Environmental Impact of Artisanal and Small-Scale Gold Mining in Borgu Local Government Area

Abstract

This study was conducted to assess the environmental impact of artisanal and small-scale gold mining in Borgu Local Government Area, Niger State, located in North Central Nigeria. Samples were gathered from areas presumed free of gold mining activities to serve as controls, as well as from gold processing (washing) sites and downstream locations along Mayera water. These samples were analysed at the National Institute for Freshwater Fisheries Research (NIFFR) central laboratory for heavy metals using atomic absorption spectrometry (AAS). The levels of cadmium, copper, chromium, iron, lead, and mercury were measured using AAS techniques. The concentrations found in samples from the control site (upstream) are cadmium (0.001mg/L) copper (0.006mg/l), chromium (0.025mg/l), iron (.01mg/l) lead (0.009mg/l) and mercury (.0088mg/l) are all below the acceptable permissible limit of WHO/NAFDAC. While the result from the mining processing (washing) site show a very high increase in the heavy metal concentration of cadmium (0.008mg/L) copper (0.032mg/l), chromium (0.091mg/l), iron (0.447mg/l) lead (0.032mg/l) and mercury (0.031mg/l).the mean concentration of cadmium are (0.0.0058mg/l),chromium(0.027mg/l) and iron (0.1624) on(0.1624mg/l) are below the acceptable permissible limit of NAFDAC while copper(0.02mg/l),lead(0.0257mg/l) and mercury(0.0267mg/l)are above the acceptable permissible limit of NAFDAC. Cadmium (0.0.0058mg/l), copper (0.02mg/l), chromium (0.027mg/l) and iron (0.1624) are below WHO limit while, lead (0.0257mg/l) and mercury (0.0267mg/l)/l) are above the acceptable permissible limit of WHO. The result shows heavy metal concentration due to artisanal and small-scale mining activities in the Borgu local government which is the most silent but significant environmental side effect.