Assessment of remediation Potentials of maize (Zea mays) on sites co-contaminated with Pb and antracene

Abstract

Phytoremediation is a promising technology for the remediation of sites co-contaminated with inorganic and organic pollutants. A pot experiment was conducted to evaluate the remediation potential of Z.mays in soil co- contaminated with Pb and antracene. Pristine sandy loam soils were polluted with Pb chloride salt and antracene at three different levels (50mg/kg of Pb, 100mg/kg of Pb, and 100mg/kg of Pb+100mg/kg of antracene) and laid out in completely randomized design with 3 replicates. Shoot dry matter weight was significantly reduced (p≤0.05) when compared with control treatments by 40% when exposed to100mg kg-1 of Pb. There was a 48% inhibition of shoot dry matter of Z.mays relative to control treatments when 100 mg Pb kg-1 was mixed with 100 mgkg-1 antracene. Root and shoot metal concentration in Zea mays increased with increasing concentration of Pb. The average Translocation Factor (TF < 1 (0.69) obtained suggests that Zea mays predominantly retains Pb in the root portion of the plant. There was a 5% increase in shoot Pb concentration when soil was contaminated with Pb and antracene. The extractable antracene decreased significantly (p≤0.05) in soil planted with Z.mays as well as in pots without maize plant. This accounted for 65 and 72% of antracene dissipation in planted soil and 40-46% dissipation in unplanted soil. This result suggested that Zeamays is a promising candidate for uptake Pb and dissipation of antracene in co-contaminated soils.