Accumulation of metals in weed species grown on the soil contaminated with industrial waste and their phytoremediation potential

Phytoremediation is an eco-friendly, economically feasible and emerging technique for the restoration of environment contaminated with heavy metals. Present study was conducted to determine the heavy metal accumulation potential of twelve native weed species viz. Calotropis procera, Croton bonplandianum, Cyperus rotundus, Datura stramonium, Euphorbia hirta, Parthenium hysterophorus, Phyllanthus amarus, Sida cordifolia, Solanum nigrum, So lanum xanthocarpum, Spinacia oleracea and Tridax procumbens growing naturally in the field at Lucknow UP, India. Heterogeneous accumulation of metals was found among the different weeds. Moreover, metal accumulation varied within the plant tissues i.e. roots and shoots. The concentration of Cr, Cu, Ni, Pb and Cd in the root tissues were found in the range of 3.97-67.72, 3.44-45.47, 2.52-14.19, 6.13-58.28 and 0.32-3.96 mu g g(-1) whereas the corresponding shoot values were 5.45-125.67, 2.87-19.60, 1.81-15.39, 5.18-44.28 and 0.23-3.17 mu g g(-1) respectively. Among the different plant species the translocation factor (TF) ranged between 0.453-1.938, 0.136-3.236, 0.346-2.065, 0.277-3.857 and 0.119-3.314 for Cr, Cu, Ni, Pb and Cd respectively. All the plants were found to have an enrichment coefficient of >1, which reflects their high metal accumulation potential. Findings suggest that studied weed species may be used for the phytoremediation and restoration of land contaminated toxic metals. (C) 2013 Elsevier B.V. All rights reserved.