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1.
适用于已知毒物和毒性应用剂量测定的经典技术方法,以样品稀释过程中毒性强度改变与浓度改变的等比率跟随性为基础。废水中的毒性物质常以未知和混合为特征,高毒性的样品现状浓度距离方法预试验中最小全致死浓度较远,以已知毒物重铬酸钾毒性为对照,形成5种毒物高层级等强度毒性,通过这些高毒性废水同步等比率稀释后毒性改变的同步性测定试验,证明毒性废水稀释中强度改变与浓度改变的跟随状态具有不确定性。  相似文献   

2.
A novel biomonitoring system using microbial fuel cells   总被引:2,自引:0,他引:2  
A novel biomonitoring system using microbial fuel cells for detecting the inflow of toxic substances into water systems has been developed for the purpose of on-site and on-line monitoring. The characteristics of electric current generation by electrochemically-active bacteria were conveniently monitored using a microbial fuel cell format and a computer-controlled potentiometer. When toxic substances (an organophosphorus compound, Pb, Hg, and PCBs) were added to the microbial fuel cell, rapid decreases in the current were observed. The inhibition ratios caused by inflow of these toxic substances (1 mg l(-1)) were 61%, 46%, 28% and 38%, respectively, when compared to the control, and generally increased in proportion to the addition time and concentration of toxic substances. When real wastewater was applied from a local wastewater treatment plant, more significant current decreases and higher inhibition ratios were observed following the introduction of toxic substances than in the laboratory tests. For example, the inhibition ratio was 76% on addition of a 1 mg l(-1) Cd and 1 mg l(-1) Pb mixture. Application of the microbial fuel cell for pollutant biomonitoring is discussed.  相似文献   

3.
The effects of physicochemical conditions, such as pH, water hardness, flow rates and natural organic substances on the sensitivity of Ceriodaphnia dubia to the toxic effects of copper were investigated using static bioassay cups and specially designed flow-through bioassay chambers. We found that C.dubia was very sensitive to pH changes and the total copper LC50 values of C. dubia neonates increased by 15-fold as the pH increased from pH 7 to 10. It was also observed that the LC50 values increased sharply upon increasing the water hardness value to 2.4 meq. In addition, increasing flow rates from zeroto 50 mL hr-1 also increased its sensitivity to copper, which was possibly due to hydrodynamic stress.The presence of natural organic substances (humic acid and dissolved organic matter) and suspended particles decreased thetoxic effect of copper. This significant decrease in the toxicity of copper in the presence of natural organic materialscan be explained by a reduction in the free ion concentration due to complexation. Furthermore, we observed that the kinetics of copper interactions with natural organic materials are a significant factor in the toxic effect of copper and that the acute LC50 values increased with increasing reaction time betweensolubilized copper and water-borne organics.  相似文献   

4.
A pot culture experiment was conducted to evaluate the effect of different treatments of distillery wastewater, i.e. raw, treated, diluted and raw distillery wastewater mixed with domestic waste stabilization pond effluent (1:1) on populations of bacteria, fungi, actinomycetes and nitrogen fixing bacteria. The results indicated that raw wastewater decreased the population of bacteria, fungi and actinomycetes. The growth rates of Rhizobium and Azotobacter were also reduced after raw wastewater application. The toxic effect of raw wastewater was minimized when it was mixed with stabilization pond effluent (1:1), this was demonstrated by an increase in the populations of all the microorganisms studied. When a groundnut plant was irrigated with raw distillery wastewater, no fruits were produced and there was also less nodulation. This study indicates that raw distillery wastewater is very toxic to the soil microorganisms which are important in the soil ecosystem.  相似文献   

