排序方式: 共有17条查询结果,搜索用时 15 毫秒
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T. Neuparth R. Capela L. Rey-Salgueiro S.M. Moreira M.M. Santos M.A. Reis-Henriques 《Chemosphere》2013
Despite the extensive maritime transportation of Hazardous and Noxious Substances (HNS), there is a current lack of knowledge on the effects posed by HNS spills on the marine biota. Among the HNS identified as priority, acrylonitrile was selected to conduct ecotoxicological assays. We assessed the acute and subletal effects of acrylonitrile in seabass, followed by a recovery phase to simulate the conditions of a spill incident. The work aimed at testing a broad range of biological responses induced by acrylonitrile. Sublethal exposure to the highest two doses increased the fish mortality rate (8.3% and 25% mortality in 0.75 and 2 mg L−1 acrylonitrile concentrations), whereas no mortality were observed in control and 0.15 mg L−1 treatments. Additionally, important alterations at sub-individual level were observed. Acrylonitrile significantly induced the activities of Catalase– CAT and Glutathione S-Transferase – GST; and the levels of DNA damage were significantly increased. Conversely, Superoxide Dismutase– SOD – activity was found to be significantly inhibited and no effects were found on Lipid Peroxidation– LPO and ethoxyresorufin O-deethylase – EROD – activity. Following a 7 d recovery period, the levels of CAT, GST and EROD fell to levels at or below those in the control. In the 2 mg L−1 group, SOD remained at the levels found during exposure phase. This study has gathered essential information on the acute and subletal toxicity of acrylonitrile to seabass. It also demonstrated that 7 d recovery allowed a return of most endpoints to background levels. These data will be useful to assist relevant bodies in preparedness and response to HNS spills. 相似文献
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Dorothy E. Patton 《Journal of environmental science and health. Part. B》2013,48(6):645-663
Abstract The United States Environmental Protection Agency administers several laws and progrms through which it reviews the hazard potential of pesticides and other toxic substances which may present a risk to human health or the environment. The Agency's ability to assess hazard as required by law depends in part on test data developed through testing standards in Agency regulations. In reviewing the Agency's actions in this regard, the courts emphasize the importance of reasoned regulatory decisions. The legal requirements to assess risk and provide reasoned decisions in this regard establish the legal importance of testing guidelines and test data, and indicate that sound test methodology is as important legally as it is scientifically. 相似文献
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采用3种电子受体(硝氮、亚硝氮、氧),在SBR反应器中分别驯化了具有稳定除磷能力的聚磷污泥。对比研究了不同聚磷污泥胞外聚合物(EPS)的组分与含量,结合三维荧光光谱对EPS中有机物质进行分析。研究表明,以硝氮、亚硝氮为电子受体的聚磷污泥EPS平均浓度较为接近,分别为115.6mg/gVSS、133.5 mg/gVSS,由厌氧段至缺氧段,EPS总浓度有所下降。以氧为电子受体聚磷污泥的EPS平均浓度相对较高,为194.5 mg/gVSS,由厌氧段至好氧段,EPS总浓度略有升高。不同聚磷污泥的EPS组分均以胞外蛋白为主,占EPS总量的53%~65%,多糖与核酸占EPS总量28%~34%、5%~7%。三维荧光光谱显示3种聚磷污泥EPS均具有芳香结构蛋白质、可溶性代谢物的荧光峰,另外,以硝氮为电子受体的聚磷污泥还具有明显的腐殖酸类物质的荧光峰。研究结果表明电子受体对聚磷污泥EPS的组分、浓度、有机质类别有一定的影响。 相似文献
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简述了PFASs在长江流域上、中、下游水环境中的空间分布格局和时间变化趋势,探讨了其生物蓄积效应、淡水生物毒性效应和生态风险评价。指出,PFASs广泛赋存于长江流域从上游至下游的干流和支流及湖泊之中,其平均值低于我国其他主要流域;PFOA在长江流域内环境浓度最高,而PFOS在近10年环境管控措施下浓度降至极低,PFBS、PFBA和PFHxA等短链物质正作为替代物使用,可能在未来出现升高趋势。长江流域内水生动物(包括食用鱼类)能够从环境中富集PFASs并通过食物链传输,在其血液、肌肉和内脏中蓄积。虽然目前长江流域生态风险评价表明PFASs总体上风险为低级,但局部高浓度地区仍可能对敏感生物造成基因表达受损等毒性效应。 相似文献
