ASSESSMENT OF WATER POLLUTION IN RIVER ETHIOPE: A COMPREHENSIVE STUDY OF POLLUTION LEVELS AT OBIARUKU, ABRAKA, AND SAPELE, AND THEIR POTENTIAL IMPACT ON MARINE ECOSYSTEM

The River Ethiope, a vital freshwater system in southern Nigeria, has experienced escalating pollution due to industrial activities, agricultural runoff, and domestic waste discharges. This study assesses the chemical pollution levels of the river at Obiaruku, Abraka, and Sapele and evaluates their impacts on the aquatic ecosystem, particularly fish health and abundance. Key physicochemical parameters (e.g., pH, DO, BOD, TDS), heavy metals (Pb, Zn, Cu), and nutrients (nitrate, ammonia) were analyzed. Biological data were collected through field sampling of fish species across the three sites.Results indicate significant spatial variation in pollution and ecological impacts. Abraka recorded the highest fish abundance (82 individual species ), while Obiaruku had the lowest (14 individual species ). Ammonia and heavy metals displayed locationspecific effects, with copper. However, no statistically significant relationship was found between pollutant concentrations and fish deformities.These findings highlight the urgent need for sitespecific pollution control measures, continuous monitoring, sustainable waste management, and policy intervention to restore the ecological integrity of River Ethiope.