Environmental Monitoring and Human Health Implications of Potentially Toxic Elements in River Water, Akwa Ibom State, Nigeria

The study was conducted at the upper coastal region of Qua Iboe River,Nigeria,between November 2018 and August 2019 (ten months), to access the concentrations of potentially toxic elements (PTEs) and human health risks associated with water from the river via ingestion. Eight PTEs were assessed from the four stations, using atomic absorption spectrophotometer. The findings were compared with Nigerian drinking water quality standards. The spatial mean concentrations of some PTEs (Mn, Cr, Ni, Cd, Fe and Pb) were exceeding the permissible limits due to anthropogenic activities and seasonal influences. The values for heavy metal pollution index (HPI) were exceeded the threshold (100), while comprehensive pollution index (CPI) indicating moderate to heavily pollution. The hazard quotient (HQ) values for Fe and Cr in children and adults, and hazard index (HI) values were exceeded the threshold value of 1. Daily chronic intake (CDI) values for Fe and Cr mostly were above the oral reference dose of contaminant (mg/kg/day). The findings showed that Fe and Cr were the dangerous PTEs contributed to higher HQs and HI values, indicated that the river is not suitable for domestic use via ingestion.