Preliminary note on potential use of forage crops for soil phytoremediation of dieldrin

The aim of this trial was to evaluate the feasibility of using tall fescue (Festuca arundinacea) and alfalfa (Medicago sativa) for phytoremediation of dieldrin. Experimental trial was carried out in greenhouse with temperature and light control. Each tested crop were seeded in individual pots (10 plants/pot) filled with contaminated soil (47 microg/kg dieldrin) and uncontaminated soil collected in sites located in the province of Latina (Italy). Samples of soil, root, and aerial part of plants were analysed at 3 and 6 months after seeding. The analytical determinations in soil and plant samples were carried out by GLC-ECD and confirmed by GLC-MS. After 6 months in the greenhouse, recoveries of dieldrin from soil planted with tall fescue and alfalfa were significantly lower than recoveries in unplanted control soil. Dieldrin residue values in root did not differ between the two different sampling times for each forage crop tested, but they were always higher in fescue than in alfalfa. Residue levels in aerial part were low (< 10 microg/kg) in the two forage crops. Preliminary results seem to confirm the ability of tested plants to enhance dissipation of dieldrin in soil at low level of contamination.