[Distribution Characteristics of Antibiotic Resistance Genes in Wastewater Treatment Plants]

Wastewater treatment plants (WWTPs) are regarded as the main source for antibiotic resistant genes (ARGs). To explore the features regarding the distribution of ARGs in wastewater with complicated composition in treatment plants, wastewater samples from a chemical industry park that produced antibiotics were selected. qPCR was applied to detect the type and abundance of ARGs in the wastewater flows from the WWTPs. The results indicated that 16 types of ARGs were detected from the wastewater from the WWTPs, among which sulfonamide resistance genes and tetracycline resistance genes were the dominant ARGs that appeared in the wastewater. Additionally, intI 1 was detected and its abundance was correlated with that of sulfonamide resistance genes. This indicated that intI 1 may promote the migration and transformation of sulfonamide resistance genes. The pharmaceutical factories in the park mainly synthesize macrolide antibiotics. Because of the selective pressure, the absolute abundance of ermB in the wastewater was much higher than that in the other industrial wastewater. The total ARGs decreased by 1.16 log via traditional biological treatment process, and the total ARGs decreased by 2.46 log via the Fenton process. The results showed that the removal effects of deep treatment processes on ARGs were better than that of biological treatment in this wastewater treatment process. Highly abundant and movable ARGs already exist in the water body, and their release from WWTPs without effective treatment poses high risks to the environment.