Distributions and Risk Assessment of the Natural Radionuclides in the Soil of Shoubra El Kheima, South Nile Delta, Egypt

Due to heightening concern about radiation hazards protection, activity concentrations of 226Ra, 232Th, 40K in forty soil samples collected from Shoubra El Kheima in the South Nile Delta were measured using gamma-ray spectrometry. The mean activity concentrations of 226Ra and 40K were higher in 20% of the considered samples than the world average values. A comprehensive comparison with up-to-date data was carried out. Spatial distribution maps of the measured radionuclides and radiological parameters were generated. The distributions of natural radionuclides were influenced by the soil organic matter, clay content, and scavenger metals oxides, as well as differences in the physical and chemical attributes and solubility of these radionuclides. The results revealed that industrial activity and agricultural practices in the study area caused an incremental increase in 226Ra and 40K activity concentrations. It can be deduced that although there are intensive industrial activities in this area, the natural radiation that comes from the soil is normal and does not pose a significant radiological hazard to the public. The natural radioactivity of soil in this area needs to be monitored periodically to prevent unnecessary radiation exposure to inhabitants.

Assessment of Activity Concentration of Radionuclides in Soil and Cassava Food Crop from Solid Mineral Mining Site in Ishiagu, Ivo L.G.A of Ebonyi State, Nigeria

The assessment of activity of concentration of radionuclides in soil and food crops from solid mineral mining sites at Ishiagu, in Ivo L.G.A of Ebonyi State was carried out using the necessary measuring instruments. Samples of soil and cassava crop collected from around the mining sites. The samples were analysed using gamma ray spectrometry. The average activity concentration of 226Ra, 232Th and 40K in soil samples were 12.37,16.08, and 144.29 Bqkg-1 while those for cassava were 2.81, 16.80, and 205.41 Bqkg-1. The soil/plant radionuclide transfer ratio estimated are 0.62, 2.43 and 2.51 for 226Ra, 232Th and 40K, respectively. All the radiological risk parameters estimated are relatively low. The result of this work showed that the obtained results for all samples were lower than the international accepted limit. Hence, from radiological health standpoint, the obtained values of effective doses may not pose significant threat to both human and the environment.

Assessment of contamination of natural and anthropogenic radionuclides in rice samples collected from Songkhla province, Thailand

Study on assessment of contamination of natural and artificial radionuclides in agricultural products samples are very important to all human being as a consumer. In the present study, we have measured and evaluated the specific activities of natural (40K, 226Ra and 232Th) and anthropogenic (137Cs) radionuclide in rice samples. The 30 rice samples were collected from general and department stores at Songkhla province in the south of Thailand. The high-purity germanium (HPGe) detector and gamma-ray spectrometry analysis system which was set-up in advanced laboratory in Thailand Institute of Nuclear Technology (public Organization) or TINT were employed to perform all of measurements and analysis for this study. The frequency distribution of specific activities of 40K, 226Ra, 232Th and 137Cs for this study were also studied and found to be asymmetrical distribution with the skewness of 1.29, 1.43, 2.32 and 0.82, respectively. For this reason, the median values of specific activities of 40K, 226Ra and 232Th which were 620.04 ± 44.30, 3.73 ±0.54 and 2.44 ±0.54 Bq/kg respectively, should be selected and also used to calculate some related radiological hazard indices in this study. Furthermore, the excess lifetime cancer risk (ELCR) would be also evaluated and presented. Moreover, the results of present study were taken to compare with some data and studies in Thailand and global measurement and calculations. It was found that the outcomes satisfied the standards of UNSCEAR and IAEA.

