In situ microcosm remediation of polyaromatic hydrocarbons: efficiency and impacts of nanozerovalent iron and activated carbon

Nano Zero-Valent Iron (nZVI) and Activated Carbon (AC) addition is recently developed techniques applied for the remediation of sediments and aqueous solutions contaminated with hydrophobic organic compounds. However, an important point that must be underlined consists in the possible occurrence of eco(toxico)logical secondary effects, especially when applied in situ. In this study, we investigated AC and nZVI as remediation methods in contaminated water and sediment, evaluating also their possible negative impact on marine crustacean Artemia franciscana. The results showed that the AC and nZVI efficiency removal were similar for both sediment and seawater; and the survival of both nauplii and adults was mainly impacted by nZVI than by AC. At the molecular level, the nZVI-addition induced variations in the expression of stress and developmental genes. In conclusion, these data suggest potential ecotoxicological effects of nZVI and stress the need for a detailed further investigation of secondary effects of this technique.