Phytoremediation Potential of Ficus Benjamina for the removal of Naphthalene, Acenaphthene and Phenanthrene in Contaminated Soil

Abstract

This study was undertaken to evaluate the phytoremediation potential of Ficus Benjamina plant for the removal of polycyclic aromatic  hydrocarbons (PAHs): Acenaphthene (ACN), naphthalene (NAP) and phenanthrene (PHE) from contaminated soil. The plant was  transplanted into pot containing 4 kg soil spiked with the PAHs: ACN, NAP and PHE at concentrations of 1600, 2000 and 2400 mg  respectively. A separate pot with untreated soil was used as a control. Irrigation was done with 600 mL of water after every three days in  the evening hours for eight weeks. Samples of the plant and soil were collected at the end of the phytoremediation process; the plant  was washed with tap water and carefully separated into roots and shoots, dried along with the soil, ground and sieved. The sieved soil,  roots, shoots of the experimental plant as well as that of the control were analyzed for the levels of PAHs: ACN, NAP and PHE following  Soxhlet extraction with 200 mL of dichloromethane-acetone (1:1 v/v) at 60 ^oC for 6 hours using high performance liquid chromatography  (HPLC). The bioconcentration factor (BCF) in mg/kg and the Translocation Factor (TF) in mg/kg of Ficus Benjamina for ACN, NAP and PHE  were (1.76 and 0.47), (0.54 and 2.7) and (0.93 and 0.68) respectively. The results generated in this study have demonstrated that the  different concentrations of the PAHs (NAP, ACN and PHE) in root, only NAP was transferred to the aerial parts of the plant and this  suggests the suitability of Ficus Benjamina for the phytoremediation of NAP.