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Toxicity-based assessment of the treatment performance of wastewater treatment and reclamation processes

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Journal of Environmental Sciences 2012年第6期24卷 969-978页

The reclamation and reuse of wastewater is one of the possible ways to relieve the serious fresh water resource crisis in China. Efficient reclamation treatment technologies ensure the safe reuse of reclaimed water. In order to screen out and evaluate technologies appropriate for reclamation treatment, a great deal of efforts have been brought to bear. In the present study, a toxicity-based method including a Photobacterium phosphoreum test for acute toxicity and SOS/umu test for genotoxicity, accompanied by the traditional physicochemical parameters DOC （dissolved organic carbon） and UV254 （absorbance at 254 nm）, was used to measure the treatment performance of different reclamation processes, including the anaerobic-anoxic-oxic biological process （A^2O） and subsequent physical/chemical reclamation processes （ultrafiltration, ozonation, chlorination）. It was found that for the secondary effluent after the Aao process, both the toxicity and physicochemical indices had greatly decreased compared with those of the influent. However, chemical reclamation processes such as ozonation and chlorination could possibly raise toxicity levels again. Fortunately, the toxicity elevation could be avoided by optimizing the ozone dosage and using activated carbon after ozonation. It was noted that by increasing the ozone dosage to 10 mg/L and employing activated carbon with more than 10 min hydraulic retention time, toxicity elevation was controlled. Furthermore, it was shown that pre-ozonation before activated carbon and chlorination played an important role in removing organic compounds and reducing the toxicity formation potential. The toxicity test could serve as a valuable tool to evaluate the performance of reclamation processes.

关键词： wastewater reclamation acute toxicity genotoxicity toxicity assessment

Acute toxicity evaluation for quinolone antibiotics and their chlorination disinfection processes

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Journal of Environmental Sciences 2014年第9期26卷 1837-1842页

作者： Min Li dongbin wei Yuguo Du State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of Sciences

Acute toxicity of 21 quinolone antibiotics was monitored using photobacterium Vibriofischeri assay. The minimum IC20 （inhibitory concentration for 20% luminescence elimination） was obtained at the least 18.86 μmol/L for the tested quinolones. A quantitative structure-activity relationship model was established to investigate the possible mechanism for the acute toxicity. The critical physicochemical descriptors, describing a and atom electronegativity, implied that the electron transfer might occur between the quinolones and photobacterium V. fischeri. Although the quinolones exhibited limited acute toxicity to photobacterium, toxicity elevation was detected after their chlorination. Hence, chlorination disinfection treatment of quinolone-containing water should be of concerns.

关键词： QuinolonesAcute toxicityQSARMechanismChlorination

Physical and Numerical Simulation for Inner Crack Healing in Metals

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上海交通大学学报 2004年第Z2期38卷 130-135页

作者： Jingtao HAN dongbin wei Yongjun ZHANG School of Material Science and Engineering UST Beijing 100083 P.R.China University of Wollongong NSW 2522 Australia SHOUGANG Research Institute of Technology Beijing 100041 P.R.China

The research purpose on the healing of inner crack in metallic materials is to provide an effective approach for improving their properties and prolonging their lifetime. The crack healing process of 20MnMo steel with inner pre-crack was analyzed. It was found that all inner cracks could be healed in different degree. There were very fine ferrite grains in healing region. The micro-crack healing process in single crystal of BBC-Fe was simulated by the molecule dynamics method, which showed that the critical temperature of crack healing in BBC-Fe is 673K. There were micro-voids, dislocations and twins left after crack healing.

关键词： metal inner crack healing simulation

An alternative total synthesis of solamargine

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Science China Chemistry 2012年第7期55卷 1247-1251页

作者： wei GuoHua wei dongbin DU YuGuo State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences(CAS)Beijing 100085China

Solamargine, （25R）-3β-（O-a-L-rhamnopyranosyl-（1--2）-[O-a-L-rhamnopyranosyl-（1--4）]-β-D-glucopyranosloxy}-22a-N- spirosol-5-ene, isolated from the berries of solanum aculeastrum, has been synthesized in 26.8% overall yield. First glycosylation before N-cyclization significantly facilitated synthesis of the desired molecule. We anticipate that this work will provide a new approach to access solamargine and its diversified analogues.

关键词： solasodine natural products solamargine glycosides

Characterization of dissolved organic matter fractions and its relationship with the disinfection by-product formation

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Journal of Environmental Sciences 2009年第1期21卷 54-61页

作者： ZHANG Hua QU Jiuhui LIU Huijuan wei dongbin Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Graduate University of Chinese Academy of Sciences Beijing 100039 China

Dissolved organic matter （DOM） has been identified as precursor for disinfection by-products （DBPs） formation during chlorination. Recently, it has been demonstrated that the characteristics of DOM influence the DBPs formation mechanism. A study was, therefore, initiated to investigate the effects of DOM fractions on DBPs formation mechanism. In the chlorination process, organic acids are dominant precursors of total thihalomethanes （TTHM） because of the vc-o and unsaturated structures. Furthermore, the TTHM formation of organic acids was affected by pH more greatly. Based on the fluorescence spectroscopy analysis, DOM fractions contained several fluorescence substances. During chlorination, humic acid-like substances were found to exhibit high chlorine reactivity and hydrophobic organics decomposed to smaller molecules faster than hydrophilic organics even at lower chlorine dosages. Unlike hydrophobic fractions, hydrophilic organics showed no toxicity following chlorination, suggesting that the toxic structures in hydrophihc organics showed high chlorine reactivity during chlorination.

关键词： disinfection by-products chlorination characteristics dissolved organic matter

Sequential use of ultraviolet light and chlorine for reclaimed water disinfection

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Journal of Environmental Sciences 2011年第10期23卷 1605-1610页

作者： Xiujuan Wang Xuexiang Hu Chun Hu dongbin wei State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Several disinfection processes of ultraviolet （UV）, chlorine or UV followed by chlorine were investigated in municipal wastewater according to the inactivation of Escherichia coli, Shigella dysenteriae and toxicity formation. The UV inactivation of the tested pathogenic bacteria was not affected by the quality of water. It was found that the inactivated bacteria were obviously reactivated after one day in dark. Fluorescent light irradiation increased the bacteria repair. The increase of UV dosage could cause more damage to bacteria to inhibit bacteria self-repair. No photoreactivation was detected when the UV dose was up to 80 mJ/cm2 for E. coli DH5ct, and 23 mJ/cm2 for S. dysenteriae. Nevertheless, sequential use of 8 mJ/cm2 of UV and low concentration of chlorine （1.5 mg/L） could effectively inhibit the photoreactivation and inactivate E. coli below the detection limits within seven days. Compared to chlorination alone, the sequential disinfection decreased the genotoxicity of treated wastewater, especially for the sample with high NH3-N concentration.

关键词： chlorine disinfection sequential disinfection UV disinfection photoreactivation genotoxicity wastewater reclamation

Research progress of disinfection and disinfection by-products in China

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Journal of Environmental Sciences 2019年第7期31卷 52-67页

作者： Xuefeng Sun Miao Chen dongbin wei Yuguo Du State Key Laboratory of Environmental Chemistry and Eco-Toxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences

Disinfection is an indispensable water treatment process for killing harmful pathogens and protecting human health. However, the disinfection has caused significant public concern due to the formation of toxic disinfection by-products(DBPs). Lots of studies on disinfection and DBPs have been performed in the world since 1974. Although related studies in China started in1980 s, a great progress has been achieved during the last three decades. Therefore, this review summarized the main achievements on disinfection and DPBs studies in China, which included:(1) the occurrence of DBPs in water of China,(2) the identification and detection methods of DBPs,(3) the formation mechanisms of DBPs during disinfection process,(4) the toxicological effects and epidemiological surveys of DBPs,(5) the control and management countermeasures of DBPs in water disinfection, and(6) the challenges and chances of DBPs studies in future. It is expected that this review would provide useful information and reference for optimizing disinfection process, reducing DBPs formation and protecting human health.

关键词： Disinfection Disinfection by-products Identification Formation mechanisms Toxicology Control

Acute toxicity formation potential of benzophenone-type UV filters in chlorination disinfection process

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Journal of Environmental Sciences 2014年第2期26卷 440-447页

作者： Qi Liu Zhenbin Chen dongbin wei Yuguo Du School of Material Science and Engineering Lanzhou University of Technology State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials Lanzhou University of Technology

Benzophenones （BPs） are a class of widely used UV filters, which have been frequently detected within multiple environmental matrices. Disinfection is a necessary process in water treatment processes. The transformation behaviors and toxicity changes of 14 BP-type UV filters during chlorination disinfection treatment were investigated in this study. A new index, the acute toxicity formation potential, was proposed to evaluate the toxicity changes and potential risks of BP-type UV filters during chlorination treatment. It was found that 13 of 14 BP-type UV filters exhibited toxicity decreases in the chlorination disinfection process, more or less, while one showed a toxicity increase. The toxicity changes were dependent on substitution effects, such that 2,4-di-hydroxylated or 3-hydroxylated BPs exhibited significant toxicity decreases after chlorination treatment due to the ready cleavage of the aromatic ring. Importantly, the acute toxicity changes could be duplicated in an ambient water matrix.

关键词： acute toxicity formation potential benzophenones UV filters chlorination photobacterium assay

A toxicity-based method for evaluating safety of reclaimed water for environmental reuses

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Journal of Environmental Sciences 2014年第10期26卷 1961-1969页

作者： Jianying Xu Chuntao Zhao dongbin wei Yuguo Du College of Resource Environment and Tourism Capital Normal University State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

A large quantity of toxic chemical pollutants possibly remains in reclaimed water due to the limited removal efficiency in traditional reclamation processes. It is not enough to guarantee the safety of reclaimed water using conventional water quality criteria. An integrated assessment method based on toxicity test is necessary to vividly depict the safety of reclaimed water for reuse. A toxicity test battery consisting of lethality, genotoxicity and endocrine disrupting effect was designed to screen the multiple biological effects of residual toxic chemicals in reclaimed water. The toxicity results of reclaimed water were converted into the equivalent concentrations of the corresponding positive reference substances（EQC）. Simultaneously, the predicted no-effect concentration（PNEC） of each positive reference substance was obtained by analyzing the species sensitivity distribution（SSD） of toxicity data. An index ＂toxicity score＂ was proposed and valued as 1, 2, 3, or 4 depending on the ratio of the corresponding EQC to PNEC. For vividly ranking the safety of reclaimed water, an integrated assessment index ＂toxicity rank＂ was proposed, which was classified into A, B, C, or D rank with A being the safest. The proposed method was proved to be effective in evaluating reclaimed water samples in case studies.

关键词： Toxicity Safety Water quality Reclaimed water