ABSTRACT
The monitoring of total toxicity of water is of great importance to guarantee the safety of drinking water and estimate the level of water pollution from multiple pollutants.Here, we reported an online equipment for monitoring toxicity of water, where in-site cultured microorganisms were used as the test organism and respiratory inhibition of microorganisms was regarded as the toxicity response.A three-electrode electrochemical detector was integrated in the equipment, where an array electrode composed of microsized Pt disks, a Ag/AgCl (3 mol/L KCl) electrode and a gold wire were used as the working, reference and counter electrodes, respectively.The average respiratory inhibition ratios obtained with this equipment for 5.0, 10.0, 20.0 mg/L 3,5-dichlorophenol (DCP) were 24.4%, 48.9% and 59.2%, respectively.The equipment was further used for continuous online monitoring of the total toxicity of underground water, and successfully showed the toxicity alarm when challenged randomly by toxicity samples containing 5.0 mg/L DCP.The present results suggested the good promise of the equipment in online monitoring of water total toxicity.