Abstract
Phytoextraction is an emerging technology for non-destructive remediation of heavy metal-polluted soils. This study was conducted to test chelate-assisted phytoextraction of Cu, Pb and Zn using EDTA and canola (Brassica napus L. cv. Petranova) on a moderately polluted industrial soil (loamy sand) in the sub-continental climate of Eastern Austria. The effects of the rate (up to 2.1 g kg−1 soil) and mode (single versus split) of EDTA application on the biomass, water contents and metal concentrations in shoots and roots were investigated along with changes of metal lability in soil and leaching from the root zone in parallel outdoors pot and lysimeter experiments. Labile (1 M NH4NO3-extractable) metal concentrations in soil increased considerably upon application of EDTA, indicating enhanced phytoavailability. However, this was also associated with enormously increased metal concentrations in the leachates collected below the root zone. Enhanced metal labilities and leachate concentrations persisted for more than 1 year after harvest. Metal lability was more enhanced by EDTA in rhizosphere relative to bulk soil, indicating interactions of EDTA with root activities. Shoot biomass and water contents of canola were virtually unaffected by EDTA, revealing that canola can tolerate excessive metal concentrations in soil pore water. Metal concentrations in shoots were increased considerably, but were insufficient to obtain reasonable extraction rates. Split applications were generally more effective than the same amounts of EDTA added at once. Metal concentrations in roots decreased after each application of EDTA, possibly indicating metal removal from roots by free protonated EDTA, but increased again within several days. As the application of chelate-assisted phytoextraction is limited by the risk of groundwater pollution, further work should focus on natural, continuous phytoextraction technologies.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Baker A J M, McGrath S P, Sidoli C M D and Reeves R D 1994 The possibility of in situ heavy metal decontamination of polluted soils using crops of metal-accumulating plants. Resour. Conserv. Recyc. 11, 41–49.
Blaylock J M, Salt D E, Dushenkov S, Zakharova O, Gussman C, Kapulnik Y, Ensley B D and Raskin I 1997 Enhanced accumulation of Pb in Indian mustard by soil-applied chelating agents. Environ. Sci. Technol. 31, 860–865.
Blum W E H, Spiegel H and Wenzel W W 1996 Bodenzustandsinventur. Konzeption, Durchführung und Bewertung. Revised, 2nd ed. Bundesministerium für Land-und Forstwirtschaft, Vienna.
Bunzl K, Trautmannsheimer M, Schramel P and Reifenhäuser W 2001 Availability of arsenic, copper, lead, thallium, and zinc to various vegetables grown in slag-contaminated soils. J. Environ. Qual. 30, 934–939.
Cooper E M, Sims J T, Cunningham S D, Huang JWand Berti WR 1999 Chelate-assisted phytoextraction of lead from contaminated soil. J. Environ. Qual. 28, 1709–17199.
Deutsches Institut für Normung 1995 Soil quality extraction of trace elements with ammonium nitrate solution. DIN 19730. Beuth, Berlin.
Ebbs S D and Kochian L V 1997 Toxicity of zinc and copper to Brassica species: Implications for phytoremediation. J. Environ. Qual. 26, 776–781.
Ebbs S D and Kochian L V 1998 Phytoextraction of Zn by oat (Avena sativa), barley (Hordeum vulgare) and Indian mustard (Brassica juncea). Environ. Sci. Technol. 32, 802–806.
Ebbs S D, Lasat M M, Brady D J, Cornish J, Gordon R and Kochian L V 1997 Phytoextraction of cadmium and zinc from contaminated soil. J. Environ. Qual. 26, 1424–1430.
Epstein A, Gussman C, Blaylock M, Yermiyahu U, Huang J, Kapulnik Y and Orser C 1999 EDTA and Pb-EDTA accumulation in Brassica juncea grown in Pb-amended soil. Plant Soil 208, 87–94.
Grcman H, Velikonja-Bolta S, Vodnik D, Kos B and Lestan D 2001 EDTA enhanced heavy metal phytoextraction: metal accumulation, leaching and toxicity. Plant Soil 235, 105–114.
Hong P K A, Li C, Banerji S K and Regmi T 1999 Extraction, Recovery and biostability of EDTA for remediation of heavy metal-contaminated soil. J. Soil Contam. 8, 81–103.
