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1.
Air pollution in the region Leipzig-Halle was investigated using two-year-old pine needles (Pinus sylvestris L.) at 39 sites of a biomonitoring net covering an area of ca. 7 500 km2. The concentration values of Al, Ca, Cr, Fe, K, Mg, Mn, Pb and V characterize the immission patterns of the period 1990/91. The method is less suited for Cu, Ni and Zn due to the transfer route soil-pine, and for Cd due to the small total content. There are significant spatial and element-specific variations which require distinct evaluation of the pollution situation. The city of Leipzig itself is a significant source for Pb, Cr, Fe and V emission. Mainly as far as the centre of the region is concerned, the Pb concentration values are beyond those of heavily contaminated reference sites. The bioindication system is also applicable for comparable regions in Eastern Europe where the pine is the dominating conifer type. Immission trends can be monitored over ecologically relevant periods of time.  相似文献   

2.
The deposition of heavy metals bound to air dust and their ecological effects depend, to a large degree, on particle size, which influences the transport processes in the environment. To estimate the size range of the particles mainly taken up by the pine needles, concentration gradients along a sector leeward of Leipzig were modelled according toGauss plume calculations. The results show that the aerodynamic size is between 1 and 10 μm. Particles of this size range can be taken up by lungs and, thus, have a particular toxicological relevance.  相似文献   

3.
4.

Goal and Scope

Details about the ecological function of lake shores as ecotones between land and lakes are not well-known. These ecotones are also heavily exploited and, in part, considerably changed. Whereas anthropogenic nutrient loading is decreasing, structural changes are increasing. Unfortunately, there is a deficit in methods of evaluation and decision processes.

Main Focus

Even the EU-water framework directive was no remedy for this deficit, as lake shores were included only implicitly. In this article several evaluation methods and their conceptual groundwork are presented. However, these methods were not developed for lake shore research. Therefore, criteria are proposed which could fulfill the specific demands of lake shore assessments. The management of lakes shores should consider structural and biological parameters, and be agreeable to local residents.

Results and Conclusions

In addition to conventional biodiversity methods, the ecology of lake shores could also be represented by a functional food net, for example in benthic invertebrates. But even quantification of biodiversity alone creates many problems. A simple biodiversity index cannot meet all the demands placed on a method of evaluation in complex situations, especially when coupled with additional information on structure, practicability, costs, etc. For these reasons, assessments for future management cannot be based on such an index.

Outlook

A possible approach to include this complexity in assessments is to apply mathematical models and theoretical order concepts.  相似文献   

5.
In contrast to the complex N-cycle with its high number of reactive compounds, the global P-cycle is uncomplicated. There is only one reactive compound (PO4 3?), and the atmosphere is practically not involved. Nevertheless, severe ecological imbalances may be induced by anthropogenic perturbations of the P-cycle, especially in aquatic ecosystems. The present knowledge on the global P-cycle (reservoirs, fluxes, residence times) is summarized and the ecological dimension of increased phosphorus inputs into surface waters is discussed in detail. Exemplary for Germany, the role of agriculture is described in this context. The fact that the rock phosphate resources are principally limited and not renewable is of a high ecological and economical relevance. The expected lifetime of the P-reserves is calculated for different estimate-scenarios concerning the magnitude of reserves and consumption. Measures to reduce the P-surplus in agriculture, to increase the efficiency of P-fertilization, and to recycle P more consequently are therefore highly required.  相似文献   

6.
10 years ago, the WWF (World Wide Fund for Nature) began to support the work of environmental protection in the countries of Eastern Europe. A main topic is the Danube-Carpathian Program. With the beginning of the bombardements, connected with great amounts of chemicals released directly and as clouds from the fires and explosions, the question raises: What are the consequences for mankind and nature? Is there a risk for the Danube-Carpathian Program? The WWF feels responsible for reporting about these consequences. In July 1999, a group of two Oil Experts and two scientists (each a chemist and a toxicologist) visited Belgrad, Pan?evo and Novi Sad, took samples of soil and water, and estimated the contents of dangerous substances. The first findings and the first consequences for nature and human health are described.  相似文献   

