Journal of Radioanalytical and Nuclear Chemistry, 2011
... These values are similar to that obtained for tailings samples by Boadu in 2001 [19] and for ... more ... These values are similar to that obtained for tailings samples by Boadu in 2001 [19] and for river sediments by Nyarko in 2003 [20] at other mining areas in Ghana. The similarity is due to the com-mon geological features (arsenopyrite) shared by the
Journal of Radioanalytical and Nuclear Chemistry, 2012
ABSTRACT Studies have been carried out on the distribution of major and trace elements concentrat... more ABSTRACT Studies have been carried out on the distribution of major and trace elements concentrations in oxide and sulphide feed ores at various stages of milling and processing of gold in a goldmine at Bogoso in the western region of Ghana. The studies evaluated concentration enhancements at various stages of treatment with emphasis on understanding the typical processes leading to enhancement of concentration at each stage and ultimately the impact from discharges into the surrounding environment. The feed ore samples were analyzed using energy dispersive X-ray fluorescence spectrometry. The results show concentration enhancements of a significant number of elements at some stages of processing in the two processing plants with the highest number of elements with enhanced concentrations coming from chemically treated media of both plants. Though there are relatively high concentrations of V (max.: 284 ppm), Cr (max.: 149 ppm), Co (max.: 84 ppm), and U (max.: 26.8 ppm) at the discharge points, the concentrations of most of the toxic elements in the slurries discharged into the tailings dam are mostly within their respective world averages. The enrichment indices computed for the slurries being discharged into the tailings dam suggests that the dam is not enriched with the toxic elements Cr, Co, Ni, Zn, Cu and Pb. The enrichment index of the slurries discharged into the tailings dam decreases in the order of oxide plant > sulphide plant. Principal component analyses performed suggest that Al2O3, K2O, Co, Zn, Cu, Y and Zr are geochemically associated. Results from the studies also suggest that the discharge of these elements into the tailings dam may contribute insignificant pollution of the surrounding area.
The possible environmental impacts of naturally occurring radionuclides on workers and a critical... more The possible environmental impacts of naturally occurring radionuclides on workers and a critical community, as a result of milling and processing sulfide ores for gold by a mining company at Bogoso in the western region of Ghana, have been investigated using gamma spectroscopy. Indicative doses for the workers during sulfide ore processing were calculated from the activity concentrations measured at both physical and chemical processing stages. The dose rate, annual effective dose equivalent, radium equivalent activity, external and internal hazard indices, and radioactivity level index for tailings, for the de-silted sediments of run-off from the vicinity of the tailings dam through the critical community, and for the soils of the critical community's basic schools were calculated and found to be lower than their respective permissible limits. The environmental impact of the radionuclides is therefore expected to be low in this mining environment.
The safety culture of selected practices and facilities in Ghana utilising radiation sources or r... more The safety culture of selected practices and facilities in Ghana utilising radiation sources or radiation emitting devices has been assessed using a performance indicator, which provided status information on management and operating staff commitment to safety. The questionnaire was based on the following broad areas: general safety considerations, safety policy at the facility level, safety practices at the facility level, definition of responsibility, staff training, safety of the physical structure of the facility and the emergency plans. The analysis showed that the percentage levels of commitment to safety for the respective practices are as follows: conventional radiography, 23.3-90.0%; research reactor, 73.3%; gamma irradiation facility, 53.3%; radiotherapy, 76.7%; X-ray scanner, 80.0%; gamma scanner, 76.7%; industrial radiography 86.7% and nuclear density practice, 78%. None of the practices or facilities was able to satisfy all the requirements that will ensure a 100% level of safety culture.
