Physicochemical Characteristics and Concentrations of Petroleum hydrocarbon and some metals in Surface water of Ajoki River, Ikpoba-Okha Local Government Area, Edo State, Nigeria

The increasing volume of waste generated by industries and households significantly contributes to the degradation of water quality in aquatic ecosystems. Hence, the objective of this paper was to investigate the Physicochemical Characteristics and Concentrations of Petroleum hydrocarbon and some metals in Surface water of Ajoki River, Ikpoba-Okha Local Government Area, Edo State, Nigeria using appropriate standard methods. The results indicated that pH values averaged 7.30 ± 0.22 in the wet season and 7.17 ± 0.20 in the dry season. Polyaromatic hydrocarbons (PAHs) had mean concentrations of 0.01 ± 0.002 mg/L in the wet season but were not detected in the dry season. Chemical Oxygen Demand (COD) values were 20.08 ± 6.06 mg/L and 21.37 ± 5.03 mg/L in the wet and dry seasons, respectively. Cadmium concentrations were 0.02 ± 0.01 mg/L in the wet season and 0.03 ± 0.01 mg/L in the dry season, while lead levels were 0.02 ± 0.001 mg/L and 0.10 ± 0.02 mg/L for the wet and dry seasons, respectively. The Pollution Load Index (PLI) indicated that the Ajoki River was unpolluted during the wet season but became polluted in the dry season. Cluster analysis suggested that the pollutants affecting water quality originated from both natural and anthropogenic sources. These findings highlight the urgent need for sustainable wastewater management practices, stricter environmental regulations, and continuous monitoring to safeguard water quality and protect aquatic life