Heavy metals concentration and human health risk assessment in groundwater and table water sold in Tudun Murtala Area, Nassarawa Local Government Area, Kano State, Nigeria

Abstract

This study determines the level of some heavy metals and as well assess human health risk due to chronic intake of metals in water samples obtained from Tudun Murtala area of Nasssarawa local government area, Kano state. Results obtained showed that Pb, Cd, Cr, Fe and Zn concentrations in water samples were within the range of 0.295- 0.579, 0.471- 0.529, 0.550- 1.000, 0.3636 - 0.4545, 0.0814 - 0.173 respectively, while the Chronic daily intake calculated for the metals respectively were also within the range of 0.0086 – 0.0165, 0.0135 – 0.0186, 0.0034 – 0.0262, 0.0023 – 0.0049, 0.0104 – 0.0130. The total hazard quotient for non-cancer risk of Pb and Cd were found highly elevated, being at the range of 21.5 – 41.25 and 27.0 – 37.2 respectively while that of Cr, Zn and Fe where found to be below the standard limit of one. The hazard index of metals also showed a risk in exposure to Pb and Cd and a tolerable range was observed for Cr, Fe and Zn. The incremental lifetime cancer risk of metals developed through oral route showed elevated level in Pb, Cd and Cr, revealing that exposure to the heavy metals in the water samples posed an unacceptable potential cancer risk. While for the other metals, it showed a less or tolerable risk to the inhabitants.

Keywords: Heavy metals, hazard quotient, hazard index, incremental lifetime cancer risk