| Abstrakt: |
Mining activities in developing countries, particularly Nigeria, have become a significant public health concern due to contamination of water resources. This study integrates geochemical, spatiotemporal, and probabilistic health risk assessment models to evaluate pollution vulnerability in surface and groundwater and its public health implications. Twenty-one water samples were analyzed for their physicochemical properties. Both the groundwater and surface water were moderately acidic (pH 5.8–6.1), fresh, and hard. Potentially toxic elements (PTEs) concentration occurred as Mn > Pb > Fe > Cd > Zn > Ba and Mn > Pb > Cd > Zn > Fe > Ba for the surface and groundwater respectively. All the PTEs (except Fe, Ba, and Zn) exceeded their permissible limits. The water quality index (WQI) and the overall index of pollution (OIP) revealed that 52.3% and 66.6% of the water samples, respectively, are unsuitable for drinking. The trend of distribution of PTEs in the water increases towards the southwestern direction. The PHREEQC model revealed that some heavy metals (e.g., Cd, Ba, Pb) occurred in their hydrated mineral phases at the current water pH range of 5.82–6.03, this reduces their bioavailability in water. Hierarchical cluster analysis identified NO3, pH, NO2, Cd, BOD, and Salinity in five water samples (STRM6, PND3, PND6, BH3, BH4) as the major contributors to the water contamination while Mn, Fe, and Zn were identified to have the least contribution to contamination. Meanwhile, principal component analysis showed very high principal component loading (p > 0.9) for Temperature and pH in groundwater; indicating that these parameters had more influence on the enrichment of contaminants in groundwater than in surface water. The total cancer risk (CRtot) for oral ingestion of water occurred above the U.S Environmental Protection allowable limits of 1.0E−6 and 1.0E−04. The children population showed greater exposure risks to cancer compared to adults from the ingestion of Pb and Cd in drinking water. The findings from this study underscores the significance of an integrated approach for the effective prediction of water pollution vulnerability and human health risks, particularly in Nigeria, where data on environmental monitoring is a concern. |
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