Arsenic-speciation in arsenate resistant and non-resistant populations of the earthworm, Lumbricus rubellus

C. J. Langdon, Andrew Alexander Meharg, Jorg Feldmann, T. Balgar, J. Charnocvk, M. Farquhar, T. G. Piearce, K. T. Semple

Research output: Contribution to journalArticle

60 Citations (Scopus)

Abstract

Arsenic speciation was determined in Lumbricus rubellus Hoffmeister from arsenic-contaminated mine spoil sites and an uncontaminated site using HPLC-MS, HPLC-ICP-MS and XAS. It was previously demonstrated that L. rubellus from mine soils were more arsenate resistant than from the uncontaminated site and we wished to investigate if arsenic speciation had a role in this resistance. Earthworms from contaminated sites had considerably higher arsenic body burdens (maximum 1,358 mg As kg(-1)) compared to the uncontaminated site (maximum 13 mg As kg(-1)). The only organo-arsenic species found in methanol/water extracts for all earthworm populations was arsenobetaine, quantified using both HPLC-MS and HPLC-ICP-MS. Arsenobetaine concentrations were high in L. rubellus from the uncontaminated site when concentrations were expressed as a percentage of the total arsenic burden (23% mean), but earthworms from the contaminated sites with relatively low arsenic burdens also had these high levels of arsenobetaine (17% mean). As arsenic body burden increased, the percentage of arsenobetaine present decreased in a dose dependent manner, although its absolute concentration rose with increasing arsenic burden. The origin of this arsenobetaine is discussed. XAS analysis of arsenic mine L. rubellus showed that arsenic was primarily present as As(III) co-ordinated with sulfur (30% approx.), with some As(V) with oxygen (5%). Spectra for As( III) complexed with glutathione gave a very good fit to the spectra obtained for the earthworms, suggesting a role for sulfur co-ordination in arsenic metabolism at higher earthworm arsenic burdens. It is also possible that the disintegration of As( III)-S complexes may have taken place due to (a) processing of the sample, (b) storage of the extract or (c) HPLC anion exchange. HPLC-ICP-MS analysis of methanol extracts showed the presence of arsenite and arsenate, suggesting that these sulfur complexes disintegrate on extraction. The role of arsenic speciation in the resistance of L. rubellus to arsenate is considered.

Original languageEnglish
Pages (from-to)603-608
Number of pages5
JournalJournal of Environmental Monitoring
Volume4
DOIs
Publication statusPublished - 2002

Keywords

  • LIQUID-CHROMATOGRAPHY
  • MASS-SPECTROMETRY
  • GLUTATHIONE
  • REDUCTION
  • TOXICITY

Cite this

Arsenic-speciation in arsenate resistant and non-resistant populations of the earthworm, Lumbricus rubellus. / Langdon, C. J.; Meharg, Andrew Alexander; Feldmann, Jorg; Balgar, T.; Charnocvk, J.; Farquhar, M.; Piearce, T. G.; Semple, K. T.

In: Journal of Environmental Monitoring, Vol. 4, 2002, p. 603-608.

Research output: Contribution to journalArticle

Langdon, C. J. ; Meharg, Andrew Alexander ; Feldmann, Jorg ; Balgar, T. ; Charnocvk, J. ; Farquhar, M. ; Piearce, T. G. ; Semple, K. T. / Arsenic-speciation in arsenate resistant and non-resistant populations of the earthworm, Lumbricus rubellus. In: Journal of Environmental Monitoring. 2002 ; Vol. 4. pp. 603-608.
@article{fcc76dd816384ac394216fefd1897ce0,
title = "Arsenic-speciation in arsenate resistant and non-resistant populations of the earthworm, Lumbricus rubellus",
abstract = "Arsenic speciation was determined in Lumbricus rubellus Hoffmeister from arsenic-contaminated mine spoil sites and an uncontaminated site using HPLC-MS, HPLC-ICP-MS and XAS. It was previously demonstrated that L. rubellus from mine soils were more arsenate resistant than from the uncontaminated site and we wished to investigate if arsenic speciation had a role in this resistance. Earthworms from contaminated sites had considerably higher arsenic body burdens (maximum 1,358 mg As kg(-1)) compared to the uncontaminated site (maximum 13 mg As kg(-1)). The only organo-arsenic species found in methanol/water extracts for all earthworm populations was arsenobetaine, quantified using both HPLC-MS and HPLC-ICP-MS. Arsenobetaine concentrations were high in L. rubellus from the uncontaminated site when concentrations were expressed as a percentage of the total arsenic burden (23{\%} mean), but earthworms from the contaminated sites with relatively low arsenic burdens also had these high levels of arsenobetaine (17{\%} mean). As arsenic body burden increased, the percentage of arsenobetaine present decreased in a dose dependent manner, although its absolute concentration rose with increasing arsenic burden. The origin of this arsenobetaine is discussed. XAS analysis of arsenic mine L. rubellus showed that arsenic was primarily present as As(III) co-ordinated with sulfur (30{\%} approx.), with some As(V) with oxygen (5{\%}). Spectra for As( III) complexed with glutathione gave a very good fit to the spectra obtained for the earthworms, suggesting a role for sulfur co-ordination in arsenic metabolism at higher earthworm arsenic burdens. It is also possible that the disintegration of As( III)-S complexes may have taken place due to (a) processing of the sample, (b) storage of the extract or (c) HPLC anion exchange. HPLC-ICP-MS analysis of methanol extracts showed the presence of arsenite and arsenate, suggesting that these sulfur complexes disintegrate on extraction. The role of arsenic speciation in the resistance of L. rubellus to arsenate is considered.",
keywords = "LIQUID-CHROMATOGRAPHY, MASS-SPECTROMETRY, GLUTATHIONE, REDUCTION, TOXICITY",
author = "Langdon, {C. J.} and Meharg, {Andrew Alexander} and Jorg Feldmann and T. Balgar and J. Charnocvk and M. Farquhar and Piearce, {T. G.} and Semple, {K. T.}",
year = "2002",
doi = "10.1039/b201366p",
language = "English",
volume = "4",
pages = "603--608",
journal = "Journal of Environmental Monitoring",
issn = "1464-0325",
publisher = "Royal Society of Chemistry",

