[Mechanisms and Influencing Factors of Antibiotic Removal in Sewage Biological Treatment]

Antibiotic pollution in the environment is becoming increasingly serious, and the induced antibiotic resistance has become a major threat to human health. A literature review of the antibiotic concentration in the influent and effluent of many sewage treatment plants around the world has shown that current sewage treatment processes do not effectively remove antibiotics. Studies have shown that adsorption and biodegradation are the main ways of removing antibiotics from sewage. The mechanisms of adsorption and the different adsorption extents of diverse antibiotics were analyzed in this paper. Biodegradation of antibiotics in a biological sewage treatment process were analyzed in terms of biodegradability, degrading bacteria, and degradation products. The effects of the operation conditions of biological sewage treatment processes, such as hydraulic retention time, sludge retention time, temperature, and process selection (conventional activated sludge, membrane bioreactor, or biological nitrogen removal processes), on adsorption and biodegradation pathways as well as on the removal efficiency of antibiotics are also discussed. The effects of bacterial composition, growth substrate, and coexisting micro-pollutants on the fate of antibiotics in biological wastewater treatment require more in-depth research.