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Soil excavation in search of mineral ores provides a means of livelihood to many families in Nigeria. However, the practice was found to be associated with many radiological health concerns that were not known to the miners and people living within the mining vicinities. In an effort to provide such useful information, the activity concentrations of 40K, 226Ra, and 232Th from tin mining areas in Zainabi, Kano, Nigeria, were analyzed using a high-purity germanium detector. The results obtained show activity concentrations of 40K, 226Ra, and 232Th higher than their corresponding world average values. A RESRAD-ONSITE software code was further used to evaluate the dose and cancer risk using a variable contamination thickness. The results obtained show an annual effective dose value greater than the maximum acceptable limit of 1 mSv/yr for non-radiation workers in Nigeria. The evaluated excess lifetime cancer risk also exceeded the United States Environmental Protection Agency threshold and the word average values of 1.45 × 10−3 and 1.06 × 10−4, respectively. Therefore, sustainable mining practices should be implemented in the areas to avert the perceived radiation-related problems. [ABSTRACT FROM AUTHOR]

Mining of mineral ore is considered one of the anthropogenic sources of elevating the activity concentrations of the natural radionuclides in the environment, which in turn causes an increased risk of human exposure via the food chain. In an attempt to evaluate the radiological burdens resulting from tin mining activities in Nigeria, farm soil and sixty-two samples of different food crops grown around tin mining areas were evaluated for the activity concentrations of 226Ra, 232Th, and 40K using a high-purity germanium detector. The mean activity concentrations of 226Ra, 232Th and 40K in soil were 64.6 ± 29.5, 72.03 ± 28.73 and 680.6 ± 324.3 Bq/kg, respectively. These values were found to be higher than their corresponding world average values. However, the mean activity concentrations of the measured radionuclides in plants were below their respective world average values, as reported by UNSCEAR. The overall average annual ingestion dose due to the consumption of the analysed plants was 151 µSv/y, which is below the reported world average value of 290 µSv/y. The results obtained show that the hazard indices were low enough to cause any immediate radiological health complications due to the ingestion of the crops grown in the studied areas. [ABSTRACT FROM AUTHOR]

Terrestrial gamma radiation is the major source of outdoor radiation exposure to human being. Because of the variation of underlying geological characteristics of surface soil, the terrestrial gamma radiation dose (TGRD) rates vary significantly with the soil type. This work performed in situ measurements of the TGRD rate for a range of geological formation and soils of Katsina State, Nigeria by using a portable hand-held radiation survey metre, RADOS. The TGRD rates ranged between 45 and 271 nGyh−1 with an overall mean value of 116 nGyh−1, which is two times higher than the world average value of 59 nGyh−1. Geological formation (Silicified sheared rock) was found to have the highest mean TGRD value of 163 nGyh−1. Likewise, soil type (lithosols, ferruginous crusts and ferruginous tropical soils) appeared to have the highest mean TGRD value of 134 nGyh−1. One-way ANOVA was used to investigate the variation of the significant difference between the geological formations and soil types with TGRD, which shows the influence of geological formation and soil types on the measured TGRD values of the study area. Measured data could further be used to evaluate the public radiation exposure and in formulating safety standards and radiological guidelines. [ABSTRACT FROM AUTHOR]

Mined Trona is a naturally occurring inorganic salt that is consumed by humans for diverse purposes in Nigeria. Due to the increase in consumption rates of these salts following a renewed government interest in solid minerals exploration and exploitation, it is imperative to assay its radiological content. Reconnaissance survey revealed that the most commonly used Trona varieties were: Farar Kanwa, Jan Kanwa, Dan Libya, Ngurnu, Manda, Farar Balma, Jar Balma and Yar Agadez. Samples of the identified Trona varieties were purchased from markets within Zaria, Nigeria. The samples were analysed using NaI (Tl) gamma ray spectrometry system. Radium equivalent activity (Raeq), annual effective dose (AED), Internal and Alpha hazard Indices (Hin and Iα) and total cancer risks (TCR) were used to assess the radiological safety of its consumption. The activity concentration of 238U (226Ra); 232Th and 40K varied widely and had an average ± error values of 42.904 ± 4.54 Bq/kg, 11.96 ± 1.41 Bq/kg and 455.28 ± 10.56 Bq/kg respectively. Raeq, AED, Iα, Hin and TCR were estimated at 95.07 ± 63.10 Bq/kg, 68.52 ± 52.53µSv/y, 0.21 ± 0.23, 0.37 ± 0.27 and (390.57 ± 299.44) × 10 − 06 respectively; which were by far less than the US EPA and UN SCEAR acceptable thresholds. It was established that the threshold consumption rate is 40 Kg/year and any value slightly higher than the threshold values will be associated with a significant radiological health risk. Therefore, at the present consumption rate of Trona in Nigeria, there is no cause for radiological concern. [ABSTRACT FROM AUTHOR]

