Sequential extraction of heavy metals in soils irrigated with wastewater
- 1 May 1999
- journal article
- research article
- Published by Taylor & Francis in Communications in Soil Science and Plant Analysis
- Vol. 30 (9-10), 1507-1519
- https://doi.org/10.1080/00103629909370303
Abstract
Different chemical forms of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn) were determined in agricultural soils cultivated with lettuce and celery. These soils have been irrigated for several decades with nontreated wastewaters. The chemical forms of the metals were characterized by sequential extraction analysis in five steps, the extracting solutions of which contained 200 mg L‐1 nitrilotriacetic acid (NTA). The results showed that Cd, Pb, and Cu exhibited the highest values of extracted metal, and Cr exhibited the lowest value. Almost all of the metals in these soils are bound to iron oxides, followed by the metal complexed to organic matter. The form bound to manganese oxides is equally important to Co. Cadmium is the most mobile metal and its available forms account for 40% of the total extracted. When these metals were determined in plants, both shoots and roots, a greater concentration of Cr, Zn, and Cu was found in celery, and Cu, Ni, and Zn in lettuce, most of the metals being in roots. Only Cd and Co are similarly distributed in shoots and in roots. The relation between the metal contents in plants and the different fractions of the metal in soil was evaluated through linear correlations. Different results were obtained, the forms accounting for the metal in celery are those of the metal bound to iron oxides, while the metal content in lettuce would be related to the exchangeable, bound to manganese oxide, and carbonate forms.Keywords
This publication has 19 references indexed in Scilit:
- Comparison of two sequential extraction procedures for metal fractionation in sediment samplesAnalytica Chimica Acta, 1998
- Zinc speciation in phosphate‐affected soilsCommunications in Soil Science and Plant Analysis, 1997
- Relationship between copper speciation in sediments and bioaccumulation by marine bivalves of TaiwanEnvironmental Pollution, 1996
- Sequential extraction analysis of heavy metals using a chelating agent (NTA) to counteract resorptionEnvironmental Pollution, 1996
- Influence of sewage sludge application on soil properties and on the distribution and availability of heavy metal fractionsCommunications in Soil Science and Plant Analysis, 1995
- Evaluation of sequential extraction for speciation of trace metals in model soil containing natural minerals and humic acidAnalytical Chemistry, 1993
- Comparative evaluation of residual and total metal analyses in polluted soilsCommunications in Soil Science and Plant Analysis, 1988
- Effect of Sequence in Extraction of Trace Metals from SoilsSoil Science Society of America Journal, 1986
- Chemical Availability of Cadmium in Mississippi River SedimentJournal of Environmental Quality, 1981
- Sequential extraction procedure for the speciation of particulate trace metalsAnalytical Chemistry, 1979