Removal of total petroleum hydrocarbons from polluted urban soils of the outskirts of Ahvaz, southwestern Iran

Earlier phases of economic expansion and urban development have resulted in significant sources of urban soil contamination. Petroleum hydrocarbons are one of the most common groups of persistent organic contaminants in the environment. In this study, two types of treatment in 3 concentrations were prepared that were included plant treated by 1% oil pollution, treatment by 1% contamination without plant (as control), plant treated by 5% oil pollution, the 5% pollution treatment without plant (control), 10% oil pollution treatment with plant and 10% treatment without plant (control) that 3 replicates were prepared for each treatment. The obtained extracts were concentrated to 1 mL under a gentle stream of nitrogen gas, and then 2 μg of the sample was injected into a UNICAM 610 series gas chromatograph equipped with a flame ionization detector. Primary Total petroleum hydrocarbons amount in 1%, 5% and 10% concentration was respectively: 9027.40 mg/kg, 49599.03 mg/kg and 99548.28 mg/kg. After 4 months its amount in different concentration with plant was 126.43 mg/kg, 4463.92 mg/kg and 19611.50 mg/kg. The best total petroleum hydrocarbons removal efficiency was observed in all concentration at 120th day. The results of this study showed that vetiver can remove petroleum hydrocarbons from contaminated soils effective.