TY - JOUR

T1 - Electroanalytical and chromatographic determination of pentachlorophenol and related molecules in a contaminated soil

T2 - A real case example

AU - Codognoto, L.

AU - Zuin, V. G.

AU - De Souza, D.

AU - Yariwake, J. H.

AU - Machado, S. A.S.

AU - Avaca, L. A.

N1 - Funding Information: The authors wish to thank FAPESP and CNPq, Brazil, for scholarships and financial support to this work and to Eng. W. Haenni from CSEM, Switzerland, for providing the BDD electrode.

PY - 2004/8/1

Y1 - 2004/8/1

N2 - Electroanalytical and chromatographic methodologies have been applied for the determination of pentachlorophenol (PCP) and some of its derivatives in real soil samples contaminated by industrial discharge. The analytes were extracted with hexane from soil samples collected at different points of the site and mixed to produce a representative sample. Square wave voltammetry (SWV) experiments were carried out on either a boron-doped diamond (BDD) electrode or a gold ultramicroelectrode (Au-UME) in an analyte composed by the Britton-Robinson (B-R) buffer at pH 5.5 with the direct addition of proper amounts of the extract. The voltammetric responses revealed an irreversible anodic peak at approximately 0.80 V vs. Ag/AgCl with a peak current showing a linear dependence on PCP concentration. This linear relationship yielded a detection limit (DL) of 2×10-8 mol l-1 (or 5.5 μg l-1) for the BDD electrode and 6.9×10-8 mol l -1 (18.4 μg l-1) for the Au-UME, while the independently measured HPLC detection limit was 1.1×10-8 mol l-1 (3.0 μg l-1). The application of electroanalytical and chromatographic methodologies in the analysis of soil extracts revealed, besides the PCP responses, signals for some related molecules such as o-tetrachlorobenzoquinone (o-chloranil), hexachlorobenzene and tetrachlorophenol. Recovering experiments for PCP showed a concentration of 27.5 mg kg-1 for the electroanalytical determinations and 26.8 mg kg -1 for the HPLC analysis, values exceedingly high if considering that the maximum residue limit established for natural waters by the Brazilian Environmental Agency is 10 μg l-1.

AB - Electroanalytical and chromatographic methodologies have been applied for the determination of pentachlorophenol (PCP) and some of its derivatives in real soil samples contaminated by industrial discharge. The analytes were extracted with hexane from soil samples collected at different points of the site and mixed to produce a representative sample. Square wave voltammetry (SWV) experiments were carried out on either a boron-doped diamond (BDD) electrode or a gold ultramicroelectrode (Au-UME) in an analyte composed by the Britton-Robinson (B-R) buffer at pH 5.5 with the direct addition of proper amounts of the extract. The voltammetric responses revealed an irreversible anodic peak at approximately 0.80 V vs. Ag/AgCl with a peak current showing a linear dependence on PCP concentration. This linear relationship yielded a detection limit (DL) of 2×10-8 mol l-1 (or 5.5 μg l-1) for the BDD electrode and 6.9×10-8 mol l -1 (18.4 μg l-1) for the Au-UME, while the independently measured HPLC detection limit was 1.1×10-8 mol l-1 (3.0 μg l-1). The application of electroanalytical and chromatographic methodologies in the analysis of soil extracts revealed, besides the PCP responses, signals for some related molecules such as o-tetrachlorobenzoquinone (o-chloranil), hexachlorobenzene and tetrachlorophenol. Recovering experiments for PCP showed a concentration of 27.5 mg kg-1 for the electroanalytical determinations and 26.8 mg kg -1 for the HPLC analysis, values exceedingly high if considering that the maximum residue limit established for natural waters by the Brazilian Environmental Agency is 10 μg l-1.

KW - Diamond electrodes

KW - Electroanalysis

KW - Liquid chromatography

KW - Pentachlorophenol

KW - Soil contamination

KW - Ultramicroelectrodes

KW - Chemistry

UR - http://www.scopus.com/inward/record.url?scp=3042692445&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/3794b30b-1c2d-3c5c-b0f3-5463134b8194/

U2 - 10.1016/j.microc.2004.02.011

DO - 10.1016/j.microc.2004.02.011

M3 - Journal articles

AN - SCOPUS:3042692445

VL - 77

SP - 177

EP - 184

JO - Microchemical Journal

JF - Microchemical Journal

SN - 0026-265X

IS - 2

ER -