CONCENTRATIONS OF SEVEN HEAVY METALS IN THE LEAVES OF OIL PALM TREE (ELAEIS GUINEENSIS) AND ALMOND TREE (PRUNUS DULCIS) IN STEEL PRODUCTION AREAS OF DELTA STATE, NIGERIA

Samples of leaves of two species of plant: oil palm tree (Elaeisis guineensis) and almond tree (Prunus dulcis) were collected from seven sampling stations in the steel production areas of Ovwian and Aladja Towns in Delta State, Nigeria each season (dry and rainy) for two years and analyzed for heavy metals by methods of mixed acid digestion and flame AAS. Results shows that average concentrations of heavy metals in oil palm are: Cu (49±18 mg/kg), Pb (114±91 mg/kg), Ni (21.9±5.6 mg/kg), Cd (6.8±2.0 mg/kg), Zn (250±120 mg/kg), Fe (1020±240 mg/kg), and Mn (430±220 mg/kg), and in almond leaves are: Cu (212±83 mg/kg), Pb (190±120 mg/kg), Ni (24.9±8.0 mg/kg), Cd (8.3±3.1 mg/kg), Zn (680±440 mg/kg), Fe (1230±590 mg/kg) and Mn (1000±640 mg/kg). Concentrations of heavy metals in the study area are significantly higher than the concentrations of corresponding metals in control area.