Quality of Drinking Water in Selected Coastal Communities of Ondo South Nigeria

Abstract One hundred drinking water samples were collected from ten selected oil polluted riverine communities of Ondo south Nigeria to investigate their quality. Physicochemical parameters using standard methods reveals values of temperature, electrical conductivity, total hardness, total dissolved solid, turbidity, pH and Dissolved oxygen beyond WHO safe limits while chloride and total alkalinity values fell within the limits. All the heavy metals investigated using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP – OES) have higher concentrations than permissible by WHO standards. Most Probable Number technique (MPN) confirmed eighty- six of the water samples to have coliforms with thirty- two of them as faecal coliforms while Gram staining and the IMViC tests confirmed seventy of the samples to haveE.coli. Total petroleum hydrocarbon (TPH) was analyzed using Agilent 7890B Gas chromatograph equipped with a flame ionization detector (FID), fitted with a HP-5 capillary column coated with 5% Phenyl Methyl Siloxane and a mean value of 62.164mg/L was obtained for (TPH). Leaching of metals from rocks, oil spillages, and acid rain associated with gas flaring are possibly responsible for the values of physicochemical parameters and toxic metals recorded while the presence of faecal coliforms andE.colimay be due to poor sanitary systems in the area while the TPH is from various oil spills rampant in the area. Improved waste disposal methods, prevention of oil spillages and proper treatment of effluents from industries should be adopted to improve the potability of water in the study area.