Journal of Radioanalytical and Nuclear Chemistry, 2015
ABSTRACT Dear Editor-in-Chief,We appreciate the letter written by Dr. M. U. Khandaker, drawing ou... more ABSTRACT Dear Editor-in-Chief,We appreciate the letter written by Dr. M. U. Khandaker, drawing our attention to some aspects in our publication he thought needed to be addressed. We however disagreed with most of the issues he raised and our responses are as follows:He thought the minimum detectable activity (MDA) value for K is too low, the counting time was too short based on his experience and why distilled water was used. First of all the distilled water was used to limit the level of backscatter radiation within the detector system during the background count. Also, we want to state that a low background spectrometry system was used for the counting. In other to optimize the result of the background count and the real samples, the same counting time was used. We agree that the longer the counting time the greater the peak area, however, based on the prevailing laboratory condition which could not enable us to consider a longer counting time 36,000 was used which could also give an apprec ...
Journal of Radioanalytical and Nuclear Chemistry, 2012
Abstract Knowledge of radioactivity levels in human diet is of particular concern for the estimat... more Abstract Knowledge of radioactivity levels in human diet is of particular concern for the estimation of possible radiological hazards to human health. However, very few surveys of radioactivity in food have been conducted in Ghana. The natural radionuclides 226 Ra, ...
ABSTRACT Studies were conducted in the vicinity of a gold processing plant at Tarkwa (Western Reg... more ABSTRACT Studies were conducted in the vicinity of a gold processing plant at Tarkwa (Western Region, Ghana) to obtain baseline radioactivity data prior to the installation of Cs-137 nuclear density gauges for quality control measure-ment of the density of slurry in the pipelines at the plant. A survey meter, gamma spectrometry and alpha-guard were used to obtain data on radionuclide concentrations in the environment, and determine the effective dose to workers. The results indicated the absence of any artificial radioactivity within the environs of the plant. The levels of Cs-137 before installing the gauges were within the detection limit of 1.5 Bq/kg. The effective doses estimated from the naturally occurring radionuclides were within the limits set by International Commission on Radiological Protection. Journal of Applied Science and Technology Vol. 12 (1&2) 2007: pp. 18-24
Journal of Radioanalytical and Nuclear Chemistry, 2014
ABSTRACT Direct gamma spectrometry study was carried out within lower basin of river Pra to ascer... more ABSTRACT Direct gamma spectrometry study was carried out within lower basin of river Pra to ascertain the baseline radioactivity levels of naturally occurring radioactive materials. The average activity concentrations of U-238, Th-232 and K-40 in the soil and sediment were 25.51, 28.04 and 238.98 Bqkg(-1) for soil, and 16.02, 20.31 and 27.39 Bqkg(-1) for the sediment. The study indicated that the activity concentrations of U-238, Th-232 and K-40 in the water were calculated to be 2.51, 1.71 and 41.43 BqL(-1), respectively and the corresponding annual effective dose ranged from 0.35 to 3.91 with an average of 1.82 mu Svyear(-1). These values are within the levels allowed elsewhere or recommended by the WHO.
Radioactivity concentration of Naturally Occurring Radioactive Materials (NORMs) in shore sedimen... more Radioactivity concentration of Naturally Occurring Radioactive Materials (NORMs) in shore sediments (samples) collected along the coast of Accra were analyzed using a gamma spectrometry with a high purity germanium detector. The specific activity concentrations range from 8.60 Bqkg -1 to 61.01 Bqkg -1 with a mean of 29.78 Bqkg -1 for 40 K, 0.62 Bqkg -1 to 148.80 Bqkg -1 with a mean of 22.04 Bqkg -1 for 226 Ra and 0.17 Bqkg -1 to 732.60 Bqkg -1 with a mean of 108.60 Bqkg -1 for 232 Th. The 40 K concentration compares well with the world average value while that for 226 Ra and 232 Th does not. The average absorbed dose rate was estimated to range from 0.75 nGyh -1 to 509.38 nGyh -1 with an average of 77.02 nGyh -1 , while the average annual effective dose also ranged from 0.00 mSvy -1 to 0.63 mSvy -1 with an average of 0.09 mSvy -1 was also estimated. The average radium equivalent activity and average external hazard index were also estimated to be 9.00 Bqkg -1 and 0.48 respectively a...
