Drinking Water Quality, Nitrate and Heavy Metal Quantification, and Health Risk Assessment of Water Sources around a Tsauni Gold Mine, Gwagwalada, Abuja-Nigeria

Mining activities, especially gold extraction, have been widely documented to significantly disrupt the natural environment, often resulting in release of harmful contaminants. This study assesses the drinking water quality in the Babban Tsauni artisanal gold mining community by analyzing physicochemical parameters and heavy metal concentrations, using standard methods. Parameters include pH, temperature, total dissolved solids, conductivity, dissolved oxygen, nitrate, and heavy metals (As, Pb, Ni, Mn, Cr, Zn, Cu). Heavy metal pollution indices and health risks were evaluated. Results show that physicochemical parameters and nitrate concentration were within safe limits, and heavy metal concentrations were in the range of 0.724-2.886, 0.004-0.017, 0.001-0.243, 0.037-6.910, 0.051-0.268, 0.006-0.151, 0.009-0.060 (ppm) for As, Pb, Ni, Mn, Cr, Zn and Cu, respectively. Of the seven heavy metals considered, only Zn and Cu had values within the WHO permissible limit. The contamination factor for Mn was 20.0, with other heavy metals having values of less than 1. However, the overall pollution index for the heavy metals was 0.52, interpreted as non-pollution. There was no severe significant cancer risk, although there may be concern for potential non-carcinogenic effects in children due to As exposure (dermal route, hazard index: 19.27). The study therefore recommends that necessary measures should be taken to prevent potential risk.