METAL CONCENTRATION IN PLANT TISSUES OF JATROPHA CURCAS L GROWN IN CRUDE OIL CONTAMINATED SOIL (Published)
This study evaluated the heavy metal concentration in plant tissues of Jatropha curcas grown in crude oil contaminated soil in Asaba, Delta State, Nigeria in 2010. 0.0, 2.0 4.0, 6.0, 8.0 and 10.0% w/w of the oil constituted the treatments. The results showed a build up of heavy metals in areas of oil impact as the levels of heavy metals including iron, zinc, cadmium, copper, manganese, lead, chromium and nickel were significantly higher (P£0.05) in contaminated soils when compared to the uncontaminated subplots. Plant tissues (leaves, stems and roots) analyses also showed significantly higher amounts of heavy metals compared with values obtained from areas not contaminated with crude oil. Although the amounts of metals observed in the present study are below tolerable limits according to World Food and Agricultural Organization and Federal Environmental Protection Agency, with gradual accumulation and biomagnifications of these non-biodegradable elements, a rise to a dangerous or lethal level with their inherent health risks could be envisaged in man and his animals.