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Item Human Health Risk Assessment of Exposure to Heavy Metals in Selected Mining Communities in Ghana.(University Of Ghana, 2018-01) Obiri, S.Gold mining is an important economic activity in Ghana. However, processing and extraction of gold from its ores generate a lot of wastes. Studies conducted in different countries have established that long-term exposure to As, Cd, Pb and Hg in the wastes could cause cancer and other non-cancerous diseases such as cardiovascular diseases. It is within this context that, this thesis assessed cancer and non-cancer human health risk associated with exposure to As, Cd, Hg and Pb in water and sediment via oral and dermal contact by receptors such as adults workers in mining companies or artisanal small-scale mines (ASM), resident adults (i.e., who do not work in either mining companies or ASM) and resident children in selected mining communities in Ghana. The study further evaluated the health risk associated with ingestion of food crops such as cassava grown in soils the study areas as well as the determination of levels of As, Cd, Pb and Hg in human such as whole blood and serum among resident adults (non-mine workers i.e., workers of mining companies or ASM), and resident children in selected mining and non-mining communities in Ghana in line with USEPA risk assessment guidelines as there exist limited information on this subject in Ghana. The study protocol was approved by the Ghana Health Service Ethical Review Committee. Random sampling techniques were adopted in selecting the sampling sites as well as recruitment of respondents who donated their blood samples as well as provided information about their personal health in relation to cardiovascular diseases. The collected water, sediment and cassava samples were stored under 4ºC and conveyed to the CSIR-Water Research Institute laboratory for analysis. The blood samples were collected by laboratory staff of Tarkwa Nsuaem Municipal Hospital, Cape Coast metropolitan Hospital, Health Centre at Bole and Nangodi respectively. The blood samples were separated into whole blood and serum by the laboratory staff and conveyed to Ghana Atomic Energy Commission for analysis of As, Cd and Hg using the NAA at Ghana Reactor 3 under -4ºC; while the Pb levels in the blood samples were determined using GFAAS at Heavy Metals Laboratory of CSIR-Water Research Institute. The mean concentrations for As, Hg, Cd and Pb in whole blood of resident adults from mining communities in Tarkwa Nsuaem Municipality were; 38 ± 0.20 μgL-1, 63 ± 0.23 μgL-1, 303 ± 117 μgL-1 and 28 ± 14 μgL-1 respectively; while the levels of As, Hg, Cd and Pb measured in serum of resident adults from mining communities were; 65 ± 14 μgL-1, 358 ±22 μgL-1, 134 ± 12 μg/L, 58 ±5.8 μgL-1 respectively for As, Hg, Cd and Pb. These were found to have exceeded the permissible WHO guideline values. The mean concentrations of As, Cd, Hg and Pb in water samples ranged from 15 μg/L to 325 μg/L (As), 0.17 μg/L to 340 μg/L (Cd), 0.17 μg/L to 122 μg/L (Pb) and 132 μg/L to 866 μg/L (Hg) respectively. These measured concentrations of arsenic (As), mercury (Hg), cadmium (Cd) and lead (Pb) were used as input parameters to calculate the cancer and non–cancer health risks from exposure to these metals in surface water bodies and sediments based on an occupational exposure scenario using Central Tendency Exposure (CTE) and Reasonable Maximum Exposure (RME) parameters. The results of the non-cancer human health risk assessment for small-scale miners working around river Anikoko were expressed in terms of hazard quotients based on CTE parameters are as follows: 0.04 (Cd), 1.45 (Pb), 4.60 (Hg) and 1.98 (As); while cancer health risk faced by ASGM miners in Dumase exposed to As in River Mansi via oral ingestion of water is 3.1 × 10−3. The hazard quotient results obtained from this study in most cases were above the HQ guidance value of 1.0. Furthermore the cancer health risk results were found to be higher than the USEPA guidance value of 1 × 10−4 to 1 × 10−6. The findings from case-control epidemiological studies established a strong relationship between exposure to As in drinking water and incidence of cardiovascular diseases among residents in the study areas. The results from this study calls for strong policy interventions to address the issue of health and safety of both mine workers and residents of mining communities in Ghana.Item Characterization of Atmospheric Particulate Matter at E-Waste Landfill Site in Agbogbloshie, Accra(University of Ghana, 2017-07) Ahiamadjie, H.A year-long investigation has been carried out on atmospheric particulate matter (APM). Elemental composition,mass concentration, sources contributions and their ngerprints were determined in APM samples collected, in Agbogbloshie scrap market, between May 2010 and April 2011. PM2:5 and PM102:5 size fractions of APM were collected 24-hourly on 47 mm diameter nuclepore lters of pore sizes 0.4 μm and 8 μm