College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China.
Nanjing Foreign Language School, Nanjing, 210095, China.
Chemosphere. 2022 Mar;291(Pt 1):132681. doi: 10.1016/j.chemosphere.2021.132681. Epub 2021 Oct 27.
The individual and combined effects of tetracycline (TC) and divalent copper (Cu) on the performance of activated sludge systems and the abundances of tetracycline resistance genes (TRGs) in activated sludge, under both aerobic and anaerobic conditions, were studied. Activated sludge systems received TC (0.2 mg L) and Cu (5 mg L) separately or jointly under either aerobic or anaerobic conditions. The addition of TC did not affect the performance of activated sludge systems and the addition of Cu and mixed TC/Cu inhibited biological phosphorus removal. The TC removal efficiencies in systems under aerobic and anaerobic conditions were 98.4%-99.7% and 96.8%-99.9%, respectively, and Cu promoted TC removal in activated sludge systems. The TC degradation product was 4-epitetracycline (ETC) in activated sludge systems under both aerobic and anaerobic conditions. The total relative abundances of TRGs (tetA, tetC, tetE, tetM, tetO, tetW, tetX and tetB(P)) in activated sludge showed opposite development trends under the two oxygen conditions and aerobic condition was beneficial to the attenuation of high-risk TRGs. The results of this study might improve evaluation of the combined effects of antibiotics and heavy metals on wastewater biological treatment systems.
本研究考察了在有氧和厌氧条件下，四环素（TC）和二价铜（Cu）单独及联合作用对活性污泥系统性能和活性污泥中四环素抗性基因（TRGs）丰度的影响。在有氧或厌氧条件下，向活性污泥系统中分别投加 TC（0.2mg/L）和 Cu（5mg/L），或同时投加 TC 和 Cu。投加 TC 并不影响活性污泥系统的性能，而投加 Cu 和混合 TC/Cu 则抑制了生物除磷。在有氧和厌氧条件下，系统中 TC 的去除效率分别为 98.4%-99.7%和 96.8%-99.9%，Cu 促进了活性污泥系统中 TC 的去除。在有氧和厌氧条件下，活性污泥系统中 TC 的降解产物均为 4-差向四环素（ETC）。在两种氧气条件下，活性污泥中 TRGs（tetA、tetC、tetE、tetM、tetO、tetW、tetX 和 tetB(P)）的总相对丰度表现出相反的发展趋势，有氧条件有利于衰减高风险的 TRGs。本研究结果可能有助于提高对抗生素和重金属对废水生物处理系统的联合作用的评估。
