Effects of EDTA on lead uptake by Typha orientalis Presl: a new lead-accumulating species in southern China.

A series of field investigations have been conducted at Yongzhou Pb/Zn/Cu mine tailings, Hunan Province, southern China. The specific aim was to search for new lead accumulators with fast growth rate and large biomass. The results of tissue analyses identified Typha orientalis Presl has a strong accumulation of lead. The average lead concentrations in the leaves and roots are 619 and 1,233 mg/kg, respectively. The growth and Pb content of the plant were also studied by hydroponic culture with different concentrations of Pb(NO(3))(2). Growth of the plant was not affected by Pb up to 300 mg/L. The Pb concentrations in the leaves and roots increased with increasing of Pb level in the modified Hoagland's nutrient solution. The maximum concentrations of Pb in the leaves and roots were 16,190 and 64,405 mg/kg, respectively. The study also demonstrated that EDTA not only increased the amount of Pb taken up by plants but also speeded up the metal translocation from roots to leaves.