The potential threats of polycyclic aromatic hydrocarbons(PAHs)and chlorinated/brominated PAHs(Cl/Br-PAHs)to human health from particulate matter in the urban ambient air were studied using human health risk assessmen...The potential threats of polycyclic aromatic hydrocarbons(PAHs)and chlorinated/brominated PAHs(Cl/Br-PAHs)to human health from particulate matter in the urban ambient air were studied using human health risk assessments.The risk to human health caused by exposure to PAHs was evaluated in Shijiazhuang,China,from January to December 2018.The PAHs concentration range was 16.02e475.21 ng/m3 and the toxic equivalent was 13.605 ng/m3.For adults,the average carcinogenic risk caused by respiratory exposure was 5.163×10^-6 and the resulting loss of life expectancy was 32.10 min.The human health risks of respiratory exposure to Cl/Br-PAHs in atmospheric samples from the Haidian District,Beijing,China,were evaluated from November 2017 to July 2018.The concentration ranges for the Cl-and Br-PAHs were 60.38e482.17 pg/m3 and 1.32e25.35 pg/m3,respectively.The average carcinogenic equivalent concentrations were 0.3274 pg/m3 and 0.0061 pg/m3 for the Cl-and Br-PAHs,respectively.For adults the average carcinogenic risks caused by respiratory exposure were 1.243×10^-10 and 2.316×10^-12 for the Cl-and Br-PAHs,respectively.The resulting loss of life expectancy values were 0.001 min(Cl-PAHs)and 0.00 min(Br-PAHs).The pollution concentrations and toxic equivalents of the Cl/Br-PAHs in Beijing and of the PAHs in Shijiazhuang both showed toxicity was high in the winter.The average carcinogenic risk for exposure of adults to PAHs in Shijiazhuang was low with certain potential hazards.The concentration of Cl-PAHs in Beijing was higher than that of Br-PAHs,and the average carcinogenic risk for exposure of adults to Cl/Br-PAHs was very low with slight harm.展开更多
The brominated products, formed in chlorination treatment of benzophenone-4 in the presence of bromide ions, were identified, and the formation pathways were proposed.Under disinfection conditions, benzophenone-4 woul...The brominated products, formed in chlorination treatment of benzophenone-4 in the presence of bromide ions, were identified, and the formation pathways were proposed.Under disinfection conditions, benzophenone-4 would undertake electrophilic substitution generating mono- or di-halogenated products, which would be oxidized to esters and further hydrolyzed to phenol derivatives. The generated catechol intermediate would be transformed into furan-like heterocyclic product. The product species were p H-dependent,while benzophenone-4 elimination was chlorine dose-dependent. When the chlorination treatment was performed on ambient water spiked with benzophenone-4 and bromide ions, most of brominated byproducts could be detected, and the acute toxicity significantly increased as well.展开更多
The formation of brominated trihalomethanes (THMs-Br) which is proved more carcinogenic than their chlorinated analogues reported was very different at various water qualities.This study was performed to assess the ef...The formation of brominated trihalomethanes (THMs-Br) which is proved more carcinogenic than their chlorinated analogues reported was very different at various water qualities.This study was performed to assess the effects of water quality parameters (bromide concentration,pH value and ammonia concentration),chlorination conditions (chlorine dose,reaction time) and ratios of Br-/DOC and Br-/Cl2 consumption on the formation and distribution of THMs-Br in chlorination.The results showed good correlation between the bromine incorporation factor (BIF) n(Br) and Br-/Cl2 consumption ratio.The formation of total THM (TTHM) was found to decrease with increasing ammonia concentration but to increase with bromide concentration and pH value.The n(Br) trends were significantly affected by the presence of bromide concentration.The effects on the molar yields of THMs were more strongly influenced by bromide concentration and dissolved organic carbon (DOC) concentration than pH value and natural organic matter (NOM) source.High Br-/DOC and Br-/Cl2 favor the formation of THMs-Br over chlorinated THMs (THMs-Cl).The experimental data including the main parameters such as bromide,DOC,ammonia,pH and reaction time were used for developing the predictive model for THMs-Br.展开更多
Brominated flame retardants(BFRs),have been extensively utilized in modern industry,contaminate aquatic ecosystems.They exhibit bioaccumulation and biomagnification properties,posing significant risks to human health,...Brominated flame retardants(BFRs),have been extensively utilized in modern industry,contaminate aquatic ecosystems.They exhibit bioaccumulation and biomagnification properties,posing significant risks to human health,such as developmental disorders,endocrine disruption,and other adverse effects.Current treatment methods for BFRs encompass chemical,electrochemical,biological,and advanced oxidation processes(AOPs).Among them,AOPs are particularly notable for their stability,ease of control,and production of clean end-products.This paper focuses on employing a titanium dioxide(TiO_(2))photocatalytic system to investigate the degradation of 2,4,6-tribromophenol(TBP).展开更多
Currently,ferrate(VI)oxidation technology(FOT)has been regarded as one of the most promising options for the degradation of emerging organic pollutants.However,the role and transformation of chloride ions(Cl^(−))in FO...Currently,ferrate(VI)oxidation technology(FOT)has been regarded as one of the most promising options for the degradation of emerging organic pollutants.However,the role and transformation of chloride ions(Cl^(−))in FOT have not been well explored.The current study aims to investigate the formation of chlorinated phenolic byproducts upon ferrate(VI)oxidation processes.The obtained results indicate that chlorides suffering ferrate(VI)attack will be transformed to active chlorine species(ACS),which will subsequently lead to the formation of highly toxic aromatic chlorinated byproducts.The identified byproducts include common chlorinated phenolic derivatives,as well as complex chlorinated oligomer byproducts with ether structures(mainly dimers and trimers).While the formation of common chlorophenols can be ascribed to the electrophilic substitution reactions mediated by ACS,the oligomer byproducts are generated via coupling reactions between chlorinated phenoxy radicals.ECOSAR software predicts that the generated chlorinated oligomer byproducts exhibit high ecotoxicological effects.As a whole,the above findings shed light on the potential risk of FOT in real practice.展开更多
