Adeseye Arogunjo | Federal University of Technology Akure (original) (raw)

Papers by Adeseye Arogunjo

Research paper thumbnail of Measurement of ground electrical conductivities of different soil type and their effect on growth rate of plant

The purpose of this paper is to examine the contribution of ground electrical conductivity on gro... more The purpose of this paper is to examine the contribution of ground electrical conductivity on growth rate of plants. Wenner array method of measuring ground conductivity has been employed. Three types of soil samples were used for the study; loamy, clayey and sandy soil. The results show that loamy soil has the highest mean conductivity of 3.752x10 -3 (m) -1 followed by clayey with value of 2.121x10 -3 (m) -1 and sandy soil has the least mean conductivity of 4.023x10 -4 (m) -1 . Comparison is made between the present results with those of Hack and both have good agreement. The effect of this parameter on growth rate of three vegetable crops selected for the study; Amaranthus Cruenthus, Amaranthus Tricolar and Solanum Macrocarpon were also investigated. The results show that loamy soil with highest electrical ground conductivity has greatest tendency to support the growth rate of crops.

Research paper thumbnail of Diagnostic Reference Level of Computed Tomography Examinations and Need for Dose Optimization in Ondo State, Nigeria

Iranian Journal of Medical Physics, 2019

Introduction: The present study was conducted to obtain State diagnostic reference levels (DRLs) ... more Introduction: The present study was conducted to obtain State diagnostic reference levels (DRLs) of five routine computed tomography (CT) examinations from two CT centers in Ondo State and to identify factors responsible for dose variation and escalation in these CT centers. Material and Methods: Acquisition parameters and CT dose indices were collected from the storage drives of the two CT centers namely Federal Medical Centre, Owo and Trauma Center, Ondo, Ondo State, Nigeria, for six months on electronic spreadsheets for cranial, sinus, chest, abdomen and pelvis examinations. In addition, dose indices for multiphase examinations were collected to analyze chest and abdominal doses. Wilcoxon rank-sum test was used to assess variations in dose distributions of the two health institutions. Results: The following diagnostic reference levels (DRLs) were obtained at 91 mGy; 1943 mGy.cm, 69 mGy; 1159 mGy.cm, 45 mGy; 1064 mGy.cm, 50 mGy; 2545 mGy.cm and 26 mGy; 622 mGy.cm in cranial, sinus...

Research paper thumbnail of Daily urinary excretion of uranium in members of the public of Southwest Nigeria

Science of The Total Environment, 2011

Research paper thumbnail of Characterization of Dose Rates and Its Internal Fluctuation Using Frequency Distribution Function of Background Radiation Data

The use of distribution function in characterization of data technique, to evaluate and estimate ... more The use of distribution function in characterization of data technique, to evaluate and estimate dose rates from background radiation in Akure informed this study. The mean and fluctuation in mean of possible exposure due to the members of the general public in Akure was deduced by statistically calculating the mean and fluctuation in mean of 166 sample points. Kindenoo blueGeiger PG-15 detector and Garmin GPSmap 62s were used for the research. The Dose Rate (DR) and its internal fluctuation range between 0.16±0.01μSv/h – 0.37±0.04μSv/h in air, and Annual Effective Dose Equivalent, AEDE between 0.31±0.02mSv/y – 0.71±0.08mSv/y; the estimated mean outdoor AEDE 0.50±0.06mSv/y for members of the general public in Akure is below the UNSCEAR and ICRP recommended 1mSv/y annual exposure dose rate. All the estimated AEDE from measured dose rates at the chosen locations have values far lower than the 100mSv limit of admissible low-level radiation. The skewness and kurtosis of DR distribution ...

Research paper thumbnail of Radiometric evaluation of indoor radon levels with influence of building characteristics in residential homes from southwestern Nigeria

Environmental Monitoring and Assessment

Research paper thumbnail of Characterization of Radiation Dose and Soil-to-Plant Transfer Factor of Natural Radionuclides in Some Cities from Southwestern Nigeria and its Effect on Man

Research paper thumbnail of Risk assessment of natural radioactivity in surface water and sediments from a waterfall site in Osun State, Nigeria

Human and Ecological Risk Assessment: An International Journal

Research paper thumbnail of A re-evaluation of the occupancy factors for effective dose estimate in tropical environment

Radiation Protection Dosimetry, 2004

In the estimation of the effective dose to the public, outdoor and indoor occupancy factors have ... more In the estimation of the effective dose to the public, outdoor and indoor occupancy factors have been an important parameter. These factors vary, depending on the prevailing environmental condition in a particular location. The factors have been estimated for the rural and urban areas in Nigeria. An outdoor factor of 0.3 and 0.22 have been estimated for rural and urban dwellers, respectively. The rural outdoor factor is 50% above the value recommended as the world average by the UNSCEAR. The urban outdoor factor is 10% higher than this value. The total outdoor gamma dose rate in the air due to 40 K, 238 U and 232 Th in the soil for some rural population in the southern part of Nigeria is 29.50 AE 3.80 nGy h À1 and the average outdoor effective dose has been estimated to be 54.28 AE 6.95 lSv y À1 using the present occupancy factor.

Research paper thumbnail of Uranium and thorium in soils, mineral sands, water and food samples in a tin mining area in Nigeria with elevated activity

Journal of Environmental Radioactivity, 2009

The activity concentrations of uranium and thorium have been determined in soils and mineral sand... more The activity concentrations of uranium and thorium have been determined in soils and mineral sands from the Nigerian tin mining area of Bisichi, located in the Jos Plateau, and from two control areas in Nigeria (Jos City and Akure) using high-purity germanium detectors (HPGe). High resolution sector field inductively coupled plasma mass spectroscopy (HR-SF-ICP-MS) was used to determine uranium and thorium in liquids and foodstuffs consumed locally in the mining area. The activities of uranium and thorium measured in the soils and mineral sands from Bisichi ranged from 8.7 kBq kg(-1) to 51 kBq kg(-1) for (238)U and from 16.8 kBq kg(-1) to 98 kBq kg(-1) for (232)Th, respectively. These values were significantly higher than those in the control areas of Jos City and Akure and than the reference values reported in the literature. They even exceeded the concentrations reported for areas of high natural radioactive background. Radionuclide concentrations in samples of the local foodstuffs and in water samples collected in Bisichi were found to be higher than UNSCEAR reference values. The results reveal the pollution potential of the mining activities on the surrounding areas.

Research paper thumbnail of Terrestrial Gamma Radiation and the Radiological Implication in South Western Nigeria

Journal of Applied Sciences, 2007

Research paper thumbnail of Dose rate assessment of terrestrial gamma radiation in the Delta region of Nigeria

Radiation Protection Dosimetry

In situ gamma spectroscopy has been employed to characterise natural radiation in the soil at 32 ... more In situ gamma spectroscopy has been employed to characterise natural radiation in the soil at 32 locations in the Delta region of Nigeria. The outdoor gamma dose rates in the air due to 40K, 238U and 232Th in the soil were 1.5 +/- 0.9 nGy h(-1), 6.9 +/- 1.6 nGy h(-1) and 16.3 +/- 3.1 nGy h(-1) respectively. The estimated total annual outdoor effective dose to the people in the region was 31.6 microSv y(-1).

Research paper thumbnail of Effect of Communication Component Disposal on Soil Radioactivity and its Health Implication

Experimental investigation was carried out on soil samples from two urban areas of Oyo State wher... more Experimental investigation was carried out on soil samples from two urban areas of Oyo State where disposed communication components were discovered and one rural area where not much remnants of communication component were found. Natural radionuclide concentration was determined by gamma ray spectrometry (HpGe detector). Spectral analyses were performed with the Genie2k spectrometry software, version 2.1. Library of radionuclide, containing the energy of the characteristic gamma peaks for each nuclide analysed and their corresponding emission probabilities were built from the data supplied in the software. Specific activities were obtained for 40K, 208Tl, 210Pb, 212Bi, 212Pb, 214Bi, 214Pb, 224Ra, 226Ra, 228Ac, 228Th, 234MPa, 234Th, 235U and 137Cs. Calculated outdoor gamma radiation absorbed dose rate in air due to each of the primordial radionuclide ranged from 25.77 ± 0.67 nGyh-1 for 40K to 3.25 ± 0.21 nGyh-1 for 208Tl(indicator for 232Th). Average absorbed dose rate in air for th...

