Integration of SMFC-Based Biosensor in Constructed Wetland for Real Time Monitoring and Bioremediation of Heavy Metals Contaminated Waters

Water contaminated with heavy metals is one of the most serious environmental problems in the world. Their timely detection and removal are of key importance for human health and ecosystems. The possibility of simultaneous real-time monitoring and bioremediation of waters contaminated with heavy metals has been established. Constructed wetlands with integrated sediment microbial fuel cells have been proposed for this purpose. Water contaminated with heavy metals - copper, chromium, nickel and zinc - was examined using them. All studied water samples showed a sudden voltage peak (in the range from 150 to 200 mV) when the contaminant entered the cell and a gradual decrease in voltage corresponding to the decreasing of the contaminant’s concentration. Chromium ions were removed the fastest – for 28 hours. The soil played the role of a protective layer for the electroactive microorganisms in the anode area, adsorbing the heavy metals in its upper layer and ensuring the efficient operation of the system. The studies showed an increase in the concentration of heavy metals in the surface soil layer between 5 and 35 mg/kg.