In recent years, there has been growing concern about antibiotic contamination in water bodies, particularly the widespread presence of fluoroquinolones (FQs), which pose a serious threat to ecosystems due to their extensive use and the phenomenon of “pseudo-persistence”. This article provides a comprehensive review of the literature on FQs in water bodies, summarizing and analyzing contamination levels of FQs in global surface water over the past three years, as well as the bioaccumulation and metabolism patterns of FQs in aquatic organisms, their ecological toxicity, and the influencing factors. The results show that FQs contamination is widespread in surface water across the surveyed 32 countries, with ciprofloxacin and norfloxacin being the most heavy contaminants. Furthermore, contamination levels are generally higher in developing and developed countries. It has been observed that compound types, species, and environmental factors influence the bioaccumulation, metabolism, and toxicity of FQs in aquatic organisms. FQs tend to accumulate more in organisms with higher lipid content, and toxicity experiments have shown that FQs exhibit the highest toxicity to bacteria and the weakest toxicity to mollusk. This article summarizes and analyzes the current research status and shortcomings of FQs, providing guidance and theoretical support for future research directions.

The extensive use of antibiotics has resulted in the generation and accumulation of antibiotic resistance genes (ARGs) in the environment, and domestic wastewater is one of the main reservoirs of ARGs and resistant bacteria. In this study, Illumina high-throughput sequencing and network analysis were used to study the microbial community characteristics, ARGs’ occurrence status, and resistance mechanism in the influent and effluent of a domestic sewage treatment plant in Changchun, China. A total of 29 phyla were found in the influent and effluent, including 23 bacterial phyla, 3 archaeal phyla, and 3 eukaryotic phyla. In total, 112 ARG subtypes were detected in the samples, and the dominant ARG subtypes were Erm(35) and tet(W/N/W). In this study, ARGs related to tetracycline and macrolide accounted for a high proportion, and the resistance mechanisms of ARGs detected in the samples were mainly antibiotic inactivation and antibiotic efflux pumps. Co-occurrence maps of ARGs and microbes demonstrated by network analysis indicated that the resistance genes kdpE, GES-5, and tetX may easily bind to microbes, potentially making them antibiotic-resistant bacteria. Fifty-seven bacteria in the genera Cupriavidus, Escherichia, and Collinsell are potential hosts of multiple ARGs. The findings can increase our understanding of the distribution of ARGs and their association with microbes in wastewater treatment plants, and also provide a research foundation for controlling the diffusion of ARGs in the environment.

This study aimed to investigate the levels of 12 sulfonamide antibiotics in freshwater fish species obtained from three cities in northeastern China (Harbin, Changchun, and Shenyang). The analysis was conducted using HPLC–MS/MS to accurately quantify the antibiotic concentrations in the fish samples. The results showed that the average levels of sulfonamide antibiotics in fish samples from Harbin, Changchun, and Shenyang were 1.83 ng/g ww, 0.98 ng/g ww, and 1.60 ng/g ww, respectively. Sulfamethoxazole displayed the highest levels and detection rates in all three cities, whereas sulphapyridine exhibited the lowest concentrations in all the fish samples. The levels of sulfonamide antibiotic residues in the different fish species varied widely among the cities, and the highest level of antibiotic residues was found in the muscle of carnivorous fish. The results from a health risk evaluation on the consumption of these fish indicated that the risk from long-term antibiotic exposure to local residents from the intake of the sampled fish was small and not sufficient to pose a significant health risk to consumers.

In order to better grasp the development and trends of tannery wastewater (TWW) treatment research, this paper provides a review of the TWW treatment research dynamics based on the Web of Science (WoS) database and using CiteSpace software. The research dynamics, hot topics, evolutionary history and research trends in this field are revealed. The results showed that research related to TWW treatment has shown a high growth trend in the number of articles in recent years, and India was outstanding in terms of influence in this area. The keyword clustering analysis showed that the main research hotspots in the field of TWW treatment were biological treatment processes (phytoremediation, constructed wetlands, anaerobic treatment and biofilm reactors) and chemical treatment processes (coagulation and flocculation, and advanced oxidation processes). The analysis of new research frontiers showed that the bioremediation and the application of biofuel cells in TWW will become important research directions in the future.