Occurrence and toxicity of antibiotics in the aquatic environment: A review

Antibiotic-induced multi-trophic effects and their cascades in a sub-tropical freshwater ecosystem

Antibiotics are commonly detected in aquatic ecosystems worldwide due to their extensive use and excretion by humans and animals, posing potential risks to the health of these ecosystems. This study aimed to assess the ecological effects of the antibiotic ciprofloxacin on both structural (microbes, phytoplankton, zooplankton, and macroinvertebrates) and functional endpoints of a sub-tropical freshwater ecosystem. Ciprofloxacin was applied at concentrations of 0, 0.5, 5, 50, and 500 µg/L for 21 consecutive days in outdoor mesocosms, followed by a five-week recovery period. Ciprofloxacin significantly affected the structure of microbial, phytoplankton, and zooplankton communities, with calculated NOECs of 5, 0.5, and 5 µg/L, respectively. Notably, the microbial community composition, particularly taxa within the phyla Cyanobacteria and Bacteroidetes, exhibited marked shifts. Among phytoplankton, the filamentous cyanobacterium Cylindrospermopsis sp. exhibited the largest negative response to ciprofloxacin, while Microcystis sp. displayed the largest increase in abundance. Ciprofloxacin exposure also indirectly led to significant increases in zooplankton populations belonging to Cladocera, Copepoda, and Rotifera. Significant effects of ciprofloxacin on physicochemical parameters related to carbon and nitrogen cycling were observed. Structural equation models revealed that ciprofloxacin induced both direct and indirect effects across multiple trophic levels through cascading effects, further impacting ecosystem-level endpoints. Overall, this study provides an understanding of the potential ecological risks posed by antibiotic pollution on freshwater ecosystems.

Zebrafish embryos ecotoxicity traceability of pharmaceutical wastewater during simultaneous nitrification-denitrification process

Toxicity assessments based on transcriptomics and metabolomics at target organs are magnitude difference due to the tremendous variations in the sensitivity of receptor binding sites (subunits), which often require expensive instrumentation using quantitative whole-body autoradiography. In this study, zebrafish embryos combined with toxicity identification evaluation (TIE) and ECOSAR toxicity prediction were applied to monitor comprehensive toxicity changes of fermentation pharmaceutical wastewater (FPW) in the expanded granular sludge bed (EGSB) and the modified simultaneous nitrification-denitrification (SND) process. FPW with high toxicity (30.93 TU) was predominately detoxified (to 4.04 TU) in anaerobic EGSB process, in which chlortetracycline (CTC) was degraded via demethylation, dechlorination and ring-cleaving. TIE results showed that non-polar pollutants contributed to the major toxicity and existed in the whole process. The pH adjustment significantly influenced the toxicities of CTC and its mixture with NH4+-N (MCTC+NH4+) or NO2--N (MCTC+NO2-) due to the hydrolysis and chelation. Noticeably, nearly no nitrite/nitrate were accumulated in SND treatment process, which greatly alleviated the toxicities of MCTC+NH4+ and MCTC+NO2- due to no generation of free ammonia and free nitrous acid. MCTC+NH4+ exhibited antagonistic toxicity in all test pH, but MCTC+NO2- converted from synergistic (pH i) to antagonistic (pH 7.5). This study deepened the detoxification mechanistic interpretations of FPW in the modified EGSB-SND process as well as related toxicity variation information.

Simultaneous removal of cadmium and tetracycline from aqueous solutions by oxalic acid and pyrite co-modified biochar: Performance and mechanism

The remediation of combined contamination with heavy metals and antibiotics in soil and aqueous environments represents an ongoing challenge. In this study, a novel highly functionalized biochar-based composite (FeS2@OA-BC) was synthesised by combining oxalic acid (OA) pre-treatment with ball-milling of FeS2 for the simultaneous removal of cadmium (Cd2+) and tetracycline (TC) from aqueous solutions. FeS2@OA-BC demonstrated exceptional performance in simultaneously removing 74.7 % of Cd2+ and 95.8 % of TC from the binary systems, meanwhile the degradation rate of TC reached up to 64.8 %. Moreover, no significant competitive or promoting effects between Cd2+ and TC removal were observed by FeS2@OA-BC in binary systems. The adsorption of Cd2+ was primarily governed by three mechanisms: complexation with functional groups, Cd-π conjugation and cation exchange. Meanwhile, TC degradation relied on reactive oxygen species (ROS), where hydroxyl radicals (•OH) and hydrogen peroxide (H2O2) played dominant roles, with singlet oxygen (1O2) contributing minimally. The co-modification of OA and FeS2 synergistically introduces abundant exogenous defect sulphur vacancies (SVs), enhancing molecular oxygen activation and stimulating more ROS for TC degradation, as well as promoting more functional groups as adsorption sites for Cd2+ complexation. This therefore ultimately led to the reinforcement of the concurrent removal of Cd2+and TC. Overall, FeS2@OA-BC shows great promise for addressing combined pollution involving heavy metals and antibiotics in environmental systems.

Periodate activation for tetracycline degradation with MoS2/MnFe2O4 nanocomposite: Efficiency and Mechanistic insights

In this study, a MoS2/MnFe2O4 nanocomposite was employed as a periodate (PI) activator for the first time, aiming to synergistically degrade tetracycline (TC). Three different ratios of MoS2/MnFe2O4 nanocomposites were synthesized using a solvothermal method, among which MoS2/MnFe2O4-3 (MMF-3) exhibited the highest efficiency in TC degradation. At pH 4.65, PI concentration of 0.2 mM and MMF-3 dosage of 0.2 g/L, the removal rate of TC was 80.74 %. The potential reaction mechanism of the MMF-3/PI system was revealed, identifying IO•3, 1O2, and •OH as the primary reactive oxygen species (ROS) responsible for TC removal. Furthermore, the Mo(IV)/Mo(VI) cycle within the MoS2/MnFe2O4 composite significantly enhanced the Fe(II)/Fe(III) redox cycle, promoting ROS regeneration and thereby enabling the efficient degradation of TC. Two potential pathways for TC degradation were proposed, and the biotoxicity of the degradation process was assessed, demonstrating that the MMF-3/PI system is environmentally friendly and does not produce highly toxic byproducts. Additionally, Cl- and NO3- showed negligible effects on TC removal, while H2PO4- significantly inhibited the process, and humic acid enhanced it. Cycling experiments revealed consistent TC removal rates exceeding 70 % across four cycles, highlighting the stability and reusability of the MMF-3 material. The removal efficiency of TC was largely unaffected by various natural water conditions, underscoring the substantial practical potential of the MMF-3/PI system. Overall, the MMF-3/PI system offers a promising approach to mitigating antibiotic contamination in water bodies.

Host-specific assembly of phycosphere microbiome and enrichment of the associated antibiotic resistance genes: Integrating species of microalgae hosts, developmental stages and water contamination

Phytoplankton-bacteria interactions profoundly impact ecosystem function and biogeochemical cycling, while their substantial potential to carry and disseminate antibiotic resistance genes (ARGs) poses a significant threat to global One Health. However, the ecological paradigm behind the phycosphere assembly of microbiomes and the carrying antibiotic resistomes remains unclear. Our field investigation across various freshwater ecosystems revealed a substantial enrichment of bacteria and ARGs within microalgal niches. Taking account of the influence for species of microalgae hosts, their developmental stages and the stress of water pollution, we characterized the ecological processes governing phycosphere assembly of bacterial consortia and enrichment of the associated ARGs. By inoculating 6 axenic algal hosts with two distinct bacterial consortia from a natural river and the phycosphere of Scenedesmus acuminatus, we observed distinct phycosphere bacteria recruitment among different algal species, yet consistency within the same species. Notably, a convergent bacterial composition was established for the same algae species for two independent inoculations, demonstrating host specificity in phycosphere microbiome assembly. Host-specific signature was discernible as early as the algal lag phase and more pronounced as the algae developed, indicating species types of algae determined mutualism between the bacterial taxa and hosts. The bacteria community dominated the shaping of ARG profiles within the phycosphere and the host-specific phycosphere ARG enrichment was intensified with the algae development. The polluted water significantly stimulated host's directional selection on phycosphere bacterial consortia and increased the proliferation antibiotic resistome. These consortia manifested heightened beneficial functionality, enhancing microalgal adaptability to contamination stress.

Effects of antibiotics and metals on meiofauna assessed through taxon/functional and modeling tools: a case study of amoxicillin and copper

This research examines the impacts of amoxicillin and copper, separately and together, on the taxonomic and functional diversity of free-living marine nematodes. Sediment samples were gathered from the Jeddah shoreline in Saudi Arabia, and meiobenthic organisms were subjected to two concentrations of amoxicillin [550 and 1100 ng/L] and copper [130 mg/kg dry weight (dw) and 260 mg/kg dw] in microcosms for 30 days. The findings indicated a higher nematode tolerance than that of polychaetes, copepods, isopods, amphipods, and cumaceans. A notable decrease in both nematode species abundance and diversity was observed as contaminant levels rose, resulting in the reduction of sensitive bioindicators, specifically Paracanthonchus sadspitensis, Dorylaimopsis timmi, Cinctonema papillata, Eleutherolaimus obtusicaudatus, Terschellingia longicaudata, Theristus poloris, Halalaimus longicaudatus, Parodontophora breviseta, and Theristus pertenuis for copper, as well as C. papillata, T. longicaudata, H. longicaudatus, T. pertenuis, D. timmi, and Viscosia viscosia for amoxicillin. Conversely, tolerant/opportunistic species such as Metoncholaimus albidus for amoxicillin and Daptonema oxycerca for both copper and amoxicillin showed an increase in abundance. The pairing of amoxicillin and copper demonstrated a synergistic or additive toxic impact. Furthermore, pollution changed the functional characteristics of nematodes, leading to a rise in detritivore species with clavate tails, and a decline in microvore species with conical and filiform tails. A computational analysis also supported these findings by evaluating the toxicokinetics and molecular interactions of amoxicillin and copper.

Carbon nanomaterials for co-removal of antibiotics and heavy metals from water systems: An overview

Pollution resulting from the combination of antibiotics and heavy metals (HMs) poses a significant threat to human health and the natural environment. Adsorption is a promising technique for removing antibiotics and HMs owing to its low cost, simple procedures, and high adsorption capacity. In recent years, various novel carbon nanomaterials have been developed, demonstrating outstanding performance in simultaneously removing antibiotics and HMs. This work presents a comprehensive review of carbon nanomaterials (i.e., carbon nanotubes, graphene, resins, and other nanocomposites) for the co-removal of antibiotics and HMs in water systems. The mechanisms influencing the simultaneous removal of antibiotics and HMs include the bridging effect, electrostatic shielding, competition, and spatial site-blocking effects. These mechanisms can promote, inhibit, or have no impact on the adsorption capacity for antibiotics or HMs. Additionally, environmental factors such as pH, inorganic ions, natural organic matter, and microplastics affect the adsorption efficiency. This review also covers adsorbent regeneration and cost estimation. On the laboratory scale, the cost of the adsorption process primarily depends on the chemical and energy costs of adsorbent production. Our assessment highlights that the carbon-nanomaterial-mediated simultaneous removal of antibiotics and HMs warrants comprehensive consideration from both economic and environmental perspectives.

Antibiotics and endocrine disrupting chemicals in effluent from wastewater treatment plants of a mega-city affected the water quality of juvenile Chinese sturgeon habitat: Upgrades to wastewater treatment processes are needed

Antibiotics and endocrine-disrupting chemicals (EDCs) were measured near a juvenile Chinese sturgeon habitat (JCSH) in the Yangtze River Estuary. It was found that the concentrations in the wet season, when Chinese sturgeon are frequently detected in the habitat, were 146 ± 140 ng/L and 2.34 ± 1.50 ng/L. They posed a high/medium risk to algae and fish. Mega-cities surround the habitat. The largest one, Shanghai, discharges 1020 kg antibiotics and 42.3 kg EDCs to the waterbody near the habitat annually. Restrictions on antibiotic use and industrial restructuring cannot efficiently reduce these pollutants. Optimization of wastewater treatment processes regarding antibiotics and EDCs is necessary. To keep the effluent safe for algae and fish, the removal rate of the risky substances sulfonamides (SAs), fluoroquinolones (FQs), phenolic estrogens (PEs), and steroid estrogens (SEs) should be elevated to 77 %, 99 %, 99 %, and 89 %. Advanced oxidation or adsorption should be added to promote the environmental quality of the JCSH.

Fluoroquinolone ciprofloxacin removal from synthetic and real wastewaters by single and combined electrochemical advanced oxidation processes. A review

Ciprofloxacin (CIP) is a widely prescribed fluoroquinolone antibiotic detected in the aquatic environment fostering the emergence of bacteria and posing risks the human health and ecosystem integrity. The present comprehensive critical review deals with CIP removal from synthetic and real wastewater by electrochemical advanced oxidation processes (EAOPs) up to 2024. Lower performance was obtained in real wastewaters than synthetic ones because their components scavenged-generated oxidizing agents. Anodic oxidation (AO) has been developed with active dimensionally stable anodes (DSA) and the non-active potent boron-doped diamond (BDD) one, where CIP solutions in chloride medium reached a maximal of 75 % mineralization. A more rapid CIP degradation and up to 96 % mineralization have been found for homogeneous electro-Fenton (EF) with Pt and Fe2+ catalyst. Heterogeneous Fenton with functionalized iron cathodes and solid iron catalysts, and heterogeneous EF-like with non-ferrous catalysts gave worse results. Novel modified EF processes with dual cathodes for direct.•OH production after H2O2 electrogeneration allowed up to 96 % mineralization. Photoelectro-Fenton (PEF) with UVA light and solar PEF (SPEF) can yield overall mineralization by the rapid photolysis of final Fe(III)-carboxylate species formed. Photoelectrocatalysis (PEC) with new photoanodes like FTO/Ni-ZnO under UVA light yielded 87 % mineralization. Hybrid AO, EF, PEF, and PEC processes with persulfate, O3, ultrasounds, or photocatalysis were more powerful than their single EAOPs. The characteristics and performance of each method, the generation of oxidants (•OH, O2•-, and/or 1O2), its reusability, and the by-products produced are discussed. The loss of toxicity of the treated solutions by EAOPs is finally detailed.

Exposure to metoprolol and propranolol mixtures on biochemical, immunohistochemical, and molecular alterations in the American oyster, Crassostrea virginica

Pharmaceutical drugs, particularly beta-blockers (e.g., metoprolol, propranolol, etc.), are extensively used to treat human cardiovascular conditions, yet pose significant risks to non-target aquatic organisms when introduced into coastal and marine environments via wastewater effluent. This study aimed to investigate the effects of short-term exposure (one week) to environmentally relevant concentrations of metoprolol and propranolol (MP) mixtures (low-dose: 50 ng/L propranolol and 250 ng/L metoprolol, and high-dose: 250 ng/L propranolol and 650 ng/L metoprolol) in the American oyster (Crassostrea virginica, a commercially and ecologically important marine bivalve mollusk) under controlled laboratory conditions. Histopathological assessments revealed structural damage to gills, connective tissues, and digestive glands in both low- and high-dose MP treatment groups. Additionally, glucose concentration and pH of the extrapallial fluid significantly declined in the high-dose MP treatment groups. Hemocyte density in the connective tissues increased proportionally with MP dosages. MP mixtures significantly reduced mucous secretion in the gills and digestive glands. Immunohistochemical results showed significant (P < 0.05) upregulation of 3-nitrotyrosine protein (NTP, a biomarker of protein nitration) expression in tissues of oysters exposed to MP mixtures. Alongside, exposure to MP significantly (P < 0.05) decreased acetylcholinesterase (AChE, a cholinergic enzyme) expression in oyster tissues. Our findings suggest that beta-blockers induce protein nitration, leading to altered tissue morphology, disrupting extrapallial fluid homeostasis, and downregulating AChE expression that may impair physiological functions in oysters.

Lycopene alleviates splenic injury in grass carp (Ctenopharyngodon idella) caused by endoplasmic reticulum stress-autophagy axis induced by sulfamethoxazole through regulating AKT/AMPK pathway

Sulfamethozole (SMZ), an antibiotic widely used in aquaculture, is bioaccumulating and resistant to degradation, posing ecological risks. Although environmentally relevant SMZ concentrations (0.3 μg/L) are known to impair piscine immune function, the molecular mechanisms driving its toxicity remain elusive. Lycopene (LYC) is a potent bioactive compound that alleviates SMZ-induced toxicity by regulating the endoplasmic reticulum (ER) stress autophagy axis. This experiment chooses 120 grass carps, divided into 4 groups: control group (CON), SMZ exposure group (0.3 μg/L), the LYC supplement group (10 mg/kg) and SMZ + LYC combined treatment group. The toxicity of SMZ (0.3 μg/L) to grass carp and the mitigation effect of LYC (10 mg/kg) to SMZ were studied through a 30-day experiment. Histopathological alterations were evaluated via hematoxylin-eosin (H&E) staining, ultrastructural changes were visualized by transmission electron microscopy (TEM), and key biomarkers of ER stress, autophagy, and AKT/AMPK signaling were quantified through qRT-PCR and Western blotting. Results demonstrated that SMZ exposure induced disorganization of white pulp, cellular vacuolation, and activation of melanomacrophage centers (MMCs), accompanied by significant upregulation of ER stress markers (IRE1, PERK, ATF6, GRP78, eif2α) and autophagy-related genes (LC3, P62, Beclin1, ATG5). TEM revealed nuclear pyknosis, mitochondrial swelling, and increased autophagosomes in SMZ-treated splenocytes. LYC intervention markedly attenuated these pathological injuries and suppressed ER stress and excessive autophagy by modulating the AKT/AMPK pathway. Molecular docking analysis confirmed binding affinity between LYC and AKT/AMPK proteins, with a binding energy of -8.8 kcal/mol. Our findings establish a mechanistic foundation for developing LYC-enriched functional feeds to counteract antibiotic-associated ecological risks in sustainable aquaculture.

Mixture Matters: Exploring the Overlooked Toxicity of Sulfamethoxazole and Trimethoprim in Aquatic Environments

Sulfamethoxazole (SMX) and trimethoprim (TRIM) are two antibiotics included in the third Watch list to be monitored in inland waters by the Water Framework Directive. However, their mixture (MIX) is overlooked and is especially concerning because it mirrors the real conditions in natural aquatic ecosystems. This study aimed to evaluate the toxic effects of environmentally relevant concentrations of SMX (150 μg/L), TRIM (30 μg/L), and MIX (150 μg/L SMX + 30 μg/L TRIM) in different standard species: Aliivibrio fischeri (bioluminescence inhibition), Escherichia coli ATCC 25922 (growth inhibition), Lemna minor (growth inhibition and biochemical biomarkers), Daphnia magna (immobilization/mortality, reproductive effects, and biochemical biomarkers), and Danio rerio (survival, hatchability, abnormalities, and biochemical biomarkers). Considering all the parameters evaluated, and using the Independent Action model and the antibiotics ecotoxicological assessment approach, the results reveal that: (i) all antibiotics affect the bacteria A. fischeri and E. coli differently, causing a pronounced E. coli inhibition growth; (ii) SMX and MIX were slightly toxic to D. magna (after 48 h) and D. rerio (after 96 h), and moderately toxic to L. minor (after 7 days) and D. magna (after 10 days); (iii) TRIM was slightly toxic to all organisms tested, except for L. minor, which exhibited moderate toxicity; (iv) the interaction of the antibiotics in mixture varied significantly depending on the parameter; however, it revealed similar toxicity to SMX. Significant ecotoxicological data were obtained, clarifying the ecological risks of these antibiotics in aquatic ecosystems. Remaining vigilant regarding environmental contamination linked to levels of SMX and TRIM in surface waters is crucial. Assessing the combined impacts of multiple stressors is essential for prioritizing environmental safety and ecotoxicity assessments for antibiotics amidst climate change, preserving the health and integrity of aquatic ecosystems.

Integrating microbial community dynamics and emerging contaminants (ECs) for precisely quantifying the sources in groundwater affected by livestock farming

Livestock farming is a major emission source of emerging contaminants (ECs); improper management of ECs could lead to severe groundwater pollution. However, research on accurately controlling the impact of large-scale livestock pollution in groundwater and quantifying sources of ECs pollution from livestock farming to formulating effective control measures is scarce. For the first time, the groundwater near four livestock farms (broiler, dairy, aquaculture, and pig farms) was selected as the research object to characterize the ECs, analyze the impact of ECs on microbial communities, and identify the pollution sources of livestock groundwater by the fast expectation-maximization of microbial source tracking (FEAST). Significant differences in the levels of antibiotics and hormones from four livestock farms led to changes in the groundwater microbial communities. The ECs improved the uniqueness of source biomarkers, providing better help for FEAST distinguishing livestock pollution sources at various groundwater mixing ratios. This study improved the accuracy of FEAST in investigating the pollution sources in groundwater and provided experimental evidence for accurate source tracking of ECs in groundwater in large-scale areas heavily polluted by livestock farming.

Unrecognized role of photosynthetic bacteria in aquaculture water purification: Producing singlet oxygen to degrade residual pharmaceuticals

Photosynthetic bacteria (PSB) are widely used in the purification of aquaculture waters due to their ability to utilize ammonia, nitrite, hydrogen sulfide, etc. However, PSB are usually considered to be ineffective in removing biologically inert pharmaceutical residues in aquaculture waters. Herein, we found that PSB were capable of degrading pharmaceuticals in aquaculture waters, such as cimetidine and sulfamethazine, by generating extracellular singlet oxygen (1O2) under light irradiation. PSB were highly efficient to produce 1O2, and the quantum yield of 1O2 was four orders of magnitude higher than that of hydroxyl radicals. The efficient production of 1O2 by PSB arose from the photosensitization of extracellular metabolites, which produced 1O2 with an order of magnitude higher quantum yield (0.41) compared to the commonly reported dissolved organic matter (< 0.04) and could efficiently produce 1O2 even under visible light irradiation. The photosensitized extracellular metabolites were mainly hydrophobic metabolites with the molecular weight < 1 kDa, and a porphyrin (i.e., COPRO III) was identified as the dominant photosensitizer for 1O2 production. This work provides new insights into the role of PSB inoculants in aquaculture water purification, and offers new ideas for the removal of pharmaceutical residues from aquaculture waters.

Hydrogenated red mud biochar as visible-light-driven peroxymonosulfate (PMS) activators for efficient degradation of antibiotic: Resource utilization, mechanism insights and toxicity assessment

The drawbacks of low efficiency, high cost, and high energy consumption have always been main concerns for the treatment of antibiotic wastewater and massive solid wastes. In this work, a novel recyclable catalyst ((RM/BC)H) was proposed by "To treat waste with waste" and "Resource oriented utilization of solid waste". Through hydrogenation and co-pyrolysis, the new catalyst was produced by industrial waste of red mud (RM) and biomass waste as the raw materials. And then, peroxymonosulfate (PMS) was activated by (RM/BC)H to degrade tetracycline hydrochloride (TCH) aqueous solution under LED-vis light condition. The results demonstrated that the (RM/BC)H + PMS + LED-vis light system has exhibited an excellent degradation efficiency with 82.6% for TCH (TOC removal efficiency 45.6%), and the efficiency kept stable at 80% after 5 cycles. Furthermore, EPR detection and quenching experiments revealed that SO4•-, •OH, O2•- and 1O2 were generated in this system and co-participated in TCH degradation. Hydrogenation modification (RM/BC)H could improve the electron transfer efficiency and electric transfer ability of the materials. Meanwhile, the DFT calculations confirmed that Fe2+ was more conducive to the activation of PMS, and the synergistic effect of LED-vis light and PMS to form an internal cycle of Fe3+ and Fe2+ were favorable to the stability of the material. This study provides a feasible opinion on the economical and efficient degradation of antibiotic wastewater.

Microwave-assisted synthesis of self-assembled C-doped-ZnO/g-C3N4 heterojunction catalysts for effective photodegradation of ofloxacin antibiotic

In this study, carbon-doped zinc oxide (CZ45) prepared using the microwave-assisted solvothermal method was electrostatically assembled with graphitic carbon nitride (GCN) to obtain CZ45/GCN (CZCN) heterojunction photocatalysts. The obtained composites showed average sizes in the range of 19.12-20.51 nm with the disintegration of petal-like stacked GCN sheets. A significant decrease in the bandgap (E g) from 3.12 eV in CZ45 to 2.67-2.81 eV in the CZCN composites and the photoluminescence (PL) spectra indicated an enhanced charge carrier separation suitable for the catalytic application under visible light irradiation. The CZCN11 composite (E g = 2.81 eV) with a CZ45 : GCN weight ratio of 1 : 1 demonstrated outstanding photocatalytic performance in the degradation of ofloxacin (OFL) antibiotics compared to the other prepared CZCN composites as well as GCN and CZ45. The optimal parameters for OFL photodegradation by CZCN11 were determined; the CZCN11 dosage, OFL initial concentration, and pH range were found to be 1.01 g L-1, 20 ppm, and 7.0-8.0, respectively. Under these conditions, about 96% of the initial amount of OFL was decomposed at an apparent rate of 0.0173 min-1 in 180 min. A reusability test indicated the excellent durability and recyclability of CZCN11 in OFL photodegradation since the degradation efficiency was reduced only by about 1% after five successive runs without any alteration in the original structure of the composite. Furthermore, the active-charge-trapping experiments displayed the crucial role of superoxide (˙O2 -) radicals in OFL photodegradation by the CZCN composites.

Biodegradation of ciprofloxacin by a manganese-oxidizing fungus Cladosporium sp. XM01: Performance and transcriptome analysis

Biogenic manganese (Mn) oxidation presents a promising approach for ciprofloxacin (CIP) removal from wastewater, yet the interaction between Mn bio-oxidation and CIP degradation remains unclear. The Mn-oxidizing fungus Cladosporium sp. XM01 was selected as a model strain in this study, to explore the impacts of CIP on microbial growth, function and biotransformation. Results showed that CIP exhibited a promotive effect on the growth and Mn(II) oxidation capacity of XM01. After 192 h of cultivation, 39.80 %-69.19 % of CIP was removed by XM01 in the absence of Mn(II), while over 84 % was removed with 300 μM Mn(II), demonstrating both direct and Mn(II)-enhanced indirect degradation of CIP. Transcriptomic analysis revealed that the upregulation of ribosome, peroxisome, and tyrosine metabolism pathways enhanced XM01's adaptation to CIP and supported microbial growth. Cytochrome P450 (CYP450) enzymes were implicated as key mediators in CIP degradation. Additionally, in the presence of Mn(II), the further upregulation of transmembrane transporters, NAD(P)H dehydrogenase, and CYP450 indicated that Mn bio-oxidation enhanced XM01's adaptation and response to CIP, thereby accelerating its degradation. Proposed CIP degradation pathways include piperazine epoxidation, decarboxylation, and hydroxylation. This study advances the understanding of fungal Mn oxidation in antibiotic removal, emphasizing its potential in wastewater treatment.

Insights into the transformations, antimicrobial activity, and degradation efficiency of a representative carbapenem antibiotic by high-frequency ultrasound hybridized with the (photo)Fenton process

Carbapenems are potent antibiotics that reach sewage systems and then the environment, causing negative impacts. Thus, research on degrading processes to limit the carbapenem discharge in sewage systems is needed. Herein, fundamental aspects of high-frequency ultrasound alone and hybridized with the (photo)Fenton process to deal with a representative carbapenem antibiotic (meropenem, MERO) in water were considered. Initially, the action of ultrasound alone (at 578 kHz) on MERO in distilled water was tested for degradation, resulting in a partial removal (∼53 % after 120 min) and a moderate pseudo-first-order-kinetics (k: 6.3 × 10-3 min-1). Then, to enhance the MERO elimination ferrous ions were added to the ultrasound system, forming the sono-Fenton process. The increase in the ferrous ions concentration from 0 to 5 mg L-1 augmented the rate of MERO degradation (k changed from 6.3 to 15.7 × 10-3 min-1) and diminished the electric energy consumption from 1.22 to 0.49 kWh L-1. Afterward, the MERO treatment by the hybridized sono-photo-Fenton process (i.e., ultrasound combined with Fe2+ and UVA light) was evaluated, showing that the degradation efficiency was higher than by the sono-Fenton or photolysis (indeed, a synergistic index of 1.11 was obtained). Moreover, the sono-photo-Fenton process decreased the antimicrobial activity (against Staphylococcus aureus) after 30 min of treatment, indicating that the by-products did not have antimicrobial activity. The structures of primary by-products, at 50 % of MERO degradation, were elucidated through Fukui indices and LC-MS, finding that the pyrroline ring, β-lactam core, and thioether group on MERO were susceptible to the attacks of generated hydroxyl radicals (HO) and the primary transformations occurred on such moieties of the antibiotic. Finally, the treatment of MERO in synthetic hospital wastewater by the action of the sono-photo-Fenton process was assessed, degrading 36 % of MERO at 60 min of treatment. The results from this research indicated that the hybridized processes could be an alternative to be used in niche applications for treating carbapenem antibiotics even in complex matrices, transforming them into less problematic compounds.

Accelerated photo-Fenton degradation of ciprofloxacin on CoSx@TiO2 amorphous-crystalline interface with S-O bond bridging

Photo-Fenton reaction integrates the benefits of photocatalysis with traditional Fenton chemistry, producing highly reactive hydroxyl radicals for oxidizing organic pollutants into CO2 and H2O. In this study, a unique and novel interface was constructed between amorphous CoSx (cobalt sulfide) and crystalline anatase TiO2 (titanium dioxide): ultra-thin CoSx nanoflakes were directly deposited onto TiO2 nanowires. S-O bonds formed between CoSx and TiO2 establish pathways for the orderly transfer of electrons along the heterojunction interface, facilitating in-situ generation of H2O2 and realizing the high photo-Fenton activity for degrading ciprofloxacin. Under optimal conditions, the elimination rate of ciprofloxacin can reach 100 % within 100 min, and the CoSx@TiO2 composite demonstrates sustained catalytic performance over eight consecutive cycles. Density Functional Theory (DFT) calculations results confirm that CoSx@TiO2 exhibits a more favorable free energy profile compared to single TiO2 during the oxidation of water to produce ∗OH radicals. Under irradiation, integrating CoSx and TiO2 contributes mostly to generate abundant ‧OH radicals. This research provides innovative insights into optimizing photo-Fenton performance by strategically designing amorphous-crystal interfaces connected via electron-conducting bridges.

Prediction and mechanism of combined toxicity of surfactants and antibiotics in aquatic environment based on in silico method

The coexistence of surfactants and antibiotics in aquatic environments can potentially trigger combined toxic effects on aquatic organisms. Unfortunately, the effects of these joint toxins and the corresponding mechanism remain unclear. In this study, we performed individual and combined toxicity experiments involving surfactants and antibiotics. Six quantitative structure-activity relationship (QSAR) models and two traditional mixture models were developed. Moreover, the toxic mechanisms were explored with molecular dynamics (MD) simulations and density functional theory (DFT) calculations. The results shown that synergistic toxicity effects were observed in the binary mixture of levofloxacin (LEV) and octylphenol ethoxylate (Triton X-100). In addition, the best QSAR model (RF-PLS), which included four mixture descriptors (RDF155i#3, MATS3e#2, ETA_BetaP_ns#6, MLFER_E#6) exhibited excellent performance (R2 = 0.921, R2adj = 0.875, Q2LOO = 0.820, Q2ext = 0.889, and CCC = 0.954). Further analysis revealed that the electrostatic potential of different target chemicals and their binding ability with enzymes affected the activity of AChE of Daphnia magna, resulting in different toxicity. Specifically, in the AChE + Triton X-100 + LEV system, the second pollutant enhances the ability of the overall system to bind pollutants, which exhibit a synergistic effect during the binding process.

Highly antibacterial and biocompatible polylysine-modified silk fibroin for potential food preservation and biomedical applications

Bacterial infection remains a thorny problem in food, medicine, and other fields. Due to the emergence of antibiotic-resistant bacteria, it is critical to develop an effective strategy to yield novel antibacterial agents. Herein, a new type of non-antibiotic antimicrobial material was successfully synthesized by grafting ε-polylysine (EPL) onto silk fibroin (SF). The resulting ε-polylysine-modified silk fibroin (SF-EPL) possessed the possibility to be processed into different formats. As the EPL content increased, SF-EPL exhibited higher positive charge levels, similar to those of EPL. Notably, the incorporation of 10 % EPL endowed superior antibacterial effects against E. coli and S. aureus (>90 %), while maintaining excellent biocompatibility. Furthermore, SF-10%EPL effectively extended the shelf life of cherry tomatoes, significantly delaying weight loss and the decline in titratable acidity content. The obtained SF-EPL may represent a promising substitute for food preservation and biomedical applications.

Degradation of antibiotic pollutants and simultaneous CO2 capture over hollow MnO2/light/peroxymonosulfate (PMS)-CaO system

Antibiotic organic pollutants not only pose a significant threat to human health but also generate a large amount of carbon dioxide (CO2) during the treatment process of advanced oxidation processes (AOPs). Herein, the antibiotics aqueous solution was firstly degraded and mineralized by light-assisted peroxymonosulfate (PMS) activation over hollow manganese dioxide (MnO2) catalyst and then the corresponding released CO2 was effectively captured by calcium oxide (CaO) particles in the same sealed reactor, achieving wastewater treatment with zero carbon releasing. Under simulated light conditions, hollow MnO2 is excited to generate electron-hole pairs. The photo-induced electrons activate PMS, producing reactive oxygen species (ROS) such as SO4·-, 1O2, ·O2- and ·OH, which subsequently attack and degrade tetracycline (TC), resulting in the formation of CO2. After 3 h reaction, 99 % of TC was degraded while the concentration of CO2 in the sealed reaction jar increased from ca.410 ppm to ca.3066 ppm. Consequently, CaO in the same reactor captured released CO2 with the concentration decreased to 310 ppm. The capture of CO2 in the system exhibited a negligible effect on the TC degradation efficiency. This study provides a new system for the high-efficiency and low-carbon degradation of antibiotics wastewater.

Traceability analysis and risk assessment of river antibiotics based on dissolved organic matter spectral features and the positive matrix factorization receptor model

Identifying pollution sources is crucial for controlling antibiotic contamination and preventing risks to aquatic environments. This study quantified four categories of antibiotics (quinolones,macrolides, sulfonamides, and tetracyclines) in Dafeng River during the dry season using SPE-UHPLC-MS，analyzing their sources and risks. The source apportionment results for antibiotics using the Positive Matrix Factorization (PMF) model were validated against those identified based on Dissolved Organic Matter (DOM) fluorescence characteristics. Redundancy Analysis (RDA) was employed to clarify the relationship between specific source risks in the PMF model and DOM fluorescence characteristics. The findings include: (1) A total of 43 antibiotics were detected, with concentrations ranging from 19.04 to 1037.11 ng/L. The overall significant risk rate (RQ ≥ 0.01) was 55.1 %. (2) Excitation-Emission Matrix coupled with Parallel Factor Analysis (EEM-PARAFAC) identified three fluorescence components in the watershed's water body DOM: fulvic-like (C1), humic-like (C2), and tyrosine-like (C3). (3) The PMF model identified five pollution sources for antibiotics. Livestock discharge was the predominant source of concentration, while sewage treatment plants posed the primary source risk, consistent with the DOM spectroscopy results. (4) The RDA demonstrated a close relationship between DOM fluorescence characteristics and specific source risks of antibiotics.

How far do we still need to go with antibiotics in aquatic environments? Antibiotic occurrence, chemical-free or chemical-limited strategies, key challenges, and future perspectives

Global consumption and progressive migration of antibiotics through aquatic systems have contributed to their rapid spread, posing significant threats to environmental and human health, and antibiotics have been recognized as emerging pollutants. Hence, extensive approaches have been proposed for antibiotic treatment in water, yielding great achievements. This review systematically summarized current knowledge from contamination characteristics to treatment strategies. First, the prevalence and characteristics of antibiotics in aquatic environments were discussed and chemical-free or chemical-limited strategies were subsequently reviewed, i.e. adsorption, membrane separation, electrochemistry, and photocatalysis. Thereafter, gaps were identified between conditions for treatment in aquatic environments and lab-scale experiments, emphasizing that simulated antibiotic concentrations in laboratory studies were often hundreds of times higher than those found in natural settings and lack consideration of complex water matrices. Additionally, concerns regarding health risks arose due to unexpectedly low mineralization rates. For future advancements, hybrid or combined technologies were recommended, along with the integration of smart tools such as machine learning for deeper insights into degradation processes and cross-risk assessments. This review offers valuable guidance for establishing effective strategies to control antibiotics in aquatic environments.

Phytotoxicity Assessment of Solanum lycopersicum L. Seedlings Moderately Irrigated with Non-Thermal Plasma Treated Water Containing Sulfamethoxazole

Contamination of agricultural ecosystems with antibiotics including sulfamethoxazole (SMX) can create favorable conditions to increase bacterial abundance in soil with antibiotic-resistant genes and can also affect plants. The aim of this research was to assess the phytotoxicity of tomato after irrigation with SMX degraded in 20 min using the non-thermal plasma-ozonation technique (T20). To achieve this, two experiments were performed at the scales of Petri dishes and pots using Solanum lycopersicum L. species, cultivar Zaraza, subjected to irrigation treatments that were compared to a distilled water control. In plates, T20 solution improved root length and also seedling vigor indexes, but the germination index, germination speed, and biomass were slightly decreased. In soil, although T20 reduced the seedling root length, their growth was not inhibited (15.3%), while in plates they exhibited a growth promotion effect with 90% more than the control. The physical-chemical and geochemical variables measured in the soil were suitable for crop characteristics and plant growth and showed statistically significant variations after harvesting. In T20-treated shoots, compared to SMX, better results were obtained for their length, assimilatory pigments, and biomass, thus selectively reducing the tomato seedling phytotoxicity depending on the endpoints, type of control, and growth methods tested.

Interactive toxicity effects of metronidazole, diclofenac, ibuprofen, and differently functionalized nanoplastics on marine algae Chlorella sp

Pharmaceutical products (PPs) and nanoplastics (NPs) are prominent emerging contaminants that pose serious threats to marine ecosystems. The present study aimed to investigate both pristine and combined toxicity of PPs (metronidazole, diclofenac, and ibuprofen) and polystyrene nanoplastics (PSNPs) with amine (NH2-PSNPs) and carboxyl (COOH-PSNPs) surface functionalization on marine microalgae Chlorella variabilis. Toxicity assessment included the evaluation of growth inhibition, total reactive oxygen species production, malondialdehyde content, antioxidant activity, and photosynthetic activity. Furthermore, changes in the surface functional groups of the algae after exposure to contaminants were examined. The correlation among the toxicity endpoints was assessed using Pearson correlation and cluster heatmap analysis. Zeta potential analysis and hydrodynamic size measurements revealed that the PSNPs became unstable in the presence of PPs. This instability facilitated the aggregation and rapid settlement of PSNPs, consequently impeding their direct interaction with algal cells. Growth inhibition results indicated that Chlorella variabilis exhibited minimal growth inhibition when exposed to pristine PPs (1 mg L-1), whereas PSNPs (1 mg L-1) caused substantial growth inhibition. Notably, the combined toxicity of PSNPs and PPs was lower compared to pristine PSNPs. The independent action model revealed that the combination of PPs and PSNPs showed an antagonistic mode of interaction. The potential reasons for the decreased toxicity observed in the mixture of PSNPs and PPs compared to pristine PSNPs can be attributed to diminished oxidative stress and enhanced photosynthetic activity. These findings provide valuable insights into the role of PPs in modulating the toxicity of PSNPs towards microalgae.

Surface catalytic degradation of ciprofloxacin by ferrihydrite sulfidation under ambient conditions

Dissolved sulfide (S(-II)) is abundant in sediments and capable of initiating the sulfidation reactions of iron-bearing minerals, in which the reaction mechanisms have been well documented. However, the impact of the S(-II)/Fe concentration ratio on reactive oxygen species (ROS) formation and the fate of co-existing contaminants upon iron-bearing minerals sulfidation under ambient conditions remains inadequately explored. Herein, the transformation of ciprofloxacin (CIP) by ferrihydrite sulfidation under ambient conditions was systematically investigated. Our findings indicated that the rate of CIP degradation initially increased with rising S(-II)/Fe concentration ratios, but subsequently decreased as the ratio continued to elevate. Evidence from electron paramagnetic resonance, molecular probing and quenching experiments revealed that the superoxide anion radical (O2•-), primarily produced from the reaction between O2 and surface-bound Fe(II), was the dominant contributor to the accelerated transformation of CIP. Upon being attacked by ROS, CIP underwent degradation via carboxyl substitution, defluorination, hydroxylation, piperazine ring ketonization and piperazine ring cleavage. Additionally, common water quality factors, i.e., pH, natural organic matter (NOM) and inorganic anions could also significantly influence the degradation processes of CIP during ferrihydrite sulfidation under ambient conditions. This research offers valuable insights into the significant function of mineral sulfidation in facilitating the formation and reactivity of ROS, which sheds light on enhanced elimination of organic contaminants in sediments.

Distribution and risk characteristics of antibiotics in China surface water from 2013 to 2024

The continuous release of large quantities of antibiotics into the aquatic environment has led to widespread water pollution in China. Therefore, this study investigated the antibiotic pollution levels and ecological risks of surface water in seven major Chinese watersheds based on research papers from 2013 to 2024. Measured concentrations and ecotoxicity data of sulfonamides (SAs), tetracyclines (TCs), fluoroquinolones (FQs), and macrolides (MLs) in the aquatic environments of China were collected and compiled. The environmental concentration and distribution characteristics of antibiotics in seven major watersheds were statistically analyzed to carry out the evaluation of multiple ecological risks of antibiotics in watersheds across the country, and at the same time, the traceability analysis of antibiotic pollution in different regions was carried out, which will provide a certain theoretical basis for the precise management of antibiotic pollution in the future. The results showed that the distribution and environmental risks of the four antibiotics in different watersheds varied greatly, with the Yangtze River Basin, the Huanghuai Basin, and the Pearl River Basin being affected by anthropogenic activities, economic development, and other factors, with a wider range of antibiotic sampling sites and higher detection concentrations, and with the Northwestern Basin, the Southwestern Basin, and the Songhua and Liaohe River Basins having an overall lower risk of antibiotics. FQs were detected at high concentrations in all the basins, mostly posing high risk to aquatic environments. SAs were the most frequently detected but had the lowest ecological risk. The results of the more refined risk assessment (joint probability curves, JPCs) were ranked in order of risk, with FQs ≥ TCs > MLs > SAs. These results can be used as a reference for integrated management and sustainability studies on basins across the country.

Effect of antibiotics on diverse aquatic plants in aquatic ecosystems

The widespread presence of antibiotics in aquatic ecosystems, mainly due to their use in medicine and veterinary practices, poses a significant environmental challenge. Aquatic plants play a vital role in maintaining ecosystem stability, but their responses to antibiotics vary by species, influenced by differences in their traits and interactions with environmental factors. However, the specific ways antibiotics affect these plants remain poorly understood. In this study, we conducted a meta-analysis of 167 peer-reviewed studies to investigate the mechanisms of antibiotic uptake and their effects on different types of aquatic plants-submerged, emergent, and floating. Our analysis shows that antibiotics, particularly common ones like sulfonamides, tetracyclines, and quinolones, impact aquatic plants through multiple pathways. Submerged and floating plants often face widespread, direct exposure, resulting in "full-coverage" impacts, while emergent plants experience mixed exposure patterns, affecting both submerged and aerial parts and leading to "partial-coverage" impacts. These findings provide a foundation for phytoremediation strategies, enabling the rational selection and management of aquatic plant types to mitigate antibiotic pollution. Our study underscores the ecological risks posed by antibiotic contamination in aquatic ecosystems and offers a theoretical framework for developing effective restoration strategies.

Isolation of Bacillus cereus and its probiotic effect on growth performance, antioxidant capacity, and intestinal barrier protection of broilers

Probiotics are effective for improving poultry health. Probiotic Bacillus cereus strains are widely used to improve animal health by stimulating the immune system. In this study, we obtained a B. cereus 13 (BC13) strain that functions in acid, high-temperature, and bile salt resistance. It also degrades starch, cellulose, and other proteins. To better understand the probiotic effects of BC13, we added the strain to the diet of broilers and observed its effects. We found that BC13 significantly improved the growth performance of broilers. The levels of total antioxidant capacity, superoxide dismutase, and glutathione peroxidase were increased, and the concentration of malondialdehyde was reduced by BC13. Supplementation with BC13 enhanced immune function by increasing the levels of secretory immunoglobulin A (sIgA) in the jejunum mucosa; IgA, IgM, and IgG in the serum; mRNA levels of Zo-1, claudin and occludin of the jejunal mucosa; and increased villus height/crypt depth of the jejunum. Furthermore, BC13 improved the composition of intestinal microbes, especially at the genus level of Akkermansia. The addition of BC13 increased the levels of acetic, butyric, valeric, and propionic acids. These results emphasise the potential of BC13 as a probiotic dietary supplement to improve the antioxidant capacity, intestinal barrier function, and gut microbial composition to enhance body health.

The capacity of the green microalga Chlorella vulgaris in overcoming the detrimental effects of cephalexin contamination

Antibiotics have the potential to affect the health of humans and other living organisms even at slight concentrations. Therefore, there has been a growing global awareness of the environmental impacts associated with antibiotics as emerging pollutants. Cephalexin (CPX) is classified as a first-generation cephalosporin and exhibits a significant efficacy in combating bacterial infections. The current work was conducted to examine the capability of the microalga Chlorella vulgaris to mitigate CPX contamination in aquatic environments. The results indicated that the growth of microalgae diminished in a dose-dependent manner after a 6-day exposure to concentrations of 200-800 mg L- 1 CPX. The analysis conducted through scanning electron microscopy revealed alterations in cell morphology, specifically shrinkage and wrinkling, following the application of CPX. These effects became more significant as the concentration of CPX increased. The results from flow cytometry revealed a notable decrease in cell viability for all concentrations of CPX used, with the highest concentration yielding a viability rate of less than 30%. In addition, CPX caused a decrease in levels of photosynthetic pigments and non-enzymatic antioxidants, including phenols and flavonoids. However, the activity levels of the main antioxidant enzymes considerably increased, achieving their peak at 800 mg L⁻¹. Moreover, the algal cells demonstrated the capability to decrease the concentration of CPX present in the contaminated media, with the most effective reduction observed at 400 mg L- 1. The data obtained confirmed the significant toxicity of CPX on Chlorella vulgaris, while also emphasizing the ability of microalgal cells to withstand antibiotic contamination.

Rapid antibiotic biosensors based on multiple molecular recognition elements

The extensive use of antibiotics poses significant public health concerns, including the increase in drug-resistant bacteria and environmental pollution, underscoring the urgent need for rapid, sensitive, and specific antibiotic detection methods. Most current reviews on antibiotic detection primarily focus on categorizing antibiotics based on their types or the classification of sensors used, such as electrochemical, optical, or colorimetric sensors. In contrast, this review proposes a novel and systematic theoretical framework for the detection of antibiotics using sensors using seven popular molecular recognition elements-antibodies, aptamers, microorganisms, cells, peptides, molecularly imprinted polymers (MIPs), metal-organic frameworks (MOFs) and direct recognition modalities and briefly discusses the mechanism of molecular recognition elements and antibiotic recognition. Additionally, it explores biosensors developed using these elements, offering a detailed analysis of their strengths and limitations in terms of sensitivity, specificity, and practicality. The review concludes by addressing current challenges and future directions, providing a comprehensive perspective essential for enhancing food safety and protecting public health.

Trophic transfer of sulfonamide antibiotics in aquatic food chains: A comprehensive review with a focus on environmental health risks

Antibiotics, which have been identified as emerged pollutants, are creating an increase in environmental concerns, with sulfonamide antibiotics (SAs) being among the most commonly discovered antibiotics. Due to their widespread usage and inadequate sewage treatment, SAs are frequently released into the aquatic environment. The introduction of SAs into aquatic environments can kill or inhibit the growth or metabolic activity of microorganisms, thereby affecting biological communities and ecological functions and disrupting the equilibrium of aquatic ecosystems. The transmission of SAs to human beings can occur through trophic transfer of food chains, particularly when humans consume aquatic food. This study examines the trophic transfer of SAs along the aquatic food chain, provides a summarize of the spatial distribution of SAs in aquatic environments, and evaluates the environmental risks associated with it. The prevalence of SAs was predominantly noted in the aqueous phase, with relatively lower concentrations detected in sediments, solidifying their status as one of the most widespread antibiotics among aquatic organisms. SAs, characterized by their high biomagnification capacity and strong bioaccumulative properties in invertebrates, emerge as the antibiotic type with the greatest ecological risks. The ecological risk posed by sulfonamide antibiotics to aquatic organisms is more pronounced than the health risk to humans, suggesting that the adverse effects on aquatic life warrant greater attention. Additionally, this study offers practical recommendations to address the limitations of previous research, emphasizing the importance of regulating exposure and establishing a robust health risk prediction system as effective measures for antibiotic control.

From Quencher to Promoter: Revisiting the Role of 2,4,6-Trimethylphenol (TMP) in Triplet-State Photochemistry of Dissolved Organic Matter

Triplet-state dissolved organic matter (3DOM*) plays a crucial role in environmental aquatic photochemistry, with 2,4,6-trimethylphenol (TMP) frequently used as a chemical probe or quencher due to its high reactivity with 3DOM*. However, the influence of TMP-derived oxidation intermediates on the target photochemical reactions has not been comprehensively examined. This study investigated TMP's effect on the photolysis of sulfamethoxazole (SMX), a common antibiotic found in natural waters, in the presence of different DOM sources or model photosensitizer. Contrary to expectation, TMP significantly accelerated SMX photolysis, with the extent of enhancement depending on TMP and DOM concentrations. Laser flash photolysis and kinetic modeling suggested the long-lived TMP-derived reactive species (TMP-RS), including phenoxyl radicals, semiquinone radicals, and quinones, as the key factors in this process. Unlike 3DOM*, TMP-RS may react with SMX with the formation of non-SMX•+ intermediates. This process prevents the reduction of SMX•+ and the subsequent regeneration of SMX. The kinetic model successfully predicts the dynamic contributions of various factors to SMX oxidation during the reaction, highlighting the critical role of TMP-RS. This study advances our understanding of TMP's involvement in triplet-state photochemistry and suggests a reconsideration of the role long-lived organic RSs play in the transformation of environmental micropollutants.

Multiomics unraveled that gibberellin signaling underlies adaptation of rice to ciprofloxacin stress: Calling for concerns on the adverse effects of pharmaceutical residues in water during agricultural irrigations

Residual concentrations of antibiotics in water can reach ng mL-1 - µg mL-1 levels, which pose high risks to crops during irrigation; however, the interactions between rice and antibiotics, as well as the defense mechanisms of rice at their early growth phase remain unclear. In this study, we investigated the uptake dynamics of a ubiquitously found antibiotic, ciprofloxacin (CIP) at 0.1, 1, 6.5, and 20 µg mL-1 in rice seedlings. We found gradually bioaccumulated CIP induced significant physiological changes including inhibited growth of roots and leaves of rice seedlings, and decreased pigment contents, which can be caused by disrupted homeostasis of reactive oxygen species. Integrating roots transcriptomics, metabolomics, and validation experiments, we found that rice seedlings synthesized more gibberellins to trigger the expression of transcription factors such as group VII ethylene response factors, which induced metabolic reprogramming to yield more fatty acids derivates. These compounds including eicosanoids, isoprenoids, and fatty acids and conjugates can act as signaling molecules, as well as antioxidants and energy sources to achieve rice recovery. This conclusion is supported by the evidence showing that adding gibberellins in rice seedlings culture decreased the accumulated CIP and improved rice growth; whilst, disrupting gibberellin signaling pathway using paclobutrazol as an inhibitor increased uptaken CIP in both roots and leaves with augmenting the antibiotic stress on rice. This study has demonstrated a gibberellin-based defense mechanism in rice for defense of CIP stress, which might have significant environmental applications since we can add minor gibberellins to reduce bioaccumulated CIP with simultaneously promoting rice growth at their early phases.

Seasonal variability and risk evaluation of emerging organic contaminants in European river: Linking in silico and in vitro approaches to prioritize hazardous EOCs

Emerging organic contaminants (EOCs) are a growing concern for aquatic ecosystems, underscoring the need for advanced risk assessment methodologies. This study employed an integrated approach to evaluate the risks associated with 563 EOCs across 13 monitoring sites along the Sava River in Croatia. Sampling was conducted during the winter and spring months, spanning February to May. The detected substances, totaling 551 compounds, included pharmaceuticals, illicit drugs, pesticides, industrial chemicals, hormones, artificial sweetener, and sunscreen chemical. We hypothesized that combining high-resolution chemical monitoring with bio-effect assessment tools could enhance the prioritization of high-risk EOCs and their mixtures. Persistent, bioaccumulative, and toxic (PBT) profiling and risk quotient (RQ) evaluations identified pesticides and industrial chemicals as key contributors to biological impacts, peaking in April due to agricultural activities. In vitro prioritization using exposure-activity ratios (EARs) derived from the ToxCast database revealed exacerbated biological effects during colder months (February and March), driven by elevated levels of pharmaceuticals, particularly synthetic glucocorticoids used for treatments of respiratory infections. By integrating PBT, RQ, and EAR assessments, eight EOCs, including methylprednisolone (a synthetic glucocorticoid), bisphenol A (an industrial chemical), nicotine (a stimulant), and five pesticides (temephos, disulfoton, pyridaben, bifenthrin, and chlorpyrifos-methyl), were prioritized for monitoring and regulatory attention. This multi-method framework advances next-generation risk assessment, offering critical insights for managing EOC pollution and safeguarding aquatic ecosystems and public health.

Variable cyanobacterial death modes caused by ciprofloxacin in the aquatic environment: Prioritizing antibiotic-photosynthetic protein interactions for risk assessment

Antibiotics continuously discharged into the aquatic environment pose threats to phototrophs via high-affinity binding to photosynthetic apparatuses and interfering with their energy metabolism and growth. However, studies attributed the sublethal effects of antibiotics on phototrophs to damaging photosystem (PS) II (PSII) proteins while neglecting PSI proteins as potential targets. Herein, we report that frequently detected ciprofloxacin (CIP) with concentrations of 3-8 μg/L was lethal to Microcystis aeruginosa, the widely distributed phytoplankton in freshwater, via damaging DNA. Besides, CIP damages on different photosynthetic proteins at different exposure levels were evidenced to influence the cyanobacterial death phenotypes. In detail, CIP at 3 μg/L bound to PSII D1 protein exclusively, activating the tricarboxylic acid cycle for energy and proline catabolism. This favored the execution of apoptosis-like regulated cell death (RCD). However, CIP at 8 μg/L exhibited additional binding to the PSI iron-sulfur reaction center, apart from PSII, inducing carbon and arginine starvation. This shifted the RCD from apoptosis-like RCD to mazEF-mediated RCD. Furthermore, microcystin-LR risks were elevated after CIP exposure with enhanced microcystin-LR release and biosynthesis for apoptosis-like and mazEF-mediated RCD, respectively. Thus, the present study underscores the intricate interactions between antibiotics and different photosynthetic apparatuses, which alter antibiotic lethal effects at different exposure levels. This could provide new perspectives on the risk assessment and prediction of antibiotics from the standpoint of chemical-photosynthesis interactions.

Facile fabrication of novel magnetic chitosan@Ag-MWCN nanocomposite for the adsorptive removal of ciprofloxacin from aqueous solutions

Pharmaceuticals are known as challenging class of water pollutants that threaten worldwide waterbodies. Even in negligible concentrations, antibiotics could lead to the development of antibiotic resistance genes. In environmental and health protection against antibiotics, adsorption is a promising technique, and designing effective, sustainable, and non-toxic adsorbents is crucial. Herein, a magnetic chitosan@Ag-multiwalled carbon nanotube nanocomposite (MC@Ag-MWCN) was synthesized and applied to eliminate a common antibiotic ciprofloxacin (CIP) from aqueous solutions. FESEM, TEM, XRD and FTIR, techniques characterized the as-synthesized MC@Ag-MWCN. The study evaluates the efficacy of the various key factors such as pH, varied initial CIP concentrations, nanocomposite doses and contact time in CIP uptake. Experimental equilibrium and kinetic data were analyzed utilizing four commonly used isotherm models: Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich. Notably, the Langmuir isotherm model fitted best to CIP removal data by MC@Ag-MWCN with a qe of 31.26 mg/g. Also, the adsorption data correlated well with the pseudo-second-order kinetics model. Adsorption mechanism the removal of CIP using the MC@Ag-MWCN nanocomposite occurs through a combination of physical and chemical interactions, facilitated by the composite's structural and chemical properties. In conclusion, MC@Ag-MWCN shows promising adsorptive characteristics against recalcitrant antibiotic CIP.

