
Author(s):  
Omeje Maxwell ◽  
Adewoyin Olusegun O. ◽  
Joel Emmanuel S. ◽  
Ikechukwu Ijeh B. ◽  
Omeje Uchechukwu A. ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Radiation Dose ◽  
Gamma Radiation ◽  
Natural Radionuclides ◽  
Dose Rates ◽  
Ogun State ◽  
Radiological Hazards ◽  
Gamma Radiation Dose

scholarly journals Activity of natural radionuclides and their contribution to the absorbed dose in the fish cubera snapper (lutjanus cyanopterus, cuvier, 1828) on the coast of Ceara, Brazil

2010 ◽  
Vol 58 (spe4) ◽  
pp. 25-32 ◽  
Author(s):  
Wagner de S. Pereira ◽  
Alphonse Kelecom ◽  
Delcy de A. Py Júnior
Keyword(s):  
Dose Rate ◽  
Standard Dose ◽  
Natural Radionuclides ◽  
Absorbed Dose ◽  
Threshold Value ◽  
Average Dose ◽  
Absorbed Dose Rate ◽  
Dose Rates ◽  
A Value ◽  
Lead 210

A methodology was developed for converting the activity concentration of radionuclides (Bq kg-1) into absorbed dose rate (Gy y-1), aiming an approach to environmental radioprotection based on the concept of standard dose limit. The model considers only the internal absorbed dose rate. This methodology was applied to the cubera snapper fish (Lutjanus cyanopterus, Cuvier, 1828) caught off the coast of Ceará. The natural radionuclides considered were uranium-238, radium-226, lead-210, thorium-232 and radium-228. The absorbed dose rates were calculated for individual radionuclides and the type of emitted radiation. The average dose rate due to these radionuclides was 5.36 µGy y-1, a value six orders of magnitude smaller than the threshold value of absorbed dose rate used in this study (3.65 10³ mGy y-1), and similar to that found in the literature for benthic fish. Ra-226 and U-238 contributed 67% and 22% of the absorbed dose rate, followed by Th-232 with 10%. Ra-228 and Pb-210, in turn, accounted for less than 1% of the absorbed dose rate. This distribution is somewhat different from that reported in the literature, where the Ra-226 accounts for 86% of the absorbed dose rate.

scholarly journals Gamma irradiation used on adult Tetranychus urticae Koch as a quarantine treatment

2014 ◽  
Vol 54 (2) ◽  
pp. 150-155 ◽  
Author(s):  
Shiva Osouli ◽  
Karim Haddad Irani Nejad ◽  
Farhoud Ziaie ◽  
Mohammad Moghaddam
Keyword(s):  
Gamma Radiation ◽  
Gamma Irradiation ◽  
Dose Rate ◽  
Tetranychus Urticae ◽  
Linear Trend ◽  
Young Females ◽  
Dose Rates ◽  
Adult Females ◽  
Tetranychus Urticae Koch ◽  
Old Females

Abstract The effect of gamma radiation with 0, 200, 250, 300, 350, 400, and 450 Gy intensities on the longevity, total number of eggs, and the percent of hatched eggs laid by irradiated females of Tetranychus urticae Koch (Tetranychidae) was evaluated. Two different groups (0–24 h old and 48–72 h old) of adult females were irradiated. The results showed that 350 and 300 Gy doses significantly reduced the longevity of the 0–24 h old females and the 48–72 h old females. The younger females were more tolerant at lower dose rates than the older females. There was a quadratic relationship between dose rates and young females, while it was linear in older females. The total number of eggs laid by females of both ages was significantly reduced with a linear trend by 250 Gy irradiation. The eggs laid by females of both the 0–24 h olds and the 48–72 h olds lost their hatchability when the dose rate was 350 Gy. It was concluded, that applying a dose rate of 320 Gy on one of the mates (male or female) before mating, or a 300 Gy on both of them, would be sufficient to cause sterility in adult mites.

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