饮用水生产中突发性有机磷农药污染事故的在线生物监测

饮用水生产中可能因为水源污染或人为投加的有机磷农药而使水质发生突发性变化,可以利用生物暴露于有机磷农药时运动行为的变化在线预警这类突发性污染事故。研究了大型蚤在不同浓度有机磷农药作用下的行为变化规律。研究结果表明,不同浓度对硫磷、马拉硫磷和敌百虫条件下,大型蚤的运动行为会发生剧烈变化,其强度随水中有机磷农药的浓度和暴露时间增加而逐步减弱;即使在这三种有机磷农药的水相浓度远低于《地表水环境质量标准》(GB 3838—2002)的情况下, 仍然可以观察到大型蚤运动行为的改变,因此可以对突发性有机磷农药污染事故实现安全预警。     

大型溞和日本青鳉在水质在线生物安全预警应用中的比较

讨论了利用大型溞和日本青鳉作为受试生物,通过在线监测两种受试生物行为变化反映水质变化状况的优缺点.结果表明:首先,大型溞对水体污染比日本青鳉更敏感,针对某些污染物的监测水平甚至高于国家地表水标准的限值,而日本青鳉反应水平处于10倍以上地表水标准;其次,在连续监测过程中,大型溞行为变化未表现明显的昼夜规律性,而日本青鳉行为变化具有更明显的生物钟现象;第三,在连续在线监测过程中,大型溞持续监测只能维持7天左右,其续航能力明显弱于日本青鳉的30天以上监测周期.     

饮用水中余氯对大型蚤的急性和慢性毒性

目前我国饮用水生产过程中普遍采用氯消毒,在去除一些有害微生物的同时,会形成一定浓度的余氯。为了监测余氯对用于在线监测的水生生物产生的毒性效应,讨论了饮用水中余氯对大型蚤的急性和慢性毒性。当余氯为0.16 mg/L时,大型蚤24 h存活率为100%,48 h存活率为90%;当余氯达到0.32 mg/L时,大型蚤48 h存活率为30%。在最小致死剂量(MLD=0.16 mg/L) 暴露下,40 d慢性毒性结果显示水中余氯对大型蚤生长和生殖影响显著。因此,可用于实现在线连续监测过量投加后水中高浓度的余氯。而当大型蚤用于毒性的在线生物监测(如突发性事故监测), 或用于监测水质大幅度变化时,应考虑首先消除水中余氯对动物行为生态的影响。     

水源地有机农药在线监测技术的应用研究

使用Aquapod SPE 250在线监测仪开发了9种微量有机农药的在线监测方法,对其在重点饮用水水源地平岗泵站的实际应用进行了研究,并对该仪器的突发污染预警能力进行了测试评估。结果显示,Aquapod SPE 250在线监测阿特拉津、甲萘威、对硫磷、2,4-二氯苯酚、2,4,6-三氯苯酚、五氯酚、苯酚、敌草隆和绿麦隆等农药残留值的检出限较低,满足GB3838-2002《地表水环境质量标准》的要求;平岗泵站2013年1-5月的有机农药残留值虽未超过我国标准,但已超出《欧盟饮用水水质指令》的检出限值;在实际水样中添加阿特拉津标准物质,Aquapod SPE 250的测定光谱异常,仪器出现报警信号,表明该仪器可用于有机农药的突发污染预警。     

突发性水污染事故应急监测体系研究

目前,我国已进入水污染事故的高发期.应急监测体系作为突发性水污染事故处理的重要组成部分,对突发性水污染事故应急监测具有指导作用.本文通过对突发性水污染事故应急监测体系建设的研究,将监测体系分为应急监测预案、装备体系、技术体系、能力体系、信息体系五个部分,为我国突发性水污染事故的监测和管理提供了一种思路.     

河南省水环境自动监测系统研究

基于ArcGIS的河南省水环境在线自动监测系统,主要由基础地理信息、环境信息、查询与发布、污染扩散分析与预警、突发性污染事故应急预案等子系统构成.讨论了开发平台ArcGIS的特点,提出了采用Client/Server和Browser/Server结构相结合的系统架构,实现空间数据的最大程度共享,最终建成一个资源共享、灵活延展的实用GIS系统.     

突发水污染事故对河流水环境安全的影响研究

突发水污染事故往往会对城市供水安全、河流水环境产生重大影响。根据国家环保总局发布的信息表明,在我国因水上交通事故、企业违规或事故排污、公路交通事故、管道破裂等,每年发生的水污染突发事故次数多达几千起,并有逐年增长的趋势。特别是突发性水污染事故,由于其突发性与不确定性,监测与治理困难,造成的危害更加严重。为了减少危害与损失,研究突发性水污染事故对河流的影响规律尤为必。在建立水质模型的基础上,利用离散系数与降解系数的确定方法,以我国南方某河流为背景,假设河流上游发生事故性排放后,计算下游水体中污染物浓度的变化情况。同时对比了不同流量、不同污染强度条件下,下游污染物的迁移扩散规律和对某取水口的影响。研究成果可为河流应对类性突发性水污染事故提供借鉴。     

突发性水环境污染事故监测及对策

当发生突发性水环境污染事故时,要及时进行监测,迅速查明污染物的种类、污染程度和范围以及污染发展趋势,及时、准确地为决策部门控制污染提供可靠依据.     

