Concept Note on Method Development for Speciation and Measurement of Arsenic (As) in Its Valence States (As (III) and As (V)) in Solid and Semisolid Organic Environmental Samples

Abstract

Arsenic, a metalloid widely distributed in nature, is released into the environment from a wide range of sources. Its toxicity and carcinogenicity mainly result from its trivalent form rather than its pentavalent state. This makes the speciation and measurement of arsenic in its valence states extremely important for assessing potential health hazard. Arsenic speciation methods exist for natural water samples. However, for solid samples it is often the total arsenic content that is measured. This chapter lays out a concept note on method development for speciation and measurement of arsenic in its valence states (i.e., As (III) and As (V)) in solid and semisolid organic environmental samples. The concept is based on chemical extraction of As (III) and As (V) species through respective precipitation followed by their dissolution into solution phase, which could be measured through “high-performance liquid chromatography inductively coupled plasma mass spectrometry” (HPLC/ICP-MS). Experimental approaches and work plan on this concept have also been elaborated.