Zunyao Wang

Nanjing University, Nan-ching, Jiangsu Sheng, China

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Publications (80)224.65 Total impact

  • Xiaolan Zeng · Xiaoling Zhang · Zunyao Wang ·
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    ABSTRACT: Density functional theory (DFT) calculations at the B3LYP/6-311++G(2df,p) level of theory have been carried out to investigate the atmospheric oxidation mechanisms of some polyfluorinated dibenzo-p-dioxins (PFDDs), initiated by OH radical. The computed results show that all OH addition reactions of PFDDs are thermodynamically spontaneous processes and the branch ratio of the PFDD-OH adducts is determined by the magnitude of the Gibbs free energies of activation (ΔrG(≠)) and hence rate constants (k) for addition reactions. The OH reactions with all studied PFDDs are dominated by Cγ-addition and the total rate constants for OH addition decrease with increasing the number of fluorine atom substituting at α positions. Under the atmospheric conditions, the subsequent O2 addition reactions of PFDD-OH adducts occur hardly thermodynamically and are slow kinetically. For PFDD-α(β)-OH adducts without F atom at same positions the main reaction pathway is H abstraction by O2, while PFDD-γ-OH adducts will undergo fused-ring C-O bond cleavage, affording the substituted phenoxy radicals.
    Chemosphere 02/2016; 144:2036-2043. DOI:10.1016/j.chemosphere.2015.10.106 · 3.34 Impact Factor
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    ABSTRACT: As one of the first generation of fluoroquinolone antibiotics, flumequine (FLU) has been detected ubiquitously in surface waters and municipal wastewaters. In light of FLU's possible adverse effects on aquatic species, the removal of this antibiotic has received worldwide attention. In this study, the kinetics, transformation products, mechanisms and toxicity variations of the ozonation process for FLU were systematically determined. The possible effects of solution pH, addition of inorganic ions, dissolved organic matter, and tert-butyl-alcohol (a radical scavenger), as well as the type of water matrices on FLU removal by ozonation, were studied from the perspective of the degradation kinetics. The data obtained suggested that ozone can be used as an effective oxidant for the fast removal of FLU from natural waters. Using liquid chromatography-mass spectrometry, a total of thirteen transformation products of FLU during ozonation were identified, and their specific reaction mechanisms were also proposed. The degradation pathways involving the hydroxylation, decarboxylation and defluorination were tentatively proposed. Meanwhile, the generation of three low-molecular-weight carboxylic acids was also observed. In addition, the potential toxicity of the transformation mixtures of FLU by ozone was evaluated. Overall, this paper can be a unique contribution to the systematic elucidation of the ozonation process of this antibiotic in water.
    Science of The Total Environment 01/2016; 541:167-175. DOI:10.1016/j.scitotenv.2015.09.048 · 4.10 Impact Factor
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    Mingbao Feng · Hao Jin · Ruijuan Qu · Bingzhe Xu · Zunyao Wang ·
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    ABSTRACT: In this study, five different congeners of polyfluorinated dibenzo-P-dioxins (PFDDs) (1,8-di-FDD, 1,3,8-tri-FDD, 1,3,6,8-tetra-FDD, 2,3,7,8-tetra-FDD and 1,2,3,4,5,6,7,8-octa-FDD), representing different numbers and positions of fluorine substituents of all 75 PFDD congeners, were synthesized and purified to evaluate their potential environmental impact on living organisms. Their toxicity was evaluated by determining the impact on the organo-somatic indices (OSI) and ethoxyresorufin-O-deethylase (EROD) activity in mice (Mus musculus) after intragastric administration with different doses (0.5-100 μg/kg body weight) for 3 days. The results showed that these PFDDs significantly inhibited the growth and changed the OSI in mouse tissues. Notably, hepatic EROD activity was markedly induced in mice after exposure to these PFDDs, probably indicating a high affinity of binding to the aryl hydrocarbon receptor. Overall, these findings provided some preliminary but alarming toxicity data of PFDDs, and filled information gaps in the toxicological databases for living organisms.
    Journal of Environmental Science and Health Part A 11/2015; DOI:10.1080/10934529.2015.1087742 · 1.16 Impact Factor
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    ABSTRACT: In recent years, flumequine (FLU) has been ubiquitously detected in surface waters and municipal wastewaters. In light of its potential negative impacts to aquatic species, growing concern has been arisen for the removal of this antibiotic from natural waters. In this study, the kinetics, degradation mechanisms and pathways of aqueous FLU by persulfate (PS) oxidation were systematically determined. Three common activation methods, including heat, Fe(2+) and Cu(2+), and a novel heterogeneous catalyst, namely, polyhydroquinone-coated magnetite/multi-walled carbon nanotubes (Fe3O4/MWCNTs/PHQ), were investigated to activate PS for FLU removal. It was found that these three common activators enhanced FLU degradation obviously, while several influencing factors, such as solution pH, inorganic ions (especially HCO3(-) at 5 mmol/L) and dissolved organic matter extracts, exerted their different effects on FLU removal. The catalysts were characterized, and an efficient catalytic degradation performance, high stability and excellent reusability were observed. The measured total organic carbon levels suggested that FLU can be effectively mineralized by using the catalysts. Radical mechanism was studied by combination of the quenching tests and electron paramagnetic resonance analysis. It was assumed that sulfate radicals predominated in the activation of PS with Fe3O4/MWCNTs/PHQ for FLU removal, while hydroxyl radicals also contributed to the catalytic oxidation process. In addition, a total of fifteen reaction intermediates of FLU were identified, from which two possible pathways were proposed involving hydroxylation, decarbonylation and ring opening. Overall, this study represented a systematical evaluation regarding the transformation process of FLU by PS, and showed that the heterogeneous catalysts can efficiently activate PS for FLU removal from the water environment. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Water Research 11/2015; 85:1-10. DOI:10.1016/j.watres.2015.08.011 · 5.53 Impact Factor
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    ABSTRACT: Experiments were conducted to investigate the effect of four different carbon nanotubes single- and multi-walled carbon nanotubes (SWCNTs and MWCNTs) and hydroxylated and carboxylated multi-walled carbon nanotubes (OH-MWCNTs and COOH-MWCNTs) on Cd toxicity to the aquatic organism Daphnia magna. The acute toxicity results indicated that all CNTs could enhance the toxicity of Cd to D. magna. Furthermore, the filtrate toxicity and adsorption tests showed that the toxicity-increasing effect of SWCNTs and MWCNTs in the overall system was mainly caused by catalysts impurities from the pristine CNTs, whereas the greater adsorption of Cd onto OH-MWCNTs (30.52 mg/g) and COOH-MWCNTs (24.93 mg/g) was the key factor contributing to the enhanced toxicity. This result raised a concern that the metal catalyst impurities, adsorption capacities, and accumulation of waterborne CNTs were responsible for the toxicity of Cd to aquatic organism.
    Environmental Pollution 11/2015; DOI:10.1016/j.envpol.2015.10.053 · 4.14 Impact Factor
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    Mingbao Feng · Qun He · Jiaqi Shi · Li Qin · Xuesheng Zhang · Ping Sun · Zunyao Wang ·
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    ABSTRACT: In the present study, the toxic effect of decabromodiphenyl ether (BDE-209), an important brominated fire retardant, on soil was evaluated by amending with different concentrations (0, 1, 10 and 500 mg/kg dry weight) for 40 d. The activities of three soil enzymes (urease, catalase and alkaline phosphatase) were measured as the principal assessment endpoints. Meanwhile, the effects of natural environmental factors, such as light conditions and soil biota, on BDE-209 intoxication were studied. For the latter, 30 earthworms (Metaphire guillelmi) with fully-matured clitella or ryegrass (Lolium perenne) with fully-matured leaves were exposed in soil amended with BDE-209. The activities of soil enzymes were adversely affected by BDE-209, especially for high-concentration treatments, with greater adverse effects in the dark than in the light. The presence of earthworms reduced toxicity to BDE-209, whereas ryegrass did not. The calculated integrated biomarker response index, which provides a general indicator of the "health status" of test species by combining different biomarker signals, further validated these findings. Moreover, the antioxidant status (oxidant-antioxidant balance) of these two biota was assessed. Results of this assessment indicated that BDE-209 significantly affected the activities of antioxidant enzymes (superoxide dismutase and catalase) and enhanced the levels of malondialdehyde in both species. The present study may facilitate a better understanding of the toxicity of BDE-209 toward the real soil environment. This article is protected by copyright. All rights reserved.
    Environmental Toxicology and Chemistry 10/2015; DOI:10.1002/etc.3272 · 3.23 Impact Factor
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    ABSTRACT: Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retar-dants and has attracted more and more attention. In this work, the parent TBBPA with an initial concentration of 100 mg/L was completely removed after 6 min of ozonation at pH 8.0, and alkaline conditions favored a more rapid removal than acidic and neutral conditions. The presence of typical anions and humic acid did not significantly affect the degradation of TBBPA. The quenching test using isopropanol indicated that direct ozone oxidation played a dominant role during this process. Seventeen reaction intermediates and products were identified using an electrospray time-of-flight mass spectrometer. Notably, the generation of 2,4,6-tribromophenol was first observed in the degradation process of TBBPA. The evolution of reaction products showed that ozonation is an efficient treatment for removal of both TBBPA and intermediates. Sequential transformation of organic bromine to bromide and bromate was confirmed by ion chromatography analysis. Two primary reaction pathways that involve cleavage of central carbon atom and benzene ring cleavage concomitant with debromination were thus proposed and further justified by calculations of frontier electron densities. Furthermore, the total organic carbon data suggested a low mineralization rate, even after the complete removal of TBBPA. Meanwhile, the acute aqueous toxicity of reaction solutions to Photobacterium Phosphoreum and Daphnia magna was rapidly decreased during ozonation. In addition, no obvious difference in the attenuation of TBBPA was found by ozone oxidation using different water matrices, and the effectiveness in natural waters further demonstrates that ozonation can be adopted as a promising technique to treat TBBPA-contaminated waters.
    PLoS ONE 10/2015; 10(10):1-17. DOI:10.1371/journal.pone.0139580 · 3.23 Impact Factor
  • Jianbiao Peng · Jianhua Li · Huanhuan Shi · Zunyao Wang · Shixiang Gao ·
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    ABSTRACT: As widely used chemicals intended to protect human being from infection of microorganisms, disinfectants are ubiquitous in the environment. Among them chlorine-substituted phenol is a basic structure in many disinfectant molecules. Removal of these pollutants from wastewater is of great concern. The oxidative degradation of antimicrobial agents such as triclosan, chlorofene, and dichlorofene by a Fenton-like system Cu(2+)/H2O2 was examined. Reaction conditions such as temperature, initial concentrations of H2O2 and Cu(2+), and pH were optimized using triclosan as a representative. The degradation kinetics of the above disinfectants followed pseudo-first-order kinetics under the investigated conditions. Fourteen chlorophenols (CPs) with different chlorine substitution were also studied to evaluate the influence of molecular structure on the degradation process in the Cu(2+)/H2O2 system. Fourteen structure-related parameters were calculated using Gaussian 09 program. A quantitative structure-activity relationship (QSAR) model was established using SPSS software with measured rate constant (k) as dependent variable and calculated molecular descriptors as independent variables. A three-parameter model including energy of HOMO (E homo), molar heat capacity at constant volume (C v (θ)), and the most positive net charge of hydrogen atoms (qH(+)) was selected for k prediction, with correlation coefficient R (2) = 0.878. Analyses of the model demonstrated that the C v (θ) was the most significant factor affecting the k of chlorophenols. Variance analysis and standard t-value test were used to validate the model.
    Environmental Science and Pollution Research 09/2015; DOI:10.1007/s11356-015-5454-y · 2.83 Impact Factor
  • Jiaoqin Liu · Ruijuan Qu · Liqing Yan · Liansheng Wang · Zunyao Wang ·
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    ABSTRACT: Perfluorooctane sulfonate (PFOS) and zinc have been detected in aquatic environment widely. In order to study the combined effects of PFOS and Zn, a series of experiments was conducted to explore the acute mortality, bioaccumulation and antioxidant status of Limnodrilus hoffmeisteri. The acute toxicity was evaluated by calculating 24h-EC50 values, and it was observed that 24h-EC50 values in single and joint treatments decreased with decreasing pH value or increasing exposure concentration. Toxic unit analysis suggested that the combined effects of the PFOS+Zn binary mixture were mostly simple addition, with 8 groups showing synergism and only one group showing antagonism. The analysis of internal Zn and PFOS concentration showed that the possible interaction between Zn and PFOS can affect the bioaccumulation of the two chemicals in L. hoffmeisteri. In addition, oxidative stress status was assessed by measuring oxidation-related biochemical parameters such as superoxide dismutase, glutathione peroxidase and malondialdehyde, and the integrated biomarker response index was estimated to rank the toxicity order. Exposures to Zn and PFOS were found to evoke some changes in the antioxidant defense system, and a strong self-adaptive ability was noticed for L. hoffmeisteri after 10 d exposure.
    Journal of hazardous materials 09/2015; 301:342-349. DOI:10.1016/j.jhazmat.2015.09.010 · 4.53 Impact Factor
  • Qun He · Ruijuan Qu · Xinghao Wang · Zhongbo Wei · Ping Sun · Zunyao Wang ·

    CLEAN - Soil Air Water 08/2015; DOI:10.1002/clen.201400124 · 1.95 Impact Factor
  • Xiaolan Zeng · Xuesheng Zhang · Li Qin · Zunyao Wang ·
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    ABSTRACT: The tissue distribution, excretion, and metabolic pathway of 2,2',4,4',5-penta-chlorinated diphenylsulfide (CDPS-99) in ICR mice were investigated after oral perfusion at 10mg/kg body weight (b.w.). Biological samples were extracted and separated and, for the first time, were determined by a novel, sensitive, and specific GC-MS method under the full scan and selected ion monitoring (SIM) modes. The results showed that the concentrations of CDPS-99 in the liver, kidneys, and serum reached a maximum after a one-day exposure and that the CDPS-99 concentration in the liver was the highest (3.43μg/g). The increase in the concentration of CDPS-99 in muscle, skin, and adipose tissue was slower, and the concentrations of CDPS-99 achieved their highest levels after 3 days of exposure. It was observed that the CDPS-99 concentration in adipose tissue was still very high (0.71μg/g) after 21 days of exposure, which suggested that CDPS-99 was able to accumulate in adipose tissue. In addition, mouse feces accounted for approximately 75% of the total gavage dose, indicating that CDPS-99 was mainly excreted via mouse feces. Metabolism analysis demonstrated that there were three possible metabolic pathways of CDPS-99 in mice: dechlorination reactions with the formation of tetra-CDPS and hydroxylation and oxidation reactions with the formation of OH-CDPS-99 and chlorinated diphenylsulfone. The present study will help to develop a better understanding of mammalian metabolism of CDPS-99. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 07/2015; 1001:90-97. DOI:10.1016/j.jchromb.2015.07.038 · 2.73 Impact Factor
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    Junhe Lu · Juan Shao · Hui Liu · Zunyao Wang · Qingguo Huang ·
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    ABSTRACT: Laccases are a type of extracellular enzymes produced by fungi, bacteria, and plants. Laccase can catalyze one-electron oxidation of a variety of phenolic compounds using molecular oxygen as the electron acceptor. In this study, transformation of halophenols (XPs) in laccase-catalyzed oxidation processes was explored. We first examined the intrinsic reaction kinetics and found that the transformation of XPs appeared first order to the concentrations of both XPs and laccase. A numerical model was developed to describe the role of humic acid (HA) in this process. It was demonstrated that HA could reverse the oxidation of XPs by acting as the inner filtrator of XP radical intermediates formed upon reactions between the substrates and laccase. The extent of such reversion was proportional to HA concentration. MS analysis in combination with quantum chemistry computation suggested that coupling products were generated. XPs coupled to each via C-C or C-O-C pathways, generating hydroxyl polyhalogenated biphenyl ethers (OH-PCDEs) and hydroxyl polyhalogenated biphenyls, respectively. Many of these polyhalogenated products are known to be hazardous to the ecosystem and human health but their genesis are not fully understood. This study shed light on their occurrence in the environmental media.
    Environmental Science and Technology 07/2015; 49(14). DOI:10.1021/acs.est.5b02399 · 5.33 Impact Factor
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    ABSTRACT: Nafion 117 membrane (N117), an important polymer electrolyte membrane (PEM), has been widely used for numerous chemical technologies. Despite its increasing production and use, the toxicity data for N117 and its combustion products remain lacking. Toxicity studies are necessary to avoid problems related to waste disposal in landfills and incineration that may arise. In this study, we investigated the histopathological alterations, oxidative stress bio-marker responses, and transcriptome profiles in the liver of male mice exposed to N117 and its combustion products for 24 days. An ion-chromatography system and liquid chromatography system coupled to a hybrid quadrupole time-of-flight mass spectrometry were used to analyze the chemical compositions of these combustion products. The transcriptomics analysis identified several significantly altered molecular pathways, including the metabolism of xeno-biotics, carbohydrates and lipids; signal transduction; cellular processes; immune system; and signaling molecules and interaction. These studies provide preliminary data for the potential toxicity of N117 and its combustion products on living organisms and may fill the information gaps in the toxicity databases for the currently used PEMs.
    PLoS ONE 06/2015; 10(6):1-18. DOI:10.1371/journal.pone.0128591 · 3.23 Impact Factor
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    ABSTRACT: This study examined the decomposition of perfluorooctanoic acid (PFOA) in enzyme catalyzed oxidative humification reactions (ECOHRs). ECOHRs are a class of reactions that are ubiquitous in the environment. Approximately 50% of PFOA in a mineral buffer solution was decomposed with the addition of laccase and 1-hydroxybenzotriazole after 157 days with a pseudo-first order rate constant of 0.0044/day (r2=0.89). No shorter-carbon chain perfluorocarobxylic acids were detected as degradation products during the experiment. However, partially fluorinated shorter-chain alcohols and aldehydes were identified by high-resolution mass spectrometry. These partially fluorinated compounds were likely products resulting from PFOA degradation via a combination of free radical decarboxylation, rearrangement and coupling processes. Fluoride was detected in the reaction solution, and the concentration indicated a 28.2% defluorination ratio during the treatment. This finding suggests that PFOA may be transformed during humification, and ECOHRs can potentially be used for the remediation of PFOA.
    06/2015; 2(7):198-203. DOI:10.1021/acs.estlett.5b00119
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    ABSTRACT: The thermal decomposition of Nafion N117 membrane, a typical perfluorosulfonic acid membrane that is widely used in various chemical technologies, was investigated in this study. Structural identification of thermolysis products in water and methanol was performed using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS). The fluoride release was studied using an ion-chromatography system, and the membrane thermal stability was characterized by thermogravimetric analysis. Notably, several types of perfluorinated compounds (PFCs) including perfluorocarboxylic acids were detected and identified. Based on these data, a thermolysis mechanism was proposed involving cleavage of both the polymer backbone and its side chains by attack of radical species. This is the first systematic report on the thermolysis products of Nafion by simulating its high-temperature operation and disposal process via incineration. The results of this study indicate that Nafion is a potential environmental source of PFCs, which have attracted growing interest and concern in recent years. Additionally, this study provides an analytical justification of the LC/ESI-MS/MS method for characterizing the degradation products of polymer electrolyte membranes. These identifications can substantially facilitate an understanding of their decomposition mechanisms and offer insight into the proper utilization and effective management on these membranes.
    Scientific Reports 05/2015; 5(9859):1-8. DOI:10.1038/srep09859 · 5.58 Impact Factor
  • Qun He · Xinghao Wang · Ping Sun · Zunyao Wang · Liansheng Wang ·
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    ABSTRACT: Tetrabromobisphenol A (TBBPA) is a well-known brominated flame retardant. It has been detected in the environment and shows high acute toxicity to different organisms at high concentrations. In this work, the effects of pH and dimethyl sulfoxide (DMSO) on the acute toxicity of TBBPA to Daphnia magna and Limnodrilus hoffmeisteri were tested, and the oxidative stress induced by TBBPA in livers of Carassius auratus was assessed using four biomarkers. The integrated biomarker response (IBR) was applied to assess the overall antioxidant status in fish livers. Moreover, fish tissues (gills and livers) were also studied histologically. The results showed that low pH and DMSO enhanced the toxicity of TBBPA. Furthermore, changes in the activity of antioxidant enzymes and glutathione level suggested that TBBPA generates oxidative stress in fish livers. The IBR index revealed that fish exposed to 3mg/L TBBPA experienced more serious oxidative stress than exposed to acidic or alkaline conditions. The histopathological analysis revealed lesions caused by TBBPA. This study provides valuable toxicological information of TBBPA and will facilitate a deeper understanding on its potential toxicity in realistic aquatic environments. Copyright © 2015 Elsevier B.V. All rights reserved.
    Aquatic toxicology (Amsterdam, Netherlands) 05/2015; 164. DOI:10.1016/j.aquatox.2015.05.005 · 3.45 Impact Factor
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    Hui Liu · Ping Sun · Hongxia Liu · Shaogui Yang · Liansheng Wang · Zunyao Wang ·
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    ABSTRACT: The hazardous potential of benzophenone (BP)-type UV filters is becoming an issue of great concern due to the wide application of these compounds in many personal care products. In the present study, the toxicities of BPs to Photobacterium phosphoreum and Daphnia magna were determined. Next, density functional theory (DFT) and comparative molecular field analysis (CoMFA) descriptors were used to obtain more detailed insight into the structure - activity relationships and to preliminarily discuss the toxicity mechanism. Additionally, the sensitivities of the two organisms to BPs and the interspecies toxicity relationship were compared. Moreover, an approach for providing a global index of the environmental risk of BPs to aquatic organisms is proposed. The results demonstrated that the mechanism underlying the toxicity of BPs to P. phosphoreum is primarily related to their electronic properties, and the mechanism of toxicity to D. magna is hydrophobicity. Additionally, D. magna was more sensitive than P. phosphoreum to most of the BPs, with the exceptions of the polyhydric BPs. Moreover, comparisons with published data revealed a high interspecies correlation coefficient among the experimental toxicity values for D. magna and Dugesia japonica. Furthermore, hydrophobicity was also found to be the most important descriptor of integrated toxicity. This investigation will provide insight into the toxicity mechanisms and useful information for assessing the potential ecological risk of BP-type UV filters. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Chemosphere 05/2015; 135:182-188. DOI:10.1016/j.chemosphere.2015.04.036 · 3.34 Impact Factor
  • Qun He · Li Qin · Xuesheng Zhang · Liansheng Wang · Ping Sun · Zunyao Wang ·
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    ABSTRACT: Sediment and water samples collected from 8 sites of the Yangtze River in Nanjing section were characterized with 31 congeners of polychlorodibenzothiophenes (PCDTs). Concentrations and percentage compositions of these PCDTs in water and sediments were analyzed by gas chromatography-mass spectrometry. Results showed that ∑PCDT concentrations in sediments were higher (0.86-1.75 μg/kg) than those in water (0.56-1.30 μg/L). A linear relationship existed between ∑PCDT concentrations and total organic carbon content in sediments, whereas there was a poor linearity between ∑PCDTs concentrations and dissolved organic carbon content in water phase. Moreover, percentage compositions showed that penta-chlorinated DTs were the predominant congeners both in sediments and water. Differences existed in the percentage compositions between water and sediments. Highly chlorinated DTs accounted for a larger proportion in sediments than those in water. In conclusion, the present study showed the prevalent contamination by PCDTs in sediments and water from the Nanjing section of the Yangtze River.
