Health and Environmental Risk Assessment at Gold Panning Sites in the Northern Region (Burkina Faso)

Abstract

Gold panning has an important contribution in the economic development of Burkina Faso. However, the mining activities expose people and the environment to severe risks. The present study was initiated to estimate the impact of gold panning on health and environmental resources. Samples of sweet pepper, water and soils were taken for mercury and cyanide content analysis. Mercury was extracted from the matrices by aqua regia and analysed by atomic absorption spectrophotometry. The cyanides were extracted from the matrices by centrifugation and analysed by colorimetry. Analyses showed the presence of mercury in soil samples but with contents lower than the standard of culture setting soils (5 mg/kg) except one, which displayed a mercury content of 13.45 mg/kg. In the same way, sweet pepper sample contained 3.17 mg/kg of mercury. Soils samples taken in the agricultural field were strongly contaminated by mercury and presented a very high potential ecological risk. In surface water and groundwater, the results of mercury analysis were all lower than the detection limit of the method used (0.02 µg/L). With regard to cyanides, all the analysed fresh mud samples had contents higher than the standard of culture setting in force in Burkina Faso (0.5 mg/kg). Water taken from Sissamba school « A » water pump, contained 0.12 mg/L of cyanide. This study highlighted many health and environmental problems on the gold panning sites in Burkina Faso.

Keywords : gold panning, risk, health, environment