Dominguez-Garay, A. and A. Esteve-Nunez.
Bioelectrochemistry [Published online 17 Mar 2018 prior to print]

Microbial electrochemical systems can be set up in soil for the harvesting of energy from microbial metabolism (sediment microbial fuel cell) or the bioremediation of contaminated environments (microbial electroremediating cell, MERC). Early thinking was that these technologies must be located in flooded environments to assure ionic contact between anode and cathode; however, a new configuration has been developed that overcomes this limitation by integrating an out-of-soil cathodic chamber with a ceramic barrier such that a closed-circuit system can be achieved without flooding the soil. In addition to harvesting energy with this new configuration, the MERC configuration was used to restore an atrazine-contaminated soil as proof of concept of enhanced bioremediation. Results showed that >98% of the initially available atrazine was removed within 2 weeks with the MERC configuration, in contrast with a 58% removal obtained under natural conditions. Toxicological tests conducted using green algae, Salmonella typhimurium, and Sorghum saccharatum confirmed a dramatic decline in soil toxicity after bioelectrochemical treatment in contrast with the still-toxic soil under natural conditions. See additional information in Chapters 4 and 5 of A. Dominguez-Garay's thesis at https://ebuah.uah.es/dspace/handle/10017/26377.