Objectives:Photodynamic therapy(PDT)is a minimally invasive method used in the treatment of various cancers and skin diseases,but it is not widely used in bone cancer,where the current therapy is often not effective a...Objectives:Photodynamic therapy(PDT)is a minimally invasive method used in the treatment of various cancers and skin diseases,but it is not widely used in bone cancer,where the current therapy is often not effective and accompanied by side effects.Alternative and more effective therapies like PDT are needed.In this in-vitro study,the effect of the photosensitizer(PS)chlorin e6(Ce6)on cancerous bone tumor cells using PDT was examined.Methods:A total of 27 tissue specimens from patients with primary bone cancers or bone metastases of different origins were genetically characterized and treated with PDT.Following a 24-h incubation,cell viability was determined,and the effect of PDT on cell migration was analyzed over 48 h.Results:We could demonstrate that the effect on proliferation of PDT in combination with the PS Ce6 was best in cells isolated from primary osteosarcoma and in bone metastases from mammary carcinomas.Besides proliferation,PDT was also effective in inhibiting the migration of these cells.A statistically significant correlation between the PDT effect and CD164 gene expression was detected,indicating that a high expression of this gene could result in a higher effectiveness of the photodynamic treatment.Conclusion:This study analyzes for the first time the effect of PDT in bone cancers and metastases and shows the potential of treating these cancer types with Ce6 PDT.展开更多
A method was developed for determination of chlorine and bromine in plant materials by ion chromatography using temperature programing-semi molten for sample preparation. Values of detection limits of the method found...A method was developed for determination of chlorine and bromine in plant materials by ion chromatography using temperature programing-semi molten for sample preparation. Values of detection limits of the method found were 1.0×10^-5 for CI and 1.3×10^-6 for Br. The measuring range of the method found were 0.3-20.0 mg/L for CI and 4,0-120,0 μg/L for Br. The results obtained agreed quite well with those reference values.展开更多
This review summarizes the environmental levels,toxicity effects and analytical development of Tris(2,3-dibromopropyl)Isocyanurate(TBC).Further study is required on the environmental behavior of TBC,mechanism of toxic...This review summarizes the environmental levels,toxicity effects and analytical development of Tris(2,3-dibromopropyl)Isocyanurate(TBC).Further study is required on the environmental behavior of TBC,mechanism of toxicity and alternative development.展开更多
Accelerated industrialization and urbanization,and unregulated disposal of waste of electric and electronic equipment（e-waste） in China have caused environmental pollution of brominated flame retardants（BFRs）.This...Accelerated industrialization and urbanization,and unregulated disposal of waste of electric and electronic equipment（e-waste） in China have caused environmental pollution of brominated flame retardants（BFRs）.This review summarized the levels,trends,and bioaccumulation characteristics of polybrominated diphenyl ethers（PBDEs） and other potential alternative BFRs including hexabromocyclododecanes（HBCDs）,1,2-bis（2,4,6-dibromophenoxy） ethane（BTBPE） and decabromodiphenylethane（DBDPE） in wildlife from China.PBDE levels in wildlife from China were generally higher than those from other parts in Asia,and were comparable to those from Europe but were lower than those from North America.However,wildlife from the e-waste recycling sites in South China and East China contained much higher PBDEs compared to other reports around the world,suggesting the heavy contamination of PBDEs in these regions.The alternative BFRs were also detected in wildlife,revealing that the animals are exposed to these chemicals,in addition to PBDEs.Temporal trends indicated by levels in marine mammals from South China suggested that PBDE levels increased from the beginning of 1990s to 2000s,but decreased from the middle of 2000s,followed by relatively steady levels.In contrast,HBCDs were found to be continuously increasing from 1997 to 2007,indicating the increasing usage of HBCDs in China in recent years.Compared to PBDE profiles found in other parts,aquatic species and birds from China contained relatively higher contributions of BDE28 and 209,respectively,suggesting the possible different usage pattern of PBDEs.Future works including keeping monitoring at a reasonable scale and frequency to make sure levels near urban centers indicative of population do not increase are needed.Additionally,focus effort on e-waste recycling regions to look for impacts and to determine if regulation/controls are resulting in lower environmental contamination,and incorporation of sentinel species in monitoring efforts are recommended.展开更多
This study reports the presence of brominated flame retardants in the topsoil in and around Harbin, a city in northeastern China. Samples of soil were collected from 17 locations in 2006, and the levels of 9 polybromi...This study reports the presence of brominated flame retardants in the topsoil in and around Harbin, a city in northeastern China. Samples of soil were collected from 17 locations in 2006, and the levels of 9 polybrominated diphenylethers （PBDEs 17, 28, 47, 66, 99, 100, 153, 154, and 183） ranged from 2.45 to 55.9 pg/g dry weight （dw） with a mean of 26.3 pg/g dw. These levels are very low comparing with those for some cities in Europe and USA. BDE 209 and hexabromocyclododecane were the two dominant congeners, with mean concentrations of 520 pg/g dw and 1750 pg/g dw, respectively. The concentrations of the total nine PBDE congeners clearly decreased from urban areas to background, but the compositions of individual congeners differed. Proportions of heavier congeners decreased while those of lighter congeners increased, along urban-rural-background transect, providing evidence for an urban fractionation effect. Correlation analysis indicated similar sources for PBDEs, hexabromocyclododecane, and 1,2-bis（2,4,6-tribromophenoxy）-ethane from urban areas but pentabromoethylbenzene was probably present due to long-range atmospheric transport. Principal component analysis was used to determine the characteristics of the relationships among these brominated flame retardants in the field.展开更多
