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Analysis of Arsenic Species in Environmental Samples

Many analytical methods for determining arsenic in various forms in environmental samples have been developed in recent years. The main objective of this review article is the presentation and comparison of the three principal techniques for the determination arsenic compounds, namely: hydride generation (HG), voltammetry and chromatography (liquid chromatography including high-performance liquid chromatography (HPLC), and gas chromatography (GC). These techniques (with the exception of voltammetry) are usually coupled with numerous sensitive detectors, which gives almost unlimited possibilities for the identification of arsenic species in environmental samples. Unfortunately, every method has its own advantages and disadvantages, with the more sensitive techniques requiring complicated sample preparation involving extraction of one kind or another to concentrate the sample and eliminate the effects of the background matrix of the sample. Speciation is the most important requirement for analysis in environmental research and HPLC is the most powerful method for arsenic species.