Evaluation of Water Pollution and Its Public Health Implications in Osinmo Reservoir, Ejigbo, Osun State, Nigeria

Abstract

Water quality is a critical determinant of public health, particularly in developing regions where anthropogenic activities are prevalent. This study evaluated the effects of water pollution on public health, focusing on Osinmo Reservoir in Ejigbo, Osun State, Nigeria. The primary objectives were to the sources of pollution, analyze the physico-chemical and heavy metal properties of the water, and compare findings against World Health Organization (WHO) standards. Water samples were collected monthly between January and March 2019 from two strategic locations: the Midstream (Station A) and the Spillway (Station B). Standard laboratory procedures were employed to analyze concentrations of Lead (Pb), Cadmium (Cd), Iron (Fe), and selected physico-chemical parameters such as pH, turbidity, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), and temperature. Results showed that concentrations of lead, cadmium, and iron in both sampling stations exceeded the WHO permissible limits for drinking water. Turbidity and COD levels were also significantly above standard thresholds, indicating moderate to high pollution. Station B consistently recorded higher pollutant concentrations than Station A, suggesting increased exposure to anthropogenic contaminants such as agricultural runoff and improper waste disposal. Though pH and temperature were within acceptable ranges, the overall water quality was found unsuitable for direct human consumption. The study concludes that Osinmo Reservoir is adversely affected by pollution and poses significant health risks to surrounding communities. It recommends immediate intervention measures including wastewater treatment, strict regulation of agricultural activities, afforestation, and public awareness campaigns to mitigate further degradation and protect public health.