Phytoremediation Potential of Plants Growing on the Pb-Contaminated Soil at the Song Tho Pb Mine, Thailand

Abstract

© 2017 Taylor & Francis Group, LLC. The contamination of lead (Pb) is one of the main environmental problems on a global scale. This study assessed the potential of native metallophytes growing on the Song Tho Pb mine in Kanchanaburi province, Thailand, by a field survey. Plants and the associated soil samples were collected. Total Pb concentrations were analyzed by a flame atomic absorption spectrophotometer after a microwave-assisted acid digestion. While total Pb concentrations of top soils varied from 4881 to 16,720 mg/kg, those in soil around the roots ranged from 421 to 48,883 mg/kg. A total of 12 species belonging to eight families accumulated Pb concentrations in roots (47–32,633 mg/kg) which were higher than those in shoots (non-detected values–1489 mg/kg). Bidens pilosa, with Pb accumulation in shoots > 1000 mg/kg and translocation factor (TF) > 1, could be useful in phytoextraction as a hyperaccumulator. Thysanolaena latifolia and Mimosa pudica with bioconcentration factor > 1 and TF < 1 could be useful in phytostabilization as excluders. So far, not many Pb hyperaccumulators are reported. The results from this study proposed a new candidate, B. pilosa, for Pb extraction. The potential use of these three phytoremediators should be further investigated using hydroponic and pot experiments.