5.
焦化废水中的溶解性有机物(DOM)作为废水污染物和毒性的主要来源受到广泛关注。厌氧-缺氧-好氧(A-A-O)生物法联合混凝沉淀工艺在焦化废水处理中被广泛应用。于2018年4,7和11月分别采集4座焦化废水处理厂废水,采用光谱学分析手段和水生生物急性毒性试验对A-A-O联合混凝沉淀处理过程中焦化废水的DOM和毒性变化进行分析。结果表明,焦化废水中含有大量不饱和芳香性物质,其中类色氨酸、络氨酸物质占主导,其次为类溶解性微生物代谢产物、类富里酸物质和类腐殖酸类物质;未经处理的焦化废水对藻类和大型溞的急性毒性等级为中毒至高毒。A-A-O联合混凝沉淀处理可去除90%以上的类色氨酸、络氨酸和类富里酸物质,但对类腐殖酸类物质去除率相对较低,仅为约80%,关键去除段为缺氧段和好氧段;该工艺对焦化废水急性毒性削减率为80.51%~94.30%,关键削减段为厌氧段。Pearson相关性分析结果显示,焦化废水溶解性总有机碳(TOC)、类腐殖酸类物质荧光组分C1和类富里酸类物质荧光组分C4与废水急性毒性存在显著正相关关系,可利用其作为水样急性毒性初筛的指示性指标。可为焦化废水生化处理的效能优化和废水毒性控制及安全评估提供科学支撑。  相似文献   

6.
建立了采用液相色谱-串联质谱法(LC-MS/MS)同时测定污水中10种精神活性物质的分析方法。污水样品经甲酸与甲酸铵调节pH后,加入氘代内标混匀,离心并过滤膜后可直接上样分析。研究表明,在1~250 ng/L的线性范围内,10种精神活性物质的线性相关系数均大于0.992,定量限均低于0.5 ng/L。在3个加标水平下,10种精神活性物质的加标回收率为87.2%~114%,相对标准偏差为0.53%~3.60%(n=3)。将该方法应用于某区域10份生活污水样品的检测,在3份水样中检出吗啡、甲基苯丙胺、氯胺酮等精神活性物质,对应的质量浓度范围分别为3.41~9.55、0.90~1.63、1.06~1.78 ng/L。与经固相萃取前处理后的分析方法相比,该方法可在10 min内完成分离和检测的全过程,具有简单、快速、节约的优点,可用于污水样品中10种痕量水平精神活性物质的定量分析。  相似文献   

7.
环境生态风险评估(ERA)流程已经被纳入全球环境政策中,既用于规范新化学物质的授权和营销(前瞻性环境生态风险评估),也用于评估潜在的污染场地(回顾性环境生态风险评估)。将土壤生态毒理学应用于风险评估,能阐明有毒物质对土壤生态系统中生命有机体的危害程度与范围。笔者主要介绍了应用评估因子法和物种敏感度分布法对基于效应数据进行的外推与估算,并综述了欧美等主要国家和地区的土壤生态风险评估框架、相关法律法规及其实施情况等,为中国开展土壤污染物生态毒理效应和风险评估等相关研究提供参考。  相似文献   

8.
为了准确评估厌氧-缺氧-好氧(A2/O)处理工艺对废水毒性的削减效率,采用斑马鱼胚胎急性毒性实验、发光细菌急性毒性实验和小鼠L929细胞毒性实验进行测试,结合理化指标,通过毒性当量(TU)法、平均毒性(AvTx)法、毒性指数(TxPr)法、最敏感测试(MST)法和潜在生态毒性效应(PEEP)法对常州市6家污水处理厂(生活污水、综合废水、化工废水、制药废水)进水和出水的生物毒性进行了评价。结果表明,斑马鱼胚胎的毒性敏感程度最高,3种受试生物的毒性评价结果具有较好的一致性。理化达标的污水处理厂出水仍存在一定的生物毒性效应,出水毒性较大的是综合污水处理厂,排入受纳水体后可能会对周围的生态环境产生潜在的生态风险。A2/O处理工艺对各污水处理厂进水的毒性削减较好,其中对制药废水的毒性削减最高,AvTx、TxPr、MST和PEEP的毒性削减率分别为99.45%、99.64%、99.48%和69.66%。与AvTx、TxPr、MST法相比,PEEP法能够更综合地评价废水毒性。  相似文献   

