OLUGBENGA A. EHINOLA AND OLUWATOSIN D. FALUSI
Abstract
Due to the serious environmental destruction caused by exploitation of petroleum resources, Imore and Ilado-odo oil-spill polluted sites in Lagos Creeks were selected for this study. The study is aimed at delineating the extent of pollution due to leakage and vandalization of petroleum products pipeline, ascertaining the possible health hazards and suggesting possible remedial measures. Twenty-five water samples were randomly collected from creeks, hand-dug wells and boreholes of tFe monitoring and control sites. Field parameters such as geographical co-ordinates, elevation, water level, colour, odour, taste and pH were determined. The hydrochemical parameters determined include anions (Cl-, SO42- and HCO3-) by titration, cations (Na+, K+, Ca2+, Mg2+, total Fe and Mn) as well as some trace elements using Inductively Coupled Plasma-Optical Emission Spectrometry technique. The field and laboratory data were processed using Geographic Information System technology to produce geochemical maps. Petroleum hydrocarbons extracted from six water samples were also analysed using Gas Chromatography techniques. Several hot- spots areas of elevated concentrations were identified from the geochemical maps, mainly in the oil spill areas and some of these concentrations exceeded the maximum permissible levels of the WHO Standard and Nigerian Industrial Standard. The petroleum hydrocarbon composition reveal inputs of petroleum products especially gas oil. The inorganic pollutants indicate natural and anthropogenic contribution while the organic pollutants are linked to oil spillage in the study area. Thus, drastic remedial measures should be taken to discontinue the spread of these pollutants and to ameliorate the present detrimental impacts posed to human health and the environment.