汾河水库水源水质在线监测预警系统构建

以山西太原汾河水库为研究对象,针对其地表水源水质特征,通过构建地表水源预警框架,以水源在线监测技术为前提,建立了水质在线监测系统,并研发原水水质在线监测及远传软件,实现了水源水质的远程预警和突发应急调度,为地表水源突发污染应急控制预警提供决策依据与技术参考.     

水源地突发污染事件应急监测研究

水源地突发污染事件应急监测,可为事故处理决策部门提供污染物质类别、浓度分布、影响范围及发展态势等信息.分析了水源地污染事故的主要因素,提出了一般水源地突发污染事件应急监测分类、应急监测指标、应急监测方法,以及应急监测方案.     

Daphnia behavioural responses to taste and odour compounds: ecological significance and application as an inline treatment plant monitoring tool.

Continuous monitoring of volatile organic compounds (VOC) in raw water is highly desirable for taste and odour management, but in most treatment plants this capacity is lacking. We used a bbe Daphnia toximeter installed in the Zurich water treatment plant to determine if Daphnia magna could be used to monitor odour compounds in source-water. Trace levels of two widely distributed biogenic VOCs in freshwater: P-cyclocitral and 2(E),4(E),7(Z)-decatrienal were added to the raw water inflow to chambers containing test animals and their behaviour was recorded using a high resolution camera. We observed that each compound elicited a marked short-term increase in Daphnia swimming velocity, but the effect was brief and an acclimation to the compounds was observed after a time period or with repeated additions. The results demonstrate that the toximeter has considerable potential as a tool to monitor certain VOCs in water, and that Daphnia perceive and react to 2(E),4(E),7(Z)-decatrienal and P-cyclocitral at concentrations between 2.5 and 25 microM.     

Toxic response of aquatic organisms to guide application of artemisinin sustained-release granule algaecide

In our previous study, we prepared the granules by embedding artemisinin into alginate-chitosan using microcapsule technology. Thesgranules can release artemisinin sustainably and have a strong inhibitory effect on the growth of both single Microcystis aeruginosa and mixealgae. To safely and effectively use artemisinin sustained-release granules to control algal blooms, the ecotoxicity was studied by assessing theacute and chronic toxicity to Daphnia magna(D. magna) and Danio rerio(D. rerio), along with their antioxidant activities. The results showethat the 48-h median effective concentration(EC50) of pure artemisinin to D. magna was 24.54 mg/L and the 96-h median lethal concentratio(LC50) of pure artemisinin to D. rerio was 68.08 mg/L. Both values were classified as intermediate toxicity according to the Organization foEconomic Co-operation and Development(OECD). The optimal algae inhibitory concentration of artemisinin sustained-release granules(1 g/Lhad low acute toxicity to both D. magna and D. rerio. The sustained-release granules had higher chronic toxicity to D. magna than to D. reriPartial indices of D. magna were inhibited by granules when the concentrations were larger than 0.1 g/L. Low granule concentration had ainductive effect on antioxidant enzyme activities in D. magna and D. rerio. With the increase of the exposure concentration and time, the enzymactivity presented a trend of first increasing and then decreasing, and the overall changes were significant. The change trend and range of enzymactivity indicated that the granules could cause serious oxidative stress to D. magna and D. rerio, and the changes were consistent with the resultof toxicity experimentation.     

A new online monitoring and management system for accidental pollution events developed for the regional water basin in Ningbo, China

Due to urgency of the accidental pollution events (APE) on one side and the variability in water quality data on the other side, a new online monitoring and management system (OMMS) was developed for the purpose of sustainable water quality management and human health protection as well. The Biological Early Warning System (BEWS) based on the behavioral responses (behavior strength) of medaka (Oryzias latipes) were built in combination with the physico-chemical factor monitoring system (PFMS) in OMMS. OMMS included a monitoring center and six monitoring stations. Communication between the center and the peripheral stations was conducted by the General Packet Radio Service (GPRS) network transmission complemented by a dial-up connection for use when GPRS was unavailable. OMMS could monitor water quality continuously for at least 30 days. Once APEs occurred, OMMS would promptly notify the administrator to make some follow up decisions based on the Emergency Treatment of APE. Meanwhile, complex behavioral data were analyzed by Self-Organizing Map to properly classify behavior response data before and after contamination. By utilizing BEWS, PFMS and the modern data transmission in combination, OMMS was efficient in monitoring the water quality more realistically.     