9.
Lead, one of the earliest metals recognized and used by humans, has a long history of beneficial use. However, it is now recognized as toxic and as posing a widespread threat to humans and wildlife. Treatment of lead from polluted water and wastewater has received a great deal of attention. Adsorption is one of the most common technologies for the treatment of lead-polluted water. This technique was evaluated here, with the goal of identifying innovative, low-cost adsorbent. This study presents experiments undertaken to determine the suitable conditions for the use of peach and apricot stones, produced from food industries as solid waste, as adsorbents for the removal of lead from aqueous solution. Chemical stability of adsorbents, effect of pH, adsorbents dose, adsorption time and equilibrium concentration were studied. The results reveal that adsorption of lead ions onto peach stone was stronger than onto apricot stone up to 3.36% at 3 h adsorption time. Suitable equilibrium time for the adsorption was 3–5 h (% Pb adsorption 93% for apricot and 97.64% for peach). The effective adsorption range for pH in the range was 7–8. Application of Langmuir and Freundlich isotherm models show high adsorption maximum and binding energies for using these adsorbents for the removal of lead ions from contaminated water and wastewater.  相似文献   

10.
A multi-component screening analysis method for polar to medium-polar water pollutants was developed. Sample clean-up and group separation are performed by sequential solid-phase extraction (SSPE) using automated SPE with C18 and polymeric sorbent materials. Analyses are performed by liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) using a single-quadrupole instrument. More than 90 priority compounds of environmental interest--comprising the most important chemical and substance classes: phenols, carboxylic acids, aromatic sulfonates, aromatic amines, pharmaceuticals, surfactants, dyes, and pesticides--have been chosen for the experiments. The compounds are divided by the SSPE procedure into 3 different polarity classes. The extraction recoveries were determined in the 3 fractions for every single substance, and were for most of the analytes in the range of 50-100%. A mixture of hexane-dichloromethane was used for the elution of nonpolar compounds like alkylphenols from C18. Methanol and acetone are well suited for the elution of more polar substances. The limits of detection (LODs) were determined for all compounds. Effluents from municipal and industrial wastewater treatment plants (WWTPs) treating waste water from textile industries; and the corresponding receiving waters (rivers and lakes) have been analysed with the developed method. Urban and industrial pollution was observed in rivers and streams in the area north of Milan, Italy. In the water samples different phenols (nitrophenols, bisphenol A, nonylphenol), alkylphenol ethoxylate surfactants, their metabolites with endocrine disrupting potential, aromatic sulfonates, linear alkylbenzenesulfonate surfactants, dyes, pesticides, pharmaceuticals, and a dichlorobenzidine compound were identified.  相似文献   

11.
气相分子吸收光谱法测定成分复杂氨氮实际样品时,干扰因素造成测定结果不准确,而现有的标准方法和文献对干扰物质的研究不全面,制约了仪器的应用。该文系统地开展干扰因素的研究,提出干扰因素的消除方法,用加标回收率验证消除的有效性。结果表明,亚硫酸盐、硫化物等还原性物质对测定产生负干扰;石油烃、N,N-二甲基甲酰胺(DMF)等挥发性有机物、有机胺类以及亚硝酸盐对测定产生正干扰。根据不同干扰类型,通过加入适量酸性重铬酸钾溶液、在酸性条件下加热煮沸、预蒸馏等方法可消除干扰,消除干扰后加标回收率为84%~120%。生活污水、石化企业废水等6种典型水样消除干扰后,气相分子吸收光谱法和纳氏试剂分光光度法测定氨氮有较好的可比性,干扰消除方式有效。  相似文献   