Radiological hazard assessments of radionuclides in building materials, soils and sands from the Gaza Strip and the north of Sinai Peninsula

Radiological hazards to the residents of the Gaza Strip, Palestine and the north of the Sinai Peninsula, Egypt, were determined using the naturally occurring radionuclides (226Ra, 232Th and 40K) in 69 samples of building materials (demolition debris, plasters, concretes, from recycling plants and raw cements from suppliers), soils and sands collected in the field. The radiological hazard indices and dose rates calculated with the activity concentrations of radionuclides in those materials determined by gamma-ray spectrometry indicate that the values are all within the global limits recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation 2000 and European Commission 1999. The results of Spearman's correlation and hierarchical cluster analysis for 210Pb in the building materials, soils and sands suggest that the samples include 210Pb from the atmospheric fallout. The medium correlation between 232Th and 40K in demolition debris implies that their activity concentrations are characteristic of the building materials and constituents of the demolition debris. Non-natural ratio of 238U/235U was found in the soil and sand samples collected in the Gaza Strip. Furthermore, 137Cs and 241Am were detected in some soil, sand and demolition debris samples analyzed in this study. The origins of those anthropogenic radionuclides were considered.

Radiological Hazard Evaluation of Some Egyptian Magmatic Rocks Used as Ornamental Stone: Petrography and Natural Radioactivity

Magmatic rocks represent one of the most significant rocks due to their abundance, durability and appearance; they can be used as ornamental stones in the construction of dwellings. The current study is concerned with the detailed petrography and natural radioactivity of seven magmatic rocks. All are commercial granitic rocks and are identified as black Aswan, Nero Aswan, white Halayeb, Karnak, Verdi, red Hurghada and red Aswan. Their respective mineralogical compositions are classified as porpheritic granodiorite, granodiorite, tonalite, monzogranite, syenogranite, monzogranite and syenogranite. A total of nineteen samples were prepared from these seven rock types in order to assess their suitability as ornamental stones. Concentrations of 226Ra, 232Th and 40K radionuclides were measured using NaI (Tl) scintillation gamma-ray spectrometry. Among the studied magmatic rocks, white Halayeb had the lowest average values of 226Ra (15.7 Bq/kg), 232Th (4.71 Bq/kg) and 40K (~292 Bq/kg), all below the UNSCEAR reported average world values or recommended reference limits. In contrast, the other granitic rocks have higher values than the recommended limit. Except for the absorbed dose rate, other radiological hazard parameters including radium equivalent activity, annual effective dose equivalent, external, and internal hazard indices reflect that the White Halyeb rocks are favorable for use as ornamental stone in the construction of luxurious and high-demand residential buildings.

Исследование концентрации радионуклидов в колодцах, используемых в качестве питьевой воды в северной Нигерии. На примере мегаполиса Джос

The increasing health effects of nuclear radiation occasioned by the enhanced human activities in the environment necessitated the need for constant investigation and assessment of radiological impact on the general populace within a confined area. Based on this, Twenty two (22) (Hand dug and motorized) well water samples were collected from various locations distributed across Jos Metropolis, Jos North LGA, Plateau State, Nigeria and analyzed for the concentration activity of these radionuclides (40K, 210Pb, 224Ra, 232Th, 238U) using radiochemical analysis technique, a high resolution gamma ray Spectrometry and a radon emanometry technique. The estimated mean concentration activity of 40K, 210Pb, 224Ra, 232Th and 238U in well water samples use as drinking water were determined. The mean concentration ranges from 1.36±0.51 Bq/l to 5.75±1.30 Bq/l. The mean concentration of 40K in well water samples ranges from 3.80±1.19 Bq/l to 2.05±0.30 Bq/l. The mean concentration of dissolved 224Ra in well water samples collected varies from 5.75±1.30 Bq/l to 1.95±0.58 Bq/l. 210Pb has an average concentration of 2.68 ± 0.80 Bq/l to 1.97±0.87 Bq/l. 232Th and 238U had average concentrations of 3.09 ± 0.57 Bq/l to 1.89±0.24 Bq/l and 5.41 ± 1.37 Bq/l to 1.36±0.51 Bq/l respectively. 210Pb and 224Ra were slightly above the recommended limits of 0.10 Bq/l and 1.00 Bq/l respectively, this can be attributed to the geological formation of the sampled area. 232Th and 238U where within the accepted standard limits of 1.00 Bq/l and 10.00 Bq/l recommended value by WHO (World Health Organization) and ICRP (International commission on radiological protection). Activity concentrations of measured radionuclides are in general decreasing in this order: 238U > 40K > 224Ra > 232Th > 210Pb for well water samples within Jos North LGA, respectively. Растущее воздействие ядерной радиации на здоровье, вызванное усилением деятельности человека в окружающей среде, обусловило необходимость постоянного исследования и оценки радиологического воздействия на население в пределах ограниченной территории. Было отобрано двадцать два образца колодезной воды из различных мест, распределенных по мегаполису Джос, Нигерия, и проанализированы на активность радионуклидов (40K, 210Pb, 224Ra, 232Th, 238U) с использованием метода радиохимического анализа, гамма-спектрометрии высокого разрешения и метода радоновой эманометрии. Определены средние концентрации радионуклидов в образцах воды из скважин, используемых в качестве питьевой воды. Средняя концентрация 40K колеблется от 3,80±1,19 Бк/л до 2,05±0,30 Бк/л. Средняя концентрация 224Ra варьируется от 5,75±1,30 Бк/л до 1,95±0,58 Бк/л. 210Pb от 2,68±0,80 Бк/л до 1,97±0,87 Бк/л. 232Th и 238U имели средние концентрации от 3,09±0,57 Бк/л до 1,89±0,24 Бк/л и от 5,41±1,37 Бк/л до 1,36±0,51 Бк/л. 210Pb и 224Ra были немного выше рекомендуемых пределов 0,10 Бк/л и 1,00 Бк/л, это может быть связано с геологическим строением отобранной области. 232Th и 238U находились в пределах принятых стандартных пределов 1,00 Бк/л и 10,00 Бк/л, рекомендованных ВОЗ и МКРЗ.

