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Effect of ultraviolet irradiation and chlorination on ampicillin-resistant Escherichia coli and its ampicillin resistance gene

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Frontiers of environmental Science & Engineering 2016年第3期10卷 522-530页

作者： Yuchen PANG Jingjing HUANG Jinying XI Hongying HU Yun ZHU Environmental Simulation and Pollution Control State Key Joint Laboratory School of Environment Tsinghua University Beijing 100084 China State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC) Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China China Power Engineering Consulting Group Corporation Beijing 100120 China Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China School of Life Sciences Tsinghua University Beijing 100084 China

Antibiotic resistance is a serious public health risk that may spread via potable and reclaimed water. Effective disinfection is important for inactivation of antibiotic-resistant bacteria and disruption of antibiotic resistance genes. Ampicillin is a widely prescribed antibiotic but its effectiveness is increasingly undermined by resistance. In this study, changes in ampicillin resistance for Escherichia coli （E. coli） CGMCC 1.1595 were analyzed after exposure to different doses of ultraviolet （UV） or chlorine, and damage incurred by the plasmid encoding ampicillin resistance gene blaTEM-1 was assessed. We reported a greater stability in ampicillinresistant E. coli CGMCC 1.1595 after UV irradiation or chlorination when compared with previously published data for other E. coli strains. UV irradiation and chlorination led to a shift in the mortality frequency distributions of ampicillin-resistant E. coli when subse-quently exposed to ampicillin. The ampicillin hemiinhibitory concentration （IC5o） without disinfection was 3800mg·L^-1, and an increment was observed after UV irradiation or chlorination. The IC50 of ampicillin-resistant E. coli was 1.5-fold higher at a UV dose of 40 mJ·cm^-2, and was 1.4-fold higher when exposed to 2.0 mg·L^-1 chlorine. These results indicate that UV irradiation and chlorination can potentially increase the risk of selection for E. coli strains with high ampicillin resistance. There was no evident damage to blaTEM-1 after 1-10 mg Cl2· L^-1 chlorination, while a UV dose of 80 mJ·cm^-2 yielded a damage ratio for blaTEM-1 of approximately ***, high UV doses are required for effective disruption of antibiotic resistance genes in bacteria.

关键词： antibiotic resistance Escherichia coli ampicillin resistance gene ultraviolet irradiation chlorination

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Effect of gamma-ray irradiation at low doses on the performance of PES ultrafiltration membrane

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Radiation Physics and Chemistry 2016年 127卷 127-132页

作者： Zhang, Xue Niu, Lixia Li, Fuzhi Yu, Suping Zhao, Xuan Hu, Hongying Collaborative Innovation Center for Advanced Nuclear Energy Technology Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC) Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China Environmental Simulation and Pollution Control State Key Joint Laboratory School of Environment Tsinghua University Beijing 100084 China

The influence of gamma irradiation on the performance of polyether sulfone (PES) ultrafiltration (UF) membrane was investigated at low absorbed doses (0-75 kGy) using a cobalt source. The performance of the UF membranes was tested using low level radioactive wastewater (LLRW) containing three types of surfactants (anionic, cationic and nonionic surfactants). The physical and chemical properties of membrane surface were analyzed, and relationships between these properties and separation performance and fouling characteristics were determined. At 10-75 kGy irradiation, there were no significant changes observed in the membrane surface roughness or polymer functional groups, however the contact angle decreased sharply from 92° to ca. 70° at irradiation levels as low as 10 kGy. When membranes were exposed to the surfactant-containing LLRW, the flux decreased more sharply for higher dosed irradiated membranes, while flux in virgin membranes increased during the filtration processes. The study highlights that fouling properties of membrane may be changed due to the changes of surface hydrophilicity at low dose irradiation, while other surface properties and retentions remain stable. Therefore, a membrane fouling test with real or simulated wastewater is recommended to fully evaluate the membrane irradiation resistance. © 2016 Elsevier Ltd.

