Health risk assessment of heavy metals in the sources of drinking water in parts of Obubra Local Government Area of Cross River State, Nigeria

Abstract

This study examined health assessment of heavy metals in the sources of drinking water in parts of Obubra Local Government Area of  Cross River State, Nigeria. Twenty five (25) water samples were collected with ten (10) from borehole, eight (8) from spring and seven (7)  from dug-well. The samples were analysed using standard laboratory methods. The results showed that Zn had the highest chronic daily  intake for infant, child and adult and Cd the highest hazard quotient in borehole, spring and dug - well water. This indicates that infant is  more vulnerable to health risk followed by child and least by adult. The carcinogenic risk results of Cd and Cr contamination were greater  than the permissible range of ≤1 x 10^-6 to 1 x 10^-4 indicating that the water sources are polluted with Cd and Cr. It was recommended  that there should be awareness programmes on hygienic practices and pretreatment of water before use. Also the Cross River State  Board Limited should supply quality water to the inhabitants and monitor their sources of drinking water.