在线生物监测技术用于典型农药突发性污染的研究

水源水突发性污染监测技术是当前的研究重点,导致突发性污染事故的末知污染物可通过暴露于污染的水生生物行为改变来实现在线生物监测.通过48 h暴露,以标准水为对照,研究了经差分滤除以后,大型蚤在一定农药浓度下的相对行为变化,进一步说明生物行为生态学变化在水体生物监测中的指示作用.研究结果表明,在不同浓度百菌清、除草醚和溴氰菊酯的作用下,大型蚤的运动行为强度会发生剧烈变化,并呈现明显的剂量-效应关系.在一定浓度的农药暴露中,暴露生物的行为强度在经历一个短暂的突增后,会随暴露时间增加而逐步减弱.因此,通过监测大型蚤运动相对行为变化,可以实现对百菌清、除草醚和溴氰菊酯农药污染事故的在线生物监测.     

KS2601型智能水质生物毒性在线监测预警系统

<正>一、系统简介KS2601型智能水质生物毒性在线监测预警系统是专门针对国家环境监测部门对水质安全的监控预警需求而研发的新型产品,能够实现对水体综合毒性的实时监测和在线预警。系统以国际标准受试鱼种蓝腮太阳鱼作为监测对象,以蓝腮太阳鱼的行为变     

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。     

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。     

不同营养级生物毒性监测预警比较研究

生物毒性监测作为水质安全评价预警的重要手段,能更直观地反映污染物对生态系统和人类健康的潜在风险,可以和理化监测一并深入反映水质污染现状。为进一步推动生物毒性监测技术发展与应用,研究了4种不同营养级生物(鱼类、溞类、藻类及发光菌)对不同污染物的响应。研究结果表明：(1)斑马鱼对污染物响应范围相对较广,响应阈值相对较高;大型溞对污染物敏感度最强,响应阈值相对较低,响应时间相对较长,预警灵敏度较鱼类好;蛋白核小球藻对污染物响应范围比较窄,对除草剂外的其他污染物敏感性较弱;费氏弧菌对污染物响应比较广谱且迅速,对部分污染物的响应阈值较高。(2)不同指示生物对污染物的响应范围、响应时间及响应阈值均不一,单一指示生物难以全面、高效地预警污染物,需不同级别指示生物联合预警,进而提高监测预警效率。     

福建省不同水期地表水水质变化规律及成因分析

该文统计分析福建省2007-2017年水质监测成果资料,结果表明:福建省地表水水质年际间变化较明显,变化规律一般随年地表水资源量变化而变化;全省各主要河流汛期水质明显好于非汛期水质;不同水期,水质影响因素不是单一性的,而是综合性的。     

大型溞和发光细菌对城市水源地典型污染物敏感性比较研究

以发光细菌和大型潘为测试对象,利用Delta tox毒性检测仪和大型潘急性毒性标准测试方法测定了城市水源地水体中常见典型污染物如抗生素、重金属、农药类药物对发光菌和大型溞的急性毒性的影响。结果显示,所调查的污染物中,恩诺沙星对发光菌的EC50为9.8 mg/L,对大型溞LC50(48 h)为88 mg/L;发光菌对恩诺沙星暴露的敏感性强于大型溞。而磺胺嘧啶、Cr6+、Cd2+、乐果、敌敌畏、马拉硫磷、氯氰菊酯等污染物对大型溞的LC50(48 h)分别为184 mg/L、0.46 mg/L、0.04 mg/L、0.28 mg/L、0.006 mg/L、0.007 rmg/L、0.0006 mg/L,其敏感性高于发光菌EC50(430 mg/L、60 mg/L、11.1 mg/L、24 mg/L、161.1 mg/L、1.27 mmg/L、0.063 mg/L)。研究表明,大型潘对于城市饮用水及水源地水体中常见典型污染物的监测具有较高的敏感性和预警作用。     