Radiometric determinations have been carried out to assess public exposure to radioactivity for c... more Radiometric determinations have been carried out to assess public exposure to radioactivity for communities along the coast of a shallow water offshore oilfield in Ghana (which started their operations recently) in order to establish baseline data using alpha spectrometry after radiochemical separation and non-destructive gamma spectrometry. The average activity concentrations of (234)U, (238)U, (230)Th and (232)Th by alpha-particle spectrometry and of (226)Ra, (228)Ra, (228)Th, (40)K, (210)Pb, (234)Th and (137)Cs by gamma-ray spectrometry were determined in the soil samples. The activity concentrations of (234)U, (238)U, (230)Th and (232)Th were determined in the water samples by alpha-particle spectrometry and of (226)Ra by liquid scintillation counting. The total annual effective dose to the public was estimated from the measured activity concentrations and this was clearly below the International Commission on Radiological Protection (ICRP) reference level of 1 mSv y(-1) for pub...
Concentration of Potassium together with three other major essential elements in two medicinal pl... more Concentration of Potassium together with three other major essential elements in two medicinal plants used for the treatment of hypertension at the Center of Scientific Research into Plant Medicine (CSRPM), Mampong-Akuapem, Ghana, were determined by instrumental neutron activation analysis (INAA). The medicinal plants were Lippia multiflora and Bridelia ferruginea. Concentrations of Potassium (K) together with Magnesium (Mg), Chlorine (Cl) and Sodium (Na) were determined by short and medium irradiation at the Ghana Research Reactor-1 under an average neutron flux density of 5.0×10 11 ncm -2 s -1 . The elemental concentrations in mg/kg for each case of the medicinal plant samples varied as K > Mg > Cl > Na with Lippia multiflora the highest in each case except for Na as compared to Bridelia ferruginea. Na was found to be about 0.9% of K for Lippia multiflora and about 2.3% of K for Bridelia ferruginea. The variation in the concentration of these elements is due to factors su...
The average gross alpha and gross beta activities and the corresponding annual committed effectiv... more The average gross alpha and gross beta activities and the corresponding annual committed effective dose due to the major alpha and beta emitting radionuclides in the Uranium and Thorium series have been determine for nine different medicinal plants that are commonly used in Ghana using Canberra iMatic™ Automatic low background gas-less counter. Samples of the medicinal plants were obtained from the Centre for Scientific Research into Plant Medicine in Ghana and prepared using for different methods for analysis. The average gross alpha activity was found to be in the range of 11.73±0.61 Bq kg -1 to 132.67±7.22 Bq/kg in the raw sample of Lippia multiflora and the ethanol extraction sample of Alstonia boonei respectively. Likewise, the average gross beta activity was found to be in the range of 124.34±11.28 Bq/kg to 790.58±13.19 Bq/kg in the raw sample of Cassia sieberiana and the ethanol extraction sample of Nauclea latifolia. The average gross alpha activities were far less than the ...
Radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs in soil samples and water sources aro... more Radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs in soil samples and water sources around the Ghana Research Reactor-1 (GHARR-1) and the immediate surroundings have been measured using gamma spectrometry. The primary aim of the study was to establish baseline radioactivity levels in the environs of GHARR-1. The average activity concentration of 226Ra, 232Th, 40K and 137Cs were 22.3 ± 1.12 Bq kg-1, 49.8 ± 1.60 Bq kg-1, 99.60 ± 5.81 Bq kg-1 and 1.48 ± 0.25 Bq kg-1 for soil and 0.60 ± 0.11 Bq l-1, 2.13 ± 0.21 Bq l-1, 10.75 ± 0.84 Bq l-1 and 0.47 ± 0.05 Bq l-1for the water, respectively. The 226Ra and 232Th concentrations compare quite well with world averages, whilst the 40K concentration was lower than the world average. The levels of 137Cs observed in the samples are within the range of ‘background’ concentrations. The estimated average annual effective doses from external exposure to soil and ingestion of water samples were calculated to be 0.06 mSv and 0.53 mSv, respecti...
ABSTRACT Direct gamma spectrometry study was carried out within and around the operational area o... more ABSTRACT Direct gamma spectrometry study was carried out within and around the operational area of the Central Ashanti Gold of Ghana to ascertain the baseline radioactivity levels of naturally occurring radioactive materials (NORM), prior to processing of gold ore at the mine. The average activity concentrations of 238U, 232Th, 40K and 137Cs in the soil/rock samples were 64.3, 68.4, 1243.9 and 3.5 Bqkg−1, respectively. For the water samples, the average activity concentrations were 2.5, 2.6, 14.7 and 0.7 BqL−1 for 238U, 232Th, 40K and 137Cs, respectively. The total annual effective dose to the public was estimated to be 0.141 mSv which is below the ICRP recommended level of 1 mSv for public exposure control. The average radium equivalent activity value was 257.8 Bqkg−1 in the range of 72.9–402.3 Bqkg−1. The average values of external and internal indices were 0.7 and 0.8, respectively. The concentrations of U, Th and K were variable in soil and rock samples taken from different locations in the study area with values varying in the range of 0.8–10.9, 2.4–39.4 μg/g and 0.7–6.3 %, respectively. The concentration values of gross-α and gross-β for all the water samples were below the Ghana Standards Board and Who Health Organisation recommended guideline values for drinking water quality. The results obtained in this study shows that radiation levels are within the natural background radiation levels found in literature and compared well with similar studies for other countries.
This study was carried out to determine the sensitivity and specificity of serum CA 15-3 as a mar... more This study was carried out to determine the sensitivity and specificity of serum CA 15-3 as a marker in detecting and monitoring treatment in, breast cancer patients. One hundred and ten patients comprising 35 known breast cancer patients, 75 suspected cases and 20 controls entered the study. Blood samples were taken before and after treatment from the 35 known cases as well as the 75 suspected cases from which biopsy specimens were also taken. Serum CA 15-3 was measured by BioCheck CA 15-3 Enzyme Immunoassay. There was a significant difference between the concentration of serum CA 15-3 of the 35 known breast cancer patients before and after treatment (p < 0.05). Out of the 75 suspected cases, 46 had breast cancer and 29 had benign breast disease (histologically proven). There was a strong positive correlation between the level of serum CA 15-3 and the histopathology results of the biopsies (r = 0.518). The mean serum CA 15-3 concentration of the 46 patients (80.6 +/- 70.2 U mL(-1)) was significantly higher (p < 0.05) than that of the 29 patients with benign breast disease (12.0 +/- 9.0). The sensitivity and specificity of the serum CA 15-3 in detecting breast cancer was 76.1 and 100%, respectively at a cut-off of 35 U mL(-1). Serum CA 15-3 was found to have a value in the early detection and monitoring of treatment of breast cancer in Ghana.
Processing of crude oil has been carried out in Ghana for more than four decades without measures... more Processing of crude oil has been carried out in Ghana for more than four decades without measures to assess the hazards associated with the naturally occurring radionuclides in the raw and processed materials. This study investigates the exposure of the public to (226)Ra, (232)Th and (40)K in crude oil, petroleum products and wastes at the Tema oil refinery in Ghana using gamma-ray spectrometry. The study shows higher activity concentrations of the natural radionuclides in the wastes than the crude oil and the products with estimated hazard indices less than unity. The values obtained in the study are within recommended limits for public exposure indicating that radiation exposure from processing of the crude oil at the refinery does not pose any significant radiological hazard but may require monitoring to establish long-term effect on both public and workers.
