| dc.description.abstract | Past copper mining activities in Kilembe led to piles of mine tailings in the catchment which are potential sources of trace metal contamination to the environment. This study was done to: (a) assess trace element concentrations in house dust, Amaranthus vegetables and drinking water supplies and incidences of mine related health complications among households (b) investigate the limitations of mine waste management processes in Kilembe mine area. The study employed both quantitative and qualitative data collection techniques. Following standard protocols, samples of Amaranthus, drinking water and house dust were collected from Kilembe area and control sites located 10 kilometers away from the mine contamination, prepared and analysed using the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Analysis of samples revealed that mean concentrations of cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As) and cadmium (Cd) in house dust; cobalt (Co), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb) in Amaranthus; and aluminium (Al), iron (Fe) and cobalt (Co) in drinking water sources from Kilembe mine area were significantly higher than controls. In dust, about 26% of samples exceeded 22 mgkg-1 cobalt (Co) residential threshold, 5% exceeded 1100 mgkg-1 copper (Cu) threshold while 2% exceeded 140 mgkg-1 lead (Pb) threshold. In Amaranthus vegetables, 39% of samples exceeded 0.3 mgkg-1 lead (Pb) threshold, 15 % exceeded 20 mgkg-1 copper (Cu) threshold, 64% exceeded 99.4 mgkg-1 zinc (Zn) threshold while 90% exceeded 0.05 mgkg-1 cadmium (Cd) threshold for human consumption. In drinking water, 3% of samples exceeded 200 µgL-1 aluminium (Al) threshold, 35% exceeded 200 µgL-1 iron (Fe) threshold while 9% exceeded 40 µgL-1 cobalt (Co) threshold for drinking water. Presence of high concentrations of trace elements in house dust, locally grown Amaranthus vegetables and water supplies in Kilembe mine area appeared to negatively affect the health of the residents. Indeed, a survey conducted revealed that ulcers, cancer, respiratory and gastrointestinal diseases were affecting many residents. These diseases could be associated with exposure to the toxic trace elements found in Kilembe house dust, Amaranthus vegetables and domestic water supplies. Women were more affected by the diseases associated with mine waste exposures than the men perhaps because they spent more time working in contaminated soils. Sensitization of local populations on mine waste exposure dangers is recommended. The tailings scattered in Kilembe mine area could also be processed further to extract commercially viable minerals left behind after copper extraction. An extensive epidemiological survey is recommended involving more households to enable adequate profiling of exposures and associated health risks. Key words: Tailings, population exposure, contamination, trace elements, risks, environment. | en_US |