Advanced oxidation of commercial textile biocides in aqueous solution: effects on acute toxicity and biomass inhibition.

In the present study, the decomposition of two biocides used in the textile finishing process with Advanced Oxidation Processes (AOPs) has been studied. Different AOPs, i.e O3/OH-, TiO2/UV-A and Fe2+/H2O2 have been used representing mutually combined components of the chemically and photochemically driven advanced oxidation systems. The course of reaction was examined by changes in chemical oxygen demand (COD), total organic carbon (TOC) and acute toxicity towards the water flea Daphnia magna (assessed in terms of the effective dilution ratio LD50). Particular attention has been paid to determine the inhibitory effect of raw and ozonated biocides on biological activated sludge consortium at concentrations typically encountered in textile finishing effluents. Significant oxidation and mineralization of both biocides could be achieved employing ozonation at pH = 11.5 and heterogeneous photocatalysis (TiO2/UV-A) at pH = 5.0, whereas Fenton's reagent appeared to be less effective in COD and acute toxicity abatement.     

Toxicity of perfluorononanoic acid and perfluorooctane sulfonate to Daphnia magna

In order to study toxicological effects of perfluorononanoic acid(PFNA), perfluorooctane sulfonate(PFOS), and their mixtures(PFNA/PFOS) on Daphnia magna(D. magna), a suite of comprehensive toxicity tests were conducted, including a 48-h acute toxicity test, a 21-day chronic test, a feeding experiment, and a biomarker assay. D. magna were exposed to aqueous solutions of PFNA and PFOS(alone and in combination) at concentrations ranging from 0.008 to 5 mg/L. The survival, growth, and reproduction of D. magna were monitored over a 21-day life cycle. The biomarkers, including acetylcholinesterase(ACh E), superoxide dismutase(SOD), and catalase(CAT) activities, were determined after seven days of exposure. PFOS was more toxic than PFNA based on the results of the acute toxicity test. Perfluorinated compounds(PFCs) inhibited both growth and reproduction of D. magna during the testing period. The ingestion rates and the biomarkers,including ACh E, SOD, and CAT activities, were significantly inhibited by PFCs in most cases. Moreover, the combined effects related to the growth and reproduction showed the antagonistic effects of PFCs.     

Comparative toxicity of nano-scale TiO2, SiO2 and ZnO water suspensions.

TiO2, SiO2 and ZnO are common additives with improved applications at the nanoscale. The antibacterial activity of TiO2, which has important ecosystem health implications, is well understood. However, less attention has been paid to the antibacterial activity of SiO2 and ZnO despite them also producing reactive oxygen species. This paper explores the relative toxicity of TiO2, SiO2 and ZnO water suspensions towards bacteria (B. subtilis, E. coli) and the eukaryotic Daphnia magna. These three photosensitive nanomaterials were hazardous to all test organisms, with toxicity increasing with particle concentration. Toxicity of the three compounds decreased from ZnO to TiO2 to SiO2 and Daphnia were most susceptible to their effects. Nominal particle size did not affect the toxicity of these compounds. Antibacterial activity was noted under both dark and light conditions indicating that mechanisms additional to ROS production were responsible for growth inhibition. These results highlight the need for caution during the use and disposal of such manufactured nanomaterials to prevent unintended environmental impacts, as well as the importance of further research on the mechanisms and factors that increase toxicity to enhance risk management.     

Assessment of sediment quality and pore water ecotoxicity in Kebir Rhumel basin (NE-Algeria): a combined approach

The objectives of this study are to use different approaches to assess the current pollution status in the wadis of the Kebir Rhumel basin. First, sediment trace metal contents were measured by flame atomic absorption spectroscopy. Then, sediment quality was assessed on the basis of contamination assessment indexes such as: Geoaccumulation Index (Igeo), Contamination factor (C(f)), Contamination degree (C(d)), Sediment Pollution Index (SPI) and SEQ guidelines (Consensus Sediment Quality Guidelines). In addition, several toxicity tests (Daphnia magna mobility inhibition acute test-48 h, Aliivibrio fischeri luminescence inhibition acute test - 15/30 mn and Pseudokirchneriella subcapitata growth inhibition chronic test - 72 h) were conducted to assess sediment pore water ecotoxicity. Trace metal concentrations followed the order: Mn > Zn > Pb > Cr > Cu > Ni > Co > Cd. Indexes used indicate varying degrees of sediment quality. Igeo, C(f), C(d) and SPI reveal a polymetallic contamination dominated by two or more elements in which Cd, Cu and Pb are of greatest concern. SEQ guidelines showed that biological effects on fauna would likely be observed occasionally and/or frequently for Cd, Cr, Cu, Pb and Zn contents. Test organisms exposed to sediment pore water showed that the algal P. subcapitata test was more sensitive than the D. magna and A. fischeri tests. Hence, algal growth inhibition proved to be the most sensitive response to contaminants present in sediment extracts but a significant relationship with trace metal contents was not demonstrated.