基于SOS/umu生物测试评价不同炭龄活性炭对遗传毒性物质的去除效果

活性炭处理是目前水厂去除有机物最有效的手段,换炭的主要依据是浊度、COD_(Mn)、UV_(254)等常规指标。研究表明,饮用水中还存在着具有遗传毒性的物质,研究不同炭龄活性炭对遗传毒性物质的去除效果对于指导换炭具有重要意义。采用SOS/umu生物毒性测试方法筛查了北方3个自来水厂不同炭龄、工艺的活性炭进出水的遗传毒性效应。结果显示:活性炭对水中遗传毒性物质的去除能力随着炭龄的增加而下降,高炭龄活性炭出水中遗传毒性物质反而会升高;臭氧工艺的存在会降低活性炭去除遗传毒性物质能力,但臭氧工艺对水中遗传毒性有一定去除作用,能够降低活性炭的处理负荷;再生炭对于水中遗传毒性物质也有较好的去除效果,低温情况下活性炭去除遗传毒性物质的能力与高温情况下相比会有明显下降;同时对于高龄炭低温情况下其向水中释放的遗传毒性物质也会比高温时少很多。     

北京市第九水厂净水工艺评价和优化研究

针对北京第九水厂的水源水质和处理工艺现状,主要研究了现有常规工艺混合、反应和煤、砂过滤的运行优化,颗粒活性炭吸附过滤的应用特性和活性炭优化选型,现有水净化工艺各处理单元对水质的生物细胞毒性(以中国仓鼠卵巢细胞,CHO cells为靶细胞)的影响、高锰酸钾预氧化对水源中藻类污染物引起的嗅、味去除效果等内容,并得出如下结论: (1)第九水厂一期工程预处理采用机械加速澄清池,可通过调节搅拌强度、加药和投加助凝剂等手段提高水处理效果,出水水质较易控制,浊度一般可控制在1NTU以下。二、三期工艺混合较充分,但反应池短流和水量不稳定造成的反应强度不足,絮体沉降性能差,特别在原水浊度低时沉淀池去浊效率低。但通过技术改进和强化沉淀池冲洗可提高反应和沉淀效果。 (2)二期工艺的气、水反冲洗滤池采用了均质滤料的深层滤床滤池过滤,效果优于一期工艺双层滤料的虹吸滤池。虽然前者进水浊度高于后者,但其出水浊度一般可控制在0.2 NTU,后者滤池出水浊度0.3～0.4 NTU。通过水中颗粒计数也发现,对0.2μm以上颗粒的去除,匀质滤料滤池可达95％以上,而双层滤料的虹吸滤池只有50％左右。 (3)研究发现,常规处理与活性炭吸附结合是降低饮用水生物毒性,提高水质安全性的有效手段。水源的水质较好,但预加氯后其生     

上向流O3-BAC工艺处理微污染湖泊水研究

以我国华东地区某湖泊水为原水,进行中试规模的上向流臭氧生物活性炭（O3-BAC ）工艺研究,考察该工艺去除水中有机物的能力,以及工艺出水的生物稳定性和化学安全性。研究结果表明：该工艺能有效去除有机物、氨氮和消毒副产物前体物,同时能提高出水的生物稳定性。该工艺出水CODMn 、UV254和DOC的平均值分别为2.31 mg/L、0.034 cm -1和1.76 mg/L ,平均去除率为53.4％、67.3％和65.1％;三卤甲烷,卤乙酸和亚硝胺类副产物生成潜能的平均去除率分别为50.3％,59％和96.6％;AOC平均去除率为54.5％;工艺出水BDOC仅为0.56 mg/L ;且出水未检出BrO3-。因此,O3-BAC工艺适合处理该湖泊水且出水水质安全。     

臭氧-生物活性炭控制有机物和消毒副产物研究

南方某水厂采用的臭氧-生物活性炭给水深度处理工艺稳定运行了6年,为了解工艺长期运行过程中在活性炭性能指标下降后,是否还能有效地去除有机物和消毒副产物,开展了试验研究。重点考察臭氧-生物活性炭对水中有机物和氯化消毒副产物的去除效果,通过与常规处理出水水质的对比,探讨其去除有机物和消毒副产物的优势。结果表明,臭氧-生物活性炭是一个长期有效的去除有机物和氯化消毒副产物的控制手段。该工艺对CODMn、TOC、UV254的去除率分别为43.2%、24.0%、58.8%;对THMsFP去除率为40.1%;对三氯甲烷和三氯乙醛的去除率分别达到54.5%和70.7%。在臭氧-生物活性炭组合处理工艺中,活性炭池是去除有机物和消毒副产物的关键工艺。     