Natural Radionuclide Concentrations and Associated Doses Around Three Dumpsites in Lagos, Nigeria

Monitoring of environmental radiation helps to ascertain healthy vicinity which is a catalyst to the economic development of the area. Activity concentration of naturally occurring radionuclides in three (3) dumpsites in Lagos State, Olusosun Landfill, Ojota, Ilupeju dumpsite and, Gbagada dumpsite Lagos state, Nigeria were investigated using gamma-ray spectroscopy to obtain the level of radioactive exposure hazards experienced by people living in these vicinities. A total of thirty soil samples were randomly collected into a polythene bag. They were oven-dried at 110°C, pulverized, and sieved. Quantities of the samples (400 g) were sealed in cylindrical sample holders and kept for about 28 days to attain secular equilibrium between 226Ra and its decay products before analysis using gamma-ray spectrometry. The mean activity concentration obtained for 40K, 238U, and 234Th at, Ilupeju, Gbagada, and Ojota were 339.23±33.66, 11.83±19.174, 11.95±22.752 Bq/kg, 337.56 ± 36.22, 11.49±22.14, 11.54 ± 19.33 Bq/kg and 334.87±32.44, 11.42±22.39, 11.56±18.52 Bq/kg respectively. The mean absorbed dose nGy/h, annual effective dose mSv/y were calculated and their results were found to be below the global values. The results indicate that the radiation level within the dumpsites poses no significant health risk to the people living close to the dumpsites.

Photoneutron activation analysis and multivariate geostatistical approach to assess the spatial occurrence of trace heavy metals in Crisuri Basin

The Crisuri Basin, with its total length of 1093 km (among which 670 km in Romania), is subjected to an effective environmental monitoring system consisting of 18 water stations network. Their integrated information is used for the water assessment problem to understand the biogeochemical processes leading to significant pollution levels in some running water sectors. The goal of this research is to predict the most important factors causing the change of the geochemical measured parameters of some components of the Crisuri water resources. In the present paper, we developed a multivariate statistical model to estimate the spatiotemporal distribution of heavy metals in the field and to identify the contamination sources of Basin River waters. Two methods were deployed as an overall approach to fulfill the proposed objectives, namely the photoneutron activation analysis followed by high-resolution gamma-ray spectrometry and the multivariate statistical analysis. The elements analyzed by different analytical techniques and introduced in databases were As, Cd, Ca, Cu, Fe, Mg, Hg, Na, Ni, Pb, Zn, N-NH4, N-NO2, N-NO3, P-PO4, fixed residues, S-SO4, Cl, phenols and, additional oil compounds. By combining the spatially distributed geochemical data on trace heavy metals with the spatially distributed geophysical data, we obtained the most significant fingerprint factors and their associated uncertainty information concerning the water quality.