关键词： Gamma irradiation Membrane fouling PES membrane

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Impact of disinfection on drinking water biofilm bacterial community

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Journal of environmental Sciences 2015年第11期27卷 200-205页

作者： Zilong Mi Yu Dai Shuguang Xie Chao Chen Xiaojian Zhang State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC) Tsinghua University School of Environment Tsinghua University State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University

Disinfectants are commonly applied to control the growth of microorganisms in drinking water distribution systems. However, the effect of disinfection on drinking water microbial community remains poorly understood. The present study investigated the impacts of different disinfectants（chlorine and chloramine） and dosages on biofilm bacterial community in bench-scale pipe section reactors. Illumina MiS eq sequencing illustrated that disinfection strategy could affect both bacterial diversity and community structure of drinking water biofilm. Proteobacteria tended to predominate in chloraminated drinking water biofilms, while Firmicutes in chlorinated and unchlorinated biofilms. The major proteobacterial groups were influenced by both disinfectant type and dosage. In addition, chloramination had a more profound impact on bacterial community than chlorination.

关键词： Drinking water distribution systems Disinfection Microbial community High-throughput sequencing Firmicutes Proteobacteria

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基于GIS的中国深圳市城市快速路环境敏感性评估

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Engineering 2018年第2期 144-153页

作者：李骐安郭凤清关云涛 State Environmental Protection Key Laboratory of Microorganism Application and Risk Control School of Environment Tsinghua University Guangdong Provincial Engineering Technology Research Center for Urban Water Cycle and Water Environment Safety Graduate School at Shenzhen Tsinghua University College of Water Conservancy Engineering Tianjin Agricultural University

随着城市化、人口增长以及社会经济的迅猛发展,中国的城市生态环境日趋恶化。深圳市正在建设一条经过环境敏感区(ESA)的城市快速路。由于城市快速路的径流系数大、污染物累积量高、污染物成分复杂,导致城市快速路造成的潜在环境污染问... 详细信息

随着城市化、人口增长以及社会经济的迅猛发展,中国的城市生态环境日趋恶化。深圳市正在建设一条经过环境敏感区(ESA)的城市快速路。由于城市快速路的径流系数大、污染物累积量高、污染物成分复杂,导致城市快速路造成的潜在环境污染问题格外严峻。鉴于ESA极易受到人为干扰,因此应给予特别关注。为了评估该城市快速路沿线的环境敏感性,并最大限度地减少道路建设及未来通行对周边生态系统的影响,本文借助地理信息系统(GIS)对相关区域的环境敏感性进行了评估。最终的ESA分布图被划分为4个环境敏感度等级。结果表明该快速路的大部分路段(11.93 km)经过高度敏感区,占快速路总里程的52.3%,且90%以上的路段经过ESA。本文为基于低影响开发技术的初期降雨径流处理设施的布局方案优化提供重要指导,以最大限度地减小道路径流污染对周边生态环境的影响。

关键词：环境敏感区城市快速路地理信息系统低影响开发

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treatment of swine wastewater in aerobic granular reactors： comparison of different seed granules as factors

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Frontiers of environmental Science & Engineering 2015年第6期9卷 1139-1148页

作者： Lin LIU Qiyu YOU Valerie GIBSON Xu HUANG Shaohua CHEN Zhilong YE Chaoxiang LIU Key Laboratory of Urban Pollutant Conversion Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China Ningbo Urban Environment Observation and Research Station Chinese Academy of Sciences Ningbo 315000 China State Environmental Protection Key Laboratory of Microorganism Application and Risk Control Tsinghua University Beijing 100084 China

The granulation process, physic-chemical properties, pollution removal ability and bacterial com- munities of aerobic granules with different feed-waste- water （synthetic wastewater, R1; swine wastewater, R2）, and the change trend of some parameters of two types of granules in long-term operated reactors treating swine wastewater were investigated in this experiment. The result indicated that aerobic granulation with the synthetic wastewater had a faster rate compared with swine waste- water and that full granulation in R 1 and R2 was reached on the 30th day and 39th day, respectively. However, although the feed wastewater also had an obvious effect on the biomass fraction and extracellular polymeric sub- stances of the aerobic granules during the granulation process, these properties remained at a similar level after long-term operation. Moreover, a similar increasing trend could also be observed in terms of the nitrogen removal efficiencies of the aerobic granules in both reactors, and the average specific removal rates of the organics and ammonia nitrogen at the steady-state stage were 35.33mg.g^-1 VSS and 51.46mg.g^-1 VSS for R1, and 35.47mg.g^-1 VSS and 51.72mg.g^-1 VSS for R2, respectively. In addition, a shift in the bacterial diversity occurred in the granulation process, whereas bacterial communities in the aerobic granular reactor were not affected by the seed granules after long-term operation.

