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Critical review perspective: elemental speciation analysis methods in environmental chemistry – moving towards methodological integration

Jörg Feldmann A F , Pascal Salaün B and Enzo Lombi C D E
+ Author Affiliations
- Author Affiliations

A University of Aberdeen, College of Physcial Sciences, Trace Element Speciation Laboratory Aberdeen (TESLA), AB24 3UE, Scotland, UK.

B University of Liverpool, Department of Earth and Ocean Sciences, Liverpool, L69 3GP, UK.

C University of Copenhagen, Faculty of Life Science, Department of Agriculture and Ecology, 1871 Frederiksberg C, Denmark.

D Centre for Environmental Risk Assessment and Remediation, University of South Australia, Building X, Mawson Lakes Campus, Mawson Lakes, SA 5095, Australia.

E CRC CARE, PO Box 486, Salisbury, SA 5106, Australia.

F Corresponding author. Email: j.feldmann@abdn.ac.uk




Jörg Feldmann received his Ph.D. in Environmental Analytical Chemistry at University of Essen (Germany). He is the recipient of the Prize of the University of Essen and the Feodor Lynen Award (Alexander von Humboldt Foundation). After two years at the University of British Columbia (Canada), he became lecturer in 1997 at the University of Aberdeen (Scotland), where he progressed to a Chair in 2004. He is a member of the Environmental Chemistry Advisory Board and has published more than 100 scientific papers mainly on element speciation analysis in environmental and biological systems. The main focus of his research is on the use of hyphenated techniques for elemental and molecular mass spectrometry.



Pascal Salaün is an analytical and environmental chemist interested in the physico-chemical processes influencing the biogeochemical cycling of trace elements. He is specialised in the development of electrochemical sensors for the detection and speciation of metals and metalloids in natural systems. Currently, his research focuses on the use of solid microelectrodes, their application for on-site/in-situ monitoring and complexation studies together with the development of metallic nanostructures for electroanalytical purposes. He obtained a 5 years research fellowship in 2007 focusing on arsenic speciation in fresh/marine waters and in biological systems.



Enzo Lombi received a Ph.D. in agricultural chemistry from the Catholic University of Piacenza, Italy. He held positions at the University of Agricultural Science in Vienna, at Rothamsted Research (UK), at CSIRO Land and Water in Adelaide and at the University of Copenhagen. At present he is Associate Professor at the University of South Australia and is Leader of the Prevention Technology Program of the Cooperative Research Centre for Contamination Research and Remediation of the Environment. His major research focus is on the biogeochemistry of trace elements with a special interest on synchrotron-based techniques for the investigation of biological and soil processes.

Environmental Chemistry 6(4) 275-289 https://doi.org/10.1071/EN09018
Submitted: 9 February 2009  Accepted: 25 May 2009   Published: 25 August 2009

Environmental context. Elemental speciation defines mobility, accumulation behaviour and toxicity of elements in the environment. Environmental processes are then modelled using species information. Hence, it is important for environmental chemists to rely on unequivocal, precise and accurate analytical data for the identification and quantification of elemental species.

Abstract. We review the application of speciation analysis used in environmental chemistry studies to gain information about the molecular diversity of elements in various environmental compartments. The review focuses on three major analytical methodologies: electrochemical, X-ray absorption spectroscopy, and methods that couple chromatography with mass spectrometric detection. In particular, the review aims to highlight the advantages and disadvantages of the three methods, and to demonstrate that both the chemistry of the element and the nature of the environmental compartment determine the choice of the preferred analytical technique. We demonstrate that these two factors can lead to technique-dependent shortcomings that contribute to the current gaps in knowledge of elemental speciation in the environment. In order to fill those gaps, multi-method approaches are urgently needed. Finally, we present a selection of recent studies that exhibit the potential to use complementary techniques to overcome method-dependent limitations in order to reduce ambiguities and to gain more confidence in the assignment of the molecular structure of elements in environmental samples.


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1 Although in this case not equivalent without naming the element or species; μg L–1 or ppb are commonly used in studies that utilise ICPMS or AAS as the main analytical technique, whereas studies that use electrochemical methods or molecular MS express concentrations in molarities.