Voltammetric Study of Arsenic (III) and Arsenic (V) in Ground Water of Hajigonj and Kalkini in Bangladesh

Abstract

The speciation of arsenic in groundwater samples using Square Wave Anodic Stripping Voltammetry (SWASV), Differential Pulse Anodic Stripping Voltammetry (DPASV) and Normal Pulse Anodic Stripping Voltammetry (NPASV) are described. Good resolution of the species, arsenic (III) and arsenic (V) is achieved using SWASV. The reliability of the methods was checked by analyzing the total arsenic content of the samples by Hydride Generation Atomic Absorptioion Spectrophotometer and by analyzing prepared controlled laboratory standard solution. Since this technique is comparatively cheaper than other available techniques it could be a better analytical technique for arsenic speciation from water. In this study, the assessment of inorganic arsenic species in ground water of Kalkini (Madaripur) and Hajigonj (Chandpur) is reported. It shows that arsenic content in water in different locations is irregular. Most of the locations contain higher level of As(III) than As(V). The highest concentration of arsenic is found in Anayetnagor (554.46 ± 0.07 μg/L) of Kalkini and Raichar (562 ± 0.50 μg/L) of Hajigonj. However, the level of total arsenic and As(III) of most of the villages of the study areas are more than the WHO guideline value (50μg/L). Therefore a proper monitoring process should be evolved along with the development of methods to keep the water free from arsenic.