Arsenic geochemistry and mineralogy as a function of particle-size in naturally arsenic-enriched soils.

Naturally arsenic (As) enriched agricultural soils represent a significant global human health risk. In this study, As fractionation and mineralogy were investigated in naturally As-enriched agricultural soils and their corresponding sand, silt and clay fractions. Median As increased generally in the order (mg/kg)∶ silt (280) < bulk (314) < sand (323)