Electro-bioremediation of hydrophobic organic soil-contaminants: A review of fundamental interactions

In recent years, there has been increasing interest in employing electro-bioremediation, a hybrid technology of bioremediation and electrokinetics for the treatment of soil contaminated with hydrophobic organic compounds (HOC). Present electro-bioremediation approaches however mainly aim at pollutant extraction through transport over large distances and tend to neglect both the impact of direct current (DC) on organism–soil interactions and microscale HOC release rates. Accordingly, no data are available on bioavailability changes acting via DC-driven effects on organism–compound and organism–soil interactions. This is a serious gap of our current knowledge hampering the improvement of the electro-bioremediation methodology. This review establishes a conceptual framework of the various influences of DC on processes governing HOC-bioavailability in soil, in particular the DC influence on microbial physiology and the physico-chemistry of organism–soil and organism–compound interactions.