7.
The development of criteria for the comparative assessment of technologies and substances beyond the toxicological approach and the development of an integrated pattern of criteria is still at the beginning. The criteria presented here for integrating the precautionary principle into the substance and technology assessment have to be further operationalised and completed, in the same way as the criteria which have been discussed and developed within the framework of
  • - the poisoning and pollutant paradigm
  • - the equilibrium paradigm
  • - the sustainability and “Mitwelt” paradigm
  • - the energy and the general technology assessment debate.
  • The resolution of the criteria has to be improved and their range (which is certainly limited) has to be explored more precisely. The application of the criteria should never occur mechanically. Technology assessment and substance assessment are not only scientific, but essentially social and, hence, discursive processes. It is not so much the assessment of individual substances which should be in the center of the debate, but rather the comparative assessment of competing techniques, substances and substancerelated development pathways (see vonGleich andRubik, 1966 as a first approach to assess the environmental effects of old and new materials). According to the example of the energy strategies, only the development of competing strategies in the substance field could create the necessary prerequisites for a broad public discourse and thus for a democratisation of the basic substancerelated policy decisions. This discourse is a duty which science and economy have toward society.  相似文献   

    8.
    The development of criteria for the comparative assessment of technologies and substances beyond the toxicological approach and the development of an integrated pattern of criteria is still at the beginning. The criteria presented here for integrating the precautionary principle into the substance and technology assessment have to be further operationlised and completed, in the same way as the criteria which have been discussed and developed within the framework of
  • - the poisoning and pollutant paradigm
  • - the equilibrium paradigm
  • - the sustainability and “Mitwelt” paradigm
  • - the energy and the general technology assessment debate.
  • The resolution of the criteria has to be improved and their range (which is certainly limited) has to be explored more precisely. The application of the criteria should never occur mechanically. Technology assessment and substance assessment are not only scientific, but essentially social and, hence, discursive processes. It is not so much the assessment of individual substances which should be in the center of the debate, but rather the comparative assessment of competing techniques, substances and substancerelated development pathways (see vonGleich andRubik, 1966 as a first approach to assess the environmental effects of old and new materials). According to the example of the energy strategies, only the development of competing strategies in the substance field could create the necessary prerequisites for a broad public discourse and thus for a democratisation of the basic substancerelated policy decisions. This discourse is a duty which science and economy have toward society.  相似文献   

    9.
    Ecosystems and biocoenoses are exposed to multiple mixtures of environmental pollutants, but the usual risk assessment of chemical toxicities is focussed only on the judgement of single substance toxicity. With the two biometrical models concentration-addition and independent action known from pharmacology and toxicology, a pragmatic way for the analysis of combined effects is possible using the experimental knowledge of single substance toxicity. A short introduction to the models is given and an appropriate experimental design for mixture toxicity analysis is outlined. The principal suitability of the concepts was verifed in two different bioassays (green alga; luminescent bacterium) with the analysis of binary and multiple mixture toxicities of environmental chemicals. In this paper we present the results obtained with the green algae bioassay. Congruent results from the bioluminescence inhibition assay can be found in Grimme (1998). The results obtained indicate that the toxicities of mixtures of chemicals can be studied experimentally, even at low concentrations of the individual components. Mixture toxicities were detected at low, statistically non-significantly acting concentrations of the single compounds. These results force one to take mixture toxicities into account when environmental standards are established.  相似文献   

    10.
    Ecoregionalizations are important for the evaluation of monitoring networks. In this article a method is decribed concerning how to define Germany’s ecoregions by using ecological data on soil, vegetation, climate and elevation through the aid of classification and regression trees. The resulting ecoregions can be linked to metadata (parameters, methods, quality control and assurance measures) from thousands of Germany’s environmental monitoring sites. Together with GIS procedures, multivariate statistics and geostatistics, ecoregions are useful for integrating data of environmental measurements according to ecological and spatial criteria.  相似文献   

    11.
    Introduction Stress proteins are ubiquitous and inducible by a vast number of stressors. Their relevance for ecological and microevolutionary adaptations has been investigated since the early 1990s. Stress proteins: function and induction Stress proteins are categorized in different families of which most data have been recorded for Hsp70, Hsp60, and Hsp90. These cytoplasmatic proteins play a central role in protein folding, the trans-membrane passage of proteins, and the stabilization of signal transduction pathways. Hsp70 is induced by elevated concentrations of unfolded or malfolded intracellular proteins and hence indicates proteotoxicity. Modulation of the stress protein level by internal factors During certain developmental stages, stress protein levels are modified by internal factors. This has been particularly shown for the early ontogeny, for the formation of quiescent stages, and for the reproductive phase. Adaptation to external stressors in the laboratory Laboratory studies on the effects of ecophysiologically relevant stressors have revealed short-term physiological adaptation to heat or environmental chemicals to involve an elevation of stress protein levels. Extreme stressor impact disrupts this responsive mechanism. Adaptation to field situations Also in the field, physiological responses to temperature fluctuations or contamination usually involve the induction of stress proteins which can be used as a biomarker of proteotoxic effect. Implications for evolutionary biology In long-term contaminated sites, however, phenotypes displaying low stress protein levels appear to be evolutionarily favored. Whether different stress response strategies may entail different degrees of phenotypic variation even under natural conditions – via Hsp action on developmental canalization – is a matter of hot debate.  相似文献   

    12.