Huang J W and Cunningham S D 1996 Lead phytoextraction: Species variation in lead uptake and translocation. New Phytol. 134, 75–84.
Huang J W, Chen J, Berti W R and Cunningham S D 1997 Phytoremediation of lead-contaminated soils: Role of synthetic chelates in lead phytoextraction. Environ. Sci. Technol. 31, 800–805.
Kayser A, Wenger K, Keller A, Attinger W, Felix H R, Gupta S K and Schulin R 2000 Enhancement of phytoextraction of Zn, Cd and Cu from calcareous soil: The use of NTA and sulfur amendments. Environ. Sci. Technol. 34, 1778–1783.
Kumar P B A, Dushenkov V, Motto H and Raskin I 1995 Phytoextraction: The use of plants to remove heavy metals form soil. Environ. Sci. Technol. 29, 1232–1238
Lombi E, Zhao F J, Dunham S J and McGrath S P 2001 Phytoremediation of heavy metal-contaminated soils: natural hyperaccumulation versus chemically enhanced phytoextraction. J. Environ. Qual. 30, 1919– 1926.
Luo Y M, Wu L H, Jiang X J, Wu S C and Christie P 2000 Chelate-enhanced phytoextraction of metal-contaminated soils and environmental risk. In Proceedings of SoilRem 2000 (International Conference of Soil Remediation), October 15– 19, 2000, Hangzhou, China. pp. 166–168
Morel F M M and Hering J G 1993 Principles and Applications of Aquatic Chemistry. pp. 338–339. Wiley, New York.
Nörtemann B 1999 Biodegradation of EDTA. Appl. Microbiol. Biotechnol. 51, 751–759.
Puschenreiter M, Stöger G, Lombi E, Horak O and Wenzel W W 2001 Phytoextraction of heavy metal contaminated soils with Thlaspi goesingense and Amaranthus hybridus: Rhizosphere manipulation using EDTAand ammonium sulfate. J. Plant Nutr. Soil Sci. 164, 615–621
Römkens P, Bouwman L, Japenga J and Draaisma C 2002 Potentials and drawbacks of chelate-enhanced phytoremediation of soils. Environ. Poll. 116, 109–121
Rosenkranz D, Einsele G E, Harres M (eds), Prüeß A, Turian G and Schweikele V 1991 Ableitung kritischer Gehalte an NH4NO3-extrahierbaren ökotoxikologisch relevanten Spurenelementen in Böden SW-Deutschlands. Mittlg. Dtsch. Bodenk. Ges. 66, 385–388.
Salt D E, Smith R D and Raskin I 1998 Phytoremediation. Annu. Rev. Plant Physiol. Plant Mol. Biol. 49, 643–668.
Sun B, Zhao F J, Lombi E and McGrath S P 2001 Leaching of heavy metals from contaminated soils using EDTA. Environ. Poll. 113, 111–120.
Vassil A D, Kapulnik Y, Raskin and Salt D 1998 The role of EDTA in lead transport and accumulation by Indian mustard. Plant Physiol. 117, 447–453.
Weissteiner C, Brandstetter A, Mentler A, Unterfrauner H, Wenzel W W and Blum W E H 1999 EUROSOIL 7 — a representative for Alpine regions. In EUROSOILS II. Laboratory reference materials for soil-related studies. Eds. Gawlik B M and H Muntau. Joint Research Centre, European Commission, pp. 57–78.
Wenzel W W, Adriano D C, Salt D and Smith R 1999 Phytoremediation: A plant-microbe-based system. In Bioremediation of Contaminated Soils. Eds. D C Adriano, J-M Bollag, W T Frankenberger Jr. and R C Sims. pp. 457–510. SSSA Special Monograph no. 37, Madison, WI. 772 pp.
Wenzel W W, Puschenreiter M and Horak O 2000 Role and manipulation of the rhizosphere in soil remediation/revegetationIn Proceedings of SoilRem 2000 (International Conference of Soil Remediation), October 15– 19, 2000, Hangzhou, China, pp. 166–168.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Wenzel, W.W., Unterbrunner, R., Sommer, P. et al. Chelate-assisted phytoextraction using canola (Brassica napus L.) in outdoors pot and lysimeter experiments. Plant and Soil 249, 83–96 (2003). https://doi.org/10.1023/A:1022516929239
Issue Date:
DOI: https://doi.org/10.1023/A:1022516929239