密云区农村生活饮水现状分析及对策

为确保密云区农村饮水卫生质量,对水源的保护、水质处理、水质监测及水厂管理等进行了分析.其中水质处理中的消毒工艺是保证卫生质量的主要环节。密云区的实际情况调查表明,保证卫生安全的主要手段是:①采用水源净水工艺去除或降低原水中对人体有害的悬浮物质、胶体、有害细菌、病毒以及溶解于水中对人体有害的物质;②对水中的微生物进行消毒处理。目前,主要采取二氧化氯、臭氧消毒进行水处理,通过对二氧化氯、臭氧消毒工艺进行科学设计,密云区农村饮水微生物指标的合格率已明显提高。密云区通过加强水源保护、强化水质处理工艺、建立健全水质监测体系等.实时掌握水源地水量水质状况,实现了保证农民饮水达到GB 5749-2006《生活饮水卫生标准》要求。     

某高校学生公寓洗浴废水回用实例分析

采用实例分析法,以某高校建设中水站为例,从中水原水水源选取及其水量水质、工艺流程和主要设备、运行管理、出水水量和水质及经济效益等方面进行分析,结果表明:洗浴废水属于优质杂排水,可作为中水水源,其水量水质相对稳定;膜生物反应器MBR工艺适用于高校学生公寓洗浴废水的处理,具有工艺流程简单、操作维护方便及占地面积小等特点;洗浴废水中主要污染物为浊度、五日生化需氧量BOD5、化学需氧量COD及总大肠菌群等,MBR工艺对其可有效去除,出水水量和水质可满足冲厕和绿化需求,每年至少可节约自来水量3万9 181m~3,以给无市政中水可引入的新建高校园区的中水回用工程提供可借鉴的经验     

微污染水源水生物预处理及后续工艺的生化延伸效应除污染研究

许多城市的饮用水水源受到污染 ,采用弹性立体填料的生物接触氧化技术是一种经济高效、运行稳定、便于管理的去除原水中污染物质的生物预处理工艺。在由生物预处理和常规水处理工艺组成的净水系统中 ,应充分利用生物预处理池出水中的生化延伸效应提高其后续沉淀池和砂滤池等的除污染效果 ,即不应对生物预处理池出水再预加氯。对污染程度较高的微污染原水 ,还应对砂滤池出水再进行生物活性炭等深度处理     

臭氧催化氧化改善水质安全性指标中试与生产性研究

从水的生物稳定性、遗传毒性、颗粒物去除、臭氧氧化副产物以及催化剂的稳定性等方面研究了臭氧催化氧化-生物活性炭技术在净水处理过程中的安全性问题.结果表明,催化剂具有优良的物理化学稳定性,能够催化臭氧氧化进一步控制AOC及其前质,减小了活性炭的污染物负荷;与生物活性炭联用可以明显减小有害有机物穿透水处理工艺的能力,进一步消减了水的遗传毒性;联用工艺可以显著地去除水中与致病原生动物相关性极大的2～10 μm颗粒物,进一步提高了饮用水的卫生安全性;催化剂对剩余臭氧的消减抑制了BrO-3生成.     

嘉兴市贯泾港水厂工艺运行介绍

近年来,因受水源条件限制,嘉兴地区给水厂普遍采用生物预处理-加强常规处理-臭氧-生物活性炭滤池组合工艺,使出厂水水质有了明显的改善和提高.嘉兴市贯泾港水厂在此基础上又进行了新的探索,引入臭氧催化氧化-上向流生物活性炭-后置微絮凝强化砂滤新型组合工艺,有效降低了出水消毒副产物和微生物泄漏风险,出厂水水质达到了<生活饮用水卫生标准>(GB 5749-2006)以及浙江省现代化水厂的出水水质标准要求.     

饮用水消毒副产物卤乙腈的研究

卤乙腈(HANs)普遍存在于饮用水中,且卤乙腈比三卤甲烷(THMs)和卤乙酸(HAAs)等消毒副产物具有更强的遗传毒性、细胞毒性和致癌性。介绍了卤乙腈的种类毒性、分布情况及卤乙腈前体物的种类、卤乙腈的生成过程、卤乙腈的含量控制。其中消毒副产物生成的种类和数量主要与水源水的水质特性、所使用的消毒剂种类和水处理工艺与工况有关,概述了控制卤乙腈前体物与改良消毒工艺及去除已生成的卤乙腈,以减少饮用水中卤乙腈的浓度水平。     

北方某水厂原水及处理过程中Ah受体效应的行为研究

以北方某城市给水厂的自来水为研究对象,采用重组基因酵母测定法对不同处理工艺单元出水的芳香烃受体(AhR)效应进行了检测.检测结果表明,原水具有明显的AhR效应经常规工艺处理后AhR效应不能得到很好的去除,而经臭氧-活性炭深度处理后,92%的AhR效应能够被有效去除.     

