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171.
INTRODUCTION: Endocrine disrupting chemicals (EDCs) are present in the environment and can have serious effects on humans and wildlife. For the establishment of environmental quality guidelines and regulation of EDCs, a better understanding and knowledge of the occurrence and the behavior of environmental EDCs is necessary. The aim of the present study was to comprehensively identify substances that are responsible for the estrogenic effect of an environmental sediment sample taken from the river Elbe/Germany. DISCUSSION: The estrogenic effect of the organic sediment extract was determined using the yeast-estrogen-screen (YES). The sample was fractionated by liquid chromatography (LC) for effect directed analysis. The composition of estrogen-active fractions was further investigated by gas chromatography-mass spectrometry and high-resolution LC-MS analysis. The composition of the environmental sample was rebuilt with pure compounds in order to assess the partition of estrogenic activity caused by the identified compounds. The organic sediment extract showed an estrogenic potential of 1.9?±?0.4 ng/g ethinylestradiol equivalents in the sediment. The most prominent contaminants with an estrogenic potential were 17β-estradiol, estrone, and 4-iso-nonylphenols, but other xenoestrogens like bisphenol A and stigmasterol could be found as well. A rebuild of the sample was measured in the YES in order to investigate mixture effects. About 67 % of the observed estrogenic effect in the sediment extract could be explained by a mixture which contained all identified compounds. Chlorophene (o-benzyl-p-chlorophenol)-a widely used antiseptic that was also identified in the sediment extract-has xenoestrogenic properties in the YES that are in the range of other xenoestrogens like 4-n-nonylphenol. This is the first report on chlorophene acting as a xenoestrogen.  相似文献   
172.
Sustainability as an increasingly popular theme in Contemporary Public Art. The three pillar model of sustainability is used to examine works that deal specifically with the topic of economic, social and environmental sustainability. Viewing these contemporary art works through the lens of sustainability gives new meaning and significance to what many of these contemporary artist are trying to achieve.  相似文献   
173.
End-of-life vehicles (ELV) have become a global concern as automobiles have become popular worldwide. An international workshop was held to gather data and to discuss 3R policies and ELV recycling systems, their background and present situation, outcomes of related policies and programs, the framework of recycling and waste management, and case studies on related topics in several countries and regions, as well as the essential points of the comparison. Legislative ELV recycling systems are established in the EU, Japan, Korea, and China, while in the US, ELV recycling is managed under existing laws on environmental protection. Since automobile shredding residue (ASR) has a high calorific value and ash content, and includes heavy metals as well as a mass of unclassified fine particles, recycling ASR is considered highly difficult. Countries with a legislative ELV system commonly set a target for recovery rates, with many aiming for more than 95 % recovery. In order to reach this target, higher efficiency in ASR recovery is needed, in addition to material recycling of collectable components and metals. Environmentally friendly design was considered necessary at the planning and manufacturing stages, and the development of recycling systems and techniques in line with these changes are required for sound ELV management.  相似文献   
174.
Concentrations of nine heavy metals (As, Cd, Cu, Fe, Hg, Pb, Mn, Mo and Zn) were determined in the hepatic and renal tissues of 80 stranded California sea lions (Zalophus californianus). Significant age-dependant increases were observed in liver and kidney concentrations of cadmium and mercury, and renal zinc concentrations. Hepatic iron concentrations were significantly higher in females than males. Animals with suspected domoic acid associated pathological findings had significantly higher concentrations of liver and kidney cadmium; and significantly higher liver mercury concentrations when compared to animals classified with infectious disease or traumatic mortality. Significantly higher hepatic burdens of molybdenum and zinc were found in animals that died from infectious diseases. This is the largest study of tissue heavy metal concentrations in California sea lions to date. These data demonstrate how passive monitoring of stranded animals can provide insight into environmental impacts on marine mammals.  相似文献   
175.
Developing regulatory activities (e.g., REACh, [DGEE. 2003. Directorates General Enterprise and Environment. The new EU chemicals legislation REACH. DG Enterprise, Brussels, Belgium. (http://www.europa.eu.int/comm/enterprise/reach/index_en.htm)]) will require bioaccumulation to be assessed for thousands of chemicals. Further, there is increasing pressure to reduce, refine or replace animal tests. Given this scenario, there is an urgent need to evaluate the feasibility of in vitro systems to supply data useful for bioaccumulation estimation. Subcellular and cellular hepatic systems were tested to determine the biotransformation of two surfactants: C12-2-LAS (2-phenyl dodecane p-sulfonate) and an alcohol ethoxylate C13EO8 (Octaethylene glycol monotridecyl ether). The subcellular systems tested were liver homogenates and microsomes from the common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss). Cellular systems consisted of primary hepatocytes from the common carp (Cyprinus carpio) and PLHC-1 cells, hepatocarcinoma cells from the desert topminnow (Poeciliopsis lucida). All in vitro systems were exposed to radiolabeled test compounds and assayed for biotransformation using liquid scintillation and thin layer chromatographic methods. First-order kinetics were used to estimate rates of biotransformation. Bioconcentration of test materials in fish were predicted using an in vitro to in vivo metabolic rate extrapolation model linked to a mass-balance model commonly used to predict bioaccumulation in fish. Subcellular biotransformation rates for each of the surfactants were greatest with microsomes. Cellular loss rates exceeded subcellular rates, leading to lower predicted BCF values. Predicted BCFs corresponded closely to measured values in several fish species, verifying the utility of in vitro systems in refining Kow-only-based BCFs via the inclusion of biotransformation rates.  相似文献   
176.
Environmental Science and Pollution Research - Benzimidazoles are anthelmintics frequently used in sheep farming due to the high susceptibility of these animals to parasitic diseases. Sheep excreta...  相似文献   
177.