Research paper thumbnail of Assessment of Activity Concentration of Radionuclides in Sediment from Oil Producing Communities of Delta State, Nigeria

Journal of Environmental Protection, 2015

Activity concentrations of twenty-six (26) samples of sediment collected from rivers from eleven ... more Activity concentrations of twenty-six (26) samples of sediment collected from rivers from eleven (11) oil-producing communities and two (2) non-oil producing communities in Delta state of Nigeria were studied. Hyper Purity Germanium (HPGe) Detector was used for counting and detection of radionuclide content of all samples. Results of the samples analysed showed that the radioactivity concentrations of K40, Th232 and U238 in the sediment samples from oil-producing areas range from 32.47 Bq·kg-1 to 525.1 Bq·kg-1 with an average of 302.15 Bq·kg-1, 6.31 Bq·kg-1 to 19.33 Bq·kg-1 with an average of 11.66 Bq·kg-1, and 4.45 Bq·kg-1 to 18.69 Bq·kg-1 with an average of 8.66 Bq·kg-1 respectively. Activity concentrations at the control site ranged from 3.15 Bq·kg-1 to 4.80 Bq·kg-1, 2.27 Bq·kg-1 to 4.18 Bq·kg-1 and 1.15 Bq·kg-1 to 1.76 Bq·kg-1 for K40, Th232 and U238. These values are within the world average; natural radioactivity mapping of the study area is carried out using the Surfer software.

Research paper thumbnail of Measurement of Ground Electrical Conductivities of Different Soil Type and Their Effect on Growth Rate of Plant

The purpose of this paper is to examine the contribution of ground electrical conductivity on gro... more The purpose of this paper is to examine the contribution of ground electrical conductivity on growth rate of plants. Wenner array method of measuring ground conductivity has been employed. Three types of soil samples were used for the study; loamy, clayey and sandy soil. The results show that loamy soil has the highest mean conductivity of 3.752x10 -3 (Ωm)-1 followed

Research paper thumbnail of Heavy Metal Composition of Some Solid Minerals in Nigeria and Their Health Implications to the Environment

Pakistan Journal of Biological Sciences, 2007

Heavy metals overload taken via ingestion, inhalation and dermal have been found to be detrimenta... more Heavy metals overload taken via ingestion, inhalation and dermal have been found to be detrimental to both the occupationally exposed group and member of the public. The body burden of these metals has been a source of concern in environmental safety regulatory programs. The risk factor becomes potentially high in an environment where regulatory safety criteria are either neglected or not available. The implication of indiscriminate or unregulated mining activities has been pointed out as a major risk to public health. In order to assess the potential toxicological and radiological health hazard posed to the environment due to mining activities in Nigeria, solid mineral ores (iron, tin and tantalite) from south-western and north-central (Kogi and Ekiti States) part of the country were analysed for their trace-metal contents. The analysis was performed using Energy Dispersive X-Ray Fluorescence (EDXRF) analyses spanning several months between 2005 and 2006. The samples were found to contain some major, minor and trace elements of varying concentrations. The elements reported here are K, Ca, Ti, V, Cr, Mn, Fe, Ni, Sr, Y, Zr, Nb, Sn, Ta, Re, Th, U, Sc, Cd, Bi, Ra and Zn. Toxic metal of serious environmental and public concern like Cadmium was detected. The possibility of altering heavy metal constituents of the natural ecosystem as a result of mining activities and the implications of such alterations has been enumerated. Possible pathway into the food chain as a result of mining activity has also been presented.

Research paper thumbnail of Design and Construction of an Infrared Activated Entrance and Exit Counting Device

Nigeria Journal of Pure and Applied Physics, 2003

ABSTRACT

Research paper thumbnail of Measurement of Ground Electrical Conductivity for Planning Medium Wave Radio Broadcast Stations in South Western Nigeria

Nigeria Journal of Pure and Applied Physics, 2000

... frequency of the wave, then ~ ' A State Broadcasting Service, Ifaki-Ekiti on Q'? = ... more ... frequency of the wave, then ~ ' A State Broadcasting Service, Ifaki-Ekiti on Q'? = jn)EAE, A (4) frequency 549 kHz, Ondo Radio Corporation at at _ . Irese on frequency 531 kHz, Oba-lle on 711 kHz, ThuS> °q“at'°n (2) b°9°m6s_ Okitipupa on 765 kH_z, and Ido—Ani on 1035 kHa. ...

