Chelate-assisted phytoremediation of Cu-pyrene-contaminated soil using Z. mays

This study compares the efficiency of a synthetic chelate (ethylenediaminetetraacetic acid-EDTA), a natural low-molecular-weight organic acid (citric acid), and their combination for phytoremediation of Cu-pyrene co-contaminated soils. Zea mays was grown in each soil and amended with citric acid and/or EDTA to understand the effect of chelates during phytoremediation of contaminated soils. In Cu or pyrene-contaminated soil, plant growth was negatively affected by EDTA (43 %) and citric acid (44 %), respectively, while EDTA + citric acid promoted (41 %) plant growth in co-contaminated soil. EDTA and EDTA + citric acid increased the phytoextraction of Cu in Cu-contaminated and co-contaminated soils, respectively. In pyrene-contaminated soil, all tested chelates increased the dissipation of pyrene reaching 90.4 % for citric acid, while in co-contaminated soil, only citric acid or EDTA + citric acid enhanced pyrene dissipation. These results show that Z. mays can be effective with the help of chelates in phytoextraction of Cu and dissipation of pyrene in co-contaminated soil.