Brominated phenols （BPs）, a widely used group of emerging flame retardants, are important environmental contaminants and exhibit endocrine disrupting potential. Method for simultaneous determination of tetrabromobis...Brominated phenols （BPs）, a widely used group of emerging flame retardants, are important environmental contaminants and exhibit endocrine disrupting potential. Method for simultaneous determination of tetrabromobisphenol A （TBBPA）, tribromophenol （TBP）, dibromophenols （DBPs） and monobromophenols （MBPs） in soils using gas chromatography-mass spectrometry analysis （GC/MS） was successfully developed. Cleanup methods for soil extracts including several solid-phase extraction cartridges and different elution solvents were compared and optimized. Florisil cartridge with dichloromethane as the elution reagent was selected for sample cleanup owing to its high and reproducible recoveries of the target analytes in soils. Derivatization conditions were tested and the optimal conditions were obtained with 20 μL silylation reagent at room temperature. The chromatographic separation was optimized with different columns and DB-XLB column was selected for its excellent separation of the analytes. The limits of detection for the target compounds were from 0.04 to 0.19 ng/g. Mean recoveries of the compounds from spiked soils exceeded 84% with a good reproducibility, excepting that the recovery of 2-bromophenol was relatively poor （lower than 55%） due to its instability. The developed method was applied to the determination of the BPs in the soils collected from e-waste sites. The contents of BPs in the soils were at ng/g levels with TBBPA and TBP the most frequently detected. To our knowledge, this is the first report for the simultaneous determination of TBBPA, TBP, DBPs and MBPs in soils.展开更多
Short-chain chlorinated paraffins(SCCPs) are produced in high volume and have the high potential to pose a threat to human health. However, little information is available for SCCP contamination in human blood/plasma/...Short-chain chlorinated paraffins(SCCPs) are produced in high volume and have the high potential to pose a threat to human health. However, little information is available for SCCP contamination in human blood/plasma/serum, mainly due to the difficulty of sample preparation and quantitative analysis. A method using high resolution gas chromatography coupled with electron capture negative ionization low resolution mass spectrometry(HRGC–ECNI/LRMS) was developed and validated to measure SCCPs in human plasma. The pretreatment process included protein denaturation and lipid elimination, liquid–liquid extraction with a mixture of n-hexane/dichloromethane(1:1, V/V), and cleanup on a multilayer silica column. The blank controls, including procedural blank, vacuum blood collection tube blank, and instrumental blank, were the most pivotal points for the reliable analysis of SCCPs. The average value of procedural blanks was 9.0 ng/g; and the method detection limit(MDL), calculated as the sum of the average procedural blank value and 3 times of the standard deviation of the procedural blanks, was 12.6 ng/g plasma. The validated method was applied to measure the concentrations of the total SCCPs(∑ SCCPs) in50 plasma samples from a general population. The measured plasma concentrations of ∑SCCPs ranged from <MDL to 203 ng/g wet weight(ww), with an average value of 32.0 ng/g ww.The relative abundance profiles of SCCPs in plasma samples were dominated by C10- and C11-CP congener groups centered on Cl6–7. The developed method can be used for the comprehensive and large-scale investigation of SCCP levels in human plasma.展开更多
A new brominated phenylpropylaldehyde and its dimethyl acetal together with a new natural brominated phenol were isolated from Rhodomela confervoides. Their structrues were elucidated as 2-methyl-3-(2,3-dibromo-4,5-di...A new brominated phenylpropylaldehyde and its dimethyl acetal together with a new natural brominated phenol were isolated from Rhodomela confervoides. Their structrues were elucidated as 2-methyl-3-(2,3-dibromo-4,5-dihydroxyphenyl)propylaldehyde, 2-methyl-3-(2,3-di-bromo-4,5-dihydroxyphenyl) propylaldehyde dimethyl acetal and 3-bromo-4,5-dihydroxybenzoic acid methyl ester by spectroscopic techniques including IR, HRFABMS, ID and 2DNMR experiments.展开更多
An efficient and mild protocol for bromination of aryl azides with N-bromosuccinimide（NBS） under FeCl_3 catalysis in 1,2- dichloroethane was developed.It is proved to be an efficient method for obtaining brominated ...An efficient and mild protocol for bromination of aryl azides with N-bromosuccinimide（NBS） under FeCl_3 catalysis in 1,2- dichloroethane was developed.It is proved to be an efficient method for obtaining brominated aryl azides.展开更多
Air samples were collected simultaneously at platform,mezzanine and outdoor in five typical stations of subway system in Shanghai,China using stainless steel canisters and analyzed by gas chromatography-mass selective...Air samples were collected simultaneously at platform,mezzanine and outdoor in five typical stations of subway system in Shanghai,China using stainless steel canisters and analyzed by gas chromatography-mass selective detector （GC-MSD） after cryogenic pre-concentration.Benzene,toluene,ethylbenzene and xylenes （BTEX） at the platforms and mezzanines inside the stations averaged （10.3±2.1）,（38.7±9.0）,（19.4±10.1） and （30.0±11.1） μg/m 3,respectively;while trichloroethylene （TrCE）,tetrachloroethylene （TeCE） and para-dichlorobenzene （pDCB）,vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of （3.6±1.3）,（1.3±0.5）,（4.1±1.1）,（2.2±1.1） and （1.2±0.3） μg/m 3,respectively.Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor （platforms and mezzanines） than outdoor with average indoor/outdoor （I/O） ratios of 1.1–9.5,whereas no significant indoor/outdoor differences were found except for benzene and TrCE.The highly significant mutual correlations （p0.01） for BTEX between indoor and outdoor and their significant correlation （p0.05） with methyl tert-butyl ether （MTBE）,a marker of traffic-related emission without other indoor and outdoor sources,indicated that BTEX were introduced into the subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source.TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air,especially in the mezzanines.展开更多
