Multielemental Analysis of Migori (Southwest, Kenya) Artisanal Gold Mine Ores and Sediments by EDX-ray Fluorescence Technique: Implications of Occupational Exposure and Environmental Impact

摘要

The results of heavy element profiling of the gold ores and sediments associated with the artisanal gold mining activities of the Migori gold belt of Southwestern Nyanza, Kenya, were reported in this paper. The analysis was made to assess the occupational exposure of the miners as well as to investigate the environmental impact of toxic heavy metals. Gold ores and sediments from the artisanal gold processing were sampled in four artisanal gold mining areas: Osiri A, Osiri B, Mikei and Macalder (Makalda) and analyzed for heavy elemental content using 109Cd radioisotope excited EDXRF spectrometry technique. Analysis consisted of direct irradiating of sample pellets. The concentrations of major elements detected were: titanium (711.41–10,766.67 mg/kg); cobalt (82.65–1,010.00 mg/kg); zinc (29.90–63,210 mg/kg); arsenic (29.30–8,246.59 mg/kg); gold (14.07–73.48 mg/kg); lead (16.31–14,999.40 mg/kg) and mercury (16.10–149.93 mg/kg). The average concentration of the heavy toxic metals i.e. arsenic, lead, titanium and zinc were found to be above 50 mg/Kg as recommended by World Health Organization.