12.
气相色谱法测定苯酚生产废水中芳香族化合物   总被引:1,自引:1,他引:0  
建立了用气相色谱法同时测定苯酚生产废水中异丙苯、α-甲基苯乙烯、α-甲基苯甲醇、2-苯基-2-丙醇、苯酚、苯乙酮、2-苯基丙醛等7种芳香族有毒有机污染物的定量分析方法。采用二氯甲烷对水样进行萃取后进行分析测定,气相色谱条件:DB-WAX型色谱柱,FID检测器,程序升温,进样量1μL。方法的检出限、精密度、回收率实验表明,该方法对苯酚生产废水中各污染物组分具有较好的分离效果,对7种物质的检测限均低于0.05 mg/L,5次测定的相对标准偏差小于5%,实际水样的加标回收率大于97%。  相似文献   

13.
对水中14种酚类化合物的衍生化过程进行研究,选取不同衍生化试剂、衍生温度和衍生时间、最大衍生量等多个对衍生效率有决定性影响的参数进行优化。通过上述条件的优化选择,实现了对苯酚、氯代酚、甲基酚和硝基酚等14种不同类型酚类化合物最优的衍生化,衍生效率达到75.5%~119%。  相似文献   

14.
A simple and sensitive method was developed for determination of trace copper by direct precipitation preconcentration and detection with Flame Atomic Absorption Spectrometry (FAAS). The reagent 2-[2'-(6-methyl-benzothiazolylazo)]-4-aminophenol (Me-BTAP) was used as precipitating agent. The experimental conditions for the quantitative precipitation of copper, such as pH, amount of reagents, temperature and the effect of diverse ions on the precipitation have been investigated. It was found that copper is quantitatively extracted (> or =95%) and the method provides a sensitivity enhancement of 40-fold for a 10 ml sample volume with a detection limit of 0.5 microg l(-1). The proposed method was successfully applied for the determination of trace copper in water, urine and biological samples.  相似文献   

15.
重氮偶联法作为测定亚硝酸盐氮的标准方法,因具有方法灵敏、选择性强、仪器较易获得等优点,被实验室广泛采用,但也存在测定上限较低,适用样品范围较窄等缺点。通过将显色剂中磷酸改为盐酸,把重氮试剂含量提高到国标法的3倍,明显提高亚硝酸盐氮的测定上限,即由原国标法上限的0.2 mg/L提高到0.6 mg/L,灵敏度与国标法接近,且准确度和精密度良好,6组标准溶液平行测定的相对误差为1.60%,相对标准偏差为1.34%,加标回收率为96.5%~104.9%,适用于生活污水、工业废水、地表水、养殖废水等水体的测定。  相似文献   

16.
Monitoring of Phenol in Wastewater Bioremediation by HPLC   总被引:1,自引:0,他引:1  
Bioremediation emphasizes the detoxification and destruction of toxic substances by microorganisms. Wastewater obtained from an industrial concern was solvent extracted with methyl alcohol and dichloromethane and analysed by GC/MS. Besides phenol, a large variety of organic compounds were detected. Under controlled laboratory conditions, the wastewater was innoculated with a mixed culture of microorganisms specially selected for their abilities to degrade phenol. Samples were collected at regular intervals from the stirred tank bioreactor and analysed for phenol by reverse phase HPLC with a C18 column. Results shows that from an initial phenol concentration of 987 ppm, slightly more than 50% was destroyed within 163 hours. The dry weight of the microorganisms and the plate count (CFU/ml) shows a steady increase from 0.5238 gms to 0.5355 gms and from 1.1E+9 to 1.94E+13 respectively over the same period. This suggested that the phenol was consumed by the microorganisms as the sole carbon source.  相似文献   

