Bioavailability of arsenic in agricultural soils under the influence of different soil properties

Abstract

The major arsenic contamination in soil is resulting from the application of contaminated irrigation groundwater, which may further enter into the food chain via dietary intake. The severity of arsenic contamination in soil is regulated by the total arsenic content and its bioavailability. The bioavailable fraction of arsenic in soil is measured as the most considerable fraction, while assessing the latent risk arising from it. Various soil properties and their interactions with soil arsenic would give a better understanding of its availability in soil. The study was carried out to look into different bioavailable fractions of arsenic in soil and their relationships with different soil properties in the arsenic-prone areas of West Bengal, India. The results showed that the bioavailable soil arsenic fractions were in the order of water soluble < weakly adsorbed < specifically adsorbed. The arsenic content in paddy soils was significantly (p < 0.05) influenced by bulk density, clay, pH, organic matter, available calcium, available phosphorus, and available sulfur contents in soil. Soil enzyme activities of dehydrogenase, hydrolase, and glucosidase were also positively regulating the soil arsenic content. The study provides a better understanding of the interaction between different soil properties and soil arsenic content for developing the site-specific soil arsenic remediation strategies.