Abstract
Sheep on the island of North Ronaldsay (Orkney, UK) feed mostly on seaweed, which contains high concentrations of dimethylated arsenoribosides. Wool of these sheep contains dimethylated, monomethylated and inorganic arsenic, in addition to unidentified arsenic species in unbound and complexed form. Chromatographic techniques using different separation mechanisms and detectors enabled us to identify five arsenic species in water extracts of wool. The wool contained 5.2 +/- 2.3 mug arsenic per gram wool. About 80% of the arsenic in wool was extracted by boiling the wool with water. The main species is dimethylarsenic, which accounted for about 75 to 85%, monomethylated arsenic at about 5% and the rest is inorganic arsenic. Depending on the separation method and condition, the chromatographic recovery of arsenic species was between 45% for the anion exchange column, 68% for the size exclusion chromatography (SEC) and 82% for the cation exchange column. The SEC revealed the occurrence of two unknown arsenic compounds, of which one was probably a high molecular mass species. Since chromatographic recovery can be improved by either treating the extract with CuCl/HCl (CAT: 90%) or longer storage of the sample (CAT: 105%), in particular for methylated arsenic species, it can be assumed that labile arsenic-protein-like coordination species occur in the extract, which cannot be speciated with conventional chromatographic methods. It is clear from our study of sheep wool that there can be different kinds of 'hidden' arsenic in biological matrices, depending on the extraction, separation and detection methods used. Hidden species can be defined as species that are not recordable by the detection system, not extractable or do not elute from chromatographic columns. Copyright (C) 2003 John Wiley Sons, Ltd.
| Original language | English |
|---|---|
| Pages (from-to) | 684-692 |
| Number of pages | 8 |
| Journal | Applied Organometallic Chemistry |
| Volume | 17 |
| Issue number | 9 |
| DOIs | |
| Publication status | Published - 2003 |
Keywords
- arsenic
- sheep
- seaweed
- analysis
- methyl arsenic
- wool extract
- ANION-EXCHANGE COLUMN
- DIMETHYLARSINIC ACID
- METHYLARSONIC ACID
- SPECIATION
- ARSENOSUGARS
- METABOLISM
Cite this
Identification of arsenic species in sheep-wool extracts by different chromatographic methods. / Raab, Andrea; Genney, David R; Meharg, Andrew Alexander; Feldmann, Jörg.
In: Applied Organometallic Chemistry, Vol. 17, No. 9, 2003, p. 684-692.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Identification of arsenic species in sheep-wool extracts by different chromatographic methods
AU - Raab, Andrea
AU - Genney, David R
AU - Meharg, Andrew Alexander
AU - Feldmann, Jörg
PY - 2003
Y1 - 2003
N2 - Sheep on the island of North Ronaldsay (Orkney, UK) feed mostly on seaweed, which contains high concentrations of dimethylated arsenoribosides. Wool of these sheep contains dimethylated, monomethylated and inorganic arsenic, in addition to unidentified arsenic species in unbound and complexed form. Chromatographic techniques using different separation mechanisms and detectors enabled us to identify five arsenic species in water extracts of wool. The wool contained 5.2 +/- 2.3 mug arsenic per gram wool. About 80% of the arsenic in wool was extracted by boiling the wool with water. The main species is dimethylarsenic, which accounted for about 75 to 85%, monomethylated arsenic at about 5% and the rest is inorganic arsenic. Depending on the separation method and condition, the chromatographic recovery of arsenic species was between 45% for the anion exchange column, 68% for the size exclusion chromatography (SEC) and 82% for the cation exchange column. The SEC revealed the occurrence of two unknown arsenic compounds, of which one was probably a high molecular mass species. Since chromatographic recovery can be improved by either treating the extract with CuCl/HCl (CAT: 90%) or longer storage of the sample (CAT: 105%), in particular for methylated arsenic species, it can be assumed that labile arsenic-protein-like coordination species occur in the extract, which cannot be speciated with conventional chromatographic methods. It is clear from our study of sheep wool that there can be different kinds of 'hidden' arsenic in biological matrices, depending on the extraction, separation and detection methods used. Hidden species can be defined as species that are not recordable by the detection system, not extractable or do not elute from chromatographic columns. Copyright (C) 2003 John Wiley Sons, Ltd.
AB - Sheep on the island of North Ronaldsay (Orkney, UK) feed mostly on seaweed, which contains high concentrations of dimethylated arsenoribosides. Wool of these sheep contains dimethylated, monomethylated and inorganic arsenic, in addition to unidentified arsenic species in unbound and complexed form. Chromatographic techniques using different separation mechanisms and detectors enabled us to identify five arsenic species in water extracts of wool. The wool contained 5.2 +/- 2.3 mug arsenic per gram wool. About 80% of the arsenic in wool was extracted by boiling the wool with water. The main species is dimethylarsenic, which accounted for about 75 to 85%, monomethylated arsenic at about 5% and the rest is inorganic arsenic. Depending on the separation method and condition, the chromatographic recovery of arsenic species was between 45% for the anion exchange column, 68% for the size exclusion chromatography (SEC) and 82% for the cation exchange column. The SEC revealed the occurrence of two unknown arsenic compounds, of which one was probably a high molecular mass species. Since chromatographic recovery can be improved by either treating the extract with CuCl/HCl (CAT: 90%) or longer storage of the sample (CAT: 105%), in particular for methylated arsenic species, it can be assumed that labile arsenic-protein-like coordination species occur in the extract, which cannot be speciated with conventional chromatographic methods. It is clear from our study of sheep wool that there can be different kinds of 'hidden' arsenic in biological matrices, depending on the extraction, separation and detection methods used. Hidden species can be defined as species that are not recordable by the detection system, not extractable or do not elute from chromatographic columns. Copyright (C) 2003 John Wiley Sons, Ltd.
KW - arsenic
KW - sheep
KW - seaweed
KW - analysis
KW - methyl arsenic
KW - wool extract
KW - ANION-EXCHANGE COLUMN
KW - DIMETHYLARSINIC ACID
KW - METHYLARSONIC ACID
KW - SPECIATION
KW - ARSENOSUGARS
KW - METABOLISM
U2 - 10.1002/aoc.488
DO - 10.1002/aoc.488
M3 - Article
VL - 17
SP - 684
EP - 692
JO - Applied Organometallic Chemistry
JF - Applied Organometallic Chemistry
SN - 0268-2605
IS - 9
ER -