Effects of Illegal Gold Mining Activities on heavy Metal Content of Soil in Chanchaga, Niger State

Abstract

This field study was conducted to assess heavy metal concentrations in soils as a result of illegal gold mining activities around the mining site in Chanchaga Village in Niger State, Nigeria. Gold mining and exploration has been identified as the major activity in this area. Soil samples obtained at distances of 10, 20, 30, 40, 50 and 60m from the mining site and soil outside the mining site as control were obtained, digested and analysed for the concentrations of heavy metals like zinc, lead, copper and chromium using standard methods. These toxic heavy metals were observed to be significantly present in high concentrations in the soil samples obtained from the gold mining farm site when compared to the soil sample obtained outside the mining environment and World Health Organisation maximum permissible standard. The heavy metal concentrations of zinc and copperobserved in the control sample were 3.0 and 1.42milligram per kilogram respectively and all were lower than those obtained from the soil samples at the gold mining site while leadand chromium were not detected. This implies that illegal gold mining activities has contaminated soil in the mining site with the presence of toxic heavy metals.