respectively, using the Gent sampler. Gravimetric analyses were carried out to determine the APM mass concentrations. The minimum, maximum and annual mean mass concentration values for PM2:5 obtained for the sampling site throughout the period of investigation were 35.43 ( g=cm3), 349.68 ( g=cm3) and 88.62 ( g=cm3) respectively. For PM10��2:5, the minimum, maximum and annual mean mass concentration values obtained were 76.83( g=cm3), 448.67 ( g=cm3) and 138.31 ( g=cm3) respectively. These measured concentration levels are all substantially higher than the WHO, USEPA, EU, JAPAN EQS, UK National Air quality objective, World Bank and Canada air quality standards. Particle Induced X-Ray Emmission (PIXE), Particle Induced Gamma Emmission (PIGE) and Energy Dispersive X-Ray Fluorescence (EDXRF) were used to determine elemental composition and concentration of the atmospheric particulate matter. The ve most abundant elements in coarse fraction PM102:5 are Si average 6545.05 (range: 261.3359950.56) ngm��3, Al average 3743.25 (range: 218.9424719.25) ngm��3, Fe average 2464.77 (range: 182.0818982.45) ngm��3 , Cl average 5918.47 (range: 587.76 15796.13) ngm��3, Na average 4040.17, (range: 418.2515010.32) ngm��3. In the ne fraction (PM2:5) concentrations reordered were in the following order: Si average 5466.44 (range: 1339.9361029.16) ngm��3 , Al average 3073.44 (range: 888.7425389.05) ngm��3, Fe average 1877.57 ( range : 769.2819569.65) ngm��3, Cl average 4972.86 (range: 1533.3616741.73) ngm��3, Na average 3163.27 (range: 1295.1515887.22) ngm��3. Enrichment Factor evaluation was rst used as one of the means to separate elements in terms of natural and anthropogenic sources. PMF was employed in ngerprint and source contributions identi cations, PMF resolved ve sources each for both PM2:5 and PM10��25. The following sources were identi ed for the PM2:5:E-waste burning (49%), Industrial activities (23%), vehicular tra c (16%), resuspended dust (7%) and sea spray (5%). In the coarse fraction, soil dust (45%),biomass burning (17%), Heavy oil burning (16%),sea spray (12%) and e-waste burning (10%) were apportioned. Natural sources (45%) were the major contributors in the coarse fraction while anthropogenic sources(88%) were the major contributors in the ne fraction. E-waste burning contributions were identied in both fractions. In this work, the following elements (Zn, As, Br, Sn, Cd, Hg, Pb) have been identi ed as ngerprint for e-waste burning and this source contributed 49% of the pollutants identied in the study area.Item Numerical Simulation of Dispersion of Emissions from Tema Oil Refinery in Ghana(University of Ghana, 2015-07) Afum, H.A.The petrochemical industry is a major contributor of industrial air pollutants which are known to have dire consequences on human health and the environment, neccesitating research into their dispersion and transport. The objective of the study, therefore, is to simulate the dispersion and transport of pollutants emitted during the processing of crude oil by the Tema Oil Refinery in the Greater Accra region of Ghana using the California Puff (CALPUFF) modeling system. This thesis couples the Weather Research and forecasting Model (WRF) with the non-steady state California Puff(CALPUFF) modelling system to simulate the dispersion and transport of emissions from the refinery in a coastal urban/industrial area in Ghana. The mass balance approach was employed to estimate the refinery emission rates which were used as input for the dispersion model. Emission rates of five species were estimated - SO2, NO2, PM2:5, CO2 and VOCs. The transport and dispersion of SO2, NO2 and PM2:5 were modelled over the period between 2008 - 2013 and their impact on 38 identifed receptors investigated. Simulation results showed that the radius of impact of the emissions is approximately 10 km. As a result of the prevailing predominant south-westerly winds in the study area, concentrations of emissions at receptors located upwind of the emission source were found to be higher as the winds carried the pollutant clouds in their direction. Conversely, south and south-western receptors, relative to the refinery, on the other hand, were minimally impacted. Concentrations of SO2 and NO2 at 2 out of the 38 receptors exceeded the regulatory limit of the World Health Organisation and Ghana's Environmental Protection Agency. It can be concluded, therefore, that SO2 and NO2 emissions from the refinery do not pose any danger to the larger population and the general environment nearby. PM2:5 levels at 36 receptors however exceeded the WHO guideline value leading to the conclusion that the refinery operations could pose some dangers to the environment regarding PM2:5. The dispersion model results were compared with measurements at the same location in order to validate the model. Similarly, observations from two meteorological stations were compared with results from the meteorological model. The performance evaluation, with the aid of statistical measures