Browsing by Author "Adu-Kumi, S."
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Item Contaminated Site Investigation using Nuclear Technique: A Case Study of Temporary Transformer Storage Sites in Ghana(University of Ghana, 2013-07) Senu, J.K.; Fianko, J.R.; Adu-Kumi, S.; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Sciences and ApplicationsRecent introduction of man-made toxic chemicals, and the massive relocation of natural materials to different environmental compartments like soil, ground water and atmosphere, has resulted in severe pressure on the self-cleansing capacity of recipient ecosystems. Various accumulated pollutants and contaminants such as polychlorinated biphenyls (PCBs) are of much concern relative to both human and ecosystem exposure and potential health impact. PCBs which are resistant to degradation and bioremediation accumulate in different niches of the biosphere. This significantly affects ecological balance and cause adverse health effect on both human and the environment. Temporal transformer storage sites at four locations in Ghana (Tema, Tamale, Bolgatanga and Wa) were investigated for PCB contamination using nuclear techniques. Analysis of soil samples from four temporal transformer storage sites revealed that the soil samples from Tema, Tamale, Bolgatanga and Wa were generally sandy with pH and EC ranging between 6.24 - 7.29 and 44.60 – 188.30 respectively. The PCB levels detected in the soil samples from the various locations varied considerably with mean ranging between 7.69 and 51.92 mg/Kg. The highest mean PCB level was recorded at the Tema temporal transformer storage site (51.92 mg/Kg), while the least mean level of 7.69 mg/Kg was recorded at Wa storage site. At Tamale the individual levels ranged between 3.57 mg/Kg and 38.70 mg/Kg while at Bolgatanga it was 6.85 – 16.30 mg/Kg and Wa, 6.08 – 14.70 mg/Kg. About 9% of soil samples from temporal transformer storage sites analysed had total PCBs concentrations above the 25 mg/Kg and 33 mg/Kg level recommended by the Canadian Council of Ministers of environment (CCME) and EPA Ghana respectively for the protection of environment and human health. Generally, the levels of PCBs in soil samples were found to decrease with increasing depth at all the temporal transformer storage sites. Results obtained using the EPA’s L2000DX PCB/ Chloride Analyser and Instrumental Neutron Activation Analysis (INAA) to analyse extractable organochlorine from the soil samples indicated that the nuclear technique is a better analytical technique for contaminated site investigation due to its high sensitivity, selectivity, fast and non-destructive nature. The INAA and gamma spectroscopy using HPGe detector coupled with MAESTRO 32 software provided a fast and efficient way to analyse possible PCB contamination in the soil samples and therefore proved to be very reliable method that could be conveniently used for contaminated site investigationItem Levels and seasonal variations of organochlorine pesticides in urban and rural background air of southern Ghana(Environmental Science and Pollution Research, 2012-06) Adu-Kumi, S.; Kareš, R.; Literák, J.; Borůvková, J.; Yeboah, P.O.; Carboo, D.; Akoto, O.; Darko, G.; Osae, S.; Klánová, J.Urban, suburban and rural background air samples were collected in southern Ghana in 2008 employing polyurethane foam disc passive air samplers (PAS). PAS were analysed for organochlorine pesticides (OCPs), namely hexachlorocyclohexanes (α-, β-, γ- and δ-hexachlorocyclohexane), dichlorodiphenyltrichloroethane including metabolites (o,p′- and p,p′-DDT, DDE and DDD), hexachlorobenzene, pentachlorobenzene, aldrin, dieldrin, endrins (endrin, endrin aldehyde and endrin ketone), isodrin, heptachlors (heptachlor, heptachlor epoxide A and heptachlor epoxide B), chlordanes (α-, β-chlordane, oxychlordane and trans-nonachlor), endosulfans (α- and β-endosulfan and endosulfan sulphate), methoxychlor and mirex using a gas chromatograph coupled to a mass spectrometer. The levels of OCPs ranged for the individual pesticides from below limit of quantification to 750 pg m-3 (for α-endosulfan), and current agricultural application seemed to be the main primary source of most abundant pesticides. Re-volatilization of previously used pesticides from contaminated soils could not be ruled out either as potential secondary source of contamination, especially in warm and dry seasons and periods of intensive agricultural activities. Higher atmospheric concentrations were observed in November and December during the dry season compared to lower concentrations observed in June, July and August when the country experiences heavy rains. The highest seasonal variation was observed for currently used pesticides as α-endosulfan. A p,p′-DDT/p,p′-DDE ratio suggested recent inputs of fresh technical DDT. © 2012 Springer-Verlag.Item A novel D:A-friedooleanane triterpenoid and other constituents of the stem bark of Dichapetalum barteri Engl.(Arkivoc, 2007-01) Addae-Mensah, I.; Adu-Kumi, S.; Waibel, R.; Oppong, I.V.A novel pentacyclic triterpenoid, 2β-hydroxy-3-oxo-D:A-friedoolenanan- 29-oic acid has been isolated from the methanol extract of the stem bark of Dichapetalum barteri, and characterised by spectroscopic methods. Also reported for the first time from the plant are two lupane-type triterpenoids betulinic acid and betulonic acid, the friedelane triterpenoids syn:canophyllal, syn:canophyllol, friedelan-3-one and friedelan-3α-ol (epifriedelinol), the more common triterpenoids β-sitosterol and stigmasterol, as well as seven long chain esters of ferulic acid. ©ARKAT USA, Inc.Item Organochlorine pesticides (OCPs), dioxin-like polychlorinated biphenyls (dl-PCBs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo furans (PCDD/Fs) in edible fish from Lake Volta, Lake Bosumtwi and Weija Lake in Ghana(Chemosphere, 2010-10) Adu-Kumi, S.; Kawano, M.; Shiki, Y.; Yeboah, P.O.; Carboo, D.; Pwamang, J.; Morita, M.; Suzuki, N.Organochlorine pesticides (OCPs), dioxin-like polychlorinated biphenyls (dl-PCBs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo furans (PCDD/Fs) were measured by a high resolution gas chromatograph-high resolution mass spectrometer (HRGC/HRMS) in selected edible fish from three freshwater bodies, Lake Volta, Lake Bosumtwi and Weija Lake in Ghana. The levels of organochlorine pesticides measured in this study were generally low. The highest concentration of OCPs was measured for dichlorodiphenyltrichloroethane compounds (DDTs) (p,. p′-DDT, o,. p′-DDT, p,. p′-DDE, o,. p′-DDE, p,. p′-DDD and o,. p′-DDD), followed by chlordane compounds (CHLs) (trans-chlordane, cis-chlordane, trans-nonachlor and cis-nonachlor), hexachlorobenzene (HCB) and gamma-hexachlorocyclohexane (γ-HCH). The relatively high ratio of p,. p′-DDT/. p,. p′-DDE in tilapia and catfish with an extremely high value in catfish purchased from a local market at Madina, a suburb of Accra, however, suggests the fresh contamination of technical DDT in Ghana. Although PCDD/Fs and dl-PCBs showed relatively low levels, the concentrations are, however, comparable with recent data of some developed countries. There is a potential health risk from DDTs, PCDD/Fs and dl-PCBs for the general population of Ghana because fish is one of their important protein sources. It is therefore necessary to estimate the total intake of DDTs, PCDD/Fs and dl-PCBs, and to assess the health risks for the general population of Ghana. © 2010 Elsevier Ltd.