Tian Yajun, Zhu Jianyu, Ying Chuhan, Luo Hongwei, Zhang Shoufeng, Zhang Liqiu, Li Renna, Li Jun
College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, 310014, China; College of Environment Science and Technology, Beijing Forestry University, Beijing, 100083, China.
Zhejiang University, 866 Yuhangtang Road, Zheda Road, Hangzhou, Zhejiang, 310058, China.
Chemosphere. 2023 Apr;320:137820. doi: 10.1016/j.chemosphere.2023.137820. Epub 2023 Feb 1.
Microplastics (MPs), antibiotics and microorganism ubiquitously coexist in aquatic environments. MPs inevitably undergo photoaging processes in aquatic environments, affecting the interactions between MPs and antibiotics and the antibiotic resistance of microorganism. In this study, the impact of photoaging processes of MPs on their adsorption behavior of tetracycline (TC) and related formation of antibiotic resistance were investigated. It was found that the photoaging processes significantly increased the adsorption capacity of TC onto MPs, with the Q increasing from 0.387 to 0.507 mg/g at 288 K and from 0.507 to 0.688 mg/g at 308 K. The site energy distribution (SED) analysis further confirmed that the enhanced adsorption capacity was attributed to more high-energy adsorption sites acquired from MPs photoaging processes. Moreover, the enhanced adsorption of TC further facilitated the formation of seven antibiotic resistance genes (i.e., tetA, tetB, tetC, tetD, tetE, tetG, tetK) when MPs adsorbed with TC was covered by biofilm. This study helps comprehensively understand the environmental behaviors of co-existing MPs, antibiotics and microorganisms, providing a theoretical basis for evaluating and mitigating their coexistence risks.
微塑料（MPs）、抗生素和微生物在水生环境中普遍共存。微塑料在水生环境中不可避免地会经历光老化过程，这会影响微塑料与抗生素之间的相互作用以及微生物的抗生素抗性。在本研究中，研究了微塑料的光老化过程对其四环素（TC）吸附行为及相关抗生素抗性形成的影响。研究发现，光老化过程显著提高了微塑料对TC的吸附能力，在288K时，Q值从0.387mg/g增加到0.507mg/g，在308K时从0.507mg/g增加到0.688mg/g。位点能量分布（SED）分析进一步证实，吸附能力的增强归因于微塑料光老化过程中获得了更多高能吸附位点。此外，当吸附有TC的微塑料被生物膜覆盖时，TC吸附的增强进一步促进了7种抗生素抗性基因（即tetA、tetB、tetC、tetD、tetE、tetG、tetK）的形成。本研究有助于全面了解共存的微塑料、抗生素和微生物的环境行为，为评估和降低它们的共存风险提供理论依据。
