Eco-toxicological impacts of industrial wastewater and the role of bio-electrochemical systems (BES) in remediation: a review

The eco-toxicological effects of industrial wastewater in different parts of the global ecosystem have been a prominent matter of concern over the last 20 years. To mitigate these effects, industrial wastewater should be pollutant-free, and as a result, different technologies, including conventional and non-conventional, have been introduced so far. Due to these technologies, conventional treatment technologies are uneconomical due to the high energy demand for removing industrial wastewater pollutants. So, with advancements in technology, non-conventional technologies, including bio-electrochemical systems (BES), have been introduced and have proven environmentally sustainable. BES combines biology and electrochemistry to produce bioenergy and degrade pollutants from industrial wastewater. BES consumes energy in the chemical bonds of industrial wastes to efficiently degrade the contaminants. Apart from that, BES faces some major challenges, including high capital costs and scalability. BES scale-up challenges include electrode conductivity, sub-optimal contact, and high internal resistance between electrodes. The global demand for microbial fuel cells (MFC) was $8.60 million in 2017 and grew at a compound yearly growth rate of 11.2%, with a projected increase to $22.38 million by 2026. Thus, this review focuses on the pollutant release mechanisms of different industries that cause eco-toxicity threats to human health and water bodies. In addition, this study extensively discussed the pollution remediation by BES and factors affecting BES-based remediation. Graphical abstract