Publications by authors named "Obed R"

Human exposure to indoor radon has been a subject of continuous concern due to its health implications, especially as it relates to lung cancer. Radon contaminates indoor air quality and poses a significant health threat if not abated/controlled. A seasonal indoor radon assessment of residential buildings of Obafemi Awolowo University was carried out to determine radon seasonal variability and to evaluate the cancer risk to the residents.

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Introduction: Melanosis peritonei is an exceptionally benign condition of uncertain origin marked by the deposition of dark pigments on the peritoneal cavity. It's usually associated with other abnormalities and must be differentiated from metastatic melanoma.

Case Presentation: We report this case of a 67-year-old female presented for abdominal distension for 16 months.

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The distribution of natural radioactivity levels of U, Th, and K in soils overlying the 3 lithologic units within Obafemi Awolowo University, Ile-Ife, Nigeria was investigated to characterize the gamma radiation dose distribution over the lithologies and to assess the radiation hazard due to the natural radionuclides. A thallium-doped cesium iodide detector was employed to determine the activity concentrations of U, Th, and K in 21 soil samples. The respective average concentrations of the 3 radionuclides are 37.

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Objective: The objective of this study was to evaluate the thyroid glands' radiation dose and the risk of thyroid cancer induction from head or neck computed tomography (CT) examinations.

Methods: In a prospective study, we evaluated all participants of all ages and sex referred for Head or Neck CT Scan at the University College Hospital, Ibadan and Me Cure Healthcare Limited, Ibadan, Oyo State, Nigeria. Thyroid radiation dose was estimated with impact scan calculator, and real-time dose measurement with thermoluminescent badge dosimeters (TLDs).

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Objectives: The seriousness and long-term health effects of radon exposure are often underestimated due to inaccurate perceptions of radon risk. The aim of this study was to assess radon risk perception and barriers for residential radon levels testing among Obafemi Awolowo University faculty.

Study Design: A quantitative cross-sectional design was used for this study.

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Radiation dose from natural sources is mainly from exposure to radon in the environment. Radon has its origin from uranium-bearing bedrocks and overburden. In the present study, assessment of the level of radon over the three lithological units upon which the residential areas of ObafemiAwolowo University Campus, Ile-Ife (OAU) was situated was carried out.

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Purpose: In-vivo measurements to determine doses to organs-at-risk can be an essential part of brachytherapy quality assurance (QA). This study compares calculated doses to the rectum with measured dose values as a means of QA in vaginal vault brachytherapy using cylinder applicators.

Material And Methods: At the Department of Radiotherapy, University College Hospital (UCH), Ibadan, Nigeria, intracavitary brachytherapy (ICBT) was delivered by a GyneSource high-dose-rate (HDR) unit with (60)Co.

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Radon measurements were performed in secondary schools in the Oke-Ogun area, South-west, Nigeria, by solid state nuclear track detectors (SSNTDs). About seventy CR-39 detectors were distributed in 35 high schools of the Oke-Ogun area. The CR-39 detectors were exposed in the schools for 3 months and then etched in NaOH 6 N solution at 90 °C for 3 h.

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An indoor radon survey of a total of 77 dwellings randomly selected in 10 districts in Oke-Ogun area of Oyo state, South-western Nigeria was carried out using CR-39 detectors. The CR-39 detectors were placed in the bedrooms and living rooms and exposed for 6 months and then etched in NaOH 6.25 N solution at 90 °C for 3 h.

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CR-39 tracketch detectors were used for the measurement of (222)Rn concentration in 24 offices in Nigeria's oldest university campus in order to estimate the effective dose to the occupants from (222)Rn and its progeny. The dosimetric measurements were made over a period of 3 months. Questionnaires were distributed and analyzed.

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In this study, organ and conceptus doses of patients undergoing chest, abdomen and skull radiograph examinations at two Nigeria X-ray centres, Niger State General Hospital (NGH) and Two-Tees (TTX), are reported. Air kerma was measured, and entrance surface dose (ESD) and half-value layer estimated for each set of tube potential (kV(p)), focus to skin distance and current-time product (mAs) used for each of the patients included in this study. Results show that the mean air kerma in the two centres are similar for the three projections considered in this study.

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The significance of exposure from natural radioactivity in soil and the potential risk for causing health detriment have not received adequate attention in Nigeria. Cancer has become a major cause of mortality in the recent times and now the public interest in the long-term effects of radiation on humans has assumed great prominence following the establishment of a nuclear regulatory body in Nigeria. This study is an effort to investigate a possible relationship between reported cancer incidence and external terrestrial radiation dose level across the six geo-political zones of the country.

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The natural radioactivity concentrations in soil samples collected from 186 locations across 18 cities in the six geo-political zones of Nigeria have been determined using gamma-ray spectrometry. Results show that the concentrations of (40)K, (238)U and (232)Th in the soil samples varied from below detection limits (BDL) to 1459.4 Bq kg(-1) with a mean of 73.

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The current federal and New Jersey State regulations have greatly increased the number of gross alpha and radium tests for public and private drinking water supplies. The determination of radium isotopes in water generally involves lengthy and complicated processes. In this study, a new approach is presented for the determination of gross alpha, 224Ra, 226Ra, and 228Ra activities in water samples.

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Measurements of output dose rates of four Co teletherapy machines located in three hospitals in Nigeria have been made using the facilities of the Secondary Standard Dosimetry Laboratory at Federal Radiation Protection Service in Ibadan, Nigeria, and by applying an International Atomic Energy Agency dosimetric protocol. The results show that the percentage deviation between our measured dose rates and dose rates employed by the users ranged generally between 0.15% and 10.

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A technique has been developed for the measurement of 224Ra, 226Ra, 228Ra, and unsupported 2t2Pb concurrently in a single analysis. The procedure can be applied to both drinking water and wastewater, including the dissolved and suspended fractions of a sample. For drinking water samples, using 3-L aliquots, the radium isotopes are isolated by a fast PbSO4 co-precipitation and then quantified by gamma-ray spectroscopy.

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Entrance surface dose (ESD) measurements have been carried out in Nigeria as part of the ongoing dose reduction programme. Thermoluminescence dosemeters (TLD) were used to measure skin entrance doses for four common radiographic views in three hospitals. The mean ESD for the PA chest examination in all the participating hospitals was in the range 0.

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The general features of occupational radiation protection dosimetry in Nigeria within the period 1990-1999 have been summarised. About 640 personnel, representing about 25% of the estimated number of radiation workers in Nigeria, were monitored by the TL dosimetry technique during the period, with the majority being the personnel of the teaching hospitals across the country. Most private establishments, especially the X ray diagnostic centres, operate without dosimetry coverage or supervision by a regulatory authority.

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