Arsenic speciation in environmental samples

The growing importance of arsenic speciation analysis has led to development of wide range of analytical separation methodologies for extraction, separation, and identification or various arsenic compounds. This mini review describes the recent analytical progress in extraction and identification of different arsenic species in various environmental materials i.e., sediments, soils as well as food including vegetables, fruits, and marine biological samples. The techniques of separation, detection, extraction are discussed. Ion exchange or ion-pair chromatography in combination with element specific detection was widely used for arsenic speciation analysis. The reported detection limits (LOD's) using various analytical techniques were in the range of 0.02-20 mug kg(-1). Extraction techniques such as soxhlet, accelerated solvent, super-critical fluid, microwave assisted, etc., were proposed for arsenic extraction. The low power microwave assisted extraction is shown to be mild and fastest. About two dozen arsenic compounds were reported in various environmental samples including many unidentified arsenic species.