Journal of Radioanalytical and Nuclear Chemistry, 2011
... These values are similar to that obtained for tailings samples by Boadu in 2001 [19] and for ... more ... These values are similar to that obtained for tailings samples by Boadu in 2001 [19] and for river sediments by Nyarko in 2003 [20] at other mining areas in Ghana. The similarity is due to the com-mon geological features (arsenopyrite) shared by the
Journal of Radioanalytical and Nuclear Chemistry, 2012
ABSTRACT Studies have been carried out on the distribution of major and trace elements concentrat... more ABSTRACT Studies have been carried out on the distribution of major and trace elements concentrations in oxide and sulphide feed ores at various stages of milling and processing of gold in a goldmine at Bogoso in the western region of Ghana. The studies evaluated concentration enhancements at various stages of treatment with emphasis on understanding the typical processes leading to enhancement of concentration at each stage and ultimately the impact from discharges into the surrounding environment. The feed ore samples were analyzed using energy dispersive X-ray fluorescence spectrometry. The results show concentration enhancements of a significant number of elements at some stages of processing in the two processing plants with the highest number of elements with enhanced concentrations coming from chemically treated media of both plants. Though there are relatively high concentrations of V (max.: 284 ppm), Cr (max.: 149 ppm), Co (max.: 84 ppm), and U (max.: 26.8 ppm) at the discharge points, the concentrations of most of the toxic elements in the slurries discharged into the tailings dam are mostly within their respective world averages. The enrichment indices computed for the slurries being discharged into the tailings dam suggests that the dam is not enriched with the toxic elements Cr, Co, Ni, Zn, Cu and Pb. The enrichment index of the slurries discharged into the tailings dam decreases in the order of oxide plant > sulphide plant. Principal component analyses performed suggest that Al2O3, K2O, Co, Zn, Cu, Y and Zr are geochemically associated. Results from the studies also suggest that the discharge of these elements into the tailings dam may contribute insignificant pollution of the surrounding area.
The possible environmental impacts of naturally occurring radionuclides on workers and a critical... more The possible environmental impacts of naturally occurring radionuclides on workers and a critical community, as a result of milling and processing sulfide ores for gold by a mining company at Bogoso in the western region of Ghana, have been investigated using gamma spectroscopy. Indicative doses for the workers during sulfide ore processing were calculated from the activity concentrations measured at both physical and chemical processing stages. The dose rate, annual effective dose equivalent, radium equivalent activity, external and internal hazard indices, and radioactivity level index for tailings, for the de-silted sediments of run-off from the vicinity of the tailings dam through the critical community, and for the soils of the critical community's basic schools were calculated and found to be lower than their respective permissible limits. The environmental impact of the radionuclides is therefore expected to be low in this mining environment.
The safety culture of selected practices and facilities in Ghana utilising radiation sources or r... more The safety culture of selected practices and facilities in Ghana utilising radiation sources or radiation emitting devices has been assessed using a performance indicator, which provided status information on management and operating staff commitment to safety. The questionnaire was based on the following broad areas: general safety considerations, safety policy at the facility level, safety practices at the facility level, definition of responsibility, staff training, safety of the physical structure of the facility and the emergency plans. The analysis showed that the percentage levels of commitment to safety for the respective practices are as follows: conventional radiography, 23.3-90.0%; research reactor, 73.3%; gamma irradiation facility, 53.3%; radiotherapy, 76.7%; X-ray scanner, 80.0%; gamma scanner, 76.7%; industrial radiography 86.7% and nuclear density practice, 78%. None of the practices or facilities was able to satisfy all the requirements that will ensure a 100% level of safety culture.