    Aim and Scope

    This study was aimed at evaluating environmental effects of tar-oil impregnated (tanalized) tree stakes using simple and efficient biotests to obtain results of its ecological impacts during the tar-oil breakdown in the stake.

    Results

    1. Soil respiration was measured in-situ as an indication of soil microbial activity in two field trials. Soil respiration was measured in a 20 year-old apple orchard at various distances from the tar-oil impregnated tree stakes and also on soil mixed with chippings from pine stakes with tar-oil impregnation of different ages.
    2. Cress germination tests were employed to evaluate tar-oil phytotoxicity in a field and laboratory trial. Cress was seeded close to tree stakes in the same 20 year-old apple orchard and germination rates related to tar oil-impregnation. Cress was also seeded in trays in sand mixed with pine chippings from stakes with tar-oil impregnation of different ages.
    3. The portion of the carcinogenic benzoapyrene (BaP) ranged between 0.0015% in freshly tar-oil impregnated to 0.4% in tar-oil impregnated 20-year old trees stakes, i.e. irrespective of the overall PAK concentration and its degradation.
    4. Kinetic analysis using DIXON plots showed a 50% breakdown of overall PAHs after ca. 2.7 years, i.e. km or Ki values of less than 3 years.

    Conclusion

    Germination tests of cress and endogenous seeds as well as soil respiration proved sensible indicators of the phytotoxicity and ecotoxicity of tar-oil impregnated tree stakes in fruit orchards. Soil respiration proved particularly sensitive to tar-oil ageing. Its combination with kinetic inhibition models resulted in parameters suitable for the interpretation of results.  相似文献   

    13.
    14.
    15.

    Goal and Scope

    Since many years mineral and plant oils have been applied with relatively high doses to control noxious insects in sevral agricultural and horticultural crops. In addition they have also been used with low doses as adjuvants (additives) together with herbicides to improve their efficacy. Their ecotoxicological effets on soil microorganisms as an important part of the soil fertility, however, have been insufficiently investigated.

    Methods

    Under laboratory conditions two agricultural soils were treated with a rapeseed oil and a paraffin oil as well as in some cases with biocidal reference compounds (e.g. dinitrophenol herbicides). The applied dosage were related to the concentrations in soil reached after simulated penetration of practical field amounts into upper soil layers. In some cases green manuring was simulated by adding lucerne meal to the soil. During incubation for several weeks biomass-related microbial activities (dehydrogenase activity, substrate-induced short-term respiration) as well as the mineralization of carbon and nitrogen (including nitrification) were measured. In addition some combinations of these activities were investigated.

    Results and Conclusion

    As compared to ‘normal’ pesticides both oil products differed in their effects on soil microorganisms. Those effects typical for strongly biocidal compounds including plant protection products, namely a dose-related inhibition of microbial biomass and stimulated mineralization (especially of nitrogen) failed with the tested oily compounds. Depending on the high input of organic carbon by these oils and their rapid decomposition a dose-dependent increase of biomass-related parameters and of the carbon mineralization occurred especially with the high doses, whereas the nitrogen mineralization was reduced or even the available nitrate content was nearly eliminated for some time by microbiological immobilization. In comparison with the reference products the two oil preparations caused only little microbiological-ecotoxicological impacts on the soil and even some stimulations of important microbial soil parameters when tested with the extended test system (including the dosages used).

    Recommendation and Perspective

    As a result of these investigations and of the existing literature we recommend an extension of the test spectrum for those formulated preparations and adjuvants which should be applied at high dosages or if they contain higher amounts of well decomposable organic substances. This is necessary to distinguish dose-related enhanced activities induced by biocidal effects and the subsequent mineralization of this death material (=indirect effects) from ‘real’ stimulations directly produced by the substrate.  相似文献   

    16.
    17.