17.
A multi-channel continuous water toxicity monitoring system was, after confirming the systems' performance, implemented to samples of water discharged from power plants to detect and classify their toxicity using several recombinant bioluminescent bacteria. Each channel of the system is composed of a series of two mini-bioreactors to enable a continuous operation, i.e., without system interruption due to highly toxic samples. A different recombinant bacterial strain was present in each channel: DPD2540 (fabA::lux CDABE), DPD2794 (recA::luxCDABE), and TV1061 (grpE::luxCDABE), which are induced by cell membrane-, DNA-, and protein-damaging agents, respectively. GC2 (lac::luxCDABE) is a constitutive strain, whose bioluminescence is reduced by an increase in cellular toxicity. Phenol and mitomycin C (MMC) were used for evaluating the system's performance to detect toxic chemicals. These samples were injected into the second mini-bioreactor according to a step or bell-curve manner. The field samples used in this study were obtained from the water discharged from two different power plants in Korea – from a nuclear power plant and a thermo-electronic power plant, and were injected into the second mini-bioreactor to initiate the toxicity test. Each channel showed specific bioluminescent (BL) response profiles due to the toxic compounds present in the water samples. Comparing the BL signals between the standard toxic chemical samples and discharged water samples, the equivalent toxicity of the field water could be estimated. Finally, it was proved that this novel continuous toxicity monitoring system can be used as an alternative tool for the quick monitoring and control of water quality, as well as aid in the setting up of a new monitoring strategy to protect the source of tap water and in the prevention of polluted water discharge.  相似文献   

18.
The occurrence, concentrations, patterns, and loads of 17 2,3,7,8-substituted congeners of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in treated wastewater collected at the outlets from 14 wastewater treatment plants (WTPs), divided into three size categories. The analysis also considered the effect of wastewater outflow on the final concentrations of PCDDs/Fs, as the samples were collected during flooding and stable hydrological conditions. None of the studied WTPs were found to completely remove toxic congeners of PCDDs/Fs from wastewater: the PCDD concentrations in the outgoing effluent during stable wastewater flow ranged from 2.99 to 177.19 pg/L, PCDFs from 6.05 to 51.30 pg/L, and the Toxic Equivalent (TEQ) was between 0.94 and 4.87 pg/L. The results from high wastewater flow were less diversified, ranging from 5.04 to 8.85 pg/L for PCDDs, from 11.47 to 32.33 pg/L for PCDFs and from 2.00 to 4.65 pg/L for TEQ. The smallest WTPs demonstrated the highest average total and TEQ concentrations due to limited volume, short retention time and outdated technology, and, hence, insufficient treatment efficiency. The largest WTPs have the potential to substantially affect the quality of river water, as despite being associated with the lowest concentrations, they released much greater volumes of treated wastewater and, hence, the greatest amounts of analyzed compounds. Elevated TEQ values were observed at high flow in all WTP size categories indicating the impact of high and stable wastewater flow on the concentrations of the observed PCDDs/Fs.  相似文献   

19.
微回流管封闭回流应用于废水中COD检测的方法研究   总被引:3,自引:0,他引:3  
研究了耐高压的微回流管封闭回流装置来消解废水中有机污染物 ,由试验确定各试剂最佳用量替代 HACH公司进口试剂包 ,建立废水中 COD测定的新方法  相似文献   

20.
Plant-based bioassays have recently gained remarkable popularity among the toxicological/eco-toxicological assessment procedures. The reasons for their wide use are comparative simplicity, sensitivity, and cost-effectiveness as well as a good correlation with other toxicity tests. The present study describes the use of two plant bioassays, Allium cepa test and seed germination test in the evaluation of the toxicity/genotoxicity of industrial waste water and river water and standardization with the commonly occurring pollutants in Indian waters namely heavy metals and phenolics. Both tests were standardized to suit the Indian conditions, and the local varieties were used. Both bioassays responded significantly with the test range of heavy metals and phenolics. The toxicity of heavy metals was in the order of Cu > Ni > Cd in both the tests whereas 2,4-dinitrophenol was the most toxic among the phenolic compounds. Cabbage, millet, and cucumber, respectively, were found to be the most sensitive in the seed germination test for the test heavy metals and phenols. Significant amounts of chromosomal abnormalities including bridges, stickiness, and fragmentations were recorded with both the industrial waste water and the XAD concentrated river water samples by A. cepa test.  相似文献   

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