Benefits of phytoremediation amended with DC electric field. Application to soils contaminated with heavy metals.

The objective of this study was to determine the influence of the DC electric current in the physicochemical properties of soil. The electric current may induce changes in pH and electric conductivity that will be reflected in the distribution of the electric potential in the soil specimen. This information will be used for the development of a phytoremediation technology amended with electric current. The results showed that low or moderate voltage gradients (0.67 V/cm) induced small changes in physicochemical properties of soil that do not compromise plant survival. The selected voltage gradient was used in electro-phytoremediation tests in soil contaminated with heavy metals (Cd, Co, Cr, Cu, Pb and Zn). Two plants species adapted to the soil and climate conditions were selected (Brassica rapa L. subsp. rapa and Lolium perenne L.). The electric field enhanced the plant growing, mainly in L. perenne, and increased the phytoremediation of the 6 metals. Mixed cultures of the two plant species showed interesting results for large scale applications.