Assessment of Heavy Metals Concentrations around Automobile Mechanic Workshops in Ilaro, Ogun State.

Abstract

This research study was carried out to assess the heavy metals in soils around Automobile Mechanic Workshops in Ilaro, Ogun State, Nigeria. The concentration of Chromium, Zinc, Copper, Cobalt, Lead and Nickel were measured within the study area, the samples were collected from the environment of the automobile mechanic workshops and cultivated farmland. The Farmland samples serve as a control. A total of 10 samples were collected, three samples from the farmland and seven from the selected Automobile Mechanic Workshops. At the laboratory, the wet digestion method was used for the samples preparation. Thereafter, Atomic Absorption Spectrophotometry (AAS) was employed in determining the level of heavy metals concentrations in the soil samples. The values of the measured concentration from soil samples of the automobile mechanic workshops for Zn, Cr, Cu, Pb, Co and Ni ranged from 62.416 to 81.163 mg/kg, 8.314 to 12.678 mg/kg, 15.078 to 18.402 mg/kg, 81.697 to 84.128 mg/kg, 12.070 to 14.112 mg/kg and 28.162 to 30.456 mg/kg respectively having mean values of 70.115 mk/kg, 10.315 mk/kg, 16.470 mk/kg, 82.731 mk/kg, 12.739 mk/kg and 29.361 mk/kg respectively. The results show that the mean values of concentration of the heavy metals were below the WHO/FAO standard values, except for Zn which is higher than the WHO/FAO standard value of 60 mg/kg. The result of the study calls for strict regulations from concerned health authorities as regard waste management strategies to checkmate the disposal of these harmful wastes in form of used oils within the mechanic workshop and its environs to prevent further contamination of the environment.