}

TY - JOUR

T1 - Arsenic-speciation in arsenate resistant and non-resistant populations of the earthworm, Lumbricus rubellus

AU - Langdon, C. J.

AU - Meharg, Andrew Alexander

AU - Feldmann, Jorg

AU - Balgar, T.

AU - Charnocvk, J.

AU - Farquhar, M.

AU - Piearce, T. G.

AU - Semple, K. T.

PY - 2002

Y1 - 2002

N2 - Arsenic speciation was determined in Lumbricus rubellus Hoffmeister from arsenic-contaminated mine spoil sites and an uncontaminated site using HPLC-MS, HPLC-ICP-MS and XAS. It was previously demonstrated that L. rubellus from mine soils were more arsenate resistant than from the uncontaminated site and we wished to investigate if arsenic speciation had a role in this resistance. Earthworms from contaminated sites had considerably higher arsenic body burdens (maximum 1,358 mg As kg(-1)) compared to the uncontaminated site (maximum 13 mg As kg(-1)). The only organo-arsenic species found in methanol/water extracts for all earthworm populations was arsenobetaine, quantified using both HPLC-MS and HPLC-ICP-MS. Arsenobetaine concentrations were high in L. rubellus from the uncontaminated site when concentrations were expressed as a percentage of the total arsenic burden (23% mean), but earthworms from the contaminated sites with relatively low arsenic burdens also had these high levels of arsenobetaine (17% mean). As arsenic body burden increased, the percentage of arsenobetaine present decreased in a dose dependent manner, although its absolute concentration rose with increasing arsenic burden. The origin of this arsenobetaine is discussed. XAS analysis of arsenic mine L. rubellus showed that arsenic was primarily present as As(III) co-ordinated with sulfur (30% approx.), with some As(V) with oxygen (5%). Spectra for As( III) complexed with glutathione gave a very good fit to the spectra obtained for the earthworms, suggesting a role for sulfur co-ordination in arsenic metabolism at higher earthworm arsenic burdens. It is also possible that the disintegration of As( III)-S complexes may have taken place due to (a) processing of the sample, (b) storage of the extract or (c) HPLC anion exchange. HPLC-ICP-MS analysis of methanol extracts showed the presence of arsenite and arsenate, suggesting that these sulfur complexes disintegrate on extraction. The role of arsenic speciation in the resistance of L. rubellus to arsenate is considered.

AB - Arsenic speciation was determined in Lumbricus rubellus Hoffmeister from arsenic-contaminated mine spoil sites and an uncontaminated site using HPLC-MS, HPLC-ICP-MS and XAS. It was previously demonstrated that L. rubellus from mine soils were more arsenate resistant than from the uncontaminated site and we wished to investigate if arsenic speciation had a role in this resistance. Earthworms from contaminated sites had considerably higher arsenic body burdens (maximum 1,358 mg As kg(-1)) compared to the uncontaminated site (maximum 13 mg As kg(-1)). The only organo-arsenic species found in methanol/water extracts for all earthworm populations was arsenobetaine, quantified using both HPLC-MS and HPLC-ICP-MS. Arsenobetaine concentrations were high in L. rubellus from the uncontaminated site when concentrations were expressed as a percentage of the total arsenic burden (23% mean), but earthworms from the contaminated sites with relatively low arsenic burdens also had these high levels of arsenobetaine (17% mean). As arsenic body burden increased, the percentage of arsenobetaine present decreased in a dose dependent manner, although its absolute concentration rose with increasing arsenic burden. The origin of this arsenobetaine is discussed. XAS analysis of arsenic mine L. rubellus showed that arsenic was primarily present as As(III) co-ordinated with sulfur (30% approx.), with some As(V) with oxygen (5%). Spectra for As( III) complexed with glutathione gave a very good fit to the spectra obtained for the earthworms, suggesting a role for sulfur co-ordination in arsenic metabolism at higher earthworm arsenic burdens. It is also possible that the disintegration of As( III)-S complexes may have taken place due to (a) processing of the sample, (b) storage of the extract or (c) HPLC anion exchange. HPLC-ICP-MS analysis of methanol extracts showed the presence of arsenite and arsenate, suggesting that these sulfur complexes disintegrate on extraction. The role of arsenic speciation in the resistance of L. rubellus to arsenate is considered.

KW - LIQUID-CHROMATOGRAPHY

KW - MASS-SPECTROMETRY

KW - GLUTATHIONE

KW - REDUCTION

KW - TOXICITY

U2 - 10.1039/b201366p

DO - 10.1039/b201366p

M3 - Article

VL - 4

SP - 603

EP - 608

JO - Journal of Environmental Monitoring

JF - Journal of Environmental Monitoring

SN - 1464-0325

ER -