Impact and Health Risk Assessment of Groundwater in the Vicinity of Dumpsites in Keffi Metropolis, Nigeria

This study investigated the hydrogeochemical characteristics of groundwater impacted by waste dumps through computation of different hydrogeological/chemical indices and related health risk assessment of major heavy metals (HVM) in relation to different population groups in Keffi Metropolis. Samples from ten (10) groundwater sources were collected for analysis. Results revealed that the concentration of major cations from the samples was in the order: Ca2+ > Na+ + K+ > Mg2+, while major anionic constituents were in the order: HCO3- > CO32- > SO42- > Cl- > F- respectively. Water quality index (WQI) computed indicated that the groundwater of the study area is not suitable for domestic purposes particularly drinking as some of the parameters exceed the WHO guidelines. Generally, the HVM hazard quotients (HQ) of non-carcinogenic (NC) and carcinogenic toxicity (TC) for both population groups were lower (HQ < 1) indicating that the groundwater within the study areas did not pose current significant risk. Non-carcinogenic risk uncertainty analysis by Monte Carlo simulations (MCS) further indicated that risk levels of HVM in GW were lower (HQ < 1). Despite the findings in this study, it is important that regular monitoring of GW quality is done in order to ensure that water is potable and prevent human health risks.