Radiological effects due to external and internal exposure to natural radiation associated with the natural radionuclides 226Ra, 232Th, and 40K in soil of Kelantan, Malaysia was carried out. Terrestrial gamma radiation dose rates (TGRD) measurement was carried out using a portable [NaI(TI)] micro roentgen (µR) survey meter and hyper purity germanium (HPGe) detector for the activity concentrations of 226Ra, 232Th, and 40K in soil samples. The mean TGRD was found to be 209 nGy h−1 and from soil samples analyzed, the mean activity concentrations of 226Ra, 232Th, and 40K were found to be 82 Bq kg−1, 123 Bq kg−1, and 643 Bq kg−1 respectively, which were both about 3 times higher than the Malaysian average as reported by UNSCEAR 2000. The mean radium equivalent (Raeq), absorbed dose rates (D), annual effective dose (H), annual gonadal dose equivalent (AGDE) as well as external and internal radiation hazard index (Hex), which were the indicators of radiological health hazards, were found to be 307 Bq kg−1, 139 nGy h−1, 0.22 mSv y−1, 969.422 µSv y−1, 0.653 and 1.05, respectively. [ABSTRACT FROM AUTHOR]

Measurement of background radiation is of great interest for it provides useful information in monitoring environmental radioactivity. The aim of the present study is to provide information and generate database on the natural background radiation dose levels of densely populated Queen Amina Hall, Ahmadu Bello University, Zaria. The radiation dose (outdoor and indoor dose rate) were measured at 29 rooms (Block 1- 4) and their compounds using RADOS survey meter held at 1m above the ground. The measured radiation dose ranged 0.13 nGyh-1 to 0.43 nGyh-1 and 0.54 nGyh-1 to 1.72 nGyh¹ for indoor and outdoor respectively. Some of the high values recorded could be attributed due to the contribution of cosmic radiation emanating from the atmosphere as well as the geological settings of the location as there is no any artificial contributing factor within the area. The annual effective doses within the study area was found to be 0.01 mSvy-1 throughout which is quit below the world average value of 0.87 mSvy-1 for natural sources. [ABSTRACT FROM AUTHOR]

Measurements of the environmental terrestrial gamma radiation dose rate (TGRD) in each district of Kelantan state, Malaysia, were carried out using a portable hand-held radiation survey meter and global positioning system. The measurements were done based on geology and soil types of the area. The mean TGRD was found to be 209 nGy h–1. Few areas of relatively enhanced activity were observed in Pasir Mas, Tanah Merah and Jeli districts, which have a mean TGRD between 300 and 500 nGy h–1. An isodose map of the area was produced using ArcGIS software version 9.3. [ABSTRACT FROM PUBLISHER]

This study assesses the ‘radio-ecological’ impacts of Fukushima nuclear accident on non-human biota using the ERICA Tool, which adopts an internationally verified methodology. The paper estimates the impacts of the accident on terrestrial and marine biota based on the environmental data reported in literature for Japan, China, South Korea and the USA. Discernible impacts have been detected in the marine biota around Fukushima Daiichi nuclear power plant. This study confirms that the Fukushima accident had caused heavier damage to marine bionts compared with terrestrial flora and fauna, in Japan. [ABSTRACT FROM AUTHOR]

The interest in non-electric applications of nuclear energy is rising ranging from hydrogen production, district heating, seawater desalination, and various industrial applications to provide long-term answers for a variety of energy issues that both present and future generations will confront. Hydrogen is a dynamic fuel that can be used across all industrial sectors to lower carbon intensity. This study, therefore, aims at estimating the cost of nuclear hydrogen production from some light water reactors using International Atomic Energy Agency (IAEA) Hydrogen Calculator (HydCalc) program and comparing the result with similar existing studies conducted by other scholars using the Hydrogen Economic Evaluation Program (HEEP) program. The study employs six existing Light Water Reactors (LWRs) comprised of Korea Advanced Power Reactor 1400 MW electricity (APR1400), Russian VVER-1200, Davis-Besse Nuclear Power Plant in Ohio, Prairie Island NPP in Minnesota, Nine Mile Point NPP in New York, and Arizona Public Service's Palo Verde NPP to evaluate the Levelized cost of nuclear hydrogen production. Estimation of hydrogen demand was performed without carbon dioxide (CO 2) tax since nuclear power has zero CO 2 emission. The Levelized costs obtained using IAEA HydCalc and HEEP Programme were compared as follows; APR1400 cost are 2.6$/kg and 3.18$/kg, VVER1200 cost are 3.8$/kg and 3.44$/kg; Exelon cost are 1.7$/kg and 4.85$/kg; Davis Besse cost are 3.9$/kg and 3.09$/kg; Parlo Verde cost are 3.5$/kg and 4.77$/kg; Xcel Energy cost are 3.63$/kg and 0.69$/kg. The cost of hydrogen production using HEEP for Xcel Energy's Prairie Island NPP is 0.69 $/kg. This is because the reactor utilizes High Temperature Steam Electrolysis, method of hydrogen production, while the other methods employs Low Temperature Electrolysis. The results shows that the final price of the hydrogen for each reactor technology depends not only on the production method but also on the cost of the nuclear power plant and the production rate of the hydrogen plant. [Display omitted] • Hydrogen Production, District Heating, Seawater Desalination are some non-electrical applications of nuclear energy. • Nuclear energy has significant potential benefits for producing hydrogen than other conventional methods. • Cost analysis of hydrogen production using nuclear reactors are based on the economics of scale. • HydCalc and HEEP are IAEA program for estimating cost of nuclear hydrogen production. [ABSTRACT FROM AUTHOR]