An Overview of Arsenic Extraction and Speciation Techniques in Soil and Water

Arsenic toxicity and bioavailability are controlled by its chemical forms (e.g. exchangeable, sorbed on organic matter, Fe/Al bound pools and mineral phases) and oxidation states (As(III) and As(V)). High interest has been developed in measurement of arsenic species due to their hazardous nature. Little information is available on methods used for quantitative distribution of arsenic forms and species in contaminated soils and water. The aim of this article is to provide an understanding of available techniques for arsenic speciation and its extraction from soil. Various techniques used in arsenic speciation (spectrometric, chromatographic and voltammetric) are discussed. Research efforts are still needed to develop inexpensive, rapid, sensitive and reproducible methodologies for arsenic species capable of working in the low detection limits.