Research paper thumbnail of Daily urinary excretion of uranium in members of the public of Southwest Nigeria

Science of The Total Environment, 2011

The main aim of this study was to determine and evaluate urinary excretion values of uranium in m... more The main aim of this study was to determine and evaluate urinary excretion values of uranium in members of the public of Southwest Nigeria living in areas of low environmental uranium. As several uranium mines are running in Nigeria and the operations could be a risk of contamination for the workers as well as for the members of the public, biomonitoring of urine could provide information about the exposure to uranium for the subjects. Therefore, baseline values of uranium in urine are needed from subjects living in areas without mining activities. Volunteers of both genders (age range 3 to 78 years) were asked to collect 24h-urine samples. The concentration measurements of uranium in urine were performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). In addition, urinary creatinine values were determined for normalization of the renal uranium relative to the creatinine concentrations. The urinary uranium concentrations and their creatinine normalized values ranged from <10.4 to 150 ng L(-1) (median 13.8 ng L(-1)) and from 2.52 to 252.7 ng g(-1) creatinine (median 33.4 ng g(-1) creatinine), respectively, for adult subjects above 15 years of both genders. An increased uranium excretion value of 61.6 ng L(-1) (median), and of 76.0 ng g(-1) creatinine, respectively, were found in young subjects below 15 years. The median of daily excreted uranium was estimated to be 14.2 ng d(-1) for adults and of 45.1 ng d(-1) for children, respectively. The uranium excretion from males and females living in Nigeria in a non-mining area was comparable to reference values reported from other countries with low level of environmental uranium. The data can be considered as baseline values of urinary uranium in unexposed subjects in Nigeria.

Research paper thumbnail of A technique for the determination of ruthenium stable isotopes in urine samples

Journal of Radioanalytical and Nuclear Chemistry, 2007

Proton activation analysis has been recently applied for the determination of stable isotopes of ... more Proton activation analysis has been recently applied for the determination of stable isotopes of trace metals in blood plasma samples taken from volunteers during tracer kinetic studies. The very low values of intestinal uptake for some elements, like ruthenium, make the kinetics of the excretion crucial for interpreting the bioassay data. Therefore, a procedure has been developed to process urine samples in order to have proper targets for the activation with protons. Preliminary tests with Ru-doped samples, conducted using the MC-40 Cyclotron at JRC Ispra, has confirmed the feasibility of the method. The minimum detectable concentrations, in the current operating conditions, are 16 ng 99 Ru . ml -1 and 0.5 ng 101 Ru . ml -1 .

Research paper thumbnail of Effect of Geology on Soil Radioactivity and Risks to Humans Based on Data from Several Towns in Nigeria

Environmental Forensics, 2013

Gamma ray spectrometric technique has been used to determine activity concentrations of some prim... more Gamma ray spectrometric technique has been used to determine activity concentrations of some primordial radionuclides in the naturally occurring uranium, actinium and thorium series and of non-series 40 K in soil samples collected from five major towns in Oyo State, Southwestern Nigeria. Activity concentration determination was done using a high purity germanium (HPGe) detector. It ranged from 85.83 ± 4.04 Bq kg −1 to 1,850.60 ± 36.83 Bq kg −1 for 40 K; 5.23 ± 0.34 Bq kg −1 to 198.31 ± 4.10 Bq kg −1 for 208 Tl (indicator for 232 Th) and 7.82 ± 0.42 Bq kg −1 to 64.65 ± 2.00 Bq kg −1 for 214 Bi (indicator for 238 U). The outdoor absorbed dose rate in air due to each of the primordial radionuclides was calculated from the mean values of the activity concentration in each sample. Values ranged from 3.60 ± 0.17 nGy h −1 to 77.73 ± 1.55 nGy h −1 for 40 K, 3.48 ± 0.23 nGy h −1 to 132.07 ± 2.73 nGy h −1 for 208 Tl and 3.35 ± 0.21 nGy h −1 to 27.73 ± 0.86 nGy h −1 for 214 Bi. The absorbed dose rate in air was the highest for rocky areas, while the lowest value came from non-rocky, non-industrialized areas. The estimated annual outdoor effective dose equivalents for the two rocky areas were 385.76 μSv y −1 and 221.28 μSv y −1 . The estimated annual outdoor effective dose equivalents for the two industrialized areas were 64.05 μSv y −1 and 47.65 μSv y −1 . The value for non-rocky, non-industrialized areas was 19.19 μSv y −1 . The average value for the study area was 147.59 μSv y −1 . The estimated collective effective dose equivalent for the area was 9.77 × 10 2 man-Sv y −1 . The expected number of people in the study area at risk of incurring cancer per year as a result of radioactivity in the soil was estimated to be 11; this value represents approximately 7% of the estimated 160 people for 18 Nigerian cities, approximately 69% of 16 people estimated for oil producing areas of Nigeria and less than the United States Environmental Protection Agency regulatory limit of 1 cancer case to 10,000 people. Also, this result shows that local variability of natural radionuclides in soil depends on local geology of the area. The incidence number was 2.4 people per million.

