umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Leachability of PCBs in soil and its pH and dissolved organic matter (DOM) dependency
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
(English)Manuscript (preprint) (Other academic)
Abstract [en]

The leachability of eleven selected PCBs from naturally aged soil (Västervik, Sweden) was investigated in relation to the composition and concentration of dissolved organic matter at different pH (2 to 9), using a pH static test with initial acid/base addition. The batch leaching tests were performed on 50 g aliquots of a PCBs contaminated soil at a liquid to solid ratio (L/S) of 10 L/Kg. The PCBs were analyzed by gas chromatography coupled with high resolution mass spectrometry (GC-HRMS). The composition and of dissolved organic matter (DOM) at different pH values was explored by FTIR spectroscopy. The correlation between the FTIR data obtained for DOM and the log Kd values of PCBs was explored by orthogonal projections to latent structures (OPLS).  The log Kd-values of all target PCBs decreased with increased pH values and the log Kd-values were highly correlated with the concentration of total organic carbon (TOC) in the leachates. For the lower chlorinated congener, PCB 28, this correlation was weaker. The variation of fractions of concentrations of mono-ortho to di-ortho PCBs (PCB 66 to PCB 52 and PCB 105 to PCB 101) indicated an influence of the ortho-chlorine atoms through pH effects on their leachability. The FTIR analysis of DOM showed that the least chlorinated and hydrophobic PCB congeners (i.e. PCB 28) might be associated with the hydrophilic fraction (i.e. carboxylic groups) of the DOM.

National Category
Chemical Sciences
Identifiers
URN: urn:nbn:se:umu:diva-68377OAI: oai:DiVA.org:umu-68377DiVA: diva2:616638
Available from: 2013-04-17 Created: 2013-04-17 Last updated: 2013-04-18
In thesis
1. Association of hydrophobic organic compounds to organic material in the soil system
Open this publication in new window or tab >>Association of hydrophobic organic compounds to organic material in the soil system
2013 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

Contaminated soils and sediments have been identified as significant secondary sources of organic contaminants.  Leaching tests may be useful tools to estimate the mobility of contaminants via the water phase and thereby the risk for groundwater and surface water contamination. The influence of soil composition (peat and clay content) on the leachability was investigated in batch leaching experiments for chemically diverse hydrophobic organic compounds (HOCs: PCP, PAHs, HCB, HCHs, PCBs, and TCDD/Fs). The above mentioned compounds were analyzed by both GC-LRMS (gas chromatography coupled with low resolution mass spectrometry (GC-HRMS) and GC-HRMS (gas chromatography coupled with high resolution mass spectrometry). Also the the leachability of eleven selected PCBs from naturally aged soil (Västervik, Sweden) was investigated in relation to the composition and concentration of dissolved organic matter at different pH (2 to 9), using a pH static test with initial acid/base addition. The the composition and of dissolved organic matter (DOM) at different pH values was explored by FTIR spectroscopy. The results were evaluated by orthogonal projections to latent structures (OPLS).

Generally, for all model compounds studies, the Kd-values showed a variability of 2-3 orders of magnitude depending on the matrix composition. The Kd-values of moderately hydrophobic compounds, (e.g. HCHs, PCP and Phe), were correlated mainly with the organic matter content of soil. For more hydrophobic compounds (e.g.BaA, HCB and PCB 47), the leachability decreased as the proportions of  OM and clay contents increased. The Kd-values of 1,3,6,8-TCDD and 1,3,6,8-TCDF were  positively correlated with peat content but negatively correlated with clay content, while for PCB 153 and PCB 155 the correlations were reversed. The log Kd-values of all target PCBs decreased with increased pH values and the log Kd-values were highly correlated with the concentration of total organic carbon (TOC) in the leachates. The FTIR analysis of DOM showed that the least chlorinated and hydrophobic PCB congeners (i.e. PCB 28) might be associated with the hydrophilic fraction (i.e. carboxylic groups) of DOM. Our study demonstrated how complex interaction between the organic matter, clay components, pH and DOC influences the leachability of HOCs in a compound-specific manner.

Place, publisher, year, edition, pages
Umeå: Umeå Universitet, 2013. 42 p.
Keyword
HOCs, Organic Matter, Clay, DOM
National Category
Other Chemistry Topics
Research subject
biology, Environmental Science
Identifiers
urn:nbn:se:umu:diva-68378 (URN)978-91-7459-594-9 (ISBN)
Presentation
2013-04-25, KBC-huset, KB3B1, Umeå Universitet, Umeå, 13:00 (English)
Supervisors
Available from: 2013-04-18 Created: 2013-04-17 Last updated: 2013-04-18Bibliographically approved

Open Access in DiVA

No full text

By organisation
Department of Chemistry
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 98 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf