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1.

Background

The analysis of the intrinsic effects of perfluorinated organic surfactants shows the group to have a characteristic overall picture:
  • -high polarity
  • -high thermal and chemical stability
  • -ubiquitous distribution
  • -non-biodegradability
  • -multiple toxicity
  • In addition, certain substances belonging to this group (e.g. PFOS) exhibit a very long retention time in the human body. Toxic properties vary and, like the mechanisms for global distribution, have not been fully clarified. In the meantime, individual members of this substance group have been (are being) removed from the market. This report shows that in future the planned EU chemicals law (REACH) can be used to prevent such substances being regulated after they have been distributed in the environment and thus after damage has already occurred. To this end, however, the requirements for registration for low tonnage substances (1–10 tonnes/a) must be supplemented with specific tests (in particular on biodegradability)

    Aim and Scope

    The aim of the work was to analyse the intrinsic properties and risks of a subgroup of fluorinated organic substances.

    Results

    A summarising article describes the toxic effects and properties of a group of substances selected from the approximately 30,000 existing substances. With regard to the ongoing debate on revising the European regulations of existing substances (REACH). it is apparent that standardised test requirements cannot be applied to impact and risk analyses which are at times highly complex. For governments, REACH only provides the starting points for this process in the form of prescribed standard tests. If a substance (or a substance group) draws attention, more detailed tests must be carried out by the industry itself in the framework of responsible care and in the framework of the evaluation step of REACH. It is therefore important that the standard requirements of REACH are selected appropriately. In this respect, the study reveals some serious deficiencies in the Commission proposal.

    Conclusion

    The standard information for low tonnage substances (1–10 tonnes/a) must be supplemented in particular with an obligatory test on biodegradability. The possibility provided by the REACH dossier to evaluate substances on the basis of group observarions (SAR, QSAR e.g.) is to be welcomed.  相似文献   

    2.

    Background

    Aim and Scope. Implementation of the European Union White Paper on chemicals policy shall provide more safety and more transparency in chemicals use. In the past, when assessing existing commercial substances there was often a lack of information in the fields of application of the chemicals and the exposures arising in those contexts. The White Paper therefore calls for ‘shared responsibility’. Processors and commercial users of substances are to be involved much more closely in the risk evaluation process than has hitherto been the case. They are to provide data on substance applications and exposures, and, to some extent, they are also to carry out exposure assessments and risk assessments themselves. By analysing case studies, the paper highlights the consequences of this approach.

    Results and Discussion

    Fear has often been voiced that these new tasks will completely overburden small and medium-sized enterprises. It is assumed that many chemicals are no longer available for smallvolume applications, as — for cost reasons — producers do not include these applications in their registration. The wording of the White Paper is not precise enough to be able to appraise the costs that will be associated with the required intensified communication. In this situation, it is essential to analyse prototypical substances and their applications in order to gain an improved understanding of the principle of shared responsibility.

    Conclusions

    The concrete study of several product chains has shown that the flow of information required between producers and users is very likely feasible within the context of the REACH system. For the producers of chemicals, the intensified communication will presumably make it simpler to procure information in the fields of application and exposures. However, in order to avoid users being overburdened, it will be important that registration requirements and focuses are shaped in a manner doing justice to practical realities. Users will need to undertake community-wide efforts on an industry federation and branch level. In this context, the protection of company know-how also needs to be ensured.

    Recommendation and Outlook

    In practice, implementation of the principle of shared responsibility can lead to intensified communication among the producers and users of chemicals. This can greatly facilitate exposure assessments and risk assessments. There is a need to develop manageable procedures that can also be implemented by small and medium-sized enterprises. Numerous proposals have been made in this context, and extensive reference material is now available.  相似文献   

    3.

    Aim and Background

    In 1999, under German Presidency, the European Council asked the European Commission to set up an approach with new instruments for a new European strategy on chemicals management. In 2001, the Commission subsequently published a White Paper called ‘Strategy for a future European chemicals policy’. After intensive discussions with all involved parties, a proposal for a new Regulation, called REACH, was brought in to Council and Parliament (co-decision procedure) in October 2003. Different impact assessments concerning the strategy of the White Paper presumed dramatically increasing costs for the chemical industry. Due to these discussions, the Government of North Rhine-Westphalia decided to conduct a pilot project on workability of the new requirements in the second half of 2003. The parties involved were administrations, producers, industrial associations, unions and NGOs. The focus was not to test the entire Regulation, but to analyse the practicability of selected processes, evaluations, and communication processes connected with the registration of substances.

    Results

    Examining the requirements and processes with regard to their realization in practice, resulted in a list of well-founded proposals. These proposals concern modification in the Regulation itself, implementation tools required, and guidelines which will need to be available before the REACH system is launched. The pivot questions of the pilot testing were the acceptance of data of substance-effects and their evaluation in different application areas. The registration Agency (played by the German Competent Authorities) checked the presented documents concerning completeness and plausibility. For all presented papers inquiries were needed In summary, the simulation has provided concrete evidence of where and why REACH may cause problems. Lack of simple instruments and corresponding knowledge for conducting exposition scenarios were noticed. The simulation process facilitated a new communication of all parties along the supply chain. In addition, the development of new networks could be observed to ease co-operation between authorities and those active on the market. These networks continue to exist even after cessation of the pilot trial.  相似文献   

    4.

    Background

    European chemicals legislation (registration, evaluation, authorisation and restriction of chemical substances (REACH)) requires a broad assessment of chemicals with respect to, inter alia, their health-relevant properties. Due to the extreme number of substances to be assessed and the limited current toxicological knowledge on their respective properties, REACH implicitly requires a paradigm change: away from knowledge generated mainly from costly animal experiments towards the use of mechanistic findings. Moreover, effect mechanisms at the biochemical or cellular level are essential when conclusions shall be drawn about "new" endpoints and mixtures of xenobiotics. This study (funded by the German Federal Environment Agency) describes examples of biochemical processes in the mammalian organism and how xenobiotics interfere with them. Interference with physiological processes expected to lead to adverse health effects is characterised as "toxicity pathway". The study describes toxicological endpoints not usually covered in routine animal testing and the respective toxicity pathways.

    Results and conclusions

    Screening for chemicals which exert effects via common toxicity pathways and subsequently conducting targeted short-term tests may generate new information about the toxicity of chemicals without performing extensive substance-by-substance animal experiments. Information on common toxicity pathways may also provide input for the assessment of mixture effects. The U.S. Environmental Protection Agency is working intensely on this concept. It involves the use of enormous amounts of data on relevant biochemical and cellular processes, which are generated by "high-throughput screening" methods, and then are combined with substance-specific kinetic data, experimental apical test outcomes and modelling. Current limitations in the regulatory use of this integrated approach on risk assessment will be outlined.  相似文献   

    5.

    Background

    The Cefic Mixtures Industry Ad-hoc Team (MIAT) has investigated how risks from combined exposures can be effectively identified and managed using concepts proposed in recent regulatory guidance, new advances in risk assessment, and lessons learned from a Cefic-sponsored case study of mixture exposures.

    Results

    A series of tools were created that include: a decision tree, a system for grouping exposures, and a graphical tool (the MCR-HI plot). The decision tree allows the division of combined exposures into different groups, exposures where one or more individual components are a concern, exposures that are of low concern, and exposures that are a concern for combined effects but not for the effects of individual chemicals. These tools efficiently use available data, identify critical data gaps for combined assessments, and prioritize which chemicals require detailed toxicity information. The tools can be used to address multiple human health endpoints and ecological effects.

    Conclusion

    The tools provide a useful approach for assessing risks associated with combined exposures to multiple chemicals.  相似文献   

    6.

    Background, Aim and Scope

    Many environmental pollutants are slowly degrading (persistent) and very mobile. They are semivolatile, i.e. they are partitioned between the environmental media of soil, water and air, and undergo long-range transport. The combined action of climate and substance properties determines the distributions and fate of these substances, among them as the persistent organic pollutants (POPs), other pesticides and industrial chemicals.

    Main Features

    Multicompartment chemistry-transport models are under development in order to study environmental exposure models.

    Results

    The investigation of transport and fate of some POPs on the global scale has emphasized the significance of historically explicit and geo-referenced simulations for substance distributions, persistence and long-range transport potential. Apart from the substance properties, it is the regional climate which is most important. This was illustrated by studies into the regional cycling of DDT and γ-HCH in selected tropical and extra-tropical regions.

    Discussion

    The isolation of individual steps of subsequent cycles of emission, transport and deposition (a so-called grasshopper effect) in model experiments shows the potential to elucidate the complex superposition of substance properties and environmental conditions, variable in time and space.

    Conclusions

    The results suggest that the grasshopper effect enhances the long-range transport potential, but is not required to explain an accumulation in polar regions (at least for γ-HCH).

    Perspectives

    A number of relevant scientific questions should be addressed by exposure modelling.  相似文献   

    7.

    Background

    Sorting and disposal of waste are the last steps in the “lifetime” of a product. If products are contaminated with chemicals assessed to be hazardous for man or environment, waste management has the role of a vacuum cleaner in substance chain management working in two different ways: The hazardous compounds have to be properly separated from potential secondary resources in sorting processes. If this is not possible, those products have to be disposed safely. Starting from the experiences collected with some chemicals banned, the tools used for phasing out these chemicals from the technosphere are studied with respect to their influence on the contamination of the environment.

    Results

    Even if a dangerous substance has been banned, it is further used in a number of products. In the cases presented here, the substances were banned for further use. In the case of CFCs, the substitutes used have partially also been substituted because of adverse effects. Besides the prohibition of use of hazardous substances, numerous other regulations were issued to reduce unsafe handling and minimize emissions into the environment. It turned out that waste management cannot correct mistakes which already happened “upstream” in the product chain. The control of point sources works quite successfully, whereas today the overwhelming emissions stem from diffuse sources, partially caused by unsafe waste management procedures.

    Conclusions

    Though there are no complete balances for both groups of compounds serving as examples, some conclusions can be drawn based on the experiences collected. Hazardous compounds may be separated successfully from used products or waste,
    • If they are mostly used in industry and not in households,
    • if they can be identified as part of certain products,
    • if their concentration in these products is rather high,
    • if technical problems come up when they contaminate secondary raw materials,
    • if there is international support for proper waste management.
      相似文献   

    8.
    9.

    Aim and Background

    Varying interpretations of the hazard potential of native oils and fats for aquatic ecosystems have led to conflicting international and national regulations. Background is the different consideration of physical effects. This study aimed at compiling published data on behaviour and effects of native oils and fats in water, hereby providing a basis for discussion on adequate classification of these substances.

    Results

    According to scientific data, physical effects may significantly contribute to the hazard potential of native oils and fats. This is especially important in risk assessment of spills, e.g. in the case of accidents. Basically, these effects are the same in marine and freshwater environments; the latter may even be regarded as worst-case situations with respect to physical effects.

    Recommendations

    Based on these facts, the German classification of native oils and their derivates as ‘not hazardous to waters’ according e.g. to § 19g of the Water Resources Act and § 4 of the Ordinance of Hazardous Substances should be revised. New criteria need to be incorporated into the evaluation procedure to allow an adequate assessment of these substances regarding physical effects.  相似文献   

    10.
    11.

    Goal and Background

    As a consequence of the implementation of EU Directive 98/8/EC into national law in June 2002, all biocidal products will be subjected to an authorization procedure. Condition for issue of an authorization is that the product or its residues do not exert unacceptable effects on human and animal health or on surface water and groundwater. Hence, among other issues, impact of wood preservatives on groundwater is to be assessed. Focus is particularly on impregnating plants with open-air storage sites for treated wood.

    Methods

    Based on already in-use versions of the leaching model PELMO, an advanced version (MC-PELMO 3.0) was developed with a specific focus on estimating groundwater contamination under storage sites at wood preserving facilities in Germany. The model processes twenty-two different leaching scenarios that were derived from twelve characteristic soil profiles representing pedological regions in Germany along with recorded meteorological data from nine weather stations. These data are related to geographic distribution of industrial wood preserving activity. The model calculates statistic probabilities of concentrations of wood preservatives in seepage water beneath timber storage sites of regions to be selected by the user.

    Results and Discussion

    The reports provided by MC-PELMO 3.0 include mean average concentrations, 55 to 99 percentiles, and single maximum concentrations for each of the scenarios. the results can be related to the total area of Germany, its forest area or to the density of preversation activity in various regions. Beside concentrations of the parent compounds, those of degradation products may be calculated for the seepage water.

    Conclusion

    The described model is a particularly useful tool for comparative assertion of various wood preservative products under aspects of the exposure of groundwater resources. Comparative assertion is a new element within EU-chemicals policy, for the first time materialized in the biocidal products directive 98/8/EC. Furthermore, the results of model calculations identify vulnerable regions in Germany for which appropriate risk management measures have to be taken in order to protect groundwater from contamination.  相似文献   

    12.

    Objective and Background

    PCB (polychlorinated biphenyle) are typical man-made environmental pollutants that cause a broad spectrum of effects in vertebrates. Although a lot has been studied about the toxic effects of xenobiotic substances on aquatic organisms, their subacute effects are not yet well known. Fish occupies a central position in freshwater food webs and therefore, carp was chosen to be our test organism. The aim of our study was the investigation of subacute effects of Aroclor 1254 (22μg l?1) on respiration, swimming activity, and biotransformation, allowing discussion of changed interaction between the available energy resources.

    Methods

    The respiration experiments under controlled laboratory conditions were run for 29 days (5 d before, 16 d with and 8 d after chemical exposure) with exposed carp compared to the non-exposed fish. Furthermore, the BehavioQuant system quantitatively monitors the positions of each individual fish before (8 d) and during (21 d) PCB exposure and swimming activity (number of horizontal turnings s?1) of animals was calculated. Thereafter, liver samples were taken from animals for analysis of the phase 2 enzyme activity (glutathione-S-transferase). In the respiration experiments were 6 exposure, 6 controll, and 3 solubilizer controll groups (12 animals each group); in the behavioral experiments were 9 exposure, 6 controll- und 3 solubilizer controll groups (6 animals each group), and in the enzyme activity measurements were 9 exposure, 6 controll and 3 solubilizer controll groups (6 animals each group) examined.

    Results and Discussion

    A clearly increased (33%) oxygen consumption due to the PCB-exposure is found to be reversible; after the exposure period the respiration of carp shows a level comparable to the oxygen consumption during non-exposure time. By evaluating quantitative behavioral parameters of animals, it becomes evident that the exposure to PCB also causes a reversible change in their swimming behavior. Chemical stress leads to a decrease of mean daily swimming activity combined with an increase of the mean number of turnings during the night. Thereafter, the swimming activity shifts to the circadian swimming behavior under control conditions. Furthermore, our measurement of soluble and microsomal glutathione-S-transferase activity of fish liver shows a significant elevation after exposure period.

    Conclusion

    Our results prove that it was feasible to detect sublethal effects of PCB-mixture on all parameters under these conditions successfully. Our findings imply that fish are able to cope with the chemicals and we purse the hypothesis that the higher physiological energy demand caused by increased activity of enzymes, which are involved in biotransformation of foregin substances, may be related to a higher respiration of fish stressed by xenobiotics.

    Recommendation and Outlook

    Further experiments should investigate the effects of PCB on ecophysiological parameters of carp fed with exposed natural food allowing discussion of ecological consequences.  相似文献   

    13.

    Background

    Current hydrological research is increasingly focusing on pharmaceutically active compounds (PhACs). Concerning the issue of quality of drinking water, this problem has also become the focus of public interest. However, in spire of the fact that the fate of chemicals in surface waters has been assessed in great detail, the influence of groundwater-exchange is yet only little known.

    Goal

    This study gives emphasis to the question of how transport and degradation of PhACs interact with the exchange of surface water with groundwater. Special interest is given to alternating groundwater regimes.

    Methods

    Based on a small stream system in the north of Berlin, Germany, a one-dimensional compartment-model was established using differential mass-balance. The stream which, at its mouth, discharges 0.3 m3 s?1 is already well investigated and thus provides a good empirical data basis. The processes taken into account by the model were ‘exchange of surface-water with groundwater’, ‘decomposition’ as well as ‘transport’ of PhACs. Calculations were performed using the commonly used analgesic Diclofenac as an example and defining 81 scenarios by different groundwater regimes. Hasse Diagramm Technique was used to compare the scenarios.

    Results

    All scenarios show a big influence of groundwater-exchange to the fate and concentration of PhACs in surface waters. In the case of the modelled stream system, dilution by groundwater was more responsible for a decrease in concentration than degradation was. Furthermore, on the background of a standard scenario, the loss due to groundwater by 5.4 percent was in the same magnitude as the loss due to decomposition (9.7 percent). A crucial difference between punctual versus linear afflux of groundwater has not been observed.

    Discussion

    The alteration of discharge resulted in a big influence of the case differentiation between ‘constant velocity’ and ‘constant cross-section’. Furthermore, the model was based on the assumption that groundwater was unloaded with PhACs or diluted very well in comparison to the stream. In contrast, regarding measurements in the catchment, groundwater could even be a diffuse source of the contamination of the stream.

    Conclusions

    The fate of PhACs in our model is crucially driven by interactions with groundwater. Therefore, assessing the risk emanating from substances like Diclofenac, it is very important to regard their accessibility to decomposition as well as the morphology of the stream-system and its interactions with the groundwater.

    Perspectives

    In this model, the process of transport from the surface to groundwater back to the surface was dealt with insufficiently; in order to be able to observe fully developed interaction in a further step of modelling, a groundwater-transportmodel should be coupled completely with a surface-water-model.  相似文献   

    14.

    Goal and Scope

    The state of the art on sources, transport and environmental fate, human exposure and toxicological risk assessment of dioxin-like polychlorinated biphenyls (PCB), and non dioxin-like PCB is described and summarized with focus on Germany and neighbouring countries.

    Methods

    Presentations and discussions of a two-days symposium in Germany are the primary source of information. The significance of dioxin-like PCB is evaluated in relation to polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF). For that purpose, toxicity equivalent concentrations (TEQ) of both groups of contaminants in environmental matrices are compared.

    Results and Conclusions

    TEQ values of dioxin-like PCB are comparable to those of PCDD/PCDF in many environmental media; in food of animal origin PCB-TEQ is even higher. In most media, the non-ortho substituted PCB 126 has by far the highest contribution to the PCB-TEQ due to its high toxicity equivalency factor of 0.1. Atmospheric (long-range) transport obviously plays the major role for the diffuse PCB contamination of the environment. The transfer atmosphere-plant is apparently the key process for the entrance of dioxin-like PCB into terrestrial food chains.

    Recommendation and Perspective

    In spite of the decline of environmental contamination with PCB and PCDD/PCDF, a significant part of the general population in Germany and other European countries currently exceeds the tolerable intake of dioxin-like substances. However, also the results of a new toxicological risk assessment of non dioxin-like PCB implicate the need of further reduction of PCB exposure.  相似文献   

    15.

    Background

    Since the 1960s the scientific community has become increasingly aware of the need for integrative and holistic approaches to solve environmental issues. It has not only been recognized that changing environmental conditions can alter toxicological properties of pollutants but also that susceptibility of organisms to man-made chemicals strongly depends on environmental factors. This is especially true with respect to the endocrine control of reproductive processes in many aquatic species including fish, which are mainly influenced by changes in the surrounding environment such as day length, temperature, water flow, etc. Thus, it is astounding that the use of integrative approaches to address the question of the ecotoxicological relevance of the disruption of endocrine and related reproductive functions is rate. As a consequence of this shortcoming, there is increasing demand both among scientists and politicians regarding more holistic approaches in the endocrine disruptor research.

    Aim

    This contribution aims to critically discuss current strategies and approaches as well as to identify alternative strategies in context with the environmental risk assessment of endocrine disruptors. This will be exemplified using an ecotoxicological study with bream (Abramis brama) that was conducted along a major European river, the Elbe.

    Results and Discussion

    Local bream (Abramis brama) populations collected along the river Elbe were characterized by different magnitudes and/or types of endocrine alterations. Although there is a relatively extensive data set available regarding its contamination with wide range of chemicals in the Elbe, it has not been possible to conclusively relate the observed endocrine effects to the exposure to individual compounds or mixtures of chemicals. However, during the gross morphological evaluations of the fish it was observed that at some locations a great number of the individuals caught were parasitized with the tapeworm Ligula intestinalis. Furthermore, statistical analysis revealed that a relatively great percentage of the variation of the biological endpoints observed both among individuals and sampling sites could be explained by the occurrence of this parasite. Overall, the findings of these studies indicate that there is a complex interaction not only among the exposure to chemicals and parasitism but also of both of these aspects with the occurrence of biological effects in fish.

    Conclusions

    The gaps in our current knowledge as well as the findings from the few studies available indicate, the there is a need to revise our current approaches to characterize and evaluate exposure scenarios regarding their potential to cause endocrine disruption in wild organisms. Given the complexity of most environmental exposure scenarios, involving multiple factors including anthropogenic and natural influences and their interactions, I therefore see the urgent need to initiate a discussion on more integrative approaches in this field in favor of true ‘ecotoxicological studies’ that integrate both ecology and toxicology.  相似文献   

    16.

    Background

    A vast amount of data on the concentration of substances in soils is being generated in environmental monitoring programmes. This data has to be assessed in terms of effects on terrestrial biota. Benchmarks for such an assessment have been missing up to now. This gap has been filled by the development of a concept for the derivation of ecotoxicologically based soil quality criteria (SQC) and the application of this concept to environmentally relevant substances.

    Objectives

    The derivation method was applied to arsenic. The derivation process was described in detail from the compilation of data regarding effects on microbial processes, plants, and soil invertebrates to the formulation of a recommendation for an SQC.

    Methods

    The conceptual framework for the derivation of ecotoxicologically based SQC was developed after reviewing national and international concepts for the assessment of the effects of substances on terrestrial communities. For the assessment of arsenic effects, all relevant biotic processes and trophic levels have been taken into account. Moreover, soil characteristics that may affect the toxicity to biota have been reviewed.

    Results

    Effects of arsenic on biota may occur at soil background concentrations or slightly above. There are only a few studies in which the influence of soil characteristics, such as soil pH, soil texture, and soil organic carbon, on the effects of arsenic has been investigated systematically. That is why the SQC was oriented on soil background concentrations for sandy soils (5 mg As/kg soil dw). A comparison of the SQC derived in this work with ecotoxicologically based soilquality values from Canada, Denmark, the Netherlands, and the United States shows an average value of 16 mg As/kg, with a range between 5 and 34 mg/kg. The variations in the soil quality values are mainly due to differences in the derivation approaches.

    Conclusions and Outlook

    The concept applied is considered suitable for the derivation of SQC designed to protect terrestrial communities against direct effects of substances in soils. Therefore, its use is planned to derive SQC for other environmentally relevant substances. In addition to compensation factors, statistical methods should be taken into account to compensate for risks which cannot be quantified. Furthermore, there is the need for an assessment of indirect effects of soil contaminants on birds and mammals.  相似文献   

    17.

    Background and aim

    Air pollution caused by oxidized and reduced nitrogen is distributed over wide areas of Europe at a high level. As an alternative or complement to physical measurements and modelling calculations, biomonitoring with plants provides techniques to assess amounts and effects of pollution from oxidized and reduced nitrogen compounds (depositions and concentrations). Many of the previously implemented techniques are based on well-proven standardised methods, e.g. documented in VDI guidelines, modified more or less for a biomonitoring of atmospheric nitrogen pollution. This paper gives a review of the techniques for a biomonitoring of atmospheric nitrogen pollution, their possibilities as well as their limitations.

    Main features

  • -diversity of the ground vegetation
  • -nitrogen accumulation in vascular plants
  • -exposure of vascular plants
  • -mapping of epiphytic lichens, bryophytes and algae
  • -nitrogen accumulation in lichens and bryophytes
  • -exposure of lichens and bryophytes
  • Results and Discussion

    Important response parameters are nitrogen concentrations in plant tissue (shoot, needle, leave) and biodiversity of plant species. These responses of vascular plants in many cases are influenced by other local varying conditions, in particular the soil. The exposure of vascular plants over a short period provides a standardised quantification of the total atmospheric nitrogen input in a model ecosystem. The enrichment of nitrogen in the plant tissue of bryophytes and lichens from the ground vegetation is closely correlated with the amount of nitrogen deposition. The diversity of epiphytic lichens and the response of exposed Hypogymnia physodes is more sensitive to ammonia than to nitrous oxide, whereas with the diversity of epiphytic bryophytes or the abundance of algae no significant correlation with atmospheric N pollution were found.

    Conclusions

    Some bioindication techniques provide a causeeffect related, partly standardised biomonitoring of nitrogen pollution. In some cases varying experiences with some biomonitors like the biodiversity of the ground vegetation, exposure of lichens, moss bags and grass cultures stress the need for more research in this subject.  相似文献   

    18.
    Aim and Background Currently, the protection from hazardous substances occurring in consumer articles is often insufficient. In this paper, we discuss whether this situation will improve relevantly in the course of the implementation of the new European regulation on chemical substances (REACH). Changes under REACH may be heterogeneous. Therefore, differential effects depending on the tonnage as placed on the market, on the amount of substances contained in an article, and depending on timelines and exemptions for meeting the legal requirements, are discussed in this paper, together with a presentation of some uses of substances serving as examples. Discussion and Conclusions If substances are adequately registered, all identified and supported uses including their use in articles should be assessed. Therefore, where the full implementation of the registration conditions applies a substantial improvement may be expected due to REACH. Usually, producers or importers of articles are not required to register substances contained in these articles. Instead, the manufacturer or importer of the respective substance is usually responsible for registration, if exposure to the substance cannot be excluded and emission of the substance from an article is not the intended purpose. This may differ for substances intentionally released from articles. Additional obligations for substances not intentionally released mainly apply to substances of very high concern (SVHC). For the latter, the producer or importer of articles has to notify the European Chemicals Agency (ECHA) on the occurrence of the respective SVHC in articles. This information is important, especially because substances in imported articles may not be registered in advance. Authorisation within REACH is a very far reaching and effective tool of the legislation. However, authorisation is not required for SVHC imported as components of articles. Therefore, one main effect intended by REACH, i.?e. the substitution of SVHC, may possibly be undermined by importers of SVHC in articles. Restrictions, as specified in Annex XVII of REACH, offer a powerful opportunity to improve health and environmental safety with respect to hazardous substances. We support an extended understanding of what is defined as a “substance of concern” in the context of restrictions. This definition should be broader than just what is currently covered by the term SVHC. Consequences of restrictions may equally apply to European producers and importers of articles from outside of Europe, which contain such substances of concern. Another instrument currently closely linked to SVHC (in its more restricted definition), is the obligation of the producer or importer of articles to provide information according to article 33 (REACH). The downstream recipient of an article has to be informed on the content of SVHC in this article and how its safe use is ensured. Warehouses, wholesalers and other traders may therefore be aware of the SVHC contained in articles and may look for substitutes without such ingredients. Also, consumers may request this information on SVHC (just provided on demand) and are thus enabled to decide to buy other articles with less hazardous properties.  相似文献   

    19.

    Background and Scope

    The marine shipping lanes have become the most important path for the invasion of foreign aquatic organisms. The increasing global trade results in an increase in the number of marine vessels. Without any protective measures, with every ship carrying foreign organisms the risk of biological invasions will rise.

    Results

    The International Martime Organization (IMO) of the United Nations developed a convention to reduce the transfer of organisms with ballast water. After the entry-into-force of this convention the fleet of the world has to be equipped with effective ballast water management technology before 2016. This article discusses potential options for action. To comply with the limit values of the ballast water convention, the current state of the art demands the use of active substances. Any decision on the approval of active substances used for ballast water treatment and the environmental impact assessment lies with the IMO. Proposed to day are UV-radiation, active chlorine, active oxygen, the creation of biocides through electrolysis and a change in gases contained in the ballast water. The technologies and the potential risks are presented.

    Conclusions

    Despite the introduction of an approval procedure by IMO any reliable assessment of the real risks involved in the use of biocides is impossible, as the risk assessment approaches have still to be developed. On the regulatory level, the main focus in data requirements for the risk assessment is on a comprehensive testing of the toxic potential of the biocides proposed. Strategies for the identification and evaluation of the chemical resulting from the treatment of limnic, marine and brackish water are not fully developed. An integrating assessment of risks involved in the introduction of foreign organisms versus the toxic effects of the substances used or created during treatment is still missing.  相似文献   

    20.

    Goal and Scope

    The transfer of various chemical elements from maternal food into human milk was investigated. Transfer factors (hereafter TF) food/mother’s milk were taken to represent those nuclides pertinent to radiation protection in order to estimate possible radioactive burdens of breast-fed babies.

    Methods

    A total of 23 mothers, mainly from the Euroregion Neisse (PL, CZ, D; all being in their mature phases of lactation), took part in this study (1998–2001), for time periods between two to eight weeks (8805 samples were analