Ecology & Safety, Volume 14, 2020

Rezumat: A field study was conducted to evaluate the efficacy of sedum plumbizincicola for phytoremediation of contaminated soils in Bulgaria. The experiment was performed on an agricultural field highly contaminated (2540.8 mg/kg Zn, 2429.3 mg/kg Pb and 51.5 mg/kg Cd) by the Non-Ferrous-Metal Works near Plovdiv, Bulgaria. Upon reaching the stage of flowering, the sedum plumbizincicola plants were gathered. The content of heavy metals, micro and macroelements in different parts of sedum plumbizincicola (roots, stems, leaves) was determined by ICP. The chemical composition of root exudates of sedum plumbizincicola was determined by gas chromatography–mass spectrometry. Thirty compounds were identified in the root exudates, of which 6 were saccharides, 9 amino acids, 5 organic acids, 8 sugar acids and alchohols and 2 other compound (hexadecanoic acid, octadecanoic acid). Significant differences were found in the content of the elements in the different parts of sedum plumbizincicola. Pb, Cd, Zn, Cu, Ca and P accumulate in the leaves, while Fe, Mn and Mg accumulate in the root system. Sedum plumbizincicola can be referred to the hyperaccumulator of cadmium and the accumulators of zinc and lead. The high concentration of Cd, Zn and Pb in the leaves and the high translocation (TFZn – 4.21, TFCd - 2.11, TFPb – 2.72) and high bioconcentration factors (BCFCd - 22.68, BCFZn - 2.20) indicate the possibility of sedum plumbizincicola to be used in phytoextraction of heavy metal contaminated soils in Bulgaria.