固定化微生物处理河流微污染水体试验研究

采用固定化微生物-曝气生物滤池(IBAF)系统对北京市马草河微污染水体进行了现场连续运转中试研究.通过对进水与出水COD、氨氮和总磷的监测,研究了IBAF系统对河湖微污染水体的处理性能.结果显示:采用IBAF系统处理河流微污染水体,处理后主要水质指标可达到地表水Ⅳ类水体标准;各污染物的去除率分别达到:CODcr60%以上、CODMn30%以上、氨氮90%以上和总磷在50%以上;克氏定氮法测定表明IBAF系统中的生物量为35 g/L,可极大地提高处理效率;IBAF系统在驯化完成后,能够满足重复使用的要求;试验还表明在温度5～15℃的条件下,IBAF系统脱除氨氮性能未受影响,这对低温脱氮的研究具有重要的意义.     

浊漳河水质污染分析与治理保护建议

在浊漳河上选取6处水质监测断面,以2010年、2011年的监测数据为依据,阐述浊漳河支流和干流连续2年的水质变化情况,分析污染原因,分段查找,分段治理,保证浊漳河干流水质质量达到《地表水环境质量标准GB3838-2002》中的Ⅲ类标准。浊漳河水质污染主要是支流污染以及沿途污水处理排放标准远远高于地表水Ⅲ类标准,在此基础上,提出浊漳河水质污染治理保护建议。     

螃蟹扰动作用对滨海湿地水盐交换的影响

为探究生物扰动作用对滨海湿地物质交换的影响,以螃蟹为研究对象进行室内控制试验,模拟了潮汐条件下不同螃蟹密度时沉积物地貌变化和水盐运移情况。结果表明:螃蟹能够将大量地下沉积物搬运至地表,形成起伏多变的微地形,使沉积物表面积明显增大;螃蟹活动能促进地表水与地下水交换,加快浅层土壤的盐分运移过程;地表水与地下水交换量和盐分运移量均随螃蟹密度的增大而明显增大。生物扰动作用是造成沉积物地貌改变的重要因素,进而促进了滨海湿地的水盐交换。     

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.     

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.     

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.     

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.     

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.     

Application of the biotic ligand model to predict copper acute toxicity to Medaka fish in typical Chinese rivers

LA50, the Lethal Accumulation of Cu on the Medaka fish (Oryzias latipes) gills that results in 50% mortality during a toxicological exposure (96 hours) in synthetic water was assessed by use of the biotic ligand model (BLM). The LA50 was employed to predict the 96 h Cu toxicity (LC50) to this fish in different natural surface waters in China. The LC50 values were predicted with errors of no more than 1.55 for the river water except for two water samples, one of which was from a tidal river and the other of which was from a river that was subject to joint metal pollution and possibly affected by other pollutants.     

Parathion degradation and toxicity reduction in solar photocatalysis and photolysis.

The solar photocatalytic degradation of methyl parathion was investigated using a circulating TiO2/solar light reactor. Under solar photocatalysis condition, parathion was more effectively degraded than solar photolysis and TiO2-only conditions. With solar photocatalysis, 20 mg/L of parathion was completely degraded within 60 min with a TOC decrease of 63% after 150 min. The main ionic byproducts during photocatalysis recovered from parathion degradation were mainly as NO3-, NO2- and NH4+, 80% of the sulphur as SO4(2-), and 5% of phosphorus as PO4(3-). The organic intermediates 4-nitrophenol and methyl paraoxon were also identified, and these were further degraded in solar photocatalytic condition. Two different bioassays (Vibrio fischeri and Daphnia magna) were used to test the acute toxicity of solutions treated by solar photocatalysis and photolysis. The Microtox test using V. fischeri showed that the toxicity expressed as EC50 (%) value increased from 5.5% to >82% in solar photocatalysis, indicating that the treated solution is non-toxic, but only increased from 4.9 to 20.5% after 150 min in solar photolysis. The acute toxicity test using D. magna showed that EC50 (%) increased from 0.05 to 1.08% under solar photocatalysis, but only increased to 0.12% after 150 min with solar photolysis, indicating the solution is still toxic. The pattern of toxicity reduction parallels the decrease in TOC and the parathion concentrations.