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Hundreds of chemical contaminants have been identified in the Great Lakes System of North America. Depending on the agency or organization, various subset lists of these contaminants have been identified as chemicals of potential concern. However, there is no agreement on the method that should be used to make management decisions. Except for consensus on approximately 40 chemicals that most North American agencies agree can cause deleterious effects if released into the environment, no agreement has been reached regarding the priority that contaminants should receive for further action. That leaves hundreds of chemicals that have been, are being, or potentially could be released into the environment that have not been evaluated yet. A profile for potential chemicals of concern is generally thought to include persistence in the environment, potential to bioaccumulate, and ability to cause toxic effects at environmentally relevant concentrations. Except for the International Joint Commission’s definition of persistence (> 8 weeks residence time in air, water, soil or sediment), there is little concurrence about what defines these characteristics. For instance, the State of Michigan currently has no established definitions or profiles of persistent, bioaccumulative, toxic substances. Furthermore, there is no standard process to rank chemicals relative to these characteristics. The Chemical Scoring and Ranking Assessment Model (SCRAM) has been developed to provide a process to rank-order chemicals based on these characteristics. The SCRAM system was developed primarily for use in the Great Lakes region of North America and particularly in Michigan, but it is not site-specific. Use of this system may assist in pollution prevention activities and other future chemical control efforts, allowing attention to be focused first on those chemicals likely to present the greatest hazard.  相似文献   

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Japan Atomic Energy Research Institute has developed an emergency response system WSPEEDI to forecast long-range atmospheric dispersions of radionuclides discharged into the atmosphere. The latest version of WSPEEDI consists of an atmospheric dynamic model MM5 for calculating meteorological fields and a particle random-walk model for atmospheric dispersion. The performance of WSPEEDI was evaluated by data obtained from a field tracer experiment over Europe (ETEX) in this paper. The model validation was done with respect to the following points: (1) the dependence of model accuracy on the temporal and spatial resolutions of the meteorological fields and (2) the superiority of an atmospheric dynamic model over a mass-consistent wind model. Regarding (1), it was shown that the calculation accuracy of the new version with high temporal resolution was improved, especially at the edge of the plume. Moreover, although the increase in horizontal spatial resolution of the old version had no substantial effect on the model performance, increase in horizontal resolution of the new version contributed to the significant improvement of the calculation accuracy. These results showed that the dynamically calculated meteorological field with the spatial resolution of the meso-βγ scale greatly improved calculation accuracy.  相似文献   

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Environmental Science and Pollution Research - The use of biocontrol agents (BCAs) is growing across the world and in Europe in particular, where novel ways of farming are highly encouraged and...  相似文献   

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Lutz I  Jie Z  Opitz R  Kloas W  Ying X  Menzel R  Steinberg CE 《Chemosphere》2005,61(8):1183-1188
According to outdated paradigms humic substances (HS) are considered to be refractory or inert that do not directly interact with aquatic organisms. However, they are taken up and induce biotransformation activities and may act as hormone-like substances. In the present study, we tested whether HS can interfere with endocrine regulation in the amphibian Xenopus laevis. In order to exclude contamination with phyto-hormones, which may occur in environmental isolates, the artificial HS1500 was applied. The in vivo results showed that HS1500 causes significant estrogenic effects on X. laevis during its larval development and results of semi-quantitative RT-PCR revealed a marked increase of the estrogenic biomarker estrogen receptor mRNA (ER-mRNA). Furthermore, preliminary RT-PCR results showed that the thyroid-stimulating hormone (TSHbeta-mRNA) is enhanced after exposure to HS1500, indicating a weak adverse effect on T3/T4 availability. Hence, HS may have estrogenic and anti-thyroidal effects on aquatic animals, and therefore may influence the structure of aquatic communities and they may be considered environmental signaling chemicals.  相似文献   

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The potential soil phytotoxicity in the surroundings of an old zinc smelter closed in 1966, was evaluated by a biological test system. This system is based on the analysis of shoot growth and (iso-) enzymes in leaves and roots of 2-week-old seedlings of Phaseolus vulgaris grown on soil samples under controlled environmental conditions. The biological data were presented in a phytotoxicity index, which allowed classification of the soil samples into four phytotoxicity classes. Comparison was made between the biological results and soil and plant metal content. The study revealed that more than 20 years after closure of the factory, the soils in its surroundings were still potentially phytotoxic. Zinc proved to be the most important, but not the only, phytotoxic element, as was shown by isozyme analysis and by the strong correlation between the biological data, the water soluble Zn fraction of the soil and leaf Zn content. The effect of contamination extended to a distance of more than 3 km from the industrial site in the direction of the prevailing wind.  相似文献   

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欧盟是一个由各成员国合作实施共同但又有差别化环境政策的区域,其重金属污染防治工作特色明显。总结分析了欧盟重金属污染防治的管理制度和相关经验,重点研究欧盟在水环境、大气环境、土壤环境以及固体废弃物等领域的重金属污染防治法律法规、标准体系,总结其经验,以期为中国重金属污染防治工作提供参考和借鉴。  相似文献   

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Although modeling of gaseous emissions from motor vehicles is now quite advanced, prediction of particulate emissions is still at an unsophisticated stage. Emission factors for gasoline vehicles are not reliably available, since gasoline vehicles are not included in the European Union (EU) emission test procedure. Regarding diesel vehicles, emission factors are available for different driving cycles but give little information about change of emissions with speed or engine load. We have developed size-specific speed-dependent emission factors for gasoline and diesel vehicles. Other vehicle-generated emission factors are also considered and the empirical equation for re-entrained road dust is modified to include humidity effects. A methodology is proposed to calculate modal (accelerating, cruising, or idling) emission factors. The emission factors cover particle size ranges up to 10 microns, either from published data or from user-defined size distributions. A particulate matter emission factor model (PMFAC), which incorporates virtually all the available information on particulate emissions for European motor vehicles, has been developed. PMFAC calculates the emission factors for five particle size ranges [i.e., total suspended particulates (TSP), PM10, PM5, PM2.5, and PM1] from both vehicle exhaust and nonexhaust emissions, such as tire wear, brake wear, and re-entrained road dust. The model can be used for an unlimited number of roads and lanes, and to calculate emission factors near an intersection in user-defined elements of the lane. PMFAC can be used for a variety of fleet structures. Hot emission factors at the user-defined speed can be calculated for individual vehicles, along with relative cold-to-hot emission factors. The model accounts for the proportions of distance driven with cold engines as a function of ambient temperature and road type (i.e., urban, rural, or motorway). A preliminary evaluation of PMFAC with an available dispersion model to predict the airborne concentration in the urban environment is presented. The trial was on the A6 trunk road where it passes through Loughborough, a medium-size town in the English East Midlands. This evaluation for TSP and PM10 was carried out for a range of traffic fleet compositions, speeds, and meteorological conditions. Given the limited basis of the evaluation, encouraging agreement was shown between predicted and measured concentrations.  相似文献   

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We demonstrate the use of an aldehyde scrubber system to resolve isobaric aldehyde/alkene interferences in a proton transfer reaction mass spectrometer (PTR-MS) by selectively removing the aldehydes from the gas mixture without loss of quantitative information for the alkene components. The aldehyde scrubber system uses a bisulfite solution, which scrubs carbonyl compounds from the gas stream by forming water-soluble carbonyl bisulfite addition products, and has been evaluated using a synthetic mixture of acrolein and isoprene. Trapping efficiencies of acrolein exceeded 97%, whereas the transmission efficiency of isoprene was better than 92%. Quantification of the PTR-MS response to acrolein was validated through an intercomparison study that included two derivatization methods, dinitrophenylhydrazine (DNPH) and O-(4-cyano-2-ethoxybenzyl)hydroxylamine (CNET), and a spectroscopic method using a quantum cascade laser infrared absorption spectroscopy (QCL) instrument. Finally, using cigarette smoke as a complex matrix, the acrolein content was assessed using the scrubber and compared with direct QCL-based detection.  相似文献   

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Selecting chemical substances for the UN-ECE POP protocol   总被引:13,自引:0,他引:13  
In 1998 the UN-ECE POP Protocol was signed. Sixteen substances are included in the protocol. They can be characterised as persistent, bioaccumulating and toxic organic substances prone to long-range atmospheric transport. The Dutch Ministry of Housing, Physical Planning and the Environment started a project to select possible candidates for the protocol. In the first phase of the project possible candidates were selected using the so-called 'PTB-database' applying the criteria from the protocol. From the 12 substances that met the criteria four substances were selected for which preliminary risk profiles were drafted: polychlorinated naphthalenes, dicofol, hexachlorobutadiene and pentachlorobenzene. These profiles are presented. Revised profiles have to be prepared for the UN-ECE LRTAP Ad hoc Expert Group on persistent organic pollutants (POPs). Ultimately, the process should lead to a proposal to include additional POPs to the UN-ECE POP Protocol.  相似文献   