Bioassays and biomarkers for ecotoxicological assessment of reclaimed municipal wastewater.

The aim of this work was to examine the ecotoxicity of reclaimed wastewater by the use of bioassays and the determination of immunological parameters. Secondary and tertiary mucicipal wastewater samples were examined for their physicochemical and microbiological characteristics as well as for their endotoxin concentrations. The ecotoxicological characteristics were assessed by a battery of bioassays, using Vibrio fischeri, Daphnia magna and Tetrahymena thermophilla as test species and phytotoxicity. The mitogenic responses of mouse splenocytes were as well used as bioassay. The cytokines of IL-1, IL-2, IL-10, IFNgamma and TNFalpha, were also determined in the supernatant of splenocyte cultures and served as molecular biomarkers. All bioassays exhibited decrease of the ecotoxicological responses after tertiary treatment. However, mitogenic responses were proved to be more sensitive. IL-1 increased, while IL-2 production was unaffected. The fact that IL-10 production increased in response to secondary treated effluents in conjunction with the increased endotoxin levels, suggest Th2 type immune responses. Although results obtained from the toxicity bioassays after the tertiary treatment showed comparable results to those of controls, cytokine levels indicated the induction of immune response even after tertiary treatment. Consequently, cytokine production could be used as a sensitive biomarker for the evaluation of treatment efficiency of the reclaimed wastewaters intended for reuse.     

Assessment of Estrogen (ER) and Aryl Hydrocarbon Receptor (AhR) Mediated Activities in Organic Sediment Extracts of the Detroit River,Using In Vitro Bioassays Based on Human MELN and Teleost PLHC-1 Cell Lines

Binding to estrogen and aryl hydrocarbon receptors (ER and AhR) is a possible mechanism for a compound to mediate endocrine-disrupting effects. In the present study, substances contained in sediment organic fractions from the Detroit River were screened for their ability to bind ER and/or AhR. Two in vitro bioassays were used: MELN cells, consisting of human breast cancer cells (MCF-7) stably transfected with the luciferase reporter gene, to assess the binding to ER, and cultured fish hepatocytes, PLHC-1, to measure the AhR-mediated induction of 7-ethoxyresorufin-O-deethylase (EROD). Chemical analyses of the sediment extracts were performed to examine relationships with the biological responses.Significant ER- and AhR-activities were mostly found in the most polar fraction (containing mostly PAHs). The five strongest estrogenic extracts were also the most efficient to induce EROD activity. The correlation between PAHs contamination level and biological responses suggests that the most polluted areas contain a mixture of both estrogenic and EROD-inducing compounds or, alternatively, compounds able to bind ER and AhR, such as PAHs, would be responsible for the observed activities.     

Ecotoxicological risks from dissolved organic contaminants in a contaminated bay: Combining passive sampling with in vivo bioassays

Innovative and robust methods are needed to evaluate the risks to native aquatic organisms exposed to organic compounds released from contaminated sediments. In the present study, we deployed semi-permeable membrane devices (SPMDs) above sediments in a contaminated harbor at a location in the Laurentian Great Lakes (i.e. Owen Sound Bay) and prepared extracts from these passive samplers for analysis of organic contaminants and for toxicity testing using early life stages of Japanese medaka (Oryzias latipes) and lake whitefish (Coregonus clupeaformis). The concentrations of several classes of organic contaminants estimated from analysis of the SPMD extracts indicated that several polynuclear aromatic hydrocarbon (PAHs) were present in the water column in the inner harbor of Owen Sound Bay at concentrations higher than water quality standards for the protection of aquatic life. Several medaka exposed to the SPMD extract from the inner harbor as well as a positive control compound, benzo[a]pyrene, developed yolk sac edema. However, whitefish did not show the same response. Overall, these data indicate this contamination could contribute to toxicity in sensitive species. The coupling of passive sampling and in vivo bioassays with early life stages of fish shows promise as a method to assess the potential for risks from biologically available fractions of organic contaminants in water. A novel aspect of the present study is the development of a bioassay procedure with early life stages of lake whitefish involving exposures at low temperatures over durations of time that are longer than the bioassays with more conventional model fish species.     

