Ekosse G.-I.E.,Directorate of Research Development |
Ngole V.M.,Walter Sisulu University
10th International Multidisciplinary Scientific Geoconference and EXPO - Modern Management of Mine Producing, Geology and Environmental Protection, SGEM 2010 | Year: 2010
Nickel-copper (Ni-Cu) mining and smelting activities within Selebi Phikwe area, Botswana is suspected to be having negative impact on the biophysical environment; thereby influencing the health of residents of this growing urbanised settlement. This paper focuses on relating the biophysical environmental hazards emanating from mining activities to human health status of residents of the study area. Mineralogical analysis of samples of tailings dump, soils, and particulate air matter (PAM) were conducted. Concentrations of heavy metals including Cd, Co, Cr, Cu, Fe, Ni, Se and Zn, in samples of tailings dump, soils, PAM, Colophospermum mopane (mopane plant), and Imbrasia belina (phane caterpillar) were also investigated using appropriate analytical tools. Xray diffraction analyses revealed nickelbloedite, Na2(Ni(SO4)2.4H2O; pyrrhotite; quartz, SiO2; pentlandite; malachite,Cu2CO3(OH)2; chalcopyrite; actinolite, Ca2(Mg,Fe)5Si8O22(OH)2; cristobalite; tremolite; kaolinite, Al2Si2O5(OH)4; mica and albite phases in the tailings dump. Mineralogy of whole soils consisted of actinolite, albite, quartz, microcline, KAlSi3O8; pyrrhotite, silicon sulphide, SiS; and cobalt oxide, CoO; whereas the < 2 μm soil fraction was made of kaolinite, smectite, Na0.3(Al,Mg)2Si4O10(OH)2.xH2O; anorthite, CaAl2Si2O8; illite, KAl2(Si3AlO10)(OH)2 and quartz. The PAM consisted of quartz, SiO2; pyrrhotite; chalcopyrite, CuFeS2; albite, and djurleite, Cu31S16. Concentrations of heavy metals measured in the different environmental media were associated with the identified minerals. High concentrations of heavy metals recorded in the different environmental media had affected the biophysical environmental quality at Selebi Phikwe. Findings of the study suggest that the heavy metals uptaken by Colophospermum mopane are translocated to Imbrasia belina mainly through ingestion. Contaminated Imbrasia belina are consumed by residents; thus posing as human health hazard. Pulmonary, respiratory and gastronomic sicknesses and diseases are rampant at the study area, and have been associated to the mining activities there. © SGEM2010 All Rights Reserved by the International Multidisciplinary Scientific GeoConference SGEM Published by STEF92 Technology Ltd.