Removal of biological effects of organic pollutants in municipal wastewater by a novel advanced oxidation system

The Advanced Oxidation System (AOS) is a novel electrochemical advanced oxidation process that effectively removes bacterial and organic contaminants from wastewater. However, potential formation of secondary oxidative species may pose additional hazards to aquatic organisms living in the receiving water affected by the post-treatment effluent. The effect of exposure to AOS treated water, especially the potential long-term effects on aquatic organisms, requires further investigation to demonstrate both efficacy and safety of this process. To examine the potential adverse effects of AOS treated water, three aquatic species, including daphnia, zebrafish, and rainbow trout, were exposed to treated and untreated municipal wastewater effluent (MWE) spiked with one of two model organic contaminants, benzo[a]pyrene (BaP) and 17 beta-estradiol (E2). The results indicated AOS treatment significantly reduced the adverse effects caused by exposure to MWE and model organic contaminants to baseline levels in daphnia (reduced fecundity), zebrafish embryo (elevated EROD activity), and rainbow trout (elevated plasma vitellogenin). The Ames test was also conducted to confirm the removal efficacy of carcino-genicity of BaP spiked in MWE. Overall, this study demonstrated that AOS treatment is a promising and environmentally friendly technology for wastewater treatment, remediation, and management.

Automated summary

The AOS system effectively removes bacterial and organic contaminants from wastewater but may generate secondary oxidative species that pose hazards to aquatic organisms. Exposure to AOS treated water and its long-term effects on aquatic organisms require further investigation. The study showed that AOS treatment significantly reduced adverse effects on aquatic species exposed to treated wastewater effluent and model organic contaminants.