The effects of ozonation on the formation potential of typical disinfection byproducts （DBPs） and the changes of genotoxicity during post chlorination of tertiary effluent from a sewage treatment plant were investig...The effects of ozonation on the formation potential of typical disinfection byproducts （DBPs） and the changes of genotoxicity during post chlorination of tertiary effluent from a sewage treatment plant were investigated. Ozonation enhanced the yields of all detected chlorine DBPs except CHCI3. At a chlorine dose of 5 mg/L, the three brominated THMs and five HAAs increased, while chloroform decreased with the increase of ozone dose from 0 to 10 mg/L （ozone dose in consumption base）. At a chlorine dose of 10 mg/L, the two mixed bromochloro species THMs and two dominant HAAs （DCAA and TCAA） increased firstly and then decreased with the increase of ozone dose, with the turning point approximately occurring at an ozone dose of 5 mg/L. The genotoxicity detected using umu test, on the other hand, was removed from 7 Ixg 4-NQO/L to a negligible level by ozonation under an ozone dose of 5 mg/L. Chlorination could further remove the genotoxicity to some extent. It was found that SUVA （UV absorbance divided by DOC concentration） might be used as an indicative parameter for monitoring the removal of genotoxicity during the oxidation.展开更多
To elucidate the mechanism of brominated natural rubber(BNR), eight BNR samples with different bromine content were prepared from latex in different bromination time, and the microstructures were characterized by Four...To elucidate the mechanism of brominated natural rubber(BNR), eight BNR samples with different bromine content were prepared from latex in different bromination time, and the microstructures were characterized by Fourier transform infrared spectroscopy(FTIR) and ~1H-NMR spectroscopy, respectively. The hardness of BNR increased and its nature transformed from elastomer to resin with the increase of bromine content. Unlike chlorinated natural rubber(CNR), FTIR showed that there were no carbonyl groups on the molecular chains of BNR. ~1H-NMR spectroscopy revealed that the reaction activity of bromine and the secondary hydrogen atom of BNR were much higher than those of the primary one. The brominated substitution took place in the hydrogen atom of CH_3 and CH_2 groups firstly, then in the late period of bromination the bond of C=C was transferred to the saturated bond of C-C due to the Markovnikov addition of hydrogen bromide. Based on these findings, the mechanism of BNR from latex could be deduced as a free radical reaction and the detailed bromination process was presented.展开更多
Poly（propylene carbonate） （PPC）, the copolymerization product of carbon dioxide and propylene oxide, was chlorinated for the first time in our laboratory. Nuclear magnetic resonance （NMR） spectroscopy and ion ch...Poly（propylene carbonate） （PPC）, the copolymerization product of carbon dioxide and propylene oxide, was chlorinated for the first time in our laboratory. Nuclear magnetic resonance （NMR） spectroscopy and ion chromatography test showed that chlorine atoms were successfully introduced onto the polymer chains of PPC. We named this newborn polymer material as chlorinated poly（propylene carbonate） （CPPC）. It is worth noting that the reaction conditions of the chlorination of PPC were quite mild, which could be easily and simply realized at industrial level. What is more important is that CPPC possessed many more distinguished properties in solubility, wettability, adhesiveness, and gas barrier compared with PPC. For example, the bonding strength of CPPC as thermal adhesive is nearly four times higher than that of PPC for wood, stainless steel and glass. The oxygen permeability coefficient of CPPC exhibits a decrease of 33% compared with that of PPC. Moreover, CPPC is quite stable in air, whereas it could be well biodegraded in soil compared with PPC. These results indicated that CPPC could be widely used in the fields of coating, adhesive, barrier materials and so on, which could greatly promote the development of PPC industry.展开更多
Improving the performance and reducing the manufacturing costs are the main directions for the development of organic solar cells in the future.Here,the strategy that uses chemical structure modification to optimize t...Improving the performance and reducing the manufacturing costs are the main directions for the development of organic solar cells in the future.Here,the strategy that uses chemical structure modification to optimize the photoelectric properties is reported.A new narrow bandgap(1.30 eV)chlorinated non-fullerene electron acceptor(Y15),based on benzo[d][1,2,3] triazole with two 3-undecylthieno[2’,3’:4,5] thieno[3,2-b] pyrrole fused-7-heterocyclic ring,with absorption edge extending to the near-infrared(NIR) region,namely A-DA’D-A type structure,is designed and synthesized.Its electrochemical and optoelectronic properties are systematically investigated.Benefitting from its NIR light harvesting,the fabricated photovoltaic devices based on Y15 deliver a high power conversion efficiency(PCE) of 14.13%,when blending with a wide bandgap polymer donor PM6.Our results show that the A-DA’D-A type molecular design and application of near-infrared electron acceptors have the potential to further improve the PCE of polymer solar cells(PSCs).展开更多
The increasing production and usage of chlorinated paraffins(CPs) correspondently increase the amount of CPs that experience thermal processes. Our previous study revealed that a significant amount of medium-chain chl...The increasing production and usage of chlorinated paraffins(CPs) correspondently increase the amount of CPs that experience thermal processes. Our previous study revealed that a significant amount of medium-chain chlorinated paraffins(MCCPs), short-chain chlorinated paraffins(SCCPs) as well as aromatic and chlorinated polycyclic aromatic hydrocarbons(Cl-PAHs) were formed synergistically during the thermal decomposition of CP-52(a class of CP products).However, the transformation mechanisms of CP-52 to these compounds are still not very clear.This article presents a mechanistic analysis on the decomposition of CP-52 experimentally and theoretically. It was found that CP-52 initially undergoes dehydrochlorination and carbon chain cleavage and it transformed into chlorinated and unsaturated hydrocarbons. Cyclization and aromatization were the most accessible pathways at low temperatures(200–400°C), both of which produce mostly aromatic hydrocarbons. As the temperature exceeds 400°C, the hydrocarbons could decompose into small molecules, and the subsequent radical-induced reactions become the predominant pathways, leading to the formation of Cl-PAHs. The decomposition of CP-52 was investigated by using density functional theory and calculations demonstrating the feasibility and rationality of PCB and PCN formation from chlorobenzene. The results improve the understanding of the transformation processes from CP-52 to SCCPs and Cl-PAHs as well as provide data for reducing their emissions during thermal-related processes.展开更多
基金the Collaborative Project of the Chinese Academy of Sciences and Hebei Academy of Sciences supported by Hebei Academy of Sciences,China.(Grant No.191401).
