{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T14:28:12Z","timestamp":1785421692789,"version":"3.56.0"},"reference-count":32,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T00:00:00Z","timestamp":1779408000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004731","name":"Zhejiang Provincial Natural Science Foundation","doi-asserted-by":"publisher","award":["LGF22E080027"],"award-info":[{"award-number":["LGF22E080027"]}],"id":[{"id":"10.13039\/501100004731","id-type":"DOI","asserted-by":"publisher"}]},{"award":["LGF22E080027"],"award-info":[{"award-number":["LGF22E080027"]}],"id":[{"id":"https:\/\/ror.org\/04aqat463","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Competitive Projects in Science and Technology Programmes of Quzhou","award":["2023K052 and 2023K227"],"award-info":[{"award-number":["2023K052 and 2023K227"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxics"],"abstract":"<jats:p>Neonicotinoid pesticides are a typical category of emerging hazardous micropollutants, and chlorine (Cl2) is a widely used disinfectant that readily induces the chlorination of organic micropollutants. This study systematically investigated the chlorination kinetics and transformation pathways of a representative neonicotinoid pesticide (clothianidin, CLO) and evaluated the cytotoxicity variation via Chinese Hamster Ovary (CHO) cell assays. CLO chlorination followed second-order kinetics, with a first-order dependence on both CLO and Cl2 concentrations, and the apparent rate constant (kapp) value was measured to be 1.758 \u00d7 10\u22124 \u03bcM\u22121 h\u22121, at a pH of 7.0. The CLO chlorination initially accelerated and then retarded with the increase in pH. The same tendency was involved in the yield of disinfection byproducts (i.e., trihalomethanes and haloacetic acids). Dissolved organic matter was also a crucial factor inhibiting the chlorination of CLO. The reaction of CLO+ with HOCl was more prevalent than between CLO+ with ClO\u2212, wherein HOCl likely exerts electrophilic attack either after 2-nitroguanidine hydrolysis or directly at the nitrogen sites of secondary amines. Cell exposure results revealed that the chronic cytotoxicity of CLO decreased significantly after chlorination. This study helps to the mechanistic understanding of neonicotinoid transformation during water disinfection, and provides a valuable reference for the control of neonicotinoid pesticides in drinking water.<\/jats:p>","DOI":"10.3390\/toxics14060453","type":"journal-article","created":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T16:06:08Z","timestamp":1779465968000},"page":"453","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Chlorination of Clothianidin During Disinfection: Kinetics, Pathways, and Toxicity"],"prefix":"10.3390","volume":"14","author":[{"given":"Fang","family":"Wei","sequence":"first","affiliation":[{"name":"Department of Hydraulic Engineering, Zhejiang Tongji Vocational College of Science and Technology, Hangzhou 310000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lei","family":"Wu","sequence":"additional","affiliation":[{"name":"Longyou Inspection & Testing Research Institute, Quzhou 324000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fei","family":"Meng","sequence":"additional","affiliation":[{"name":"Zhejiang Yilong Environmental Protection Technology Co., Ltd., Hangzhou 310000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sanyan","family":"Du","sequence":"additional","affiliation":[{"name":"Yangtze River Delta Institute of Health Agriculture (Zhejiang) Co., Ltd., Jiaxing 314000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyuan","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Environment, Zhejiang University of Technology, Hangzhou 310000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Hu","sequence":"additional","affiliation":[{"name":"College of Environment, Zhejiang University of Technology, Hangzhou 310000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2897","DOI":"10.1021\/jf101303g","article-title":"Overview of the Status and Global Strategy for Neonicotinoids","volume":"59","author":"Jeschke","year":"2010","journal-title":"J. Agric. Food Chem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1584\/jpestics.D12-037","article-title":"Overall status of neonicotinoid insecticides in China: Production, application and innovation","volume":"38","author":"Shao","year":"2013","journal-title":"J. Pestic. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"115975","DOI":"10.1016\/j.watres.2020.115975","article-title":"Heterogeneous electro\u2013Fenton using three\u2013dimension NZVI\u2013BC electrodes for degradation of neonicotinoid wastewater","volume":"182","author":"Zhang","year":"2020","journal-title":"Water Res."},{"key":"ref_4","first-page":"15\u201319","article-title":"Dust in the wind\u2014Drift of dust containing insecticides\u2014A risk for honey bees (Apis mellifera L.)?","volume":"430","author":"Georgiadis","year":"2011","journal-title":"Nat. Preced."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1016\/j.envpol.2017.03.084","article-title":"Ornamental plants on sale to the public are a significant source of pesticide residues with implications for the health of pollinating insects","volume":"228","author":"Lentola","year":"2017","journal-title":"Environ. Pollut."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"114777","DOI":"10.1016\/j.taap.2019.114777","article-title":"Growth and neurite stimulating effects of the neonicotinoid pesticide clothianidin on human neuroblastoma SH-SY5Y cells","volume":"383","author":"Hirano","year":"2019","journal-title":"Toxicol. Appl. Pharmacol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"120863","DOI":"10.1016\/j.watres.2023.120863","article-title":"Identification of point and nonpoint emission sources of neonicotinoid pollution in regional surface water","volume":"248","author":"Chen","year":"2024","journal-title":"Water Res."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"168","DOI":"10.1021\/acs.estlett.7b00081","article-title":"Occurrence of Neonicotinoid Insecticides in Finished Drinking Water and Fate during Drinking Water Treatment","volume":"4","author":"Klarich","year":"2017","journal-title":"Environ. Sci. Technol. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1022","DOI":"10.1016\/j.envpol.2018.01.013","article-title":"Year-round presence of neonicotinoid insecticides in tributaries to the Great Lakes, USA","volume":"235","author":"Hladik","year":"2018","journal-title":"Environ. Pollut."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"116630","DOI":"10.1016\/j.watres.2020.116630","article-title":"A nationwide study of occurrence and exposure assessment of neonicotinoid insecticides and their metabolites in drinking water of China","volume":"189","author":"Mahai","year":"2021","journal-title":"Water Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"506","DOI":"10.1016\/j.chemosphere.2018.02.108","article-title":"Neonicotinoid pesticides in drinking water in agricultural regions of southern Ontario, Canada","volume":"202","author":"Sultana","year":"2018","journal-title":"Chemosphere"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"513","DOI":"10.1016\/j.scitotenv.2019.04.267","article-title":"Neonicotinoids in raw, finished, and tap water from Wuhan, Central China: Assessment of human exposure potential","volume":"675","author":"Wan","year":"2019","journal-title":"Sci. Total Environ."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"117767","DOI":"10.1016\/j.envpol.2021.117767","article-title":"Concentrations and distributions of neonicotinoids in drinking water treatment plants in South Korea","volume":"288","author":"Kim","year":"2021","journal-title":"Environ. Pollut."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2644","DOI":"10.1021\/acsestwater.4c00148","article-title":"Distribution and Health Risk Assessment of Neonicotinoid Insecticides in Drinking Water of Major River Basins in China","volume":"4","author":"Chen","year":"2024","journal-title":"ACS ES&T Water"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"123159","DOI":"10.1016\/j.jclepro.2020.123159","article-title":"Chlorination disinfection by-products in municipal drinking water\u2014A review","volume":"273","author":"Mazhar","year":"2020","journal-title":"J. Clean. Prod."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/j.watres.2007.07.025","article-title":"Reactions of chlorine with inorganic and organic compounds during water treatment\u2014Kinetics and mechanisms: A critical review","volume":"42","author":"Deborde","year":"2008","journal-title":"Water Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1016\/j.watres.2009.11.045","article-title":"Oxidative transformation of micropollutants during municipal wastewater treatment: Comparison of kinetic aspects of selective (chlorine, chlorine dioxide, ferrateVI, and ozone) and non-selective oxidants (hydroxyl radical)","volume":"44","author":"Lee","year":"2010","journal-title":"Water Res."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"704","DOI":"10.1021\/acs.est.3c05978","article-title":"Chlorination of Emerging Contaminants for Application in Potable Wastewater Reuse: Disinfection Byproduct Formation, Estrogen Activity, and Cytotoxicity","volume":"58","author":"Cochran","year":"2023","journal-title":"Environ. Sci. Technol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"140476","DOI":"10.1016\/j.cej.2022.140476","article-title":"Disinfection byproducts formation from emerging organic micropollutants during chlorine-based disinfection processes","volume":"455","author":"Shao","year":"2023","journal-title":"Chem. Eng. J."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"119449","DOI":"10.1016\/j.watres.2022.119449","article-title":"Overlooked roles of Cl2O and Cl2 in micropollutant abatement and DBP formation by chlorination","volume":"229","author":"Yang","year":"2023","journal-title":"Water Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"120794","DOI":"10.1016\/j.watres.2023.120794","article-title":"Developing a hybrid model for predicting the reaction kinetics between chlorine and micropollutants in water","volume":"247","author":"Zhao","year":"2023","journal-title":"Water Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1021\/acs.estlett.8b00706","article-title":"Chlorinated Byproducts of Neonicotinoids and Their Metabolites: An Unrecognized Human Exposure Potential?","volume":"6","author":"Webb","year":"2019","journal-title":"Environ. Sci. Technol. Lett."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"118318","DOI":"10.1016\/j.watres.2022.118318","article-title":"Metabonomic and transcriptomic modulations of HepG2 cells induced by the CuO-catalyzed formation of disinfection byproducts from biofilm extracellular polymeric substances in copper pipes","volume":"216","author":"Hu","year":"2022","journal-title":"Water Res."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Mulligan, R.A. (2015). Environmental Fate of Clothianidin Under Simulated California Rice Field Conditions, University of California.","DOI":"10.1002\/ps.4150"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2920","DOI":"10.1021\/es026230q","article-title":"Factors influencing the formation and relative distribution of haloacetic acids and trihalomethanes in drinking water","volume":"37","author":"Liang","year":"2003","journal-title":"Environ. Sci. Technol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"141117","DOI":"10.1016\/j.chemosphere.2024.141117","article-title":"N-dealkylation of amines during water disinfection\u2014Revealing a new direction in the formation of disinfection by-products","volume":"350","author":"Mazur","year":"2024","journal-title":"Chemosphere"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"169235","DOI":"10.1016\/j.cej.2025.169235","article-title":"Chlorination of neonicotinoid pesticides: pH-dependent kinetics, reaction pathways, and toxicity assessment","volume":"524","author":"Song","year":"2025","journal-title":"Chem. Eng. J."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"132444","DOI":"10.1016\/j.cej.2021.132444","article-title":"pH-dependent contribution of chlorine monoxide radicals and byproducts formation during UV\/chlorine treatment on clothianidin","volume":"428","author":"Lee","year":"2022","journal-title":"Chem. Eng. J."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2797","DOI":"10.1002\/etc.4256","article-title":"Neonicotinoid insecticide hydrolysis and photolysis: Rates and residual toxicity","volume":"37","author":"Todey","year":"2018","journal-title":"Environ. Toxicol. Chem."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1371","DOI":"10.1134\/S1061934819140077","article-title":"Photocatalytic Degradation of Chlothianidin: Effect of Humic Acids, Nitrates, and Oxygen","volume":"74","author":"Kralj","year":"2019","journal-title":"J. Anal. Chem."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1653","DOI":"10.1002\/rcm.7581","article-title":"Nitenpyram degradation in finished drinking water","volume":"30","author":"Noestheden","year":"2016","journal-title":"Rapid Commun. Mass Spectrom."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"22790\u201322798","DOI":"10.1021\/acs.est.4c09683","article-title":"First evidence of novel organothiophosphate esters as prevalent new pollutants in dust from automotive repair shops discovered by high-resolution mass spectrometry","volume":"58","author":"Feng","year":"2024","journal-title":"Environ. Sci. Technol."}],"container-title":["Toxics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2305-6304\/14\/6\/453\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T04:15:34Z","timestamp":1780546534000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2305-6304\/14\/6\/453"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,22]]},"references-count":32,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["toxics14060453"],"URL":"https:\/\/doi.org\/10.3390\/toxics14060453","relation":{},"ISSN":["2305-6304"],"issn-type":[{"value":"2305-6304","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,22]]}}}