This paper discusses the use of Material Flow Analysis (MFA) as a tool to support policy decision making in the field of resource and environmental management. In terms of policy, MFA can be used for early recognition, priority setting, to analyse and improve the effectiveness of measures and to design efficient material management strategies in view of sustainability. MFA has a high potential to be implemented as a guiding tool at the regional level, for example as part of a regional environmental management and audit system or as a part of the Local Agenda 21 process. Material management based on MFA is complementary to traditional environmental and resource management strategies, which have tended to focus heavily on specific environmental compartments, and measure the concentration of substances in various media. MFA, in contrast, provides an overview of the total system by linking the anthroposphere (that part of the biosphere in which humans' activities take place) with the environment. This system approach shifts the focus away from the back-end so-called 'filter strategies' to more pro-active front-end measures. MFA examines short- and long-term loadings rather than concentrations and highlights current and potential material accumulations, called material stocks. These stocks represent either potential environmental problems (e.g. large stocks of hazardous materials) or a potential source of future resources (e.g. urban mining). In this way, MFA can assist precautionary policy making by highlighting future environmental or resource issue problems without relying on signals of environmental stress. The objective of materials management is: firstly, to analyse material flows and stocks; secondly, to evaluate these results; and thirdly, to control material flows in view of certain goals such as sustainable development. MFA is an excellent tool for the first objective and is well suited to generate a base for the other two objectives. MFA results can be compared against environmental standards or can be interpreted using assessment or indicator methodologies (such as environmental impact assessment or ecological footprints). Selected results from two studies, carried out for the city of Vienna (substance management) and the Swiss lowlands (timber management), illustrate the use of MFA as a tool for early recognition (resource depletion and environmental quality), for priority setting and for effective policy making.  相似文献   
178.
179.
We observed a pronounced, yet reversible tissue reduction in the tropical sponge Aplysinella sp. under non-experimental conditions in its natural habitat, after transfer into seawater tanks, as well as after transplantation from deep to shallow water in the field. Tissue reduction resulted in the formation of small “reduction bodies” tightly attached to the sponge skeleton. Although volume loss and gain were substantial, both tissue reduction and regeneration were often remarkably rapid, occurring within few hours. Microscopic analysis of the reduction bodies revealed morphological similarities to previously described sponge primmorphs, with densely packed archaeocytes and spherulous cells enclosed by a thin layer of epithelial-like cells. Denaturing gradient gel electrophoresis (DGGE) revealed pronounced changes in the sponge-associated microbial community upon tissue reduction during laboratory and field experiments and following changes in ambient conditions after transplantation in the field. Generally, the microbial community associated with this sponge proved less stable, less abundant, and less diverse than those of other, previously investigated Verongid sponges. However, one single phylotype was consistently present in DGGE profiles of Aplysinella sp. This phylotype clustered with γ-proteobacterial sequences found previously in other sponge species of different taxonomic affiliations and geographic provenances, as well as in sponge larvae. No apparent changes in the total secondary metabolite content (per dry weight) occurred in Aplysinella sp. upon tissue reduction; however, comparative analysis of intact and reduced tissue suggested changes in the concentrations of two minor compounds. Besides being ecologically interesting, the tissue reduction phenomenon in Aplysinella sp. provides an experimentally manipulable system for studies on sponge/microbe symbioses. Moreover, it may prove useful as a model system to investigate molecular mechanisms of basic Metazoan traits in vivo, complementing the in vitro sponge primmorph system currently used in this context.  相似文献   
180.

Background

The water protection policy of the European Union sits on new footings since the end of 2000: The Water FrameworkDirective (WFD). By replacing, merging and renewing all parts of the European water protection policy from the 1970s, the WFD provides a consistent, transparent and comprehensive concept of what water management should be in the Europe of the coming decades. The new directive is aimed at a holistic approach towards integrated water protection. It sets ambitious high-quality goals to achieve a good status for European lakes and rivers primarily in ecological terms, gives details about the essential processes as well as instruments, and includes everything into a strict time schedule.

Aim

This article adresses progress and shortcomings at the implementation of the WFD in general and with reference to two selected case studies (Rivers Elbe and Upper Danube).

Results and Discussion

After introducing the WFD, its aims and exceptions, a policy summary and background document ‘Environmental objectives und the Water Framework Directive’ and the use of Environmental Quality Standards (EQS) for single ‘priority substances’ as well as ‘hazardous priority components’ is discussed. The initial characterization undertaken by the German states revealed that only about 14% of all surface waters are considered to meet the WFD objectives by the year of 2015. Approximately 60% of the water bodies assessed are at risk of failing the WFD objectives, if not systematic efforts are made to improve the quality. Screenings of sources and paths of exposure for ‘priority substances’ and ‘priority hazardous substances’ according WFD identified one distinct pollution source for surface waters: ‘Historical pollution from sediments’. Because of industrial emissions in the past several river catchment areas are expected to fail the standards demanded by the WFD, due to a risk of remobilization of contaminants from sediments. This holds true for the Rhine river with high loads of hexachlorobenzene (HCB) as well as for Elbe river, where contaminated sediments can be a severe problem. Therefore, integration of sediments into the holistic river basin management approach and their consideration within the ‘programmes of measures’ scheduled for 2009 is highly recommended. At present, a comprehensive weight-of-evidence study verifies whether the observed fish decline at the Upper Danube. River is caused by ecotoxicological hazard potentials of contaminated sediments.

Outlook

Combined investigations of sediment contamination and mobility as well as acute and mechanism specific biotests in effect directed analyses/weight-of-evidence studies show grent potential for the assessment of chemically polluted rivers and should be included into the ‘programmes of measures’ within future management concepts.
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