Comparison of natural organic acids and synthetic chelates at enhancing phytoextraction of metals from a multi-metal contaminated soil.
Chemically assisted phytoremediation has been developing to induce accumulation of metals by high biomass plants. Synthetic chelates have shown high effectiveness to reach such a goal, but they pose serious drawbacks in field application due to the excessive amount of metals solubilized. We compared the performance of synthetic chelates with naturally occurring low molecular weight organic acids (LMWOA) in enhancing phytoextraction of metals by Indian mustard (Brassica juncea) from multi-metal contaminated soils. Gallic and citric acids were able to induce removal of Cd, Zn, Cu, and Ni from soil without increasing the leaching risk. Net removal of these metals caused by LMWOA can be as much as synthetic chelates. A major reason for this is the lower phytotoxicity of LMWOA. Furthermore, supplying appropriate mineral nutrients increased biomass and metal removal.
do Nascimento
Clístenes Williams A
CW
Universidade Federal Rural de Pernambuco, Departamento de Agronomia, Recife, PE, 52171-900, Brazil.
Amarasiriwardena
Dula
D
Xing
Baoshan
B
D001673:Biodegradation, Environmental; D002614:Chelating Agents / Q000494:pharmacology*; D019343:Citric Acid / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D005707:Gallic Acid / Q000494:pharmacology; D007220:Industrial Waste; D008670:Metals; D009149:Mustard Plant / Q000187:drug effects / Q000378:metabolism*; D009930:Organic Chemicals / Q000494:pharmacology*; D019815:Oxalic Acid / Q000494:pharmacology; D004369:Pentetic Acid / Q000494:pharmacology; D012989:Soil Pollutants; D014641:Vanillic Acid / Q000494:pharmacology
D002614:Chelating Agents; D007220:Industrial Waste; D008670:Metals; D009930:Organic Chemicals; D012989:Soil Pollutants; D019343:Citric Acid; D005707:Gallic Acid; D004369:Pentetic Acid; D019815:Oxalic Acid; D004492:Edetic Acid; D014641:Vanillic Acid