Arsenic speciation of terrestrial invertebrates.
The distribution and chemical form (speciation) of arsenic in terrestrial food chains determines both the amount of arsenic available to higher organisms, and the toxicity of this metalloid in affected ecosystems. Invertebrates are part of complex terrestrial food webs. This paper provides arsenic concentrations and arsenic speciation profiles for eight orders of terrestrial invertebrates collected at three historical gold mine sites and one background site in Nova Scotia, Canada. Total arsenic concentrations, determined by inductively coupled plasma mass spectrometry (ICP-MS), were dependent upon the classification of invertebrate. Arsenic species were determined by high-performance liquid chromatography (HPLC) ICP-MS and X-ray absorption spectroscopy (XAS). Invertebrates were found by HPLC ICP-MS to contain predominantly arsenite and arsenate in methanol/water extracts, while XAS revealed that most arsenic is bound to sulfur in vivo. Examination of the spatial distribution of arsenic within an ant tissue highlighted the differences between exogenous and endogenous arsenic, as well as the extent to which arsenic is transformed upon ingestion. Similar arsenic speciation patterns for invertebrate groups were observed across sites. Trace amounts of arsenobetaine and arsenocholine were identified in slugs, ants, and spiders.
Moriarty
Maeve M
MM
Environmental Sciences Group, Royal Military College of Canada, P.O. Box 17000 Station Forces, Kingston, Ontario K7K 7B4, Canada.
Koch
Iris
I
Gordon
Robert A
RA
Reimer
Kenneth J
KJ
D000818:Animals; D001000:Ants / Q000187:drug effects; D001149:Arsenates / Q000737:chemistry; D001151:Arsenic / Q000633:toxicity*; D018053:Arsenites / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D020387:Food Chain; D049851:Gastropoda / Q000187:drug effects; D007448:Invertebrates / Q000187:drug effects; D013058:Mass Spectrometry / Q000379:methods; D000432:Methanol / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis; D013045:Species Specificity; D013052:Spectrometry, X-Ray Emission / Q000379:methods; D013112:Spiders / Q000187:drug effects; D014867:Water / Q000737:chemistry
D001149:Arsenates; D018053:Arsenites; D012989:Soil Pollutants; D014867:Water; C015001:arsenite; D001151:Arsenic; C025657:arsenic acid; D000432:Methanol