revealed that the models' performance were acceptable.Item Atmospheric Pollution Assessment from a Mountainous Environment in Southern Ghana: Case Study of Abetifi(University of Ghana, 2016-07) Palm, L.M.NIn the pursuit to improve man’s livelihood, human activities which include emission of heavy metals from various industries and sectors, as well as the past use of chemicals such as pesticides, polychlorinated biphenyls and flame retardants have often mobilized and redistributed natural substances and anthropogenic pollutants into the atmosphere, predisposing it to relatively high concentrations of such pollutants even in pristine areas in the environment. This study assessed the level of atmospheric pollution, contributing sources and human health exposure risk of persistent organic pollutants (POPs) along with selected heavy metals with focus on Abetifi, one of the highest altitude environments in Ghana. Passive sampling with polyurethane foam (PUF) as adsorbent was employed. Samplers were deployed every 84 days for two years. A total of 65 polyurethane foams were deployed and twelve (12) groups of analytes were considered together with their various isomers. High resolution gas chromatographic technique coupled with high resolution mass spectrometry (HRGC-HRMS) and electron capture detectors (ECD) were used in the analysis of the POPs. Besides, high performance liquid chromatography (HPLC) coupled with MS was employed in analysing the perfluorinated compounds (PFCs) while the heavy metals were analysed using Atomic Absorption Spectrometer (AAS). Principal Component Analysis (PCA) and UNMIX model were used to group pollution source contribution of all analytes (POPs and heavy metals) in this study. Diagnostic isomer and other predictive ratios were also employed for source apportionment of various individual analyte groups. Results revealed that polychlorinated dibenzo-furans gave with the least total mean concentration (0.074 pg/m3) for the sampling period and polybrominated biphenyls gave the highest (55 pg/m3). The pesticide group gave values in the order of DRINs (53 pg/m3) > DDT (41 pg/m3) > HCHs (28 pg/m3). Data for perflourinated compounds (PFCs) in the atmosphere at Abetifi was recorded with a maximum total concentration (Σ8) of 15 pg/m3. The human exposure level to dioxin-like chemicals in the air at the study location was 0.0067 pg TEQ/kg bw per day. The atmospheric pollution source observed at Abetifi was a mixed one consisting of agricultural, vehicular and from burning of biomass. Agricultural source was basically as a result of re-volatilization from polluted sinks (a secondary pollution source).Item Numerical Simulation of Dispersion of Emissions from Tema Oil Refinery in Ghana(University of Ghana, 2015) Affum, H. A.; Akaho, E. H. K.; Niemela, J. J.; Armenio, V.; Danso, K. A.; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Sciences and ApplicationsThe petrochemical industry is a major contributor of industrial air pollutants which are known to have dire consequences on human health and the environment, neccesitating research into their dispersion and transport. The objective of the study, therefore, is to simulate the dispersion and transport of pollutants emitted during the processing of crude oil by the Tema Oil Refinery in the Greater Accra region of Ghana using the California Pu_ (CALPUFF) modeling system. This thesis couples the Weather Research and forecasting Model (WRF) with the non-steady state California Pu_(CALPUFF) modelling system to simulate the dispersion and transport of emissions from the refinery in a coastal urban/industrial area in Ghana. The mass balance approah was employed to estimate the refinery emission rates which were used as input for the dispersion model. Emission rates of _ve species were estimated - SO2, NO2, PM2:5, CO2 and VOCs. The transport and dispersion of SO2, NO2 and PM2:5 were modelled over the period between 008 - 2013 and their impact on 38 identified receptors investigated. Simulation results showed that the radius of impact of the emissions is approximately 10 km. As a result of the prevailing predominant south-westerly winds in the study area, concentrations of emissions at receptors located upwind of the emission source were found to be higher as the winds carried the pollutant clouds in their direction. Conversely, south and south-western receptors, relative to the refinery, on the other hand were minimally impacted. Concentrations of SO2 and NO2 at 2 out of the 38 receptors exceeded the regulatory limit of the World Health Organisation and Ghana's Environmental Protection Agency. It can be concluded, therefore, that SO2 and NO2 emissions from the refinery do not pose any danger to the larger population and the general environment nearby. PM2:5 levels at 36 receptors however exceeded the WHO guideline value leading to the conclusion that the refinery operations could pose some dangers to the environment regarding PM2:5. The dispersion model results were compared with