关键词： aerobic granules livestock wastewater,sequencing batch reactor biological wastewater treatment,bacterial community

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Genotoxicity removal of reclaimed water during ozonation

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Journal of environmental Sciences 2014年第6期26卷 1243-1248页

作者： Xin Tang Qianyuan Wu Yang Yang Hongying Hu Environmental Simulation and Pollution Control State Key Joint Laboratory State Environmental Protection Key Laboratory of Microorganism Application and Risk Control School of Environment Tsinghua University Shenzhen Laboratory of Microorganism Application and Risk Control Graduate School at Shenzhen Tsinghua University

Genotoxicity in wastewater and reclaimed water now is gaining increased attention because of genotoxins＇ potential damage to the ecosystem and human health. The effect of ozonation on genotoxicity in reclaimed water was investigated. It was found that ozonation decreased the genotoxicy dramatically in three tertiary treatment plants. In the further batch ozonation experiment in laboratory, secondary effluent sample used exhibited the genotoxicity of （41.1 ± 4.1） μg 4NQO/L. Ozonation with a dose of 10 mg O3/L completely removed the genotoxicity in secondary effluent. However, after ozonation, the dissolved organic carbonvalue of the sample didn＇t change much but the specific ultraviolet absorbance （SUVA） value dropped sharply. With the help of Fourier transform infrared spectroscopy, ozonation was found to change chemical aliphatic carbon and C-O of the dissolved arganic matter, which might be the reason of the significant decreases of SUVA and genotoxicity.

关键词： ozonation genotoxicy specific ultraviolet absorbance fourier transform infrared spectroscopy

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Effect of different molecular weight organic components on the increase of microbial growth potential of secondary effluent by ozonation

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Journal of environmental Sciences 2014年第11期26卷 2190-2197页

作者： Xin Zhao Hong-Ying Hu Tong Yu Chang Su Haochi Jiang Shuming Liu Environmental Simulation and Pollution Control State Key Joint Laboratory School of Environment Tsinghua University State Environmental Protection Key Laboratory of Microorganism Application and Risk Control Graduate School at Shenzhen Tsinghua University College of Environment and Resources Inner Mongolia University

Ozonation has been widely applied in advanced wastewater treatment. In this study, the effect of ozonation on assimilable organic carbon （AOC） levels in secondary effluents was investigated, and AOC variation of different molecular weight （MW） organic components was analyzed. Although the removal efflciencies were 47%-76% and 94%-100% for UV2s4 and color at ozone dosage of 10 mg/L, dissolved organic carbon （DOC） in secondary effluents was hardly removed by ozonation. The AOC levels increased by 70%-780% at an ozone dosage range of 1-10 mg/L. AOC increased significantly in the instantaneous ozone demand phase, and the increase in AOC was correlated to the decrease in UV254 during ozonation. The results of MW distribution showed that, ozonation led to the transformation of larger molecules into smaller ones, but the increase in low MW （〈1 kDa） fraction did not contribute much to AOC production. The change of high MW （〉100 kDa and 10-100 kDa） fractions itself during ozonation was the main reason for the increase of AOC levels. Furthermore, the oxidation of organic matters with high MWs （〉 100 kDa and 10-100 kDa） resulted in more AOC production than those with low MWs （1-10 kDa and 〈1 kDa）. The results indicated that removing large molecules in secondary effluents could limit the increase of AOC during ozonation.

