Dispersing Pollutant‐Degrading Bacteria in Contaminated Soil without Touching it

Abstract

AbstractEngineered bioremediation of soil‐bound contaminants relies on the presence of contaminant‐degrading microorganisms, optimal physical and chemical conditions for their catabolic activity and the bioavailability of the contaminants, which is often achieved by homogenization of the contaminated matrix. Mechanical treatment of soil for the stimulation of bioremediation is energy inefficient, since it moves the entire soil matrix just to facilitate the encountering of minor masses of microbes and pollutants. Moreover, it is not feasible for the remediation of entire (mega‐)sites. In this review, methods and mechanisms are presented that are capable of dispersing catabolically active bacteria in soil and sediment without the need of ex‐situ treatment. A less energy‐consuming and hence environmentally sounder biotechnology is proposed that makes use of the effects of electrical current, bacterial chemotaxis and bioturbation through the activities of soil animals, plant roots and fungal mycelia, all leading to increased pollutant bioavailability.