Saleh

Bio: Saleh is an academic researcher from Universiti Teknologi Malaysia. The author has an hindex of 1, co-authored 1 publications receiving 19 citations.

Effective dose from natural background radiation in Keffi and Akwanga towns, central Nigeria

Abstract: Background: Human is exposed to radiaƟ on in their environment with or without their consent; and the exposure to natural background radiaƟ on is an unpreventable event on earth. Materials and Methods: An in situ assessment of the indoor and outdoor background radiaƟ on in Akwanga and Keffi towns of Nasarawa state Nigeria was carried out using a halogen-quenched Geiger Muller (GM) detector (Inspector alert Nuclear radiaƟ on monitor SN: 3544). Each of these towns was divided into at least 20 sampling areas where at least ten readings were taken in order to have a reliable data. Results: The mean indoor and outdoor annual effecƟ ve dose of Akwanga were 1.29± 0.13mSv/yr and 0.31±0.04 mSv/yr respecƟ vely; and that of Keffi were 1.08± 0.15mSv/yr and 0.25±0.04 mSv/yr respecƟ vely. The radiaƟ on levels in both highly populated towns were found to be within the safe limit for areas of normal background set by UNSCEAR (2.4 mSv/yr). Conclusion: These results would serve as a baseline upon which other exposures would be assessed and in the future, serve as reference for dosimetry and decontaminaƟ on in situaƟ ons of radiaƟ on poisoning of these towns.

Health and ecological hazards due to natural radioactivity in soil from mining areas of Nasarawa State, Nigeria

Abstract: Nasarawa State is located in north central Nigeria and it is known as Nigeria's home of solid minerals. It is endowed with barite, copper, zinc, tantalite and granite. Continuous releases of mining waste and tailings into the biosphere may result in a build-up of radionuclides in air, water and soil. This work therefore aims to measure the activity concentration levels of primordial radionuclides in the soil/sediment samples collected from selected mines of the mining areas of Nasarawa State. The paper also assesses the radiological and radio ecological impacts of mining activities on the residents of mining areas and their environment. The activity concentrations of primordial radionuclides ((226)Ra, (232)Th and (40)K) in the surface soils/sediment samples were determined using sodium iodide-thallium gamma spectroscopy. Seven major mines were considered with 21 samples taken from each of the mines for radiochemistry analysis. The human health hazard assessment was conducted using regulatory methodologies set by the United Nations Scientific Committee on the Effects of Atomic Radiation, while the radio ecological impact assessment was conducted using the ERICA tool v. 1.2. The result shows that the activity concentrations of (40)K in the water ways of the Akiri copper and the Azara barite mines are 60 and 67% higher than the world average value for (40)K, respectively. In all mines, the annual effective dose rates (mSv y(-1)) were less than unity, and a maximum annual gonadal dose of 0.58 mSv y(-1) is received at the Akiri copper mine, which is almost twice the world average value for gonadal dose. The external hazard indices for all the mines were less than unity. Our results also show that mollusc-gastropod, insect larvae, mollusc-bivalve and zooplankton are the freshwater biotas with the highest dose rates ranging from 5 to 7 µGy h(-1). These higher dose rates could be associated with zinc and copper mining at Abuni and Akiri, respectively. The most exposed terrestrial reference organisms are lichen and bryophytes. In all cases, the radio ecological risks are not likely to be discernible. This paper presents a pioneer data for ecological risk from ionizing contaminants due to mining activity in Nasarawa State, Nigeria. Its methodology could be adopted for future work on radioecology of mining.

Assessment of outdoor radiation levels and radiological health hazards in Emene Industrial Layout of Enugu State, Nigeria