Journal of Radioanalytical and Nuclear Chemistry, 2015
ABSTRACT Dear Editor-in-Chief,We appreciate the letter written by Dr. M. U. Khandaker, drawing ou... more ABSTRACT Dear Editor-in-Chief,We appreciate the letter written by Dr. M. U. Khandaker, drawing our attention to some aspects in our publication he thought needed to be addressed. We however disagreed with most of the issues he raised and our responses are as follows:He thought the minimum detectable activity (MDA) value for K is too low, the counting time was too short based on his experience and why distilled water was used. First of all the distilled water was used to limit the level of backscatter radiation within the detector system during the background count. Also, we want to state that a low background spectrometry system was used for the counting. In other to optimize the result of the background count and the real samples, the same counting time was used. We agree that the longer the counting time the greater the peak area, however, based on the prevailing laboratory condition which could not enable us to consider a longer counting time 36,000 was used which could also give an apprec ...
Journal of Radioanalytical and Nuclear Chemistry, 2012
Abstract Knowledge of radioactivity levels in human diet is of particular concern for the estimat... more Abstract Knowledge of radioactivity levels in human diet is of particular concern for the estimation of possible radiological hazards to human health. However, very few surveys of radioactivity in food have been conducted in Ghana. The natural radionuclides 226 Ra, ...
ABSTRACT Studies were conducted in the vicinity of a gold processing plant at Tarkwa (Western Reg... more ABSTRACT Studies were conducted in the vicinity of a gold processing plant at Tarkwa (Western Region, Ghana) to obtain baseline radioactivity data prior to the installation of Cs-137 nuclear density gauges for quality control measure-ment of the density of slurry in the pipelines at the plant. A survey meter, gamma spectrometry and alpha-guard were used to obtain data on radionuclide concentrations in the environment, and determine the effective dose to workers. The results indicated the absence of any artificial radioactivity within the environs of the plant. The levels of Cs-137 before installing the gauges were within the detection limit of 1.5 Bq/kg. The effective doses estimated from the naturally occurring radionuclides were within the limits set by International Commission on Radiological Protection. Journal of Applied Science and Technology Vol. 12 (1&2) 2007: pp. 18-24
Journal of Radioanalytical and Nuclear Chemistry, 2014
ABSTRACT Direct gamma spectrometry study was carried out within lower basin of river Pra to ascer... more ABSTRACT Direct gamma spectrometry study was carried out within lower basin of river Pra to ascertain the baseline radioactivity levels of naturally occurring radioactive materials. The average activity concentrations of U-238, Th-232 and K-40 in the soil and sediment were 25.51, 28.04 and 238.98 Bqkg(-1) for soil, and 16.02, 20.31 and 27.39 Bqkg(-1) for the sediment. The study indicated that the activity concentrations of U-238, Th-232 and K-40 in the water were calculated to be 2.51, 1.71 and 41.43 BqL(-1), respectively and the corresponding annual effective dose ranged from 0.35 to 3.91 with an average of 1.82 mu Svyear(-1). These values are within the levels allowed elsewhere or recommended by the WHO.
Radioactivity concentration of Naturally Occurring Radioactive Materials (NORMs) in shore sedimen... more Radioactivity concentration of Naturally Occurring Radioactive Materials (NORMs) in shore sediments (samples) collected along the coast of Accra were analyzed using a gamma spectrometry with a high purity germanium detector. The specific activity concentrations range from 8.60 Bqkg -1 to 61.01 Bqkg -1 with a mean of 29.78 Bqkg -1 for 40 K, 0.62 Bqkg -1 to 148.80 Bqkg -1 with a mean of 22.04 Bqkg -1 for 226 Ra and 0.17 Bqkg -1 to 732.60 Bqkg -1 with a mean of 108.60 Bqkg -1 for 232 Th. The 40 K concentration compares well with the world average value while that for 226 Ra and 232 Th does not. The average absorbed dose rate was estimated to range from 0.75 nGyh -1 to 509.38 nGyh -1 with an average of 77.02 nGyh -1 , while the average annual effective dose also ranged from 0.00 mSvy -1 to 0.63 mSvy -1 with an average of 0.09 mSvy -1 was also estimated. The average radium equivalent activity and average external hazard index were also estimated to be 9.00 Bqkg -1 and 0.48 respectively a...
