Characterization and Mobilization of Arsenic in Various Contaminated Materials

Abstract

Arsenic is a potentially toxic contaminant of concern even at relatively low concentrations in the environment. The complex chemistry of arsenic in the environment is influenced by a variety of chemical and physical factors. The presence of iron minerals is believed to be particularly important to arsenic mobility. Extraction methods were used to evaluate arsenic and iron in a variety of contaminated materials including mine tailings and soils. The contaminated materials were also evaluated for arsenic mobilization in batch experiments while pH and redox potential were monitored. A relationship between arsenic and iron was observed to occur in most, but not all, of the arsenic-contaminated samples. The most mobile fractions of arsenic were shown to be highly correlated with a simulated human oral bioavailable extraction method in the samples evaluated. The mobilization of arsenic by the simulated bioavailable extraction method was associated with a negligible mobilization of iron.