Passive samplers for chemical substance monitoring and associated toxicity assessment in water

The European legislation, and in particular the Water Framework Directive requires the development of cost efficient monitoring tools that can provide the required information for the assessment of water contamination. Passive sampling methods represent one of the novel tools that have a potential to be used in various regulatory monitoring programmes aimed at assessing the levels of chemical pollutants. These methods are particularly interesting for sampling polar organic pollutants in water because they provide representative information of the water quality over extended time periods (days to weeks) in environments with fluctuating contaminant concentrations. This is achieved by integrative sampling of pollutants over the whole sampler deployment period. These tools can be coupled to toxicity testing using bioassays that give information on toxic and ecotoxic hazards associated to substances that are present, these substances being identified or not. In this study the polar organic chemical integrative sampler (POCIS) was used in surface water to evaluate the water contamination by polar organic compounds and their potential toxicity.     

上海市浦东给水厂两虫去除研究

采用EPA1623法(免疫磁分离及荧光染色法)对上海市几家典型的给水厂的水源水、出厂水、管道水中贾第鞭毛虫和隐孢子虫的分布状况进行了测定分析,并对给水厂净水过程中不同操作单元对两虫的去除效果进行了研究.研究表明:上海浦东给水厂水源水中存在贾第鞭毛虫与隐孢子虫,但其密度分别维持在0～6个/10 L和0～8个/10 L的低水平,而出厂水与管道水中均未检出两虫;给水厂净水过程中,混凝沉淀对两虫具有明显的去除效果.     

Assessing the elimination of estrogenic activity in advanced wastewater treatment with a reporter gene-based bioassay.

Estrogen-like chemicals, so-called xenoestrogens, have become a topic of concern because they are potentially capable of disturbing the hormonal balance of wildlife and humans. Effluents of wastewater treatment plants (WWTPs) are presumably the major source of xenoestrogens in the aquatic environment. In this study, we investigated eight WWTPs with respect to their input, elimination efficiency, and output of estrogenic activity by means of a reporter gene-based bioassay. All WWTPs employed activated sludge treatment with nitrification/denitrification and tertiary treatment (second nitrification and/or filtration). Estradiol equivalents (EEQs) in the influents of the WWTPs were between 5.7 and 65.8 ng/L. The greatest inputs were found in plants treating pure domestic sewage and in samples collected in winter. Process waters either had no estrogenic activity or EEQs in the range of raw sewage, depending on the source of the process water. EEQs of effluents ranged from mostly below quantification limit (0.8 ng/L) to a maximum of 5.4 ng/L in secondary and 1.4 ng/L in tertiary effluents. These findings demonstrate the elimination efficiency of the activated sludge treatment and the further improvement by additional tertiary treatment. However, several concentrated effluents elicited little, but detectable estrogenic responses in the bioassay.     

壬基酚聚氧乙烯醚(NPEOs)在净水厂中的监测

低浓度内分泌干扰物长期作用会对人体健康产生不可忽视的负面影响.较详细地研究了北方某给水厂现有净水处理工艺对低浓度NPEOs的控制特性,结果表明,该厂常规工艺单元(无预氯化)对NPEOs(聚合度n＝4～15)基本上没有去除作用,后续活性炭单元对NPEOs的去除作用也不是很明显,有待进一步研究.由于氯的强氧化作用的存在,加氯能明显降低水中的NPEOs浓度.     

Behaviour of bisphenol A (BPA), 4-nonylphenol (4-NP) and 4-nonylphenol ethoxylates (4-NP1EO, 4-NP2EO) in oxidative water treatment processes.

Endocrine disrupting chemicals (EDCs) such as natural and synthetic hormones or industrial chemicals can adversely affect the endocrine system at very low concentrations. As such substances can be present in raw water used for drinking-water production, they potentially pose a health risk to humans. In this study laboratory tests were performed to determine removal efficiencies of selected oxidative drinking water treatment processes, namely ozonation (1.4 mg/l O3) and chlorination, using sodium hypochlorite (0.5 mg/l NaClO) and chlorine dioxide (0.4-0.6 mg/l ClO2) under conditions applied in technical plants. 500-300,000 ng/l of bisphenol A (BPA), 4-nonylphenol (4-NP) and 4-nonylphenol-n-ethoxylates (NPnEO) were selected for investigations and measured by HPLC/FLD and HPLC/MS. To investigate possible oxidation by-products, adsorbable organic halogens (AOX) were determined and estrogenic activities were assessed with the help of an estrogen receptor binding assay (YES). Ozonation and chlorination with ClO2 removed both 4-NP and BPA below detection limits, corresponding with AOX and estrogenic activity. Concerning NPnEO ozonation removed NP1EO and NP2EO up to 28% and 30%, respectively, whereas ClO2 showed high removal efficiencies, eliminating >94% and 92%, respectively. NaCIO removed 4-NP and BPA below detection limits, but estrogenic activities increased and AOX could be measured. NP1EO and NP2EO were only marginally reduced corresponding to the slight decrease of estrogenic potential.