Radiometric determinations have been carried out to assess public exposure to radioactivity for c... more Radiometric determinations have been carried out to assess public exposure to radioactivity for communities along the coast of a shallow water offshore oilfield in Ghana (which started their operations recently) in order to establish baseline data using alpha spectrometry after radiochemical separation and non-destructive gamma spectrometry. The average activity concentrations of (234)U, (238)U, (230)Th and (232)Th by alpha-particle spectrometry and of (226)Ra, (228)Ra, (228)Th, (40)K, (210)Pb, (234)Th and (137)Cs by gamma-ray spectrometry were determined in the soil samples. The activity concentrations of (234)U, (238)U, (230)Th and (232)Th were determined in the water samples by alpha-particle spectrometry and of (226)Ra by liquid scintillation counting. The total annual effective dose to the public was estimated from the measured activity concentrations and this was clearly below the International Commission on Radiological Protection (ICRP) reference level of 1 mSv y(-1) for pub...
Concentration of Potassium together with three other major essential elements in two medicinal pl... more Concentration of Potassium together with three other major essential elements in two medicinal plants used for the treatment of hypertension at the Center of Scientific Research into Plant Medicine (CSRPM), Mampong-Akuapem, Ghana, were determined by instrumental neutron activation analysis (INAA). The medicinal plants were Lippia multiflora and Bridelia ferruginea. Concentrations of Potassium (K) together with Magnesium (Mg), Chlorine (Cl) and Sodium (Na) were determined by short and medium irradiation at the Ghana Research Reactor-1 under an average neutron flux density of 5.0×10 11 ncm -2 s -1 . The elemental concentrations in mg/kg for each case of the medicinal plant samples varied as K > Mg > Cl > Na with Lippia multiflora the highest in each case except for Na as compared to Bridelia ferruginea. Na was found to be about 0.9% of K for Lippia multiflora and about 2.3% of K for Bridelia ferruginea. The variation in the concentration of these elements is due to factors su...
The average gross alpha and gross beta activities and the corresponding annual committed effectiv... more The average gross alpha and gross beta activities and the corresponding annual committed effective dose due to the major alpha and beta emitting radionuclides in the Uranium and Thorium series have been determine for nine different medicinal plants that are commonly used in Ghana using Canberra iMatic™ Automatic low background gas-less counter. Samples of the medicinal plants were obtained from the Centre for Scientific Research into Plant Medicine in Ghana and prepared using for different methods for analysis. The average gross alpha activity was found to be in the range of 11.73±0.61 Bq kg -1 to 132.67±7.22 Bq/kg in the raw sample of Lippia multiflora and the ethanol extraction sample of Alstonia boonei respectively. Likewise, the average gross beta activity was found to be in the range of 124.34±11.28 Bq/kg to 790.58±13.19 Bq/kg in the raw sample of Cassia sieberiana and the ethanol extraction sample of Nauclea latifolia. The average gross alpha activities were far less than the ...
Radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs in soil samples and water sources aro... more Radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs in soil samples and water sources around the Ghana Research Reactor-1 (GHARR-1) and the immediate surroundings have been measured using gamma spectrometry. The primary aim of the study was to establish baseline radioactivity levels in the environs of GHARR-1. The average activity concentration of 226Ra, 232Th, 40K and 137Cs were 22.3 ± 1.12 Bq kg-1, 49.8 ± 1.60 Bq kg-1, 99.60 ± 5.81 Bq kg-1 and 1.48 ± 0.25 Bq kg-1 for soil and 0.60 ± 0.11 Bq l-1, 2.13 ± 0.21 Bq l-1, 10.75 ± 0.84 Bq l-1 and 0.47 ± 0.05 Bq l-1for the water, respectively. The 226Ra and 232Th concentrations compare quite well with world averages, whilst the 40K concentration was lower than the world average. The levels of 137Cs observed in the samples are within the range of ‘background’ concentrations. The estimated average annual effective doses from external exposure to soil and ingestion of water samples were calculated to be 0.06 mSv and 0.53 mSv, respecti...
