Dataset Information

Evaluating specificity of sequential extraction for chemical forms of lead in artificially-contaminated and field-contaminated soils.

ABSTRACT: In the present study, we evaluated a commonly employed modified Bureau Communautaire de Référence (BCR test) 3-step sequential extraction procedure for its ability to distinguish forms of solid-phase Pb in soils with different sources and histories of contamination. When the modified BCR test was applied to mineral soils spiked with three forms of Pb (pyromorphite, hydrocerussite and nitrate salt), the added Pb was highly susceptible to dissolution in the operationally-defined "reducible" or "oxide" fraction regardless of form. When three different materials (mineral soil, organic soil and goethite) were spiked with soluble Pb nitrate, the BCR sequential extraction profiles revealed that soil organic matter was capable of retaining Pb in more stable and acid-resistant forms than silicate clay minerals or goethite. However, the BCR sequential extraction for field-collected soils with known and different sources of Pb contamination was not sufficiently discriminatory in the dissolution of soil Pb phases to allow soil Pb forms to be "fingerprinted" by this method. It is concluded that standard sequential extraction procedures are probably not very useful in predicting lability and bioavailability of Pb in contaminated soils.

SUBMITTER: Tai Y

PROVIDER: S-EPMC4631023 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Evaluating specificity of sequential extraction for chemical forms of lead in artificially-contaminated and field-contaminated soils.

Tai Yiping Y McBride Murray B MB Li Zhian Z

Talanta 20130117

In the present study, we evaluated a commonly employed modified Bureau Communautaire de Référence (BCR test) 3-step sequential extraction procedure for its ability to distinguish forms of solid-phase Pb in soils with different sources and histories of contamination. When the modified BCR test was applied to mineral soils spiked with three forms of Pb (pyromorphite, hydrocerussite and nitrate salt), the added Pb was highly susceptible to dissolution in the operationally-defined "reducible" or "ox ...[more]

PMID: 23598210

Similar Datasets

Project description:The solidification/stabilization (S/S) method is the usual technique for the remediation of soils polluted by heavy metal in recent years. However, freeze-thaw cycles, an important physical process producing weathering of materials, will affect the long-term stability of engineering characteristics in solidified contaminated soil. In addition, it is still questionable whether using large dosages of binders can enhance the engineering properties of solidified/stabilized contaminated soils. In this study, the three most commonly used binders (i.e., cement, quicklime, and fly ash), alone and mixed in different ratios, were thus added to lead-contaminated soil in various dosages, making a series of cured lead-contaminated soils with different dosages of binders. Afterward, unconfined compression strength tests, direct shear tests, and permeability tests were employed on the resulting samples to find the unconfined compressive strength (UCS), secant modulus ( E 50 ), internal friction angle ( ? ), cohesion ( c ), and permeability coefficient ( k ) of each solidified/stabilized lead-contaminated soil after 0, 3, 7, and 14 days of freeze-thaw cycles. This procedure was aimed at evaluating the influence of freeze-thaw cycle and binder dosage on engineering properties of solidified/stabilized lead-contaminated soils. Results of our experiments showed that cement/quicklime/fly ash could remediate lead-contaminated soils. However, it did not mean that the more the dosage of binder, the better the curing effect. There was a critical dosage. Excessive cementation of contaminated soils caused by too much binder would result in loss of strength and an increase in permeability. Furthermore, it was found that UCS,   E 50 , ? , c , and k values generally decreased with the increase in freeze-thaw cycle time-a deterioration effect on the engineering characteristics of solidified lead-contaminated soils. Avoiding excessive cementation, 2.5% cement or quicklime was favorable for the value of E 50 while a 2.5% fly ash additive was beneficial for the k value. It is also suggested that if the freeze-thaw cycle continues beyond the period supported by excessive cementation, such a cycle will rapidly destroy the original structure of the soil and create large cracks, leading to an increase in permeability. The results also showed that the contaminated soils with a larger dosage of binders exhibited more significant deterioration during freeze-thaw cycles.

Dataset Information

Evaluating specificity of sequential extraction for chemical forms of lead in artificially-contaminated and field-contaminated soils.

Publications

Evaluating specificity of sequential extraction for chemical forms of lead in artificially-contaminated and field-contaminated soils.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets