Assessment of Water Quality Index and the Probable Human Health Implications of Consuming Packaged Groundwater from Abeokuta and Sagamu, Southwestern Nigeria

Background: Contamination of groundwater could result in serious and irreparable health problems for consumers. This study assessed the water quality and human health implications of metals in packaged groundwater from Abeokuta and Sagamu, southwestern Nigeria. Methods: One hundred and forty bags of the packaged groundwater were purchased and analyzed for physical and chemical parameters using standard procedures, while metals were determined using inductively coupled plasma optical emission spectrophotometry. Risk assessment of metals was estimated using hazard index (HI), hazard quotient (HQ), and cancer risk (CR). Water quality index (WQI) was also evaluated. Results: The observed physical and chemical parameters, except Mn and Fe, in the packaged groundwater samples were observed to be within the permissible limits of the World Health Organization. The WQI data indicated suitability for drinking purposes. The health risk data indicated high HQs > 1.0 for Ca (for adults and children at all the monitoring sites), Mn (children at all the sites, and adults at six sites), Mo (children at four sites, and adults at three sites), and Cu (children at three sites and adults at one site). Conclusion: The CRs of the packaged groundwater for Co and Ni at many sites revealed values > the acceptable limit of 1 × 10 −4 , indicating possible development of cancer by the consumers.