文摘The potential threats of polycyclic aromatic hydrocarbons(PAHs)and chlorinated/brominated PAHs(Cl/Br-PAHs)to human health from particulate matter in the urban ambient air were studied using human health risk assessments.The risk to human health caused by exposure to PAHs was evaluated in Shijiazhuang,China,from January to December 2018.The PAHs concentration range was 16.02e475.21 ng/m3 and the toxic equivalent was 13.605 ng/m3.For adults,the average carcinogenic risk caused by respiratory exposure was 5.163×10^-6 and the resulting loss of life expectancy was 32.10 min.The human health risks of respiratory exposure to Cl/Br-PAHs in atmospheric samples from the Haidian District,Beijing,China,were evaluated from November 2017 to July 2018.The concentration ranges for the Cl-and Br-PAHs were 60.38e482.17 pg/m3 and 1.32e25.35 pg/m3,respectively.The average carcinogenic equivalent concentrations were 0.3274 pg/m3 and 0.0061 pg/m3 for the Cl-and Br-PAHs,respectively.For adults the average carcinogenic risks caused by respiratory exposure were 1.243×10^-10 and 2.316×10^-12 for the Cl-and Br-PAHs,respectively.The resulting loss of life expectancy values were 0.001 min(Cl-PAHs)and 0.00 min(Br-PAHs).The pollution concentrations and toxic equivalents of the Cl/Br-PAHs in Beijing and of the PAHs in Shijiazhuang both showed toxicity was high in the winter.The average carcinogenic risk for exposure of adults to PAHs in Shijiazhuang was low with certain potential hazards.The concentration of Cl-PAHs in Beijing was higher than that of Br-PAHs,and the average carcinogenic risk for exposure of adults to Cl/Br-PAHs was very low with slight harm.
基金supported by the National Natural Science Foundation of China(Nos.20877090,21077123,21377143)
文摘The brominated products, formed in chlorination treatment of benzophenone-4 in the presence of bromide ions, were identified, and the formation pathways were proposed.Under disinfection conditions, benzophenone-4 would undertake electrophilic substitution generating mono- or di-halogenated products, which would be oxidized to esters and further hydrolyzed to phenol derivatives. The generated catechol intermediate would be transformed into furan-like heterocyclic product. The product species were p H-dependent,while benzophenone-4 elimination was chlorine dose-dependent. When the chlorination treatment was performed on ambient water spiked with benzophenone-4 and bromide ions, most of brominated byproducts could be detected, and the acute toxicity significantly increased as well.
基金Project supported by the National Hi-Tech Research and Development Program (863) of China (No.2006AA06Z311)the National Natural Science Foundation of China (No.50808052)
文摘The formation of brominated trihalomethanes (THMs-Br) which is proved more carcinogenic than their chlorinated analogues reported was very different at various water qualities.This study was performed to assess the effects of water quality parameters (bromide concentration,pH value and ammonia concentration),chlorination conditions (chlorine dose,reaction time) and ratios of Br-/DOC and Br-/Cl2 consumption on the formation and distribution of THMs-Br in chlorination.The results showed good correlation between the bromine incorporation factor (BIF) n(Br) and Br-/Cl2 consumption ratio.The formation of total THM (TTHM) was found to decrease with increasing ammonia concentration but to increase with bromide concentration and pH value.The n(Br) trends were significantly affected by the presence of bromide concentration.The effects on the molar yields of THMs were more strongly influenced by bromide concentration and dissolved organic carbon (DOC) concentration than pH value and natural organic matter (NOM) source.High Br-/DOC and Br-/Cl2 favor the formation of THMs-Br over chlorinated THMs (THMs-Cl).The experimental data including the main parameters such as bromide,DOC,ammonia,pH and reaction time were used for developing the predictive model for THMs-Br.
文摘Brominated flame retardants(BFRs),have been extensively utilized in modern industry,contaminate aquatic ecosystems.They exhibit bioaccumulation and biomagnification properties,posing significant risks to human health,such as developmental disorders,endocrine disruption,and other adverse effects.Current treatment methods for BFRs encompass chemical,electrochemical,biological,and advanced oxidation processes(AOPs).Among them,AOPs are particularly notable for their stability,ease of control,and production of clean end-products.This paper focuses on employing a titanium dioxide(TiO_(2))photocatalytic system to investigate the degradation of 2,4,6-tribromophenol(TBP).
基金supported by the Fundamental Research Funds for the Central Universities(Nos.KYCYXT2023001,and XUEKEN2022034).