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Gawlik BM  Kettrup A  Muntau H 《Chemosphere》2000,41(9):1337-1347
The European reference soil set was introduced as common basis for a better comparability of soil sorption data measured within the framework of chemical testing of environmental chemicals. The success of the EUROSOILS, as the set is commonly called, convinced the European Commission's Joint Research Centre to evaluate the possibility of producing a remake of these unique and new type of reference materials maintaining the principal sorption-controlling properties of the soils. In this paper the recently proposed second generation of the EUROSOILS is used to evaluate a HPLC-screening technique for the estimation of soil adsorption coefficients of organic chemicals. It could be shown that the derived correlations between HPLC capacity factors of the test substances and the respective soil adsorption coefficients resulting from batch experiments with the second version of the EUROSOILS agreed with those derived for the first generation of reference soils at a different occasion.  相似文献   

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Environmental Science and Pollution Research - The provision of effective sanitation strategies has a significant impact on public health. However, the treatment of septic sludge still presents...  相似文献   

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Müller A  Schulz W  Ruck WK  Weber WH 《Chemosphere》2011,85(8):1211-1219
Non-target screening via high performance liquid chromatography-mass spectrometry (HPLC-MS) has gained increasingly in importance for monitoring organic trace substances in water resources targeted for the production of drinking water. In this article a new approach for evaluating the data from non-target HPLC-MS screening in water is introduced and its advantages are demonstrated using the supply of drinking water as an example. The crucial difference between this and other approaches is the comparison of samples based on compounds (features) determined by their full scan data. In so doing, we take advantage of the temporal, spatial, or process-based relationships among the samples by applying the set operators, UNION, INTERSECT, and COMPLEMENT to the features of each sample. This approach regards all compounds, detectable by the used analytical method. That is the fundamental meaning of non-target screening, which includes all analytical information from the applied technique for further data evaluation. In the given example, in just one step, all detected features (1729) of a landfill leachate sample could be examined for their relevant influences on water purification respectively drinking water. This study shows that 1721 out of 1729 features were not relevant for the water purification. Only eight features could be determined in the untreated water and three of them were found in the final drinking water after ozonation. In so doing, it was possible to identify 1-adamantylamine as contamination of the landfill in the drinking water at a concentration in the range of 20 ng L−1. To support the identification of relevant compounds and their transformation products, the DAIOS database (Database-Assisted Identification of Organic Substances) was used. This database concept includes some functions such as product ion search to increase the efficiency of the database query after the screening. To identify related transformation products the database function “transformation tree” was used.  相似文献   

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According to the European legislation, REACH, organic compounds are considered as substances of very high concern (SVHC) if they are persistent, bioaccumulative and toxic (PBT). A substance's long-range transport potential (LRTP) may also pose a risk to remote regions. This is, however, not yet explicitly included. For identification of compounds, which are not PBT according to REACH criteria, but show LRTP, we investigated 22,438 compounds from the Canadian Domestic Substance List (CDSL). The CDSL was searched for organic, neutral compounds. Substance properties were estimated with EPI Suite v4.00. Next, the substance list was edited in two ways: (1) The half-life criterion in air for LRTP as defined in the Stockholm Convention was applied. (2) For all compounds, indicators for persistence and LRTP were calculated with the multimedia model ELPOS v2.2. Applying the half-life criterion, we identified 594 substances, which are prone to LRT but are not PBT (non-PBT-L substances). In contrast, investigations with ELPOS lead to a shorter list of 188 substances, which are non-PBT-L substances. Finally, the list was compared with potential Arctic contaminants identified in previous literature. Our results show that there is a large number of organic chemicals which would not be considered as SVHC since they are not, at the same time, persistent, bioaccumulative and toxic according to REACH criteria. Nevertheless, they show LRTP according to different screening approaches and thus a potential hazard to remote regions.  相似文献   

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初期雨水污染是城市排水系统面源污染的重要来源,调蓄池等减排设施的应用对缓解初期雨水污染效果显著。由于缺乏科学完善的评估体系,相关调蓄设施的运行和评估工作无章可循,问题日益凸显。以上海市苏州河沿线初期雨水减排调蓄池设施为研究对象,建立规范化的评估体系并针对性地提出评估工作的实施程序,旨在解决当前评估体系不健全、指标不合理、方法不科学等问题,提高设施运行效率。  相似文献   

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