    Archives of Environmental Contamination and Toxicology 05/2015; 69(4). DOI:10.1007/s00244-015-0159-2 · 1.90 Impact Factor
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    Zhongkun Du · Guowei Wang · Shixiang Gao · Zunyao Wang ·
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    ABSTRACT: As a result of the ban on some brominated flame retardants (BFRs), the use of organophosphate flame retardants (OPFRs) increases, and they are detected in multi-environment media at higher frequency and concentrations. However, the toxicity data of OPFRs, especially those on developmental toxicology are quite limited, which prevents an accurate evaluation of their environmental and health risk. Because a previous study reported that two aryl-OPFRs induced cardiotoxicity during zebrafish embryogenesis, we designed experiments to compare the heart developmental toxicity of a series of aryl-OPFRs with alkyl-OPFRs and explored possible internal mechanism. First, acute toxicity of 9 frequently used OPFRs were studied with zebrafish embryos (2–96 hpf). By comparing the LC50 and EC50 (pericardium edema) data, two aryl-OPFRs, triphenyl phosphate (TPhP) and cresyl diphenyl phosphate (CDP) showed greater heart developmental toxicity than the others. It was also found that the acute toxicity of OPFRs varied mainly depending on their hydrophobicity. Further study on the cardiotoxicty of TPhP and CDP showed that the cardiac looping progress can be impeded by 0.10 mg/L TPhP or CDP exposure. Bradycardia and reduction of myocardium were also observed in 0.50 and 1.0 mg/L TPhP groups and 0.10, 0.50, and 1.0 mg/L CDP groups. 0–48 hpf is the vulnerable window of zebrafish cardiogenesis that can be easily affected by TPhP and CDP. RT-qPCR measurement on the expressions of key transcriptional regulators in cardiogenesis showed that BMP4, NKX2–5, and TBX5 were significantly inhibited at the exposure points of 12 hpf and 24 hpf which may be the internal factors related to the heart developmental toxicity. As zebrafish is a good model organism for human health study, the present results call for a greater attention to the health risk of fetus in pregnant women exposed to such OPFRs.
    Aquatic Toxicology 04/2015; 161. DOI:10.1016/j.aquatox.2015.01.027 · 3.45 Impact Factor
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    Mingbao Feng · Qun He · Lingjun Meng · Xiaoling Zhang · Ping Sun · Zunyao Wang ·
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    ABSTRACT: Perfluorooctane sulfonate, perfluorooctanoic acid, and copper have been recently regarded as ubiquitous environmental contaminants in aquatic ecosystems worldwide. However, data on their possible combined toxic effects on aquatic organisms are still lacking. In this study, a systematic experimental approach was used to assess the impacts of these chemicals and their mixtures on hepatic antioxidant status of Carassius auratus after 4 days. Oxidative stress was apparently observed for joint exposure by determining biochemical parameters (superoxide dismutase, catalase, glutathione peroxidase, reduced glutathione, and malondialdehyde). The integrated biomarker response index was calculated to rank the toxicity order, from which the synergistic effect was tentatively proposed for joint-toxicity action. In addition, these treatments significantly altered trace element homeostasis in different fish tissues, and the concentration distribution of these test chemicals was also measured. Taken together, these results provided some valuable toxicological data on the joint effects of perfluorinated compounds and heavy metals on aquatic species, which can facilitate further understanding on the potential risks of other coexisting pollutants in the natural aquatic environment. Copyright © 2015 Elsevier B.V. All rights reserved.
    Aquatic Toxicology 04/2015; 161. DOI:10.1016/j.aquatox.2015.01.025 · 3.45 Impact Factor

Publication Stats

344 Citations
224.65 Total Impact Points


  • 2004-2015
    • Nanjing University
      • • State Key Laboratory of Pollution Control and Resource Reuse
      • • School of Environment
      Nan-ching, Jiangsu Sheng, China
  • 2005-2009
    • Jiaxing University
      Kashing, Zhejiang Sheng, China
    • Yancheng Institute of Technology
      Yen-ch’eng-chen, Jiangsu Sheng, China