Phytoremediation of anthracene- and fluoranthene contaminated soil by Luffa acutangula

Abstract

Phytoremediation of soil contaminated with anthracene and fluoranthene, either alone or together, by ridge gourd (Luffa acutangula) was investigated through laboratory pot experiments in a greenhouse for 45 days. The i nitial concentration of anthracene or fluoranthene was 100 mg kg -1 when each was spiked alone. When spiked together, the initial concentration of each hydrocarbon was 50 mg kg -1 . The ridge gourd grew normally in anthracene-contaminated soil based on assessment of shoot growth at the end of the experiment. Fluoranthene spiked either alone or together with anthracene was toxic to the plant as shown by significantly reduced shoot and root growth, especiall y on day 45 after transplantation. Planting of ridge gourd was more effective in decreasing the amount of anthracene and fluoranthene from soil than un-planted control during the 45-day experiment. Only 0.5-1.8% and 3.1-14.1% of anthracene and fluoranthene respectively were detected in planted soil on day 45. In contrast, 27.7-48.2% and 46.9-73.8% of anthracene and fluoranthene respectively, spiked alone or together, remained in the control un-planted soil during the same period. The two aromatic hydrocarbons were neither detected in the shoot nor root tissue of the ridge gourd, which suggests that phytostimulation may be the most likely mechanism by which these hydrocarbons were removed from soil.

Keywords

• phytoremediation
• anthracene
• fluoranthene
• Cucurbitaceae
• ridge gourd
• Luffa acutangula