Abstract: A study to assess the outdoor Background Ionizing Radiation (BIR) levels in Emene Industrial Layout of Enugu State, Nigeria has been conducted. An in-situ measurement of BIR exposure rate in mRh-1 for 30 locations was done using a well calibrated portable GQ GMC-320 PLUS nuclear radiation detector at an elevation of 1.0 m above ground level with a geographical positioning system (GPS) for geographical location. The measured BIR exposure rates were used to evaluate the radiological health hazards and radiation effective doses to different body organs using well established radiological relations. The obtained values were compared with recommended permissible limits to ascertain the radiological health status of the environment. The mean values of BIR exposure levels (0.015±0.001 mRh-1), absorbed dose rates (126.15±5.10 ηGyh-1) and excess lifetime cancer risk (0.541±0.032×10-3) are higher than their recommended safe limits of 0.013 mRh-1, 84.0 ηGyh-1, 0.29×10-3 respectively as recommended by ICRP and UNSCEAR. The mean annual effective dose equivalent (0.155±0.006 mSvy-1) is within recommended permissible limits of 1.00 mSvy-1 for general public exposure. Also, the effective doses to different body organs are all below the recommended limits of 1.0 mSvy-1. Generally, the study shows that Emene Industrial Layout is radiologically contaminated due to industrial activities taking place. However, the contamination does not constitute any immediate radiological health effect on resident of the area but there is the potential for long-term health hazards in the future such as cancer due to accumulated doses. Key words: BIR exposure level, effective dose, industrial activities, Emene Industrial Layout.

Comparative analysis of NORM concentration in mineral soils and tailings from a tin-mine in Nigeria

Abstract: Mining of tin and other related activities have been active and thus leading to economic growth in the Jos area of Nigeria for more than a century. However, mining of minerals has been confirmed to enhance the concentrations of heavy metals and natural radioisotopes in the soil, air and water bodies in the environment. In an attempt to evaluate the radiological burdens resulting from tin mining activities at Rayfield-Du area of Jos, specific activities of naturally occurring radioactive nuclei (238U, 232Th and 40K) concentrations were evaluated in soil samples collected from the mine site. The soil samples were classified as normal soil (S), tailings (T) and mineral soils (M) and their corresponding mean activities for 238U, 232Th and 40K were analysed using an HpGe detector-based gamma spectrometric system. The mean activity concentration for 238U, 232Th and 40K were 323.44, 877.63 and 864.99 Bq/kg, 138.84, 469.31 and 578.65 Bq/kg and 168.83, 436.08 and 346.1 Bq/kg, respectively for M, T and S samples. The calculated radiation dose parameters for the soil samples were all higher than the recommended safety limit. For all the collected soil samples, the external hazard risk Hext were 2.21, 2.81 and 4.44 for S, T and M, respectively while the mean calculated radium equivalent was 819, 1057 and 1645 Bq/kg for S, T, and M, respectively. The excess lifetime cancer risk estimated for the mine was more than the world average value. The radio-ecological dose rate estimate for non-human biota in the mine revealed that all non-human species except lichen and bryophyte had absorbed dose rate less than the 10 µGy/h screening dose.

Assessment of terrestrial gamma radiation dose rate (TGRD) of Kelantan State, Malaysia: Relationship between the geological formation and soil type to radiation dose rate

Abstract: Terrestrial gamma radiation dose rates (TGRD) of Kelantan State were measured in situ using a portable [NaI(TI)] micro roentgen (µR) survey meter. The TGRD rates ranged between 44 and 500 nGy h−1 with a mean value of 209 ± 8 nGy h−1. The distribution of these measurements in various districts of the state shows the statistically the influence of geology and soil types on the dose rate values. The data obtained could be used in formulating safety standard and radiological guidelines.

GIS Mapping and Background Ionizing Radiation (BIR) Assessment of Solid Mineral Mining Sites in Enugu State, Nigeria

Abstract: A study of the external background ionizing radiation (BIR) levels in eight solid mineral mining sites in Enugu State has been carried out using two Digilert radiation monitors Radalart-50 and Radalart-100. Thirty two readings of four samplings in each point were taken at different solid mineral sites of the state following standard procedure. The measured BIR levels obtained ranged from 0.012 mR/hr in Nkpologwu silica mining site to 0.028 mR/hr in clay mining site in Enugu-Ekulu with an average of 0.018 ± 0.004 mR/hr, while the corresponding calculated equivalent dose rate ranged from 1.0 mSv/yr to 2.35 mSv/yr with a mean value of 1.51 ± 0.04 mSv/yr. The result obtained indicates that the average exposure level of the studied area is 38.5% higher than the international standard. This suggests the possibility of the presence of radionuclide in the solid minerals mined in Enugu state. However, the values obtained may not cause immediate health challenge to miners and those engaging in commercial activities around these mining sites in Enugu, but may result in long-term health side-effects to residence and miners who put in over twenty-five years in the job. From the forgoing, it is recommended that control mechanism should be adopted for the members of the public, residence, commercial traders as well as miners working in these sites, and to protect the environment.