Levels of heavy metals in a groundwater around a municipal solid waste dumpsite in bauchi, nigeria: assessing the health impact

This study assessed the levels of heavy metals in a groundwater around a Municipal Solid Waste (MSW) dumpsite in Bauchi, Nigeria.  Health risk parameters were determined to evaluate the health risk impact via oral consumption. The groundwater samples were collected from fifteen boreholes around a six different (MSW) dumpsite and analysed for (Ni, Cd, Mn, Cr, Pb, Cu and Zn) using Atomic Absorption Spectroscopy (AAS). The health risk was determined using; chronic daily intake (CDI), hazard quotient (HQ) and total hazard index (THI) for children and adults. The metal concentrations (mg/L) ranged from Ni (0.00-0.012), Cd (0.00-0.002), Mn (0.013-0.19), Cr (0.00- 0.0022), Pb (0.001-0.03) Cu (0.028-0.100) and Zn (1.39-3.11). The results revealed that the concentrations of Cd, Ni, Cr, Mn, and Cu were below the acceptable limit set by World Health Organization (WHO, 2008) and Nigerian Standard for Drinking Water Quality (NSDWQ, 2015) while Pb and Zn were above limits in some samples. The calculated values for chronical daily intake (CDI) were found in the order of Zn >Mn > Cu > Pb > Ni > Cd > Cr for children, while Zn > Mn > Cu > Ni > Pb > Cr > Cd for adults. The hazard quotient (HQ) values of Cu and Zn were above one for children in some samples, while below one in other studied metals for children and adults. The total hazard index (THI) values > 1, for children these values indicated that the children were of high risk for non-carcinogenic adverse health effect. Keywords: Assessment, Hazard quotient, Hazard index, Health risk, Heavy metals