HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Related articles in JEQ Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via ISI Web of Science (8) Citing Articles via Google Scholar Google Scholar Articles by Neculita, C.-M. Articles by Deschênes, L. Search for Related Content PubMed PubMed Citation Articles by Neculita, C.-M. Articles by Deschênes, L. Agricola Articles by Neculita, C.-M. Articles by Deschênes, L. Related Collections Toxic Trace Metals Heavy Metals Soil Pollution Soil Chemistry

TECHNICAL REPORTS

Heavy Metals in the Environment

Mercury Speciation in Highly Contaminated Soils from Chlor-Alkali Plants Using Chemical Extractions

^a Department of Civil, Geological and Mining Engineering, École Polytechnique de Montréal, P.O. Box 6079, Station Centre-ville, Montreal, QC, Canada H3C 3A7
^b NSERC Industrial Chair in Site Remediation and Management, Chemical Engineering Department, École Polytechnique de Montréal, P.O. Box 6079, Station Centre-ville, Montreal, QC, Canada H3C 3A7

^* Corresponding author (gerald.zagury{at}polymtl.ca)

Received for publication March 10, 2004. A four-step novel sequential extraction procedure (SEP) was developed to assess Hg fractionation and mobility in three highly contaminated soils from chlor-alkali plants (CAPs). The SEP was validated using a certified reference material (CRM) and pure Hg compounds. Total, volatile, and methyl Hg concentrations were also determined using single extractions. Mercury was separated into four fractions defined as water-soluble (F1), exchangeable (F2) (0.5 M NH₄Ac–EDTA and 1 M CaCl₂ were tested), organic (F3) (successive extractions with 0.2 M NaOH and CH₃COOH 4% [v/v]), and residual (F4) (HNO₃ + H₂SO₄ + HClO₄). The soil characterization revealed extremely contaminated (295 ± 18 to 11 500 ± 500 mg Hg kg^–1) coarse-grained sandy soils having an alkaline pH (7.9–9.1), high chloride concentrations (5–35 mg kg^–1), and very low organic carbon content (0.00–18.2 g kg^–1). Methyl Hg concentrations were low (0.2–19.3 µg kg^–1) in all soils. Sequential extractions indicated that the majority of the Hg was associated with the residual fraction (F4). In Soils 1 and 3, however, high percentages (88–98%) of the total Hg were present as volatile Hg. Therefore, in these two soils, a high proportion of volatile Hg was present in the residual fraction. The nonresidual fraction (F1 + F2 + F3) was most abundant in Soil 1 (14–42%), suggesting a higher availability of Hg in this soil. The developed and validated SEP was reproducible and efficient for highly contaminated samples. Recovery ranged between 93 and 98% for the CRM and 70 and 130% for the CAP-contaminated soils.

Abbreviations: CAP, chlor-alkali plant • CRM, certified reference material • F1, water-soluble fraction • F2, exchangeable fraction • F3, organic fraction • F4, residual fraction • SEP, sequential extraction procedure

Related articles in JEQ:

This Issue in Journal of Environmental Quality

JEQ 2005 34: 1-6. [Full Text]