Research paper thumbnail of Measurement of ground electrical conductivities of different soil type and their effect on growth rate of plant

The purpose of this paper is to examine the contribution of ground electrical conductivity on gro... more The purpose of this paper is to examine the contribution of ground electrical conductivity on growth rate of plants. Wenner array method of measuring ground conductivity has been employed. Three types of soil samples were used for the study; loamy, clayey and sandy soil. The results show that loamy soil has the highest mean conductivity of 3.752x10 -3 (m) -1 followed by clayey with value of 2.121x10 -3 (m) -1 and sandy soil has the least mean conductivity of 4.023x10 -4 (m) -1 . Comparison is made between the present results with those of Hack and both have good agreement. The effect of this parameter on growth rate of three vegetable crops selected for the study; Amaranthus Cruenthus, Amaranthus Tricolar and Solanum Macrocarpon were also investigated. The results show that loamy soil with highest electrical ground conductivity has greatest tendency to support the growth rate of crops.

Research paper thumbnail of Diagnostic Reference Level of Computed Tomography Examinations and Need for Dose Optimization in Ondo State, Nigeria

Iranian Journal of Medical Physics, 2019

Introduction: The present study was conducted to obtain State diagnostic reference levels (DRLs) ... more Introduction: The present study was conducted to obtain State diagnostic reference levels (DRLs) of five routine computed tomography (CT) examinations from two CT centers in Ondo State and to identify factors responsible for dose variation and escalation in these CT centers. Material and Methods: Acquisition parameters and CT dose indices were collected from the storage drives of the two CT centers namely Federal Medical Centre, Owo and Trauma Center, Ondo, Ondo State, Nigeria, for six months on electronic spreadsheets for cranial, sinus, chest, abdomen and pelvis examinations. In addition, dose indices for multiphase examinations were collected to analyze chest and abdominal doses. Wilcoxon rank-sum test was used to assess variations in dose distributions of the two health institutions. Results: The following diagnostic reference levels (DRLs) were obtained at 91 mGy; 1943 mGy.cm, 69 mGy; 1159 mGy.cm, 45 mGy; 1064 mGy.cm, 50 mGy; 2545 mGy.cm and 26 mGy; 622 mGy.cm in cranial, sinus...

Research paper thumbnail of Daily urinary excretion of uranium in members of the public of Southwest Nigeria

Science of The Total Environment, 2011

Research paper thumbnail of Characterization of Dose Rates and Its Internal Fluctuation Using Frequency Distribution Function of Background Radiation Data

The use of distribution function in characterization of data technique, to evaluate and estimate ... more The use of distribution function in characterization of data technique, to evaluate and estimate dose rates from background radiation in Akure informed this study. The mean and fluctuation in mean of possible exposure due to the members of the general public in Akure was deduced by statistically calculating the mean and fluctuation in mean of 166 sample points. Kindenoo blueGeiger PG-15 detector and Garmin GPSmap 62s were used for the research. The Dose Rate (DR) and its internal fluctuation range between 0.16±0.01μSv/h – 0.37±0.04μSv/h in air, and Annual Effective Dose Equivalent, AEDE between 0.31±0.02mSv/y – 0.71±0.08mSv/y; the estimated mean outdoor AEDE 0.50±0.06mSv/y for members of the general public in Akure is below the UNSCEAR and ICRP recommended 1mSv/y annual exposure dose rate. All the estimated AEDE from measured dose rates at the chosen locations have values far lower than the 100mSv limit of admissible low-level radiation. The skewness and kurtosis of DR distribution ...

Research paper thumbnail of Radiometric evaluation of indoor radon levels with influence of building characteristics in residential homes from southwestern Nigeria

Environmental Monitoring and Assessment

Research paper thumbnail of Characterization of Radiation Dose and Soil-to-Plant Transfer Factor of Natural Radionuclides in Some Cities from Southwestern Nigeria and its Effect on Man

Research paper thumbnail of Risk assessment of natural radioactivity in surface water and sediments from a waterfall site in Osun State, Nigeria

Human and Ecological Risk Assessment: An International Journal

Research paper thumbnail of A re-evaluation of the occupancy factors for effective dose estimate in tropical environment

Radiation Protection Dosimetry, 2004

In the estimation of the effective dose to the public, outdoor and indoor occupancy factors have ... more In the estimation of the effective dose to the public, outdoor and indoor occupancy factors have been an important parameter. These factors vary, depending on the prevailing environmental condition in a particular location. The factors have been estimated for the rural and urban areas in Nigeria. An outdoor factor of 0.3 and 0.22 have been estimated for rural and urban dwellers, respectively. The rural outdoor factor is 50% above the value recommended as the world average by the UNSCEAR. The urban outdoor factor is 10% higher than this value. The total outdoor gamma dose rate in the air due to 40 K, 238 U and 232 Th in the soil for some rural population in the southern part of Nigeria is 29.50 AE 3.80 nGy h À1 and the average outdoor effective dose has been estimated to be 54.28 AE 6.95 lSv y À1 using the present occupancy factor.