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建立了模拟的SBR反应器,并研究了ZnO纳米颗粒(ZnO-NPs)对SBR活性污泥活性的影响.结果表明低浓度(10mg/L)ZnO-NPs对活性污泥活性无明显抑制作用.较高浓度下,ZnO-NPs对活性污泥沉降性能?呼吸速率?EPS和SMP产量及其组成?有机物降解效率等具有明显影响.20,50,100mg/L ZnO-NPs使COD去除率分别降低8.1%, 19.5%和27.7%,使污泥沉降性能分别降低24.2%,35.0%和36.0%,使MLVSS/MLSS比值分别降低8.0%,14.7%和21%,使活性污泥呼吸速率抑制率达到54.0%, 79.0%和80.3%;使EPS产量分别降低29.0%,49.9%和65.4%,使SMP产量分别升高48.9%,102.6%和203.0%.研究表明,较高浓度ZnO-NPs能够抑制污泥代谢,降低活性污泥生物量,显著抑制活性污泥活性. 相似文献
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Pierre Hennebert Arnaud Papin Jean-Marie Padox Benoît Hasebrouck 《Waste management (New York, N.Y.)》2013,33(7):1577-1588
The classification of waste as hazardous could soon be assessed in Europe using largely the hazard properties of its constituents, according to the the Classification, Labelling and Packaging (CLP) regulation. Comprehensive knowledge of the component constituents of a given waste will therefore be necessary. An analytical protocol for determining waste composition is proposed, which includes using inductively coupled plasma (ICP) screening methods to identify major elements and gas chromatography/mass spectrometry (GC–MS) screening techniques to measure organic compounds. The method includes a gross or indicator measure of ‘pools’ of higher molecular weight organic substances that are taken to be less bioactive and less hazardous, and of unresolved ‘mass’ during the chromatography of volatile and semi-volatile compounds. The concentration of some elements and specific compounds that are linked to specific hazard properties and are subject to specific regulation (examples include: heavy metals, chromium(VI), cyanides, organo-halogens, and PCBs) are determined by classical quantitative analysis. To check the consistency of the analysis, the sum of the concentrations (including unresolved ‘pools’) should give a mass balance between 90% and 110%. Thirty-two laboratory samples comprising different industrial wastes (liquids and solids) were tested by two routine service laboratories, to give circa 7000 parameter results. Despite discrepancies in some parameters, a satisfactory sum of estimated or measured concentrations (analytical balance) of 90% was reached for 20 samples (63% of the overall total) during this first test exercise, with identified reasons for most of the unsatisfactory results. Regular use of this protocol (which is now included in the French legislation) has enabled service laboratories to reach a 90% mass balance for nearly all the solid samples tested, and most of liquid samples (difficulties were caused in some samples from polymers in solution and vegetable oil). The protocol is submitted to French and European normalization bodies (AFNOR and CEN) and further improvements are awaited. 相似文献
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S. U. Khan 《Journal of environmental science and health. Part. B》2013,48(6):1071-1090
Abstract The data presented in this paper emphasize that the behavior and fate of pesticides in the environment is influenced by humic substances. Various methods most frequently used for the characterization of humic substances are discussed. Both humic acid and fulvic acid can solubilize in water certain organic compounds and are important carriers of some pesticides in soil. Humic substances have the potential for promoting the nonbiological degradation of many pesticides. Several methods of bleaching humus color from drinking water, including chlorination, ozonation, and UV‐radiation, are described. Finally, the photochemical stability to UV‐radiation of certain pesticides in aqueous fulvic acid solution is discussed. 相似文献
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在微风或无风条件下,采用沉积物捕获器和Gansith公式对异龙湖水体中颗粒物沉降和再悬浮进行了研究。结果表明:在微风或无风状态下,底泥再悬浮对水体悬浮物含量贡献较大;描述底泥再悬浮的动态过程需要的合适监测时间为48 h。 相似文献