文摘Currently,ferrate(VI)oxidation technology(FOT)has been regarded as one of the most promising options for the degradation of emerging organic pollutants.However,the role and transformation of chloride ions(Cl^(−))in FOT have not been well explored.The current study aims to investigate the formation of chlorinated phenolic byproducts upon ferrate(VI)oxidation processes.The obtained results indicate that chlorides suffering ferrate(VI)attack will be transformed to active chlorine species(ACS),which will subsequently lead to the formation of highly toxic aromatic chlorinated byproducts.The identified byproducts include common chlorinated phenolic derivatives,as well as complex chlorinated oligomer byproducts with ether structures(mainly dimers and trimers).While the formation of common chlorophenols can be ascribed to the electrophilic substitution reactions mediated by ACS,the oligomer byproducts are generated via coupling reactions between chlorinated phenoxy radicals.ECOSAR software predicts that the generated chlorinated oligomer byproducts exhibit high ecotoxicological effects.As a whole,the above findings shed light on the potential risk of FOT in real practice.
文摘Objectives:Photodynamic therapy(PDT)is a minimally invasive method used in the treatment of various cancers and skin diseases,but it is not widely used in bone cancer,where the current therapy is often not effective and accompanied by side effects.Alternative and more effective therapies like PDT are needed.In this in-vitro study,the effect of the photosensitizer(PS)chlorin e6(Ce6)on cancerous bone tumor cells using PDT was examined.Methods:A total of 27 tissue specimens from patients with primary bone cancers or bone metastases of different origins were genetically characterized and treated with PDT.Following a 24-h incubation,cell viability was determined,and the effect of PDT on cell migration was analyzed over 48 h.Results:We could demonstrate that the effect on proliferation of PDT in combination with the PS Ce6 was best in cells isolated from primary osteosarcoma and in bone metastases from mammary carcinomas.Besides proliferation,PDT was also effective in inhibiting the migration of these cells.A statistically significant correlation between the PDT effect and CD164 gene expression was detected,indicating that a high expression of this gene could result in a higher effectiveness of the photodynamic treatment.Conclusion:This study analyzes for the first time the effect of PDT in bone cancers and metastases and shows the potential of treating these cancer types with Ce6 PDT.
文摘A method was developed for determination of chlorine and bromine in plant materials by ion chromatography using temperature programing-semi molten for sample preparation. Values of detection limits of the method found were 1.0×10^-5 for CI and 1.3×10^-6 for Br. The measuring range of the method found were 0.3-20.0 mg/L for CI and 4,0-120,0 μg/L for Br. The results obtained agreed quite well with those reference values.
文摘This review summarizes the environmental levels,toxicity effects and analytical development of Tris(2,3-dibromopropyl)Isocyanurate(TBC).Further study is required on the environmental behavior of TBC,mechanism of toxicity and alternative development.
基金supported by the National Natural Science Foundation of China (No. 41103054,40821003,41073081)the Earmarked Fund of the State Key Laboratory of Organic Geochemistry (No. OGL-200905)
文摘Accelerated industrialization and urbanization,and unregulated disposal of waste of electric and electronic equipment（e-waste） in China have caused environmental pollution of brominated flame retardants（BFRs）.This review summarized the levels,trends,and bioaccumulation characteristics of polybrominated diphenyl ethers（PBDEs） and other potential alternative BFRs including hexabromocyclododecanes（HBCDs）,1,2-bis（2,4,6-dibromophenoxy） ethane（BTBPE） and decabromodiphenylethane（DBDPE） in wildlife from China.PBDE levels in wildlife from China were generally higher than those from other parts in Asia,and were comparable to those from Europe but were lower than those from North America.However,wildlife from the e-waste recycling sites in South China and East China contained much higher PBDEs compared to other reports around the world,suggesting the heavy contamination of PBDEs in these regions.The alternative BFRs were also detected in wildlife,revealing that the animals are exposed to these chemicals,in addition to PBDEs.Temporal trends indicated by levels in marine mammals from South China suggested that PBDE levels increased from the beginning of 1990s to 2000s,but decreased from the middle of 2000s,followed by relatively steady levels.In contrast,HBCDs were found to be continuously increasing from 1997 to 2007,indicating the increasing usage of HBCDs in China in recent years.Compared to PBDE profiles found in other parts,aquatic species and birds from China contained relatively higher contributions of BDE28 and 209,respectively,suggesting the possible different usage pattern of PBDEs.Future works including keeping monitoring at a reasonable scale and frequency to make sure levels near urban centers indicative of population do not increase are needed.Additionally,focus effort on e-waste recycling regions to look for impacts and to determine if regulation/controls are resulting in lower environmental contamination,and incorporation of sentinel species in monitoring efforts are recommended.
基金supported by the Heilongjiang Province Postdoctoral Research Funding (No. AUGA41001074)
文摘This study reports the presence of brominated flame retardants in the topsoil in and around Harbin, a city in northeastern China. Samples of soil were collected from 17 locations in 2006, and the levels of 9 polybrominated diphenylethers （PBDEs 17, 28, 47, 66, 99, 100, 153, 154, and 183） ranged from 2.45 to 55.9 pg/g dry weight （dw） with a mean of 26.3 pg/g dw. These levels are very low comparing with those for some cities in Europe and USA. BDE 209 and hexabromocyclododecane were the two dominant congeners, with mean concentrations of 520 pg/g dw and 1750 pg/g dw, respectively. The concentrations of the total nine PBDE congeners clearly decreased from urban areas to background, but the compositions of individual congeners differed. Proportions of heavier congeners decreased while those of lighter congeners increased, along urban-rural-background transect, providing evidence for an urban fractionation effect. Correlation analysis indicated similar sources for PBDEs, hexabromocyclododecane, and 1,2-bis（2,4,6-tribromophenoxy）-ethane from urban areas but pentabromoethylbenzene was probably present due to long-range atmospheric transport. Principal component analysis was used to determine the characteristics of the relationships among these brominated flame retardants in the field.
基金supported by the National Basic Research(973)Program of China(No.2014CB441102)the National Natural Science Foundation of China(No.21177139)
文摘Brominated phenols （BPs）, a widely used group of emerging flame retardants, are important environmental contaminants and exhibit endocrine disrupting potential. Method for simultaneous determination of tetrabromobisphenol A （TBBPA）, tribromophenol （TBP）, dibromophenols （DBPs） and monobromophenols （MBPs） in soils using gas chromatography-mass spectrometry analysis （GC/MS） was successfully developed. Cleanup methods for soil extracts including several solid-phase extraction cartridges and different elution solvents were compared and optimized. Florisil cartridge with dichloromethane as the elution reagent was selected for sample cleanup owing to its high and reproducible recoveries of the target analytes in soils. Derivatization conditions were tested and the optimal conditions were obtained with 20 μL silylation reagent at room temperature. The chromatographic separation was optimized with different columns and DB-XLB column was selected for its excellent separation of the analytes. The limits of detection for the target compounds were from 0.04 to 0.19 ng/g. Mean recoveries of the compounds from spiked soils exceeded 84% with a good reproducibility, excepting that the recovery of 2-bromophenol was relatively poor （lower than 55%） due to its instability. The developed method was applied to the determination of the BPs in the soils collected from e-waste sites. The contents of BPs in the soils were at ng/g levels with TBBPA and TBP the most frequently detected. To our knowledge, this is the first report for the simultaneous determination of TBBPA, TBP, DBPs and MBPs in soils.
基金supported by the National Natural Science Foundation of China (No.21337002)the National Basic Research Program (973) of China (No.2015CB453100)
文摘Short-chain chlorinated paraffins(SCCPs) are produced in high volume and have the high potential to pose a threat to human health. However, little information is available for SCCP contamination in human blood/plasma/serum, mainly due to the difficulty of sample preparation and quantitative analysis. A method using high resolution gas chromatography coupled with electron capture negative ionization low resolution mass spectrometry(HRGC–ECNI/LRMS) was developed and validated to measure SCCPs in human plasma. The pretreatment process included protein denaturation and lipid elimination, liquid–liquid extraction with a mixture of n-hexane/dichloromethane(1:1, V/V), and cleanup on a multilayer silica column. The blank controls, including procedural blank, vacuum blood collection tube blank, and instrumental blank, were the most pivotal points for the reliable analysis of SCCPs. The average value of procedural blanks was 9.0 ng/g; and the method detection limit(MDL), calculated as the sum of the average procedural blank value and 3 times of the standard deviation of the procedural blanks, was 12.6 ng/g plasma. The validated method was applied to measure the concentrations of the total SCCPs(∑ SCCPs) in50 plasma samples from a general population. The measured plasma concentrations of ∑SCCPs ranged from <MDL to 203 ng/g wet weight(ww), with an average value of 32.0 ng/g ww.The relative abundance profiles of SCCPs in plasma samples were dominated by C10- and C11-CP congener groups centered on Cl6–7. The developed method can be used for the comprehensive and large-scale investigation of SCCP levels in human plasma.
基金support from the NSF(Grant No.99-929-01-26)national“863”program(Grant No.2001AA620403).
文摘A new brominated phenylpropylaldehyde and its dimethyl acetal together with a new natural brominated phenol were isolated from Rhodomela confervoides. Their structrues were elucidated as 2-methyl-3-(2,3-dibromo-4,5-dihydroxyphenyl)propylaldehyde, 2-methyl-3-(2,3-di-bromo-4,5-dihydroxyphenyl) propylaldehyde dimethyl acetal and 3-bromo-4,5-dihydroxybenzoic acid methyl ester by spectroscopic techniques including IR, HRFABMS, ID and 2DNMR experiments.
基金supported by National Natural Science Foundation of China(No30873153)the Key Projects of Shanghai in Biomedical(No08431902700)the Scientific Research Foundation of State Education Ministry for the Returned Overseas Chinese Scholars
文摘An efficient and mild protocol for bromination of aryl azides with N-bromosuccinimide（NBS） under FeCl_3 catalysis in 1,2- dichloroethane was developed.It is proved to be an efficient method for obtaining brominated aryl azides.
基金supported by the National Natural Science Foundation of China (No. 40821003)the Guangdong Natural Science Foundation (No. 7118013)the State Key Laboratory of Organic Geochemistry and the Hong Kong Polytechnic University Joint Student Program
文摘Air samples were collected simultaneously at platform,mezzanine and outdoor in five typical stations of subway system in Shanghai,China using stainless steel canisters and analyzed by gas chromatography-mass selective detector （GC-MSD） after cryogenic pre-concentration.Benzene,toluene,ethylbenzene and xylenes （BTEX） at the platforms and mezzanines inside the stations averaged （10.3±2.1）,（38.7±9.0）,（19.4±10.1） and （30.0±11.1） μg/m 3,respectively;while trichloroethylene （TrCE）,tetrachloroethylene （TeCE） and para-dichlorobenzene （pDCB）,vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of （3.6±1.3）,（1.3±0.5）,（4.1±1.1）,（2.2±1.1） and （1.2±0.3） μg/m 3,respectively.Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor （platforms and mezzanines） than outdoor with average indoor/outdoor （I/O） ratios of 1.1–9.5,whereas no significant indoor/outdoor differences were found except for benzene and TrCE.The highly significant mutual correlations （p0.01） for BTEX between indoor and outdoor and their significant correlation （p0.05） with methyl tert-butyl ether （MTBE）,a marker of traffic-related emission without other indoor and outdoor sources,indicated that BTEX were introduced into the subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source.TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air,especially in the mezzanines.
