Numerous concerns have been raised on endocrine disrupting chemicals (EDCs) due to their widespread occurrence in aquatic environment. EDCs might interact directly with one or more components of the endocrine system, thereby causing malfunction and health problems to organisms including humans. For instance, EDCs may cause cancerous tumors, birth defects, and other developmental disorders when exposed in the environment. Currently, advanced oxidation processes (AOPs) are the typical treatment practices to remove EDCs. Among all the AOPs, Ozone has been used to treat organic pollutants including EDCs for the past few decades. However, although ozonation is more effective than other AOPs, it is still incapable of removing all the EDCs and degradates. More importantly, more toxic degradates are likely to be produced after ozonation treatment, leading to higher risk to the environment. Therefore, the study aims to evaluate the performance of ozonation and assess the biological risk of EDCs and degradates by a combination of mass measurement and bioassay monitoring.  It is anticipated that the study would elucidate the potential biological risks of EDCs when treated with ozonation, contributing to protecting the environment and safeguarding the health of human beings.