Human Health Risk Assessment of Some Toxic Metals in Groundwater Resources in Four Selected Towns of Delta State, Nigeria

Abstract

Aims: The health risk assessment of some toxic metals in groundwater in four selected towns of Delta State, Nigeria was confirmed by this study. Methodology: Ninety six groundwater samples were obtained from sixty four hand-dug wells and thirty two boreholes between December 2016 and May 2017. Samples were analyzed for heavy metals using standard procedures. Data collected was subjected to descriptive and inferential statistics using the Statistical Package for Social Sciences (SPSS) for Windows version 22.0. Health Risk Assessment for Non cancer hazard and carcinogenic effects were determined. Results: The HQ of Cr, Mn and Ni were below 1.0 indicating no threat to the water consumers while the HQ values for Pb, Cd and Cu were above 1.0 indicating risk to human health. The HI value was found to be greater than 1.0, indicating noncarcinogenic adverse effects. The estimated Lifetime of Carcinogenic Risks (LTCR) for Pb, Cr, Cd and Ni exceeded the predicted lifetime risk for carcinogens of 10−6 from ingestion pathway. The groundwater had higher risks of Cr and Cd as LTCR value in most sites were >10−4. The high LTCR should be given high priority as public health is concerned. Conclusions: This study indicated possible non-carcinogenic and carcinogenic human health hazard from groundwater consumption in study area through oral consumption.