Heavy metal content and health risk assessment of a South-eastern Nigeria River

An enormous deficiency lag exists in the demand and supply of potable water in Umuahia, Abia State, Nigeria. The people have to pay lots of money to get potable water from water vendors, and those who cannot afford to pay patronize other unwholesome sources. Ossah River, one of the local drinking water sources, was studied to assess the heavy metal content and health risk assessment vis-a-vis its suitability for human consumption. Eight (8) heavy metals (Mn, Cu, Pb, Fe, Zn, Cd, Cr and Ni) were assessed between January and June 2018 in 3 stations, using atomic absorption spectrometer, and compared with Nigerian drinking water standards. Some of the heavy metals evaluated exceeded standards and warranted health risk assessment. Health risk assessment for all the stations indicated that there is no particularly dangerous single heavy metal, but their cumulative effect, indicated by the hazard index (HI). HI for all the stations highly exceeded threshold value (1). This calls for concern for both adults and children exposed to the water through ingestion. The heavy metal contamination observed was geogenic, exacerbated by anthropogenic activities.