Lead uptake, tolerance, and accumulation exhibited by the plants Urtica dioica and Sedum spectabile in contaminated soil without additives

Abstract

Specimens of Urtica dioica and Sedum spectabile collected from plants growing at uncontaminated sites were transplanted in Pb-contaminated soil without additives (EDTA, HEDTA) to identify their natural potential for hyper-tolerance and hyperaccumulation of lead. The total content of Pb in the plants was determined by atomic spectroscopy. Our research showed that the concentrated toxic levels of lead (Pb) in Sedum spectabile and Urtica dioica were about 100 or more times higher than those of non-accumulator plants. It can be concluded that these plants have a high natural potential for hypertolerance and hyperaccumulation of lead, since they can hyperaccumulate it without addition of any chelating compounds (EDTA, HEDTA) to enhance lead uptake. This makes them very promising plants for use in phytoremediation of Pb-contaminated sites.