Physicochemical, heavy metal and mineral elements assessment of waters from four rivers along Benin-Agbor road in Edo state, Nigeria

Abstract

The Benin-Agbor road is a major road linking Edo State and the Eastern states of Nigeria, characterized by daily vehicular movements. The inhabitants of the area depend on the river waters mainly for their domestic purposes. It was against the above background that this research was conducted in order to assess the suitability of the waters from four rivers for drinking purposes and the possible hazards the inhabitants may be exposed to. Twenty-two parameters were determined which have relationship with water quality assessment by using recommended methods. Results from the sampling sites indicate that some of the parameters were within the permissible limit recommended by World bodies like the World Health Organization (WHO), whereas other parameters were above the permissible limit like the iron with a range of 2.08 ± 0.02mg/L to 19.90 ± 0.20mg/L; manganese 2.20 ± 0.10mg/L to 5.80 ± 0.20mg/L and lead 0.02±0.00mg/L to 0.17±0.00mg/L. The physicochemical parameters like P^H, colour, electrical conductivity, turbidity, total solids and chemical oxygen demand of the waters of the four rivers ranged between 6.50 ±0.10 and 6.30±0.10; 49.70±0.20 and18.00±0.00(Hazen); 80.00±0.10 and 19.30±0.00 (μ/cm);14.60 ± 0.20 and 4.25 ±0.20(NTU);10.50 ± 0.30 and4.30 ± 0.00(mg/L);26.00 ± 0.00 and 8.80 ± 0.20(mg/L) respectively. The continuous ingestion and accumulation of the excess heavy metals like lead whose concentration was higher than the permissible level in drinking water might result in serious health disorders.

Keywords: Physicochemical, Anion, Cation, River waters, Edo State