    Goal and Scope

    Type III Environmental declarations (Environmental product declarations, EPD) are intended to inform interested parties about the environmental performance characteristics of products. They are based mainly on LCA according to ISO 14040ff, provide its results as inventory or impact category indicators and thus describe the product system under investigation. ISO 14025 is out for ballot as FDIS. The concept of EPD has found a market in particular in the construction sector. It has a considerable part in the European Integrated Product Policy, e.g. documentation of improvement in design for environment, documentation of compliance with green procurement requirements.

    Main Features

    EPD are a means to communicate the results of a LCA-study according to ISO 14040ff in a comparable and harmonised way. ISO (FDIS) 14025 describes how to develop and document consistent and comparable data sets. This report exemplifies three levels in the development of EPD for which the standard provides requirements. 1. Framework for the development of an EPD program including verification procedures for EPD. 2. Defining the rules for conducting the LCA according to ISO 14040ff as well as additional information for defined product categories (product category rules). 3. Development and documentation of EPD according to the PCR.

    Results and Conclusions

    After quite a few years of standardisation work the new standard ISO (FDIS) 14025 will provide a systematic approach to documenting and communicating LCA results in an EPD. This will support propagating LCA from its academic origin to a practical tool for the assessment of the environmental performance of a product system. An essential part will be the participation of LCA experts in EPD programs.

    Recommendations and Outlook

    An enormous effort for developing appropriate conventions will have to be taken by all interested parties to come up with consistent and comparable EPD in different branches. In some areas defining such conventions has been shown to be possible. An important part is the development of quality criteria for modelling as well as for the databases used to calculate the LCA. To find sufficient credibility at economically acceptable conditions with a minimum of bureaucratic effort more practical experience will have to be gained. This holds especially for the trust in the EPD results based on the independence of the review, transparency of procedures and the participation of interested parties. There is a demand on education for SME developing EPD for their products as well as for the users of EPD on how to document EPD transparently and apply them properly.  相似文献   

    18.
    For the determination of mineral oil hydrocarbons in water and soil, IR-as well as GC/FID-methods (DEV H-18, ISO/TR 11046, NEN 5733) are used. Independent of the measurement method, different clean-up procedures are prescribed in these standard methods. Aluminium oxide, silica gel and magnesium silicate (Florisil®) are used as adsorbents. This article describes the problems of clean-up occurring in mineral oil analysis using selected substances. Tests concerning the type of adsorbent, extract medium, clean-up-technique and extract/adsorbent-ratio are presented. It will be shown that the clean-up procedure has to be counted as a significant factor of influence in the determination of mineral oil hydrocarbons. The sources of errors resulting from clean-up as well as the possibilities to avoid them are presented. An extraction solvent for soils which is simple to handle and optimally adjustable to the requirements of the clean-up procedure is presented.  相似文献   

    19.

    Background, Aim and Scope

    Acute toxicity and estrogenic potency of six nonylphenol isomers, with nearly the same chemical structure and the same physico-chemical properties, were investigated in this study. Thes datasets give some insight into how far structure activity relationships can be used for these modes of action.

    Methods

    The toxicity of the isomers was investigated by the daphnia immobilisation test as well as the duckweed growth inhibition test. The estrogenic potency of the p-NP isomers was analyzed by MVLN-Reportergen-Assay.

    Results

    No differences between the isomers were found for baseline toxicity, neither in the daphnia immobilisation test nor in the duckweed growth inhibition test. Estrogenic potency of the isomers in the MVLN reportergen assay was markedly different for the tested isomers. The highest estrogenic potency was found for p353-NP, whereas p262-NP and p22-NP exhibited no estrogenic, but partial antagonistic potency in this assay.

    Discussion

    The results from this study clearly indicate how far simplification and structure activity relationships can be used in risk analysis. For bioconcentration and baseline toxicity structure activity relationships are possible and will allow simplification of the risk analysis. For special modes of action simple structure activity relationships are per se impossible. This was shown especially for the estrogen receptor interactions, where only small structural differences can lead to different modes of action.

