ABSTRACT
Arsenic is a metalloid that is widely distributed in the earth’s crust, and thus it is an element of concern given its toxicological signicance, even at low concentrations. Sources of arsenic in the environment can be natural or anthropogenic, since it occurs as a trace element in most rocks as well as in soil, water, and atmospheric dust. Once released into the environment, arsenic compounds reach water sources, such as rivers and groundwater systems, and subsequently food sources. Thus, it is important to develop technologies for the remediation of arsenic-contaminated sites. Recent years have seen a growth in the research on the use bioremediation for the removal of heavy metal ions from aqueous solutions. Bioremediation is based on the ability of certain biomolecules or types of biomass to bind to and concentrate selected ions or other molecules from contaminated media (soil, sediment, air, and water). The major advantages of the bioremediation technology are its effectiveness in reducing the concentration of heavy metal ions to very low levels and its use of inexpensive biosorbent materials. The main purpose of this chapter is to provide an update on the recent literature concerning the strategies available for arsenic bioremediation and to discuss critically their main advantages and weaknesses. The discussions herein are focused on the main biosorption processes involved in this type of treatment.