Research paper thumbnail of Uranium and thorium in soils, mineral sands, water and food samples in a tin mining area in Nigeria with elevated activity

Journal of Environmental Radioactivity, 2009

The activity concentrations of uranium and thorium have been determined in soils and mineral sand... more The activity concentrations of uranium and thorium have been determined in soils and mineral sands from the Nigerian tin mining area of Bisichi, located in the Jos Plateau, and from two control areas in Nigeria (Jos City and Akure) using high-purity germanium detectors (HPGe). High resolution sector field inductively coupled plasma mass spectroscopy (HR-SF-ICP-MS) was used to determine uranium and thorium in liquids and foodstuffs consumed locally in the mining area. The activities of uranium and thorium measured in the soils and mineral sands from Bisichi ranged from 8.7 kBq kg(-1) to 51 kBq kg(-1) for (238)U and from 16.8 kBq kg(-1) to 98 kBq kg(-1) for (232)Th, respectively. These values were significantly higher than those in the control areas of Jos City and Akure and than the reference values reported in the literature. They even exceeded the concentrations reported for areas of high natural radioactive background. Radionuclide concentrations in samples of the local foodstuffs and in water samples collected in Bisichi were found to be higher than UNSCEAR reference values. The results reveal the pollution potential of the mining activities on the surrounding areas.

Research paper thumbnail of Terrestrial Gamma Radiation and the Radiological Implication in South Western Nigeria

Journal of Applied Sciences, 2007

Research paper thumbnail of Dose rate assessment of terrestrial gamma radiation in the Delta region of Nigeria

Radiation Protection Dosimetry

In situ gamma spectroscopy has been employed to characterise natural radiation in the soil at 32 ... more In situ gamma spectroscopy has been employed to characterise natural radiation in the soil at 32 locations in the Delta region of Nigeria. The outdoor gamma dose rates in the air due to 40K, 238U and 232Th in the soil were 1.5 +/- 0.9 nGy h(-1), 6.9 +/- 1.6 nGy h(-1) and 16.3 +/- 3.1 nGy h(-1) respectively. The estimated total annual outdoor effective dose to the people in the region was 31.6 microSv y(-1).

Research paper thumbnail of Effect of Communication Component Disposal on Soil Radioactivity and its Health Implication

Experimental investigation was carried out on soil samples from two urban areas of Oyo State wher... more Experimental investigation was carried out on soil samples from two urban areas of Oyo State where disposed communication components were discovered and one rural area where not much remnants of communication component were found. Natural radionuclide concentration was determined by gamma ray spectrometry (HpGe detector). Spectral analyses were performed with the Genie2k spectrometry software, version 2.1. Library of radionuclide, containing the energy of the characteristic gamma peaks for each nuclide analysed and their corresponding emission probabilities were built from the data supplied in the software. Specific activities were obtained for 40K, 208Tl, 210Pb, 212Bi, 212Pb, 214Bi, 214Pb, 224Ra, 226Ra, 228Ac, 228Th, 234MPa, 234Th, 235U and 137Cs. Calculated outdoor gamma radiation absorbed dose rate in air due to each of the primordial radionuclide ranged from 25.77 ± 0.67 nGyh-1 for 40K to 3.25 ± 0.21 nGyh-1 for 208Tl(indicator for 232Th). Average absorbed dose rate in air for th...

