Phytotransformations of Perchlorate Contaminated Waters

• Published in: Environmental technology 2000-09, Vol.21 (9), p.1055-1065
• Main Authors: Susarla, S., Bacchus, S. T., Harvey, G., McCutcheon, S. C.
• Format: Article
• Language: English
• Subjects: Applied sciences; Biological and medical sciences; Biological and physicochemical phenomena; Biological treatment of waters; Biotechnology; Environment and pollution; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Industrial applications and implications. Economical aspects; ion-chromatography; kinetics; Natural water pollution; Perchlorate; phytotransformation; plants; Pollution; Water treatment and pollution
• ISSN: 0959-3330; 1479-487X
• DOI: 10.1080/09593332108618049

Six vascular plant species (sweet gum, black willow, pickleweed, smartweed, water-lily and duckmeat) were used to determine the uptake and transformation of perchlorate at three concentrations (0.2, 2.0, and 20.0 mgl −1 ) for 10 days under laboratory conditions. Perchlorate uptake followed a first-order reaction, with rate constants ranging between 0.001 to 0.007 h −1 . Accumulation of perchlorate was between 0 to 981 mg kg −1 of plant weight for various plants. Based on the results the accumulation of perchlorate was in the order: smartweed > pickleweed > sweet gum > water-lily > willow. Analysis of plant tissues (roots, stems, and leaves) confirmed the presence of transformation products, chlorate, chlorite and chloride. The distribution of perchlorate and its products indicate that the transformation reaction occurred in each tissue independently of the other and accumulation of byproducts was significantly higher in leaves than in roots or stem. No external signs of perchlorate toxicity were observed at these high concentrations in plant tissues suggesting that these plant species show potential for phytoremediation.