    Conclusions

    It seems possible to reduce the effort for risk analysis, using combinations of measured data and predictive models. At the moment it seems unlikely that predictive models alone will and can be used for risk analysis.  相似文献   

    20.
    Background and objectives There is an urgent need to detect, assess, and reduce effects of hormonally active compounds and endocrine disrupters in aquatic systems, as reflected in national research programs like the Swiss NRP 50 “Endocrine Disruptors” and its consensus platforms. As a medium-term measure, the EU strategy on endocrine disruptors (SEC(2007)1635) uses the Endocrine Disruptor Testing and Assessment (EDTA) Task Force of the Organisation for Economic Co-operation and Development (OECD) along with other research activities. In particular the test methods of the OECD that are currently in validation or already validated may contribute to a better understanding of the extent of endocrine disruption, in particular if they are applied on environmental samples and in the context of risk-assessment strategies, for instance in waste water treatment. This article aims to give an overview and an evaluation on available and validated biological test systems for the detection of endocrine disruptive and reproductive effects in aquatic systems. Based on this a recommendation for a modular ecotoxicological test platform is given. The study focuses on test methods for sex hormone active substances. Material and methods On the basis of an extensive literature search and ongoing international validation efforts by the OECD for methods to detect endocrine disruptive effects, 15 biological test methods (5 in vivo and 10 in vitro) were selected. Comprising, for example, of eight OECD methods and three out of five in-vitro methods mentioned in the Global Water Research Coalition (GWRC) report “Tools to detect estrogenic activity in environmental waters” (Leusch 2008). Experienced users and developers were then asked to rate the test according to given relevant criteria. The resulting criteria profiles were compiled, compared, and evaluated. Results The methods were selected on the basis of validation status, distribution, their suitability for standardisation, and their proven sensitivity for environmental samples. We assumed that specific YES/YAS-procedures and the ER/AR Calux systems achieve the mentioned criteria. In the case that strong cytotoxicity of environmental samples affects the applicability of cellular reporter gene assays, alternatively a molecular receptor binding assay (e.?g. ELRA) could be used. Additional molecular receptor binding assays are currently in validation by the OECD. Modulating effects on steroidgenesis and probably even on aromatase activity can be detected by the OECD validated H295R Steroidgenesis Assay. Its applicability for environmental samples is currently tested. As in-vivo methods different fish assays (e.?g. Fish Screening Assay and the Zebrafish Embryo Test) were evaluated. For the detection of effects on the thyroid-associated hormone system the Amphibian Metamorphosis Assay (XEMA, for Xenopus Metamorphosis Assay) will soon be available as an OECD-Guideline. Because of trends in the international community to avoid tests with vertebrates in the future, only an optional recommendation was given for such tests. Reproduction toxicity, on the other hand, can be sensitively tested by the tests using the gastropod Potamopyrgus antipodarum, which, as invertebrate tests, do not require a permit to perform animal testing procedures. This test is also sensitive for many substances which are able to induce an endocrine disruption in vertebrates. Its validation is currently performed by the OECD. The applicability of the herein proposed test methods of the modular test platform for environmental-sample assessments were previously confirmed by several published scientific studies. Discussion We propose several test methods to be included in an application-oriented modular test platform. These tests should be suitable to efficiently indicate different mechanisms of endocrine disruption and reproduction toxicity, and may be employed in different situations according to their respective advantages. The modular test platform is able to detect impacts on the reproduction relevant effects in invertebrates, amphibians, and fishes. Furthermore the different mode of actions of estrogenic and androgenic receptor binding, steroid genesis and perhaps even the modulation of aromatase are detectable. A research report on the relevance of endocrine substances and pharmaceuticals in aquatic environments (Moltmann et al. 2007) showed that endocrine end-points of in-vivo tests (31 of 71 tested substances) tend to be more sensitive than general ecotoxicological end-points, such as mortality and growth. Consequently, endocrine and general-toxic effects should be detected in an integrative manner by ecotoxicological test platforms. Conclusions By combining literature research with a targeted query for information about the chosen test procedures it was possible to obtain a detailed overview about the current state-of-the-art of science and technology in the detection of hormone-active effects and reproduction toxicity. Ecotoxicological and regulative aspects were considered equally, and the applicability of the test procedures was evaluated. Because of the diversity of endocrine disrupting mechanisms, a modular combination of in-vivo and in-vitro methods in a joint test platform is needed to recognise and differentiate the transitions from hormone-active effects to endocrine disruption. Recommendations and perspectives Our study leads to a proposal of a modular ecotoxicological test platform, which offers an integrative detection of hormone-active and reproduction-relevant effects in the aquatic environment. The modular system presented here allows the switching between test modules according to the continuously developing state-of-the-art of science and technology as well as the incorporation of novel developments. Further standardisation of such methods for regulative applications is recommended.  相似文献   

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