Seven popular fluoroquinolone antibiotics(FQs)in synthetic marine aquaculture water were subject to sodium hypochlorite(NaClO)disinfection scenario to investigate their reaction kinetics and transformation during chlo...Seven popular fluoroquinolone antibiotics(FQs)in synthetic marine aquaculture water were subject to sodium hypochlorite(NaClO)disinfection scenario to investigate their reaction kinetics and transformation during chlorination.Reactivity of each FQ to NaClO was following the order of ofloxacin(OFL)>enrofloxacin(ENR)>lomefloxacin(LOM)>ciprofloxacin(CIP)?norfloxacin(NOR)>>pipemedic acid(PIP),while flumequine did not exhibit reactivity.The coexisting chlorine ions and sulfate ions in the water slightly facilitated the oxidation of FQs by NaClO,while humic acid was inhibitable to their degradation.The bromide ions promoted degradation of CIP and LOM,but restrained oxidation of OFL and ENR.By analysis of liquid chromatography with tandem mass spectrometry(LC-MS/MS),eight kinds of emerging brominated disinfection byproducts(Br-DBPs)caused by FQ S were primarily identified in the chlorinated synthetic marine culture water.Through density functional theory calculation,the highest-occupied molecular orbital(HOMO)and the lowest-unoccupied molecular orbital(LUMO)characteristic as well as the charge distribution of the FQs were obtained to clarify transformation mechanisms.Their formation involved decarboxylation,ring-opening/closure,dealkylation and halogenation.Chlorine substitution occurred on the ortho-position of FQs's N4 and bromine substitution occurred on C8 position.The piperazine ring containing tertiary amine was comparatively stable,while this moiety with a secondary amine structure would break down during chlorination.Additionally,logK_(ow)and log BAF of transformation products were calculated by EPI-Suite^(TM)to analyze their bioaccumulation.The values indicated that Br-DBPs are easier to accumulate in the aquatic organism relative to their chloro-analogues and parent compounds.展开更多
The use of chemical disinfectants inactivates pathogens,but it also leads to the formation of disinfection byproducts(DBPs).Brominated disinfection byproducts(Br-DBPs)exhibit a high level of toxicity,so a comprehensiv...The use of chemical disinfectants inactivates pathogens,but it also leads to the formation of disinfection byproducts(DBPs).Brominated disinfection byproducts(Br-DBPs)exhibit a high level of toxicity,so a comprehensive understanding of their generation,toxicity and control strategies is needed.This study examines the research papers covering bromide concentrations in surface water,groundwater,or wastewater,involving 380 sampling sites.Additionally,the cytotoxicity,genotoxicity and developmental toxicity of Br-DBPs are summarized.The formation mechanisms of Br-DBPs in ozonation,chlorine-based,and persulfate-based disinfection processes are summarized,and an evaluation of control strategies for Br-DBPs and their associated toxicity is provided.The concentrations of bromide in surface water,groundwater,and wastewater in coastal areas are generally higher than those in inland areas,which are also affected by climate,topography,and the source of water.The toxicity of different types of Br-DBPs is different.The elevation of bromide concentration enhances the water toxicity,particularly in relation to ozonation.The introduction of 1000μg/L bromide results in a 3.06-fold increase in cytotoxicity and a 4.72-fold increase in genotoxicity.Hydrogen peroxide(H_(2)O_(2))and ammonia(NH_(3)-N)exhibit effective bromate control,but H_(2)O_(2)demonstrates limits efficacy in controlling Br-DBPs,while NH_(3)-N poses the risk of increased toxicity,up to a 2.86-fold increase in genotoxicity.Ultraviolet/ozone(UV/O3)and Ultraviolet/persulfate(UV/PS)can effectively control BrDBPs and toxicity but may promote bromate generation.This review will deepen the understanding of Br-DBPs and their toxicity generation behavior,thereby contributing to the further optimization and development of processes for Br-DBPs control.展开更多
基金supported by the National Natural Science Foundation of China(No.51668005)the Open fund of Guangxi Key Laboratory of Clean Pulp&Papermaking and Pollution Control(No.KF201719)+3 种基金the Innovation Project of Guangxi-Graduate Education(No.YCSW2019029)the Natural Science Foundation of Guangxi Province(No.2020GXNSFAA159135)the Ba Gui Scholars Program Foundation(2014)supported by the State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources。
文摘Seven popular fluoroquinolone antibiotics(FQs)in synthetic marine aquaculture water were subject to sodium hypochlorite(NaClO)disinfection scenario to investigate their reaction kinetics and transformation during chlorination.Reactivity of each FQ to NaClO was following the order of ofloxacin(OFL)>enrofloxacin(ENR)>lomefloxacin(LOM)>ciprofloxacin(CIP)?norfloxacin(NOR)>>pipemedic acid(PIP),while flumequine did not exhibit reactivity.The coexisting chlorine ions and sulfate ions in the water slightly facilitated the oxidation of FQs by NaClO,while humic acid was inhibitable to their degradation.The bromide ions promoted degradation of CIP and LOM,but restrained oxidation of OFL and ENR.By analysis of liquid chromatography with tandem mass spectrometry(LC-MS/MS),eight kinds of emerging brominated disinfection byproducts(Br-DBPs)caused by FQ S were primarily identified in the chlorinated synthetic marine culture water.Through density functional theory calculation,the highest-occupied molecular orbital(HOMO)and the lowest-unoccupied molecular orbital(LUMO)characteristic as well as the charge distribution of the FQs were obtained to clarify transformation mechanisms.Their formation involved decarboxylation,ring-opening/closure,dealkylation and halogenation.Chlorine substitution occurred on the ortho-position of FQs's N4 and bromine substitution occurred on C8 position.The piperazine ring containing tertiary amine was comparatively stable,while this moiety with a secondary amine structure would break down during chlorination.Additionally,logK_(ow)and log BAF of transformation products were calculated by EPI-Suite^(TM)to analyze their bioaccumulation.The values indicated that Br-DBPs are easier to accumulate in the aquatic organism relative to their chloro-analogues and parent compounds.
基金supported by National Natural Science Foundation of China(No.52170044)Technology Innovation Research and Development Project of Chengdu Science and Technology Bureau(China)(No.2024-YF05-01366-SN).
文摘The use of chemical disinfectants inactivates pathogens,but it also leads to the formation of disinfection byproducts(DBPs).Brominated disinfection byproducts(Br-DBPs)exhibit a high level of toxicity,so a comprehensive understanding of their generation,toxicity and control strategies is needed.This study examines the research papers covering bromide concentrations in surface water,groundwater,or wastewater,involving 380 sampling sites.Additionally,the cytotoxicity,genotoxicity and developmental toxicity of Br-DBPs are summarized.The formation mechanisms of Br-DBPs in ozonation,chlorine-based,and persulfate-based disinfection processes are summarized,and an evaluation of control strategies for Br-DBPs and their associated toxicity is provided.The concentrations of bromide in surface water,groundwater,and wastewater in coastal areas are generally higher than those in inland areas,which are also affected by climate,topography,and the source of water.The toxicity of different types of Br-DBPs is different.The elevation of bromide concentration enhances the water toxicity,particularly in relation to ozonation.The introduction of 1000μg/L bromide results in a 3.06-fold increase in cytotoxicity and a 4.72-fold increase in genotoxicity.Hydrogen peroxide(H_(2)O_(2))and ammonia(NH_(3)-N)exhibit effective bromate control,but H_(2)O_(2)demonstrates limits efficacy in controlling Br-DBPs,while NH_(3)-N poses the risk of increased toxicity,up to a 2.86-fold increase in genotoxicity.Ultraviolet/ozone(UV/O3)and Ultraviolet/persulfate(UV/PS)can effectively control BrDBPs and toxicity but may promote bromate generation.This review will deepen the understanding of Br-DBPs and their toxicity generation behavior,thereby contributing to the further optimization and development of processes for Br-DBPs control.
