School of Environmental Science and Engineering, Yangzhou University, Yangzhou, 225127, China.
Key Laboratory of Coastal Environmental Process and Ecology Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences; Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, 264003, China.
Environ Sci Pollut Res Int. 2020 Nov;27(33):42104-42114. doi: 10.1007/s11356-020-10194-4. Epub 2020 Jul 24.
It is important to study the fate and transport of antibiotics in aquatic environments to reveal their pollution status. The premise behind fate and transport studies is to evaluate the reaction processes of the target antibiotics. However, available research on the environmental behaviors of antibiotics in certain natural waters, such as estuarine water, is scarce. In this study, single reactions such as sorption, biodegradation, and photolysis and multiple degradation reactions of sulfamethoxazole (SMX), trimethoprim (TMP), and ciprofloxacin (CIP) in the estuarine water were studied. The sorption rates of the target antibiotics in the estuarine water-sediment system were very fast, and the sorption amounts varied among sediments and antibiotics. Hydrolysis did not contribute to the degradation of the target antibiotics. Biodegradation had a low contribution to the degradation of the target antibiotics in the estuarine water. In comparison, photolysis was the dominant degradation process for SMX, TMP, and CIP. The rates of photolysis of the tested antibiotics in the estuarine water were greater than those in pure water; thereby, indicating photolysis of these antibiotics was more prone to occur in the estuarine water. In the multiple degradation experiments, it was found that there may be synergistic effects between the single degradation processes. Thus, the aqueous concentrations of antibiotics decreased rapidly by sorption after entering the estuarine water and then decreased relatively slowly by photolysis and biodegradation. This study provides information for evaluating the environmental behaviors of antibiotics in estuarine environments.
研究抗生素在水生环境中的归趋和迁移对于揭示其污染状况非常重要。归趋和迁移研究的前提是评估目标抗生素的反应过程。然而，对于某些天然水中（如河口水中）抗生素的环境行为，可用的研究还很少。在本研究中，研究了磺胺甲恶唑（SMX）、甲氧苄啶（TMP）和环丙沙星（CIP）在河口水中的单一反应（如吸附、生物降解和光解）和多种降解反应。目标抗生素在河口水-沉积物系统中的吸附速率非常快，并且吸附量在沉积物和抗生素之间有所不同。水解对目标抗生素的降解没有贡献。生物降解对河口水中目标抗生素的降解贡献较低。相比之下，光解是 SMX、TMP 和 CIP 的主要降解过程。测试抗生素在河口水中的光解速率大于在纯水中的光解速率；因此，表明这些抗生素在河口水中更容易发生光解。在多种降解实验中，发现单一降解过程之间可能存在协同作用。因此，抗生素进入河口水后，通过吸附迅速降低水相浓度，然后通过光解和生物降解缓慢降低。本研究为评估抗生素在河口环境中的环境行为提供了信息。
