Long Lifetime and High Reusability of Water Toxicity Determination Based on Electrochemically Active Bacteria

Abstract

Toxicity determination based on electrochemically active bacteria (EAB) shows great prospects for early warning of water pollution. However, the lifetime and reusability of EAB in toxicity determination remain uncertain. This study performed continuous toxicity determination by using an automatic water toxicity determination system based on EAB. Results demonstrated that EAB are capable of rapid responses to common heavy metal pollutants and make a full recovery after refreshment. Despite changes in microbial communities, EAB maintain a similar current generation capacity and toxicity sensitivity even after 20 continuous toxicity tests. The main reason for the stable performance was unchanged gene functions, as the toxicity tests did not result in a decrease in genes related to current generation or an increase in genes related to resistance. This study first reported that EAB possess a prolonged lifetime and good reusability in water toxicity determination, providing a basis for the continuous determination for water toxicity and the online monitoring of industrial wastewater toxicity based on EAB.