Selected emerging contaminants in water: Global occurrence, existing treatment technologies, regulations and associated risk

Emerging contaminants (ECs) in aquatic environments have recently attracted the attention of researchers due to their ubiquitous occurrence and the potential risk they may pose to life. While advance analytical methods have improved global reporting in water matrices, additional information is needed to compile data on their occurrence, existing legislation, treatment technologies and associated human health risks. Therefore, the present study provides an overview of the occurrence of selected ECs, including personal care product, antibiotics, NSAIDs, EDCs and psychiatric drugs, the existing regulatory framework and their toxicological effects on human health. The water matrices under review are the treated wastewater, surface water, groundwater and, in a few cases, drinking water. The study also highlights different treatment technologies available, and evaluates their performance based on the removal efficiency for different classes of ECs. For removal of almost all ECs considered, ozonation integrated with gamma radiation was reported highly efficient. Risk analysis was also performed for selected ECs including diclofenac, ibuprofen, naproxen, carbamazepine, estrone, 17 β-estradiol, bisphenol A, sulfamethoxazole, erythromycin and triclosan. The human health risk analysis indicated the highest number of locations with potential risk due to the EDCs, with South America, Europe and Asia having multiple risks due to estrone and Bisphenol A. The results of this study will give a better insight into the current situation of ECs in the global water matrices, the performance assessment of treatment technologies and the risk analysis will describe the need for more robust regulatory structures around the world to prevent the occurrence of such contaminants in the aquatic environment.

Co-occurrence of cadmium and ciprofloxacin in environmental media decreases ciprofloxacin degradation by biogenic manganese oxides

The coexistence of antibiotics with heavy metals is detrimental to humans and the environment. In urban water environments, Cadmium (Cd) and ciprofloxacin (CIP) frequently co-occur. Biogenic manganese oxides (BMOs) are a promising environmental bioremediation material due to their remarkable adsorption and oxidation properties. However, BMOs' removal mechanism in an environment where Cd and CIP co-occur is not yet unknown. We identified a manganese (Mn)-oxidising bacterium, Bacillus sp. XM02, with a strong ability for Mn (II) oxidation (85.23%) and BMOs production, and investigated its competitive removal mechanism in an environment with Cd and CIP co-occurrence. The BMOs exhibited a glorious CIP degradation ability and led to a marked decrease in the toxicity of CIP following oxidative degradation in Escherichia coli experiments. In contrast, in the co-existence of Cd and CIP, Cd hindered CIP removal by BMOs, but CIP did not affect Cd removal. Kinetic experiments combined with XPS characterisation revealed that the k value of Cd (297.39 h-1) was much higher than that of CIP (5.53 h-1), demonstrating that Cd was immediately adsorbed onto the surface of BMOs through a Cd-O bond. The surface potentials of BMOs carrying Cd alone and both Cd and CIP on the surface were similar, revealing that the electronegativity of Cd-carrying BMOs was greatly weakened (from -34.8 mV to -21 mV/-23 mV), which further reduced the BMOs' electrostatic interaction with CIP. Moreover, the concentration of dissolved Mn (III) in the co-existence group was lower than that in the CIP alone, indicating that the presence of Cd reduced the transformation of Mn (IV) to Mn (III) by BMOs. Consequently, Cd attenuated the effect of active Mn (IV) sites of BMOs on CIP's piperazine ring oxidative degradation. These results offer a theoretical direction for the use of BMOs to reduce the risk posed by antibiotics and heavy metals pollution in co-occurrence environments.

Bjerkandera adusta TM11 for the bioremediation of fluoroquinolone antibiotics spiked in wastewater: A sustainable approach to pharmaceutical contaminant biotransformation

Global antibiotic consumption is increasing dramatically. Antibiotic release into the environment, primarily through wastewater discharge, has serious impacts for human and animal health and microbial ecosystems. To address this issue, white-rot fungi present a promising solution, as they possess oxidative enzymes that can degrade these pollutants. Here we investigated the effectiveness of the white-rot fungus Bjerkandera adusta TM11 for removing three persistent fluoroquinolone antibiotics, i.e. levofloxacin, ciprofloxacin, and enrofloxacin, in real wastewater. The three antibiotics were added to the wastewater separately at a concentration of 30 mg/L and together in a cocktail at 10 mg/L, then incubated for 9 days. LC-MS/MS analysis and anti-microbial assay (against Escherichia coli) demonstrated complete removal of levofloxacin by day 7. However, ciprofloxacin and enrofloxacin biotransformed into degradation products that still had antimicrobial activity, with degradation efficiencies reaching 82 % and 99 %, respectively, by day 7. Proteomic analysis identified 21 fungal heme peroxidases. Versatile peroxidase was the most strongly-produced enzyme potentially involved in antibiotic biotransformation. Degradation products were characterized by LC-MS/MS analysis, and a degradation pathway was proposed based on these findings.

Heterogeneous Fenton degradation of ciprofloxacin by RM-Co PBA prepared with red mud as iron source and carrier

Loading catalysts onto carriers to prepare supported catalysts is an important strategy for improving dispersion, stability and catalytic performance. In this study, we synthesized a supported red mud (RM)-based Fe-Co Prussian blue analogue (RM-Co PBA) catalyst using RM as iron source and carrier by acid dissolution-reduction-coprecipitation method to activate H2O2 for the degradation of ciprofloxacin (CIP). The RM-Co PBA obtained under the synthesis conditions of HCl concentration of 2.4 M and potassium cobalt cyanide addition of 4 mM exhibited the best dispersibility and regular shape, resulting in high catalytic performance. The degradation efficiency of RM-Co PBA/H2O2 system reached 75.79% in 10 min, which was 10.54 times and 1.21 times of that of RM/H2O2 system and Fe-Co PBA/H2O2 system, respectively. The RM-Co PBA/H2O2 system was almost unaffected by pH and was suitable for treating low concentration CIP wastewater. Additionally, the system can be reused well and possessed certain resistance to inorganic anions. The results showed that superoxide radical (⋅O2-) was the main ROS attacking CIP, which accumulated continuously in the cycling process of Co(III)/Fe(III) and Co(II)/Fe(II). On the other hand, the presence of a large number of oxygen vacancies in RM-Co PBA enhanced the production of ⋅O2- by endowing it with good electron transfer performance. Finally, we proposed possible CIP degradation pathways and demonstrated the toxicity reduction of each pathway by a quantitative structure-activity relationship analysis. This study provides guidance for the resource utilization of RM and the efficient treatment of antibiotic wastewater.

From river to groundwater: Antibiotics pollution, resistance prevalence, and source tracking

The extensive use of antibiotics has led to their frequent detection as residues in the environment. However, monitoring of their levels in groundwater and the associated ecological and health risks remains limited, and the impact of river pollution on groundwater is still unclear. This study focused on the highly urbanized Maozhou River and its groundwater. Forty-five antibiotics and microbial community composition were analyzed by high-resolution LC-MS/MS and 16S rRNA gene sequencing, respectively. These endpoints were measured in sediment, surface- and groundwater sampled during wet and dry seasons, while isolation and resistance profiling of Escherichia coli was performed in groundwater. This study aimed to assess the ecological and health risks posed by antibiotics in the Maozhou River and its groundwater, to assess the prevalence and type of antimicrobial resistance in Escherichia coli, and to trace the sources of antibiotic resistance genes (ARGs) in groundwater. Multiple antibiotics detected in the river and sediment were predicted to pose high risks to algae growth and bacterial resistance selection. In groundwater, the antibiotics erythromycin and norfloxacin were predicted to pose a medium risk to algae and a low risk towards bacterial resistance. Furthermore, significant positive correlations were observed between several predominant bacterial phyla in the river and groundwater and the detected antibiotics, suggesting a possible effect of local antibiotic residues on bacterial community composition. Antimicrobial susceptibility testing of 76 Escherichia coli isolates revealed 74 % exhibited resistance to at least one tested antibiotic and 7.9 % exhibiting multidrug resistance, which was confirmed by ARG-targeted PCR analysis. SourceTracker analysis of ARGs in groundwater indicated that ARG contamination in shallow groundwater was primarily from river sediments, while contamination in deeper groundwater originated mainly from river water. The results emphasize the need to address river pollution, as it directly impacts groundwater quality, particularly in areas with severe antibiotic contamination.

First evidence that antibiotic-resistant bacteria are inactivated by chemical species produced through the solar photosensitization of ciprofloxacin in water

For the first time, using a chemical pollutant (an antibiotic) as a photosensitizer to improve the elimination of a microbiological contaminant of emerging concern (antibiotic-resistant bacteria) is presented. The effect of ciprofloxacin (CIP) on the inactivation of three light-promoted antibiotic-resistant bacteria (ARB) was evaluated. Ciprofloxacin-resistant Escherichia coli, ciprofloxacin-resistant Staphylococcus aureus, and carbapenem-resistant Klebsiella pneumoniae. Firstly, the photosensitizing effect of CIP on E. coli inactivation was studied. Irradiated CIP (1 ppm) induced superoxide anion radical formation (confirmed through EPR analyses), and the combination of these reactive oxygen species (ROS) with ongoing solar radiation exposure enhanced bacterial inactivation. CIP enhanced the disinfection of antibiotic-resistant E. coli (by 1.84 log units at 120 min of irradiation) and improved the inactivation of K. pneumoniae (by 3.48 log units at 135 min)-both Gram-negative bacteria. Conversely, the photo-inactivation of the Gram-positive bacteria S. aureus did not significantly change (just a slight reduction of 0.42 log units at 120 min) by the presence of CIP. Showing the bacterial structure influences the disinfection process. Another critical factor was antibiotic concentration. A high CIP concentration (10 ppm) induced an interfering screen effect, while a low concentration promoted bacteria inactivation via photosensitization (in Gram-negative bacteria). Interestingly, no photosensitizing effect was observed when CIP was replaced by levofloxacin (LEV, another fluoroquinolone antibiotic), indicating a strong dependence on antibiotic structure. Additionally, the effect of the light source on photosensitized inactivation was evaluated, substituting sunlight with UVC irradiation. Under UVC light, CIP worsened ARB photo-inactivation, suggesting disinfection was mainly due to direct light action on microorganisms rather than photosensitization. Finally, the influence of water components on sunlight-photosensitized disinfection was examined using simulated urine and freshwater. The ARB inactivation decreased as matrix complexity increased. Thus, the effectiveness order was Milli-Q water > freshwater > urine.

