Abstract

Groundwater is considered a good source of water for drinking and other domestic purposes because of its perceived low contamination. This study investigated metal concentrations in groundwater from five randomly selected location in Abakaliki metropolis of Nigeria. This is aim to evaluate the human health risk of metals via oral and dermal exposure to drinking groundwater using non-cancer and cancer health risk in Abakaliki metropolis of Nigeria. There was significant (p ≤ 0.05) difference between the mean concentration of As, Pb, Ni, Cd, Cr, Mn, Se and K in all the study area compared with the permissible limit. None of the metals analysed was detected in the treated water used as a standard. Average Daily Dose (ADD) values were 100 to 150 times higher than Dermal Daily Dose (DAD) contact pathway, indicating that human exposure to these metals via ingestion is the most significant exposure
pathway. Hazard quotient (HQ) values of As, Pb, Cd, Cr, Mn, V and Se far exceeded the safe reference dose (HQs ˃ 1). This study indicated that the exposed population in the area are at risk to non-carcinogenic adverse health effect, especially to Pb and Cd with the highest total HQ (12 – 83% above 1).The estimated Lifetime of Carcinogenic Risks (LTCR) for all the analyzed
metals exceeded the predicted lifetime risk for carcinogens from the ingestion pathway. This study indicates potential non-carcinogenic and carcinogenic human health hazard from groundwater intake around Abakaliki region via oral ingestion.