ASSESSMENT OF HEAVY METALS IN WATER CONTAMINATED WITH PETROLEUM PRODUCTS IN KEFFI LOCAL GOVERNMENT AREA, NASARAWA STATE, NIGERIA

This work assessed the presence of heavy metals in water contaminated with petroleum products in Keffi Local Government Area. Two water sampling stations were selected based on the stratified method of sampling of Antau River. Station A was located along Federal Government College Keffi popularly known as Antau Bridge where Agricultural and mechanical activities, with sales of petroleum product took place. Station B was located at Dadin-Kowa known as Gadamanu where human activities such as bathing and washing took place which served as control. The distance between stations is 1km. The procedural plan of this study was monthly sampling of water from both Stations. Materials such as funnel, sampling container, distilled water, conical flask, filter paper, 50ml polypropylene centrifuge tube, cooler were used. Heavy metal concentrations were determined using X - ray Fluorescent Spectroscopy (XRF) at the Center for Energy Research and Training (CERT), Ahrnadu Bello University Zaria. The water parameters of the four samples were determined using the Extech instrument. The result on Physico - chemical parameters revealed the values obtained from contaminated water samples to be pH (7.31), Dissolved Oxygen (1.14), Electrical Conductivity (8.22), Total Dissolved Solid (4.13), Temperature (27.45) and Salinity (0.091) while the controlled Station at point B were pH (7.43), DO (7.35), EC (3.14), TDS (1.54), Temperature (26.75), Salinity (0.094) respectively. From the result obtained, the heavy metal contaminated samples had the following values: Mg (29.3ldb), A1 (218.69±), Si (230.12±), S (1153.65±), Cl (54.25±), Ca (106.56±), Ti (23.66±), Cr (3.15±), Fe (15.92±), Cd (7.54±). For the control sample at point B, the following values were obtained: Mg (27.49±), A1 (223.71±), Si (243.21±), S (94.84±), Cl (23.52±), Ca (28.44±), Ti (32.99±), Fe (16.63±), Cd (7.67±) respectively. The P-value was 0.8105 (p>0.05) for the water quality parameters while for the concentration of heavy metal P-value was 0.2054 (p>0.05), which indicated a non significant difference between the concentrations of elements. However, the concentration values of heavy metals in the contaminated water at Station A and control water samples at Station B were higher than the World Health Organization values (Standard) for drinking water