The Study of heavy metal was carried out at mechanic village along Abeokuta-Ibadan Expressway for the presence of heavy metal and uptake efficiency of plant species as a means of phytoremediation. The concentrations of heavy metals determined from the soil of the mechanic village and compared to a control farmland located as Federal University of Agriculture. The soil sample collected at the base of different species of tree showed that the heavy metals were below permissible levels (FAO/WHO standard) and show no significant difference in the range of mean. Absorption of heavy metals by the bark of the trees in the mechanic village was evident when compared relatively to the presence and uptake of the heavy metals from the soil by tree in the average farmland. The mean concentrations of the heavy metals in the soil of the farmland are in this order of magnitude Cd>Cu>Pb, while the mean concentration of the heavy metals in the soil of the mechanic village are in the order of magnitude Pb>Cu>Cd. Lead has the least concentration in the farmland, while in the mechanic village, it is the predominant heavy metal detected which also shows greater significant different at p<0.05 with a value of 24.34 mg/kg which indicates area of high mechanic activity. While the concentration values of heavy metals in the barks in comparison to the FAO/WHO and EC/CODEX standard for these heavy metals shows that the concentration of the heavy metals in those vicinities is within the normal range for cadmium and copper, but the lead present is above the WHO/FAO standard at 0.299 mg/kg and close to the EC/CODEX standard. It can also be concluded that the uptake efficiency of heavy metal under study of the three species are in the order magnitude Mango>Cashew>Neem. We can also recommend that for better efficient cleanup especially where an area is polluted with copper, mango is best bet for the uptake of such metal while if an equal proportion all many heavy metals are evident then it will be better to use Neem as a phytoremediating plant.
 

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