Environmental and toxicological aspects of sulfamethoxazole photodegradation in the presence of oxidizing agents

Sulfamethoxazole (SMX) is a popular active substance, which is extensively applied to treat bacterial infections in humans and animals. Due to its widespread use, SMX enters the natural environment, where it can undergo degradation. Similarly to other emerging contaminants, SMX photodegradation and the use of oxidants in wastewater treatment processes can lead to the formation of potentially adverse transformation products for ecosystems. This study investigated the efficiency of SMX photodegradation in the presence of oxidizing agents (H2O2 and Fenton reagent). The potential environmental consequences of degradation product formation were analyzed based on experimental toxicity characterization. Standardized tests employing diverse organisms were utilized: Alivibrio fischeri (Microtox®), Daphnia magna (Daphtoxkit F®), and Lemna minor (Lemna sp. GIT). The potential environmental impact of the products identified in the reaction mixtures was evaluated using parameters describing aqueous solubility, hydrophobicity, toxicity, bioconcentration, persistence, and mobility. The analysis revealed that photodegradation produces transformation products with higher toxicity than SMX, as confirmed by in vitro tests of the reaction mixtures. Most of the detected compounds were found to have low mobility potential. The formation rates of key environmentally relevant transformation products, such as 1,4-benzoquinone, aniline, and phenol, were also discussed. The changes in total organic carbon (TOC) affected by photodegradation under the influence of the considered oxidizing agents were characterized.

Removal of Antibiotics in Breeding Wastewater Tailwater Using Microalgae-Based Process

Ciprofloxacin (CIP) and oxytetracycline (OTC) are commonly detected antibiotic species in breeding wastewater, and microalgae-based antibiotic treatment technology is an environmentally friendly and cost-effective method for its removal. This study evaluated the effects of CIP and OTC on Scenedesmus sp. in the breeding wastewater tailwater and the removal mechanisms of antibiotics. The results showed that Scenedesmus sp could increase antibiotic tolerance by enhancing antioxidant system activity. Compared to CIP, Scenedesmus sp showed better performance for OTC removal, the removal efficiencies were 100%, 96.87%, 95.75%, 90.18% and 83.91% at 0.1, 0.5, 1, 5, and 10 mg L- 1 OTC, respectively. The removal routes indicated that CIP was mainly removed by biodegradation (38.88%) and photolysis (14.30%) whereas OTC was mainly removed by hydrolysis (43.47%) and biodegradation (33.45%). Product toxicity predictions showed that most of the degradation products of CIP and OTC were less toxic than their parent compounds, confirming the feasibility of microalgae biotreatment for antibiotic removal.

Study on toxicity responses in Xenopus tropicalis long-term exposure to norfloxacin, oxytetracycline and arsenic

The presence of residues of antibiotics and heavy metals in the global aquatic environment is a widespread potential environmental risk. Here, we studied their effect on Xenopus tropicalis by analysing the hepatotoxic effects of norfloxacin (NOR), oxytetracycline (OTC), and arsenic (As) on its histology, lipidomics, proteases, and cytokines. The results showed that development was inhibited, and additional vacuolation, sinusoids, pyknosis, nuclei, cell lysis, and leukocyte infiltration were observed in the liver after 72 days of exposure to NOR (0.1-4.0 mg L-1), OTC (0.1-4.0 mg L-1), and/or As (0.3-3.5 μg L-1). In addition, the size and number of lipid droplets increased with the superposition of drugs, disrupting lipid droplet homeostasis. Lipidomics proved that the intensity of lipid responses related to lipid metabolism was disrupted, especially for CerP and TAG. In addition, the lipotoxicity induced by joint exposure was more potent than that induced by a single exposure. Compared with the controls, the ROS levels in the liver were 7.21%-37.18% greater, which promoted oxidative stress damage. By revealing the underlying mechanisms involved, we found that the liver can resist oxidative stress and lipid peroxidation by regulating the expression of multiple cytokines. Our study provides new insights into the hepatotoxicity and underlying mechanisms in aquatic amphibians caused by long-term exposure to low concentrations of NOR, OTC, and/or As.

Visible-Light-Driven Degradation of Chloramphenicol Using CeO2 Nanoparticles Prepared by a Supercritical CO2 Route: A Proof of Concept

Recently, the extensive use of antibiotics has unavoidably resulted in the discharge of significant quantities of these drugs into the environment, causing contamination and fostering antibiotic resistance. Among various approaches employed to tackle this problem, heterogeneous photocatalysis has emerged as a technique for antibiotic degradation. This study explores the potential of CeO2 as a photocatalyst for the degradation of chloramphenicol. Supercritical antisolvent (SAS) processing was successfully employed to synthesize photocatalyst precursor nanoparticles. After thermal annealing, the CeO2 samples were characterized through UV-Vis diffuse reflectance spectroscopy to evaluate the band gap energy values. Raman and FT-IR spectroscopy confirmed the presence of oxygen vacancies in the CeO2 lattice. During photocatalytic experiments, the CeO2 derived from the SAS-processed precursor exhibited superior photocatalytic performance compared to the catalyst synthesized from the non-micronized precursor. Various annealing temperatures were employed to tune the oxygen vacancy of CeO2. Furthermore, the impact of catalyst dosage and chloramphenicol concentration was investigated. Under optimal reaction conditions (25 mg L-1 chloramphenicol and 2.25 g L-1 catalyst dosage), a degradation efficiency of 64% was achieved. Finally, to elucidate the degradation mechanism, different scavengers (EDTA, benzoquinone, and isopropyl alcohol) were utilized, revealing that the superoxide radical is the primary species responsible for chloramphenicol degradation.

Development of pilot-scale plasma bubble reactors for efficient antibiotics removal in wastewater

Plasma bubble (PB) is a promising technology to control antibiotic wastewater pollution. However, the practical implementation of PB technology at the industrial-scale is still underdeveloped. In addition, the influence of different discharge modes for PB on wastewater treatment is largely unknown. This study designed pilot-scale PB reactors with different discharge modes to investigate the degradation effect of norfloxacin (NOR) and tetracycline (TC) in bulk tap water. Results indicate that the dielectric barrier discharge (DBD) mode with low average discharge power demonstrates superior degradation ability and higher production of O3(g) and .O2-(aq) compared to the spark mode which exhibits the high-intensity spark discharge in the tip area of the tube. After 40 min of treatment in a Double DBD reactor, 97.4% and 100% of NOR and TC are removed from 2 L tap water, attributed to the accumulation of antibiotic molecules by PBs and the in-situ generation of O3(g) and .O2-(aq) produced by plasma. Furthermore, a larger-scale PB reactor is developed by creating an array of four DBD reactors, effectively degrading 8 L mixed antibiotics solution. This study provides valuable insights for PB reactor design and the degradation performance of antibiotic wastewater, which will contribute to the further development of synergistic systems for plasma degradation.

Occurrence and ecological risks of antibiotics and antiparasitics in surface water in urban lakes in Hanoi city, Vietnam

The presence of antibiotics in the environment is of significant concern due to their adverse effects on aquatic ecosystems. This study provides an assessment of potential ecological risks (RQ) associated with the concentrations of eight antibiotics and antiparasitics (amoxicillin-AMO, azithromycin-AZI, ciprofloxacine-CIP, ofloxacine-OFL, oxfendazole-OXF, lincomycin-LIN, sulfacetamide-SCE and sulfamethoxazole-SME) in the surface water of 13 urban lakes in Hanoi city, Vietnam during the period 2021-2023. The findings revealed considerable variations in the total concentrations of these 8 substances (TAB), ranging from below the method detection limit (< MDL) to 2240 ng L-1 with an average of 330.4 ng L-1. Among the 8 antibiotics and antiparasitics examined, OXF, AMO, and SCE were undetectable, while the others were present at a range of concentrations (in ng L-1): OFL: 129 (< MDL-1530); CIP: 87.1 (< MDL-608); LIN: 72.7 (< MDL-676); SME: 41.5 (< MDL-504); AZI: 0.03 (< MDL-1). The calculated RQ values for these antibiotics in the Hanoi lakes indicated a high ecological risk for OFL and CIP to bacteria, a medium to high risk for SME for phytoplankton, a high risk for LIN to phytoplankton, while the risk for invertebrates was deemed negligible for all antibiotics across all lakes. The strong, positive correlation between TAB concentrations and different microbial and environmental variables (Escherichia coli, ammonium, phosphate, and chemical oxygen demand) suggests that untreated domestic wastewater is the primary pollution source in these Hanoi lakes. These results should be used to raise public awareness and to encourage the implementation of strategies targeted at managing antibiotic use. They also underscore the need to reduce inputs of untreated, antibiotic-containing wastewater into urban lakes, such as those in Hanoi and advocate for the establishment of national limits for antibiotic concentrations in surface water.