关键词： Wastewater reclamation and reuse Ozonation Assimilable organic carbon （AOC）Molecular weight distribution Biological stability

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EDTA fouling in dead-end ultrafiltration of low level radioactive wastewater

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Nuclear Engineering and Design 2015年 295卷 276-282页

作者： Lixia Niu Xue Zhang Xuan Zhao Hongying Hu Collaborative Innovation Center of Advanced Nuclear Energy Technology Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 PR China State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC) Graduate School at Shenzhen Tsinghua University Shenzhen 518055 PR China Environmental Simulation and Pollution Control State Key Joint Laboratory School of Environment Tsinghua University Beijing 100084 PR China

EDTA is widely used as a detergent, and finally enters into wastewater. The influence of EDTA on ultrafiltration of low level radioactive wastewater (LLRW) was investigated under different operation conditions. As the main organic pollutant, EDTA led to unrecoverable membrane fouling and the normalized flux decreased from 100% to 85% depending on its concentration. The clogging caused by EDTA increased the surface roughness of the membrane, leading to the flux reduction. Both nuclide rejections and depositions on the membrane surfaces were enhanced with EDTA addition, due to the strong complexation of the nuclides with EDTA. However, Ag deposition on the membrane decreased slightly in the presence of EDTA, which may be caused by the stronger attraction of Ag to the unmodified membrane than that to the EDTA-modified one. Transmembrane pressure (TMP) and molecular weight cut off (MWCO) of membranes had negligible effects on membrane fouling, while the nuclide rejections by membrane and the depositions of nuclides on membrane both decreased significantly when the TMP increased to 0.2 MPa and MWCO increased from 5 kDa to 30 kDa. Based on these results, it clearly showed that EDTA even at a low concentration had strong effects on the performance of UF treating LLRW. Therefore, it is suggested for industrial application that pretreatments to reduce EDTA or alkaline/ultrasonic washing involved in UF process were necessary to reduce the nuclide depositions on the membrane surfaces and irradiation dose of membrane surface.

关键词： S. Waste management

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Removal of pharmaceutical and personal care products by sequential ultraviolet and ozonation process in a full-scale wastewater treatment plant

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Frontiers of environmental Science & Engineering 2014年第1期8卷 62-68页

作者： Qian SU Jun HUANG Shuguang LU Shubo DENG Bin WANG Wentao ZHAO Zhaofu QIU Gang YU State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process School of Resources and Environmental Engineering East China University of Science and Technology Shanghai 200237 China School of Environment THU - VEOLIA Joint Research Center for Advanced Environmental Tec'hnolo~y Tsinghua'University Beijing 100084 China State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC) Tsinghua University Beijing 10084 China

The application of appropriate advanced treat- ment process in the municipal wastewater treatment plants （WWTPs） has become an important issue considering the elimination of emerging contaminants, such as pharma- ceutical and personal care products （PPCPs）. In the present study, the removal of 13 PPCPs belonging to different therapeutic classes by the sequential ultraviolet （UV） and ozonation process in a full-scale WWTP in Beijing was investigated over the course of ten months. Most of the target PPCPs were effectively removed, and the median removal efficiencies of individual PPCPs, ranging from -13% to 89%, were dependent on their reaction rate constants with molecular ozone. Noticeable fluctuation in the removal efficiencies of the same PPCPs was observed in different sampling campaigns. Nevertheless, the sequential UV and ozonation process still made a significant contribution to the total elimination of most PPCPs in the full-scale WWTP, by compensating for the poor or fluctuant removal performance of PPCPs by biologic treatment process.

关键词： PPCPs advanced treatment ozone fluctua-tion removal contribution

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Bacterial Communities Associated with An Occurrence of Colored Water in An Urban Drinking Water Distribution System

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Biomedical and environmental Sciences 2014年第8期27卷 646-650页

作者： WU Hui Ting MI Zi Long ZHANG Jing Xu CHEN Chao XIE Shu Guang State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC) Tsinghua University School of Environment Tsinghua University State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University

This study aimed to investigate bacterial community in an urban drinking water distribution system （DWDS） during an occurrence of colored water. Variation in the bacterial community diversity and structure was observed among the different waters, with the predominance of Proteobacteria. While Verrucomicrobia was also a major phylum group in colored water. Limnobacter was the major genus group in colored water, but Undibacterium predominated in normal tap water. The coexistence of Limnobacter as well as Sediminibacterium and Aquobocterium might contribute to the formation of colored water.

关键词： Bacterial Communities Associated with An Occurrence of Colored Water in An Urban Drinking Water Distribution System

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