Arsenic: behavior in the environment, plant uptake mechanisms and human health risks

Negative impacts caused by arsenic (As) in soils and waters have attracted public interest due to contamination of ecosystems and human populations dwelling in the vicinity of its generating sources. The main anthropogenic sources of such contamination result from the oxidation of sulfide residues containing arsenopyrite in piles of mining tailings and the leaching of soils with high background of As. This contamination presents serious consequences to the functional components of ecosystems. Through plant uptake, this element can enter the food chain and cause several health problems, even at low exposure (<10 mgL–1). Therefore, to reduce the environmental impacts caused by contamination of soil, watercourses, and groundwater, the use of phytotechnologies applicable to the remediation of contaminated environments have been highlighted. The objective was to describe the current state of research on As, focusing on plant behavior and risks to health and the environment. Phytoremediation is a promising technique to recover local sites contaminated by trace elements such as As. Unfortunately, few plant species have presented phytoremediation potential so far. In the relation between soil-plant-behavior of As and human health risk, studies should be directed to the discovery of species with remediation potential and to analysis on the interactions of As with Pb, Zn and Cd, naturally associated with secondary minerals. To this end, the mineralogy and stability of these minerals should be studied via X-ray diffraction and X-ray absorption spectroscopy, combined with bioaccessibility analyses