Research paper thumbnail of Assessment of Activity Concentration of Radionuclides in Sediment from Oil Producing Communities of Delta State, Nigeria

Journal of Environmental Protection, 2015

Activity concentrations of twenty-six (26) samples of sediment collected from rivers from eleven ... more Activity concentrations of twenty-six (26) samples of sediment collected from rivers from eleven (11) oil-producing communities and two (2) non-oil producing communities in Delta state of Nigeria were studied. Hyper Purity Germanium (HPGe) Detector was used for counting and detection of radionuclide content of all samples. Results of the samples analysed showed that the radioactivity concentrations of K40, Th232 and U238 in the sediment samples from oil-producing areas range from 32.47 Bq·kg-1 to 525.1 Bq·kg-1 with an average of 302.15 Bq·kg-1, 6.31 Bq·kg-1 to 19.33 Bq·kg-1 with an average of 11.66 Bq·kg-1, and 4.45 Bq·kg-1 to 18.69 Bq·kg-1 with an average of 8.66 Bq·kg-1 respectively. Activity concentrations at the control site ranged from 3.15 Bq·kg-1 to 4.80 Bq·kg-1, 2.27 Bq·kg-1 to 4.18 Bq·kg-1 and 1.15 Bq·kg-1 to 1.76 Bq·kg-1 for K40, Th232 and U238. These values are within the world average; natural radioactivity mapping of the study area is carried out using the Surfer software.

Research paper thumbnail of Measurement of Ground Electrical Conductivities of Different Soil Type and Their Effect on Growth Rate of Plant

The purpose of this paper is to examine the contribution of ground electrical conductivity on gro... more The purpose of this paper is to examine the contribution of ground electrical conductivity on growth rate of plants. Wenner array method of measuring ground conductivity has been employed. Three types of soil samples were used for the study; loamy, clayey and sandy soil. The results show that loamy soil has the highest mean conductivity of 3.752x10 -3 (Ωm)-1 followed

Research paper thumbnail of Heavy Metal Composition of Some Solid Minerals in Nigeria and Their Health Implications to the Environment

Pakistan Journal of Biological Sciences, 2007

Heavy metals overload taken via ingestion, inhalation and dermal have been found to be detrimenta... more Heavy metals overload taken via ingestion, inhalation and dermal have been found to be detrimental to both the occupationally exposed group and member of the public. The body burden of these metals has been a source of concern in environmental safety regulatory programs. The risk factor becomes potentially high in an environment where regulatory safety criteria are either neglected or not available. The implication of indiscriminate or unregulated mining activities has been pointed out as a major risk to public health. In order to assess the potential toxicological and radiological health hazard posed to the environment due to mining activities in Nigeria, solid mineral ores (iron, tin and tantalite) from south-western and north-central (Kogi and Ekiti States) part of the country were analysed for their trace-metal contents. The analysis was performed using Energy Dispersive X-Ray Fluorescence (EDXRF) analyses spanning several months between 2005 and 2006. The samples were found to contain some major, minor and trace elements of varying concentrations. The elements reported here are K, Ca, Ti, V, Cr, Mn, Fe, Ni, Sr, Y, Zr, Nb, Sn, Ta, Re, Th, U, Sc, Cd, Bi, Ra and Zn. Toxic metal of serious environmental and public concern like Cadmium was detected. The possibility of altering heavy metal constituents of the natural ecosystem as a result of mining activities and the implications of such alterations has been enumerated. Possible pathway into the food chain as a result of mining activity has also been presented.

Research paper thumbnail of Design and Construction of an Infrared Activated Entrance and Exit Counting Device

Nigeria Journal of Pure and Applied Physics, 2003

ABSTRACT

Research paper thumbnail of Measurement of Ground Electrical Conductivity for Planning Medium Wave Radio Broadcast Stations in South Western Nigeria

Nigeria Journal of Pure and Applied Physics, 2000

... frequency of the wave, then ~ ' A State Broadcasting Service, Ifaki-Ekiti on Q'? = ... more ... frequency of the wave, then ~ ' A State Broadcasting Service, Ifaki-Ekiti on Q'? = jn)EAE, A (4) frequency 549 kHz, Ondo Radio Corporation at at _ . Irese on frequency 531 kHz, Oba-lle on 711 kHz, ThuS> °q“at'°n (2) b°9°m6s_ Okitipupa on 765 kH_z, and Ido—Ani on 1035 kHa. ...