ABSTRACT Direct gamma spectrometry study was carried out within and around the operational area o... more ABSTRACT Direct gamma spectrometry study was carried out within and around the operational area of the Central Ashanti Gold of Ghana to ascertain the baseline radioactivity levels of naturally occurring radioactive materials (NORM), prior to processing of gold ore at the mine. The average activity concentrations of 238U, 232Th, 40K and 137Cs in the soil/rock samples were 64.3, 68.4, 1243.9 and 3.5 Bqkg−1, respectively. For the water samples, the average activity concentrations were 2.5, 2.6, 14.7 and 0.7 BqL−1 for 238U, 232Th, 40K and 137Cs, respectively. The total annual effective dose to the public was estimated to be 0.141 mSv which is below the ICRP recommended level of 1 mSv for public exposure control. The average radium equivalent activity value was 257.8 Bqkg−1 in the range of 72.9–402.3 Bqkg−1. The average values of external and internal indices were 0.7 and 0.8, respectively. The concentrations of U, Th and K were variable in soil and rock samples taken from different locations in the study area with values varying in the range of 0.8–10.9, 2.4–39.4 μg/g and 0.7–6.3 %, respectively. The concentration values of gross-α and gross-β for all the water samples were below the Ghana Standards Board and Who Health Organisation recommended guideline values for drinking water quality. The results obtained in this study shows that radiation levels are within the natural background radiation levels found in literature and compared well with similar studies for other countries.
This study was carried out to determine the sensitivity and specificity of serum CA 15-3 as a mar... more This study was carried out to determine the sensitivity and specificity of serum CA 15-3 as a marker in detecting and monitoring treatment in, breast cancer patients. One hundred and ten patients comprising 35 known breast cancer patients, 75 suspected cases and 20 controls entered the study. Blood samples were taken before and after treatment from the 35 known cases as well as the 75 suspected cases from which biopsy specimens were also taken. Serum CA 15-3 was measured by BioCheck CA 15-3 Enzyme Immunoassay. There was a significant difference between the concentration of serum CA 15-3 of the 35 known breast cancer patients before and after treatment (p < 0.05). Out of the 75 suspected cases, 46 had breast cancer and 29 had benign breast disease (histologically proven). There was a strong positive correlation between the level of serum CA 15-3 and the histopathology results of the biopsies (r = 0.518). The mean serum CA 15-3 concentration of the 46 patients (80.6 +/- 70.2 U mL(-1)) was significantly higher (p < 0.05) than that of the 29 patients with benign breast disease (12.0 +/- 9.0). The sensitivity and specificity of the serum CA 15-3 in detecting breast cancer was 76.1 and 100%, respectively at a cut-off of 35 U mL(-1). Serum CA 15-3 was found to have a value in the early detection and monitoring of treatment of breast cancer in Ghana.
Processing of crude oil has been carried out in Ghana for more than four decades without measures... more Processing of crude oil has been carried out in Ghana for more than four decades without measures to assess the hazards associated with the naturally occurring radionuclides in the raw and processed materials. This study investigates the exposure of the public to (226)Ra, (232)Th and (40)K in crude oil, petroleum products and wastes at the Tema oil refinery in Ghana using gamma-ray spectrometry. The study shows higher activity concentrations of the natural radionuclides in the wastes than the crude oil and the products with estimated hazard indices less than unity. The values obtained in the study are within recommended limits for public exposure indicating that radiation exposure from processing of the crude oil at the refinery does not pose any significant radiological hazard but may require monitoring to establish long-term effect on both public and workers.
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