Phytoremediation as a prospective method for rehabilitation of areas contaminated by long-term sewage sludge storage: A Ukrainian-Greek case study

Soil contamination by heavy metals could be caused by long-term storage of sewage sludge on the territory of most municipal wastewater treatment plants (WWTPs) worldwide. Different methods to deal with heavy metal pollution and rehabilitation can be applied, but they are costly. Phytoremediation is a method using plants in order to extract, sequester and/or detoxify pollutants such as heavy metals. Phytotechnologies are more advantageous economically, than other in situ and ex situ remedial approaches (they estimated to be at least 40% less costly) (ITRC, 2001). In this work the suitability of several plant species for phytoremediation under natural conditions was studied. Brassica napus, Medicago sativa, Zea mays. Triticum aestivum and Hordeum vulgare were grown in pots with sewage sludge from Bezludivka WWTP in Kharkiv, Ukraine and from Sindos WWTP in Thessaloniki, Greece. Plants in the experimental series were compared to those in the control samples (the same species grown in compost). In experimental series, shoot growth was less reduced in T. aestivum and H. vulgare than in the other plant species studied. M. sativa had the lowest germination rate. Generally B. napus and M. sativa, giving less biomass production than Z. mays and T. aestivum, were characterized by higher ability to accumulate heavy metals (Cd, Cu, Ni, Pb, Zn, Cr, As and Hg). (C) 2009 Elsevier B.V. All rights reserved.