Mercury contamination in artisanal gold mining area of Manyera river , niger state Nigeria

The study was conducted on Manyera River, Niger State Nigeria due to the mining activities in the area as the river is mainly used as the source of livelihood of people around it. Samples of water, fishes and sediments were collected along the river course in March, 2013. Samples were persevered and taken to the laboratory for analysis by Cold Vapor Atomic Absorption Spectrometer. The water collected at SBW5 downstream had the highest concentration of 0.025mg/L and lowest value was recorded from upstream where there’s little or no mining activity with concentration of 0.014mg/L. The concentration of fish obtained from the river (Heterotis niloticus) is 0.008mg/L, although no fishing activity where the mined soil is been washed. Sediment collected downstream also had the highest concentration of mercury of 0.021mg/L while at point where the mined soil is washed showed lower concentration of 0.015mg/L. These values were high compared to 0.001ppm standard limit for environmental matrices by WHO. There is need to continually monitor this activity to prevent the outbreak of problems associated with Mercury poisoning as the water is the only source of livelihood for domestic activities in the communities around it.