基金supported by the National Natu-ral Sciences Foundation of China (No. 50525824)the Tianjin Special Innovation Fund (No. 06FZZDSH00900,TJZX1-YW03)the National Water Project (No.2008ZX07314-003)
文摘The effects of ozonation on the formation potential of typical disinfection byproducts （DBPs） and the changes of genotoxicity during post chlorination of tertiary effluent from a sewage treatment plant were investigated. Ozonation enhanced the yields of all detected chlorine DBPs except CHCI3. At a chlorine dose of 5 mg/L, the three brominated THMs and five HAAs increased, while chloroform decreased with the increase of ozone dose from 0 to 10 mg/L （ozone dose in consumption base）. At a chlorine dose of 10 mg/L, the two mixed bromochloro species THMs and two dominant HAAs （DCAA and TCAA） increased firstly and then decreased with the increase of ozone dose, with the turning point approximately occurring at an ozone dose of 5 mg/L. The genotoxicity detected using umu test, on the other hand, was removed from 7 Ixg 4-NQO/L to a negligible level by ozonation under an ozone dose of 5 mg/L. Chlorination could further remove the genotoxicity to some extent. It was found that SUVA （UV absorbance divided by DOC concentration） might be used as an indicative parameter for monitoring the removal of genotoxicity during the oxidation.
基金Funded by the National Natural Science Foundation of China(No.21264006)National Scholarship Fund of China(No.201308460040)
文摘To elucidate the mechanism of brominated natural rubber(BNR), eight BNR samples with different bromine content were prepared from latex in different bromination time, and the microstructures were characterized by Fourier transform infrared spectroscopy(FTIR) and ~1H-NMR spectroscopy, respectively. The hardness of BNR increased and its nature transformed from elastomer to resin with the increase of bromine content. Unlike chlorinated natural rubber(CNR), FTIR showed that there were no carbonyl groups on the molecular chains of BNR. ~1H-NMR spectroscopy revealed that the reaction activity of bromine and the secondary hydrogen atom of BNR were much higher than those of the primary one. The brominated substitution took place in the hydrogen atom of CH_3 and CH_2 groups firstly, then in the late period of bromination the bond of C=C was transferred to the saturated bond of C-C due to the Markovnikov addition of hydrogen bromide. Based on these findings, the mechanism of BNR from latex could be deduced as a free radical reaction and the detailed bromination process was presented.
基金This work was financially supported by the National Natural Science Foundation of China(No.51673195).
文摘Poly（propylene carbonate） （PPC）, the copolymerization product of carbon dioxide and propylene oxide, was chlorinated for the first time in our laboratory. Nuclear magnetic resonance （NMR） spectroscopy and ion chromatography test showed that chlorine atoms were successfully introduced onto the polymer chains of PPC. We named this newborn polymer material as chlorinated poly（propylene carbonate） （CPPC）. It is worth noting that the reaction conditions of the chlorination of PPC were quite mild, which could be easily and simply realized at industrial level. What is more important is that CPPC possessed many more distinguished properties in solubility, wettability, adhesiveness, and gas barrier compared with PPC. For example, the bonding strength of CPPC as thermal adhesive is nearly four times higher than that of PPC for wood, stainless steel and glass. The oxygen permeability coefficient of CPPC exhibits a decrease of 33% compared with that of PPC. Moreover, CPPC is quite stable in air, whereas it could be well biodegraded in soil compared with PPC. These results indicated that CPPC could be widely used in the fields of coating, adhesive, barrier materials and so on, which could greatly promote the development of PPC industry.
基金financially supported by the National Natural Science Foundation of China (Nos.51811530096, 21875286)the National Key Research & Development Projects of China (No.2017YFA0206600)Science Fund for Distinguished Young Scholars of Hunan Province (No.2017JJ1029)
文摘Improving the performance and reducing the manufacturing costs are the main directions for the development of organic solar cells in the future.Here,the strategy that uses chemical structure modification to optimize the photoelectric properties is reported.A new narrow bandgap(1.30 eV)chlorinated non-fullerene electron acceptor(Y15),based on benzo[d][1,2,3] triazole with two 3-undecylthieno[2’,3’:4,5] thieno[3,2-b] pyrrole fused-7-heterocyclic ring,with absorption edge extending to the near-infrared(NIR) region,namely A-DA’D-A type structure,is designed and synthesized.Its electrochemical and optoelectronic properties are systematically investigated.Benefitting from its NIR light harvesting,the fabricated photovoltaic devices based on Y15 deliver a high power conversion efficiency(PCE) of 14.13%,when blending with a wide bandgap polymer donor PM6.Our results show that the A-DA’D-A type molecular design and application of near-infrared electron acceptors have the potential to further improve the PCE of polymer solar cells(PSCs).
基金supported by the National Natural Science Foundation of China (Nos.21625702,21337002,21621064)the National Basic Research Program of China (No.2015CB453102)the Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDB14010400)
文摘The increasing production and usage of chlorinated paraffins(CPs) correspondently increase the amount of CPs that experience thermal processes. Our previous study revealed that a significant amount of medium-chain chlorinated paraffins(MCCPs), short-chain chlorinated paraffins(SCCPs) as well as aromatic and chlorinated polycyclic aromatic hydrocarbons(Cl-PAHs) were formed synergistically during the thermal decomposition of CP-52(a class of CP products).However, the transformation mechanisms of CP-52 to these compounds are still not very clear.This article presents a mechanistic analysis on the decomposition of CP-52 experimentally and theoretically. It was found that CP-52 initially undergoes dehydrochlorination and carbon chain cleavage and it transformed into chlorinated and unsaturated hydrocarbons. Cyclization and aromatization were the most accessible pathways at low temperatures(200–400°C), both of which produce mostly aromatic hydrocarbons. As the temperature exceeds 400°C, the hydrocarbons could decompose into small molecules, and the subsequent radical-induced reactions become the predominant pathways, leading to the formation of Cl-PAHs. The decomposition of CP-52 was investigated by using density functional theory and calculations demonstrating the feasibility and rationality of PCB and PCN formation from chlorobenzene. The results improve the understanding of the transformation processes from CP-52 to SCCPs and Cl-PAHs as well as provide data for reducing their emissions during thermal-related processes.
