Insight into the removal of tetracycline-resistant bacteria and resistance genes from mariculture wastewater by ultraviolet/persulfate advanced oxidation process
Yanan Zhang, Yangguo Zhao, Yangguo Zhao, Dexiang Yang, Yan Zhao, Yan Zhao
Abstract
The antibiotic resistant bacteria and resistance genes are frequently detected recently in mariculture wastewater, thus posing a severe threat to the marine ecological environment. In this study, ultraviolet/peroxysulfate (UV/PS) process was adopted to treat tetracycline resistance pollutants and the influence of the seawater components, especially halogen ions, on UV/PS performance was investigated. The results showed that UV/PS process completely inactivated tetracycline resistant bacteria (TRBs) in five minutes and effectively removed tetracycline resistance genes (TRGs) for 1.18-2.17 log of tetA, tetM and tetW from mariculture wastewater. UV irradiation played an important role in the removal of three TRGs, where SO4·− contributed partly to the removal of tetA, while the partial removal of tetM and tetW was ascribed to the matrix composition, especially Cl− in mariculture wastewater. Due to UV competition effect, tetracycline as organic matter impacted heavily on the removal of the three TRGs in UV treatment, but even not in UV/PS system. This study demonstrated that UV/PS is a new alternative process to effectively remove tetracycline resistance pollutants in mariculture wastewater.