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Choi JH, Lee JH, Jo AH, Choi YJ, Choi CY, Kang JC, Kim JH. Microplastic polyamide toxicity: Neurotoxicity, stress indicators and immune responses in crucian carp, Carassius carassius. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 265:115469. [PMID: 37742571 DOI: 10.1016/j.ecoenv.2023.115469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 09/05/2023] [Accepted: 09/10/2023] [Indexed: 09/26/2023]
Abstract
This study aimed to determine the toxicity standard and potential risks and effects of polyamide (PA) exposure on neurotoxicity, stress indicators, and immune responses in juvenile crucian carp Carassius carassius. Numerous microplastics (MPs) exists within aquatic environments, leading to diverse detrimental impacts on aquatic organisms. The C. carassius (mean weight, 23.7 ± 1.6 g; mean length, 13.9 ± 1.4 cm) were exposed to PA concentrations of 0, 4, 8, 16, 32 and 64 mg/L for 2 weeks. Among the neurotransmitters, the acetylcholinesterase (AChE) activity in the liver, gill, and intestine of C. carassius was significantly inhibited by PA exposure. Stress indicators such as cortisol and heat shock protein 70 (HSP70) in the liver, gill, and intestine of C. carassius were significantly increased, while immune responses to lysozyme and immunoglobulin M (IgM) were significantly decreased. Our study demonstrates the toxic effects of MP exposure on crucian carp's neurotoxicity, stress indicators, and immune responses.
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Affiliation(s)
- Jae-Ho Choi
- Department of Aquatic Life Medicine, Pukyong National University, Busan 608-737, the Republic of Korea
| | - Ju-Hyeong Lee
- Department of Aquatic Life Medicine, Pukyong National University, Busan 608-737, the Republic of Korea
| | - A-Hyun Jo
- Department of Aquatic Life and Medical Science, Sun Moon University, Asan-si, the Republic of Korea
| | - Young Jae Choi
- Inland Fisheries Research Institute, National Institute of Fisheries Science, Geumsan 32762, the Republic of Korea.
| | - Cheol Young Choi
- Division of Marine BioScience, Korea Maritime and Ocean University, Busan 49112, the Republic of South Korea.
| | - Ju-Chan Kang
- Department of Aquatic Life Medicine, Pukyong National University, Busan 608-737, the Republic of Korea.
| | - Jun-Hwan Kim
- Department of Aquatic Life Medicine, College of Ocean Sciences, Jeju National University.
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Tang Z, Kong Y, Qin Y, Chen X, Liu M, Shen L, Kang Y, Gao P. Performance and degradation pathway of florfenicol antibiotic by nitrogen-doped biochar supported zero-valent iron and zero-valent copper: A combined experimental and DFT study. JOURNAL OF HAZARDOUS MATERIALS 2023; 459:132172. [PMID: 37523963 DOI: 10.1016/j.jhazmat.2023.132172] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 07/10/2023] [Accepted: 07/26/2023] [Indexed: 08/02/2023]
Abstract
Fluorinated compounds are a class of organic substances resistant to degradation. Although zero-valent iron (Fe0) has a promising reducing capability, it still fails to degrade fluorine-containing antibiotics (i.e., florfenicol) efficiently. In this study, we applied a simple one-pot pyrolytic approach to synthesize nitrogen-doped biochar supported Fe0 and zero-valent copper (Cu0) composite (Fe/Cu@NBC) and investigated its performance on florfenicol removal. The results clearly showed that approximately 91.4% of florfenicol in the deionized water was removed by Fe/Cu@NBC within 8 h. As the reaction time was extended to 15 d, the total degradation rate of florfenicol reached 96.6%, in which the defluorination and dechlorination rates were 73.2% and 82.1%, respectively. Both experimental results and density functional theory calculation suggested that ∙OH and ·O2- triggered β-fluorine elimination, resulting in defluorination prior to dechlorination. This new finding was distinct from previous viewpoints that defluorination was more difficult to occur than dechlorination. Fe/Cu@NBC also had a favorable performance for removal of florfenicol in surface water. This study provides a new insight into the degradation mechanism and pathway of florfenicol removal in the Fe/Cu@NBC system, which can be a promising alternative for remediation of fluorinated organic compounds in the environment.
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Affiliation(s)
- Zheng Tang
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
| | - Yifan Kong
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
| | - Yan Qin
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
| | - Xiaoqian Chen
- Bioassay and Safety Assessment Laboratory, Shanghai Academy of Public Measurement, 201203 Shanghai, China
| | - Min Liu
- Bioassay and Safety Assessment Laboratory, Shanghai Academy of Public Measurement, 201203 Shanghai, China
| | - Lu Shen
- Bioassay and Safety Assessment Laboratory, Shanghai Academy of Public Measurement, 201203 Shanghai, China
| | - Yanming Kang
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
| | - Pin Gao
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou 215009, China; National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agroenvironmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.
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Shen L, Zhang P, Lin Y, Huang X, Zhang S, Li Z, Fang Z, Wen Y, Liu H. Polystyrene microplastic attenuated the toxic effects of florfenicol on rice (Oryza sativa L.) seedlings in hydroponics: From the perspective of oxidative response, phototoxicity and molecular metabolism. JOURNAL OF HAZARDOUS MATERIALS 2023; 459:132176. [PMID: 37523959 DOI: 10.1016/j.jhazmat.2023.132176] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/16/2023] [Accepted: 07/26/2023] [Indexed: 08/02/2023]
Abstract
Antibiotics and microplastics (MPs) are two emerging pollutants in agroecosystems, however the effects of co-exposure to antibiotics and MPs remain unclear. The toxicity of florfenicol (FF) and polystyrene microplastics (PS-MPs) on rice seedlings was investigated. FF and PS-MPs caused colloidal agglomeration, which changed the environmental behavior of FF. FF inhibited rice growth and altered antioxidant enzyme (superoxide dismutase, peroxidase, and catalase) activities, leading to membrane lipid peroxidation; impaired photosynthetic systems, decreased photosynthetic pigments (Chlorophyll a, Chlorophyll b, and carotene), chlorophyll precursors (Proto IX, Mg-Proto IX, and Pchlide), photosynthetic and respiratory rates. The key photosynthesis related genes (PsaA, PsaB, PsbA, PsbB, PsbC, and PsbD) were significantly down-regulated. The ultrastructure of mesophyll cells was destroyed with chloroplast swelling, membrane surface blurring, irregular thylakoid lamellar structure, and number of peroxisomes increased. PS-MPs mitigated FF toxicity, and the IBR index values showed that 10 mg∙L-1 PS-MPs were more effective. Metabolomic analysis revealed that the abundance of metabolites and metabolic pathways were altered by FF, was greater than the combined "MPs-FF" contamination. The metabolism of amino acids, sugars, and organic acids were severely interfered. Among these, 15 metabolic pathways were significantly altered, with the most significant effects on phenylalanine metabolism and the citric acid cycle (p < 0.05).
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Affiliation(s)
- Luoqin Shen
- School of Environmental Science and Engineering, Key Laboratory of Solid Waste Treatment and Recycling of Zhejiang Province, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province, China
| | - Ping Zhang
- School of Environmental Science and Engineering, Key Laboratory of Solid Waste Treatment and Recycling of Zhejiang Province, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province, China
| | - Yanyao Lin
- School of Environmental Science and Engineering, Key Laboratory of Solid Waste Treatment and Recycling of Zhejiang Province, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province, China
| | - Xinting Huang
- School of Environmental Science and Engineering, Key Laboratory of Solid Waste Treatment and Recycling of Zhejiang Province, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province, China
| | - Siyi Zhang
- School of Environmental Science and Engineering, Key Laboratory of Solid Waste Treatment and Recycling of Zhejiang Province, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province, China
| | - Zhiheng Li
- School of Environmental Science and Engineering, Key Laboratory of Solid Waste Treatment and Recycling of Zhejiang Province, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province, China
| | - Zhiguo Fang
- School of Environmental Science and Engineering, Key Laboratory of Solid Waste Treatment and Recycling of Zhejiang Province, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province, China
| | - Yuezhong Wen
- MOE Key Laboratory of Environmental Remediation & Ecosystem Health, Institute of Environmental Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, Zhejiang Province, China
| | - Huijun Liu
- School of Environmental Science and Engineering, Key Laboratory of Solid Waste Treatment and Recycling of Zhejiang Province, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province, China.
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An Overview of Analytical Methods to Determine Pharmaceutical Active Compounds in Aquatic Organisms. Molecules 2022; 27:molecules27217569. [DOI: 10.3390/molecules27217569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
There is increasing scientific evidence that some pharmaceuticals are present in the marine ecosystems at concentrations that may cause adverse effects on the organisms that inhabit them. At present, there is still very little scientific literature on the (bio)accumulation of these compounds in different species, let alone on the relationship between the presence of these compounds and the adverse effects they produce. However, attempts have been made to optimize and validate analytical methods for the determination of residues of pharmaceuticals in marine biota by studying the stages of sample treatment, sample clean-up and subsequent analysis. The proposed bibliographic review includes a summary of the most commonly techniques, and its analytical features, proposed to determine pharmaceutical compounds in aquatic organisms at different levels of the trophic chain in the last 10 years.
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Liu Y, Hua Z, Lu Y, Gu L, Luan C, Li X, Wu J, Chu K. Quinolone distribution, trophodynamics, and human exposure risk in a transit-station lake for water diversion in east China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 311:119985. [PMID: 35985438 DOI: 10.1016/j.envpol.2022.119985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 07/27/2022] [Accepted: 08/13/2022] [Indexed: 06/15/2023]
Abstract
Quinolone antibiotics (QNs) pollution in lake environments is increasingly raising public concern due to their potential combined toxicity and associated risks. However, the spatiotemporal distribution and trophodynamics of QNs in transit-station lakes for water diversion are not well documented or understood. In this study, a comprehensive investigation of QNs in water, sediment, and aquatic fauna, including norfloxacin (NOR), ciprofloxacin (CIP), enrofloxacin (ENR), and ofloxacin (OFL), was conducted in Luoma Lake, a major transit station for the eastern route of the South-to-North Water Diversion Project in China. The target QNs were widely distributed in the water (∑QNs: 70.12 ± 62.79 ng/L) and sediment samples (∑QNs: 13.35 ± 10.78 ng/g dw) in both the non-diversion period (NDP) and the diversion period (DP), where NOR and ENR were predominant. All the QNs were detected in all biotic samples in DP (∑QNs: 80.04 ± 20.59 ng/g dw). The concentration of ∑QNs in the water in NDP was significantly higher than those in DP, whereas the concentration in the sediments in NDP was comparable to those in DP. ∑QNs in the water-sediment system exhibited decreasing trends from northwest (NW) to southeast (SE) in both periods; however, the Koc (organic carbon normalized partition coefficients) of individual QNs in DP sharply rose compared with those in NDP, which indicated that water diversion would alter the environmental fate of QNs in Luoma Lake. In DP, all QNs, excluding NOR, were all biodiluted across the food web; whereas their bioaccumulation potentials in the SE subregion were higher than those in the NW subregion, which was in contrast to the spatial distribution of their exposure concentrations. The estimated daily QN intakes via drinking water and aquatic products suggested that residents in the SE side were exposed to greater health risks, despite less aquatic pollution in the region.
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Affiliation(s)
- Yuanyuan Liu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai University, Nanjing, 210098, PR China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing, 210098, PR China
| | - Zulin Hua
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai University, Nanjing, 210098, PR China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing, 210098, PR China
| | - Ying Lu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai University, Nanjing, 210098, PR China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing, 210098, PR China
| | - Li Gu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai University, Nanjing, 210098, PR China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing, 210098, PR China
| | - Chengmei Luan
- Jiangsu Province Hydrology and Water Resources Investigation Bureau, Nanjing, 210098, PR China
| | - Xiaoqing Li
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai University, Nanjing, 210098, PR China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing, 210098, PR China
| | - Jianyi Wu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai University, Nanjing, 210098, PR China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing, 210098, PR China
| | - Kejian Chu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai University, Nanjing, 210098, PR China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing, 210098, PR China.
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Sun H, Chen T, Zhang L, Dong D, Li Y, Guo Z. Distribution of florfenicol and norfloxacin in ice during water freezing process: Dual effects by fluorine substituents. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 311:119921. [PMID: 35973450 DOI: 10.1016/j.envpol.2022.119921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/16/2022] [Accepted: 08/04/2022] [Indexed: 06/15/2023]
Abstract
Distribution in ice is regarded as one of important transport modes for pollutants in seasonal freeze-up waters in cold regions. However, the distribution characteristics and mechanisms of fluorinated antibiotics as emerging contaminants during the water freezing process remain unclear. Here, florfenicol and norfloxacin were selected as model fluorinated antibiotics to investigate their ice-water distribution. Effects of antibiotic molecular structure on the distribution were explored through comparative studies with their non-fluorinated structural analogs. Results showed that phase changes during the ice growth process redistributed the antibiotics, with antibiotic concentrations in water 3.0-6.4 times higher than those in ice. The solute-rich boundary layer with a concentration gradient was presented at the ice-water interface and controlled by constitutional supercooling during the freezing process. The ice-water distribution coefficient (KIW) values of antibiotics increased by 34.8%-38.0% with a doubling of the cooling area. The solute distribution coefficient (Kbs) values of antibiotics at -20 °C were 65.6%-70.3% higher than at -10 °C. The KIW and Kbs values of all antibiotics were negatively correlated with their water solubilities. The fluorine substituents influenced the binding energies between antibiotics and ice, resulting in a 1.1-fold increase in the binding energy of norfloxacin on the ice surface relative to its structural analog pipemidic acid. The results provide a new insight into the transport behaviors of fluorinated pharmaceuticals in ice-water systems.
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Affiliation(s)
- Heyang Sun
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130012, China
| | - Tianyi Chen
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130012, China; Housing and Urban-Rural Construction Bureau of Chengde High-Tech Industrial Development Zone, Chengde, 067000, China
| | - Liwen Zhang
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130012, China
| | - Deming Dong
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130012, China
| | - Yanchun Li
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun, 130023, China
| | - Zhiyong Guo
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130012, China.
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Zhang L, Du S, Liu D, Dong D, Zhang W, Guo Z. Antibiotics in fish caught from ice-sealed waters: Spatial and species variations, tissue distribution, bioaccumulation, and human health risk. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 821:153354. [PMID: 35085643 DOI: 10.1016/j.scitotenv.2022.153354] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 01/18/2022] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Antibiotics are increasingly detected in fish caught in ice-free waters, but information on fish caught in ice-sealed waters is insufficient. The concentrations of 23 antibiotics in the gills, muscles, kidneys, livers, biles, and brains of Cyprinus carpio and Hypophthalmichthys nobilis caught during winter fish-hunting activities in Chagan Lake, Haernao Reservoir, and Shitoukoumen Reservoir were systematically studied to ascertain the variations among fish species and fishing regions, tissue distribution, and bioaccumulation, as well as the potential risk to humans via the consumption of contaminated fish. The results indicated that the individual antibiotic concentration in tissues ranged from undetectable to 35.0 ng/g ww. The total antibiotic concentration in fish muscles from Shitoukoumen Reservoir was lower than that from Chagan Lake and Haernao Reservoir, but showed no significant difference between Cyprinus carpio and Hypophthalmichthys nobilis. Chloramphenicols had a high proportion in most fish tissues ranging from 28.3% to 44.0%, and the antibiotics were mainly distributed in the livers with a total concentration of 54.8 ± 9.9 ng/g ww. The mean values of bioaccumulation factors (BAF) of antibiotics in tissues ranged from 79.4 to 1000 L/kg, with the higher values found in the fish livers. The hazard quotient and hazard index value of antibiotics in the muscles of fish from ice-sealed were less than 1, indicating a negligible risk to human health via the consumption of fish muscles. This study revealed that the total antibiotic concentration in muscles showed spatial variations but not fish species-dependence. The antibiotics mainly accumulated in the livers. In addition, the target antibiotic concentrations in the muscles of fish from ice-sealed waters met the safe for consumption criteria.
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Affiliation(s)
- Liwen Zhang
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China
| | - Siying Du
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China; State Grid Sichuan Economic Research Institute, Chengdu 610041, China
| | - Deping Liu
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China
| | - Deming Dong
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China
| | - Wenming Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Zhiyong Guo
- Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China.
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Zhang Y, Jiang W, Dong H, Hu X, Fang B, Gao G, Zhao R. Study on the Electrochemical Removal Mechanism of Oxytetracycline by a Ti/IrO 2-Ta 2O 5 Plate. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18041708. [PMID: 33578856 PMCID: PMC7916611 DOI: 10.3390/ijerph18041708] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/02/2021] [Accepted: 02/06/2021] [Indexed: 11/16/2022]
Abstract
In this study, a Ti/IrO2-Ta2O5 anode was prepared by a hydrothermal method, and the prepared electrode was characterized by techniques such as scanning electron microscopy, X-ray diffraction, and electron dispersive spectroscopy. At the same time, the anode characteristics before and after electrochemical experiments were analyzed. The electrode gradation mechanism of oxytetracycline is discussed. In the whole experimental process, the range of electrolysis conditions was determined by single factor experiment, and then the optimal removal condition of oxytetracycline was determined by orthogonal experiments. The removal rate of oxytetracycline reached 99.02% after 20 min of electrolysis under the following optimal conditions: a current of 0.500 A, plate spacing of 2 cm, Na2SO4 electrolyte concentration of 4 g/L, and solution pH of 3. Additionally, the mechanism of oxytetracycline removal was explored, free radical scavenging experiments were performed, and the degradation mechanism was inferred based on the changes in the ultraviolet absorption of the oxytetracycline solution before and after electrolysis. Then, based on the liquid chromatography-mass spectrometry data, seven possible compounds and five possible removal pathways were proposed.
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