Uptake of Weathered DDT in Vascular Plants:  Potential for Phytoremediation

• Published in: Environmental science & technology 2004-11, Vol.38 (22), p.6147-6154
• Main Authors: Lunney, Alissa I, Zeeb, Barbara A, Reimer, Kenneth J
• Format: Article
• Language: English
• Subjects: Applied sciences; Biodegradation, Environmental; Biological and medical sciences; Biotechnology; Cucurbita - metabolism; Cucurbita pepo; DDT - metabolism; DDT - pharmacokinetics; Decontamination. Miscellaneous; Dose-Response Relationship, Drug; Earth sciences; Earth, ocean, space; Effects; Engineering and environment geology. Geothermics; Environment; Environment and pollution; Environmental science; Exact sciences and technology; Flowers & plants; Fundamental and applied biological sciences. Psychology; Industrial applications and implications. Economical aspects; Miscellaneous; Pesticides; Pesticides - metabolism; Pesticides - pharmacokinetics; Plant Roots - metabolism; Plant Transpiration - physiology; Plants - metabolism; Pollution; Pollution, environment geology; Principal Component Analysis; Principal components analysis; Soil and sediments pollution; Soil Pollutants - metabolism; Soil Pollutants - pharmacokinetics; Tissue Distribution; Volatilization
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es030705b

Since the discovery of its insecticidal properties and its subsequent widespread use, DDT [2,2-bis(chlorophenyl)-1,1,1-trichloroethane] has accumulated in the environment, having a wide range of adverse effects on nontarget species. Due to their hydrophobicity, DDT and other persistent organic pollutants are difficult to remove from contaminated soils, and increasingly so through time as weathering occurs. Phytoremediation is an emerging plant-based technology that may be used to cost-effectively remove or neutralize contaminants in the environment. For some phytoremediation strategies, it must first be possible to translocate hydrophobic chemicals across the root and through the shoot via an aqueous transpiration stream. The objective of this study was to compare the ability of five plant varieties (zucchini, tall fescue, alfalfa, rye grass, and pumpkin) to mobilize and translocate DDT. Plants were grown in the greenhouse in soil contaminated with DDT and its metabolites, DDD and DDE (ΣDDT refers to all of DDT, DDD, and DDE) at two concentrations (high ∼3700 ng/g, and low ∼150 ng/g). All trays were covered with laboratory Parafilm to limit volatilization. Cucurbita pepo species (pumpkin and zucchini) achieved the highest translocation and bioaccumulation factors, and also extracted the highest absolute amounts of ΣDDT from both the high and low ΣDDT soils. In the high ΣDDT soil treatment, pumpkin accumulated 1519 ng of ΣDDT in the roots and 57 536 ng of ΣDDT in the shoots, and zucchini accumulated 2043 ng of ΣDDT in the roots and 35 277 ng of ΣDDT in the shoots. With the exception of alfalfa and pumpkin, principal component analysis detected no preferential translocation or transformation of ΣDDT compounds within the plant. The success of the Cucurbita pepo species in this study to extract and translocate such hydrophobic molecules may be related to their high transpiration volume, large above-ground biomass, and composition of root exudates. This suggests potential for their application in phytoremediation.