measurements at the same location in order to validate the model. Similarly, observations from two meteorological stations were compared with results from the meteorological model. The performance evaluation, with the aid of statistical measures revealed that the models' performance were acceptable.Item Hydrogeochemical Characterization of the Rocks of the Accra Plains for a Radioactive Waste Repository(University of Ghana, 2013-06) Glover, E.T; Akiti, T.T; Osae, S.D; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Sciences and ApplicationsThe geological disposal of radioactive waste in well-engineered repositories in stable geological formations has been internationally accepted as a suitable option. The disposal system makes use of both man-made and natural barriers to contain and isolation the radionuclides. Precambrian crystalline rocks are regarded as one of the favourable host rocks for a radioactive waste repository. Hydrogeochemical characterization of the rocks of the Accra Plains, located in the south eastern part of Ghana underlain by crystalline gneisses and schists, has been carried out to determine its suitability for a radioactive waste repository. The mineralogical analyses of the rock and soil samples collected indicated that feldspars, hornblende, biotite, quartz with minor pyroxenes are the primary minerals with illite, kaolinite, montmorillonite and carbonates occurring as secondary minerals. The accessory minerals present include chlorite, epidote, magnetite, rutile and sphene. The iron rich minerals, magnetite, biotite, chlorite, and amphiboles will create a reducing environment required for a repository. The pH value of the groundwater at the Valley View University is lower than the recommended pH values (6-10) for a repository environment, making the site unsuitable for a radioactive waste repository. Calcium and magnesium ions which constitute 48% of the total cations in the groundwater will provide a stable chemical environment for a backfill and buffer materials. The groundwaters of the Accra Plains is composed of three (3) water types. Groundwater Type 1 is composed of Na-Mg-Ca-Cl-HCO3 and found along the foot of the Akwapim-Togo Mountains. Groundwater Type 2 is composed of Na-Mg-Ca-Cl and found in most parts of the central area of the Plains whilst groundwater type 3 occur along the coastal zone of the Plains and composed of Na-Ca-Cl. Silicate mineral weathering is the predominant influence on the composition of the groundwaters. Evaporative enrichment of recharging waters, ion exchange and reverse ion exchange also controls the chemical composition of the groundwater especially along the coastal areas of the Plain. The stability diagram shows that the chemistry of the groundwater favours the formation of kaolinite and montmorillonite. The long time stability of these minerals together with their ion exchange properties which can retard the migration of long-lived radionuclides makes them a useful backfill and or buffer material for a radioactive waste repository. The groundwater had an average isotopic value of –3.19‰ for δ18O and –14.36‰ for δ2H. The groundwaters at Valley View University are more depleted than the other groundwaters in the Plains suggesting that the groundwater was recharge at a high elevation. The Akwapim-Togo Mountains would be the source of these groundwaters, implying there are preferential channels or routes through which waters that are recharged on the Akwapim-Togo Mountains find their way to the university campus. This makes that area unsuitable for a waste repository. The activity concentration of 40K was found to be higher than the other naturally occurring radionuclides which can be attributed to the abundance of K-feldspar minerals in the geological formation. The highest radionuclide concentrations were measured in the rock samples collected from GAEC premises whereas the Krobo Mountains samples had the lowest radionuclide concentrations. The relative U enrichment in the GAEC samples suggests reducing condition and precipitation of UO2. The Ashiaman samples reflected high Th concentration indicating preferential removal of uranium by leaching through groundwater infiltration. The area between the Akwapim Togo and the Valley View University was found to be unsuitable for a radioactive waste repository due to preferential channels which will easily saturate the repository. Secondly the pH of the groundwaters were lower than the required pH conditions for a radioactive waste repository The presence of redox-sensitive minerals in the mafic gneisses which will ensure a reducing environment for a radioactive repository makes the hydrogeochemical conditions of the geological formation at Okwenya and the foothills of the Krobo Mountains are favourable for a repository. The presence of montmorillonite clay minerals in these areas will give the repository with a good buffer material which will be stable for a long period of time and also retard the migration of the long live radionuclides.