Responses of electrochemically active bacteria to toxic pollutants and identification of sensitive species

Employing electrochemically active bacteria (EAB) as water-quality toxicity indicators enables real-time alerts during sudden contamination. Despite this advantage, the application of EAB-based early-warning systems remains limited by their relatively low sensitivity. Because EAB responses are largely determined by their toxicity tolerance, species with lower resistance are expected to be more sensitive. However, EAB species exhibiting heightened susceptibility to toxic pollutants have yet to be reported. This study analyzed how exposure to ten representative toxic pollutants at varying concentrations reshaped the community composition of a mixed EAB consortium. Exposure shifted community structure; specific genera declined sharply as pollutant levels increased, indicating potential high susceptibility. These susceptible genera responded consistently to other toxicants within the same pollutant class with high susceptibility. When compared with the widely used EAB model strain, the species in these genera improved toxicity determination sensitivity for their respective pollutant types.