Research paper thumbnail of Daily urinary excretion of uranium in members of the public of Southwest Nigeria

Science of The Total Environment, 2011

The main aim of this study was to determine and evaluate urinary excretion values of uranium in m... more The main aim of this study was to determine and evaluate urinary excretion values of uranium in members of the public of Southwest Nigeria living in areas of low environmental uranium. As several uranium mines are running in Nigeria and the operations could be a risk of contamination for the workers as well as for the members of the public, biomonitoring of urine could provide information about the exposure to uranium for the subjects. Therefore, baseline values of uranium in urine are needed from subjects living in areas without mining activities. Volunteers of both genders (age range 3 to 78 years) were asked to collect 24h-urine samples. The concentration measurements of uranium in urine were performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). In addition, urinary creatinine values were determined for normalization of the renal uranium relative to the creatinine concentrations. The urinary uranium concentrations and their creatinine normalized values ranged from <10.4 to 150 ng L(-1) (median 13.8 ng L(-1)) and from 2.52 to 252.7 ng g(-1) creatinine (median 33.4 ng g(-1) creatinine), respectively, for adult subjects above 15 years of both genders. An increased uranium excretion value of 61.6 ng L(-1) (median), and of 76.0 ng g(-1) creatinine, respectively, were found in young subjects below 15 years. The median of daily excreted uranium was estimated to be 14.2 ng d(-1) for adults and of 45.1 ng d(-1) for children, respectively. The uranium excretion from males and females living in Nigeria in a non-mining area was comparable to reference values reported from other countries with low level of environmental uranium. The data can be considered as baseline values of urinary uranium in unexposed subjects in Nigeria.

Research paper thumbnail of A technique for the determination of ruthenium stable isotopes in urine samples

Journal of Radioanalytical and Nuclear Chemistry, 2007

Proton activation analysis has been recently applied for the determination of stable isotopes of ... more Proton activation analysis has been recently applied for the determination of stable isotopes of trace metals in blood plasma samples taken from volunteers during tracer kinetic studies. The very low values of intestinal uptake for some elements, like ruthenium, make the kinetics of the excretion crucial for interpreting the bioassay data. Therefore, a procedure has been developed to process urine samples in order to have proper targets for the activation with protons. Preliminary tests with Ru-doped samples, conducted using the MC-40 Cyclotron at JRC Ispra, has confirmed the feasibility of the method. The minimum detectable concentrations, in the current operating conditions, are 16 ng 99 Ru . ml -1 and 0.5 ng 101 Ru . ml -1 .

Research paper thumbnail of Effect of Geology on Soil Radioactivity and Risks to Humans Based on Data from Several Towns in Nigeria

Environmental Forensics, 2013

Gamma ray spectrometric technique has been used to determine activity concentrations of some prim... more Gamma ray spectrometric technique has been used to determine activity concentrations of some primordial radionuclides in the naturally occurring uranium, actinium and thorium series and of non-series 40 K in soil samples collected from five major towns in Oyo State, Southwestern Nigeria. Activity concentration determination was done using a high purity germanium (HPGe) detector. It ranged from 85.83 ± 4.04 Bq kg −1 to 1,850.60 ± 36.83 Bq kg −1 for 40 K; 5.23 ± 0.34 Bq kg −1 to 198.31 ± 4.10 Bq kg −1 for 208 Tl (indicator for 232 Th) and 7.82 ± 0.42 Bq kg −1 to 64.65 ± 2.00 Bq kg −1 for 214 Bi (indicator for 238 U). The outdoor absorbed dose rate in air due to each of the primordial radionuclides was calculated from the mean values of the activity concentration in each sample. Values ranged from 3.60 ± 0.17 nGy h −1 to 77.73 ± 1.55 nGy h −1 for 40 K, 3.48 ± 0.23 nGy h −1 to 132.07 ± 2.73 nGy h −1 for 208 Tl and 3.35 ± 0.21 nGy h −1 to 27.73 ± 0.86 nGy h −1 for 214 Bi. The absorbed dose rate in air was the highest for rocky areas, while the lowest value came from non-rocky, non-industrialized areas. The estimated annual outdoor effective dose equivalents for the two rocky areas were 385.76 μSv y −1 and 221.28 μSv y −1 . The estimated annual outdoor effective dose equivalents for the two industrialized areas were 64.05 μSv y −1 and 47.65 μSv y −1 . The value for non-rocky, non-industrialized areas was 19.19 μSv y −1 . The average value for the study area was 147.59 μSv y −1 . The estimated collective effective dose equivalent for the area was 9.77 × 10 2 man-Sv y −1 . The expected number of people in the study area at risk of incurring cancer per year as a result of radioactivity in the soil was estimated to be 11; this value represents approximately 7% of the estimated 160 people for 18 Nigerian cities, approximately 69% of 16 people estimated for oil producing areas of Nigeria and less than the United States Environmental Protection Agency regulatory limit of 1 cancer case to 10,000 people. Also, this result shows that local variability of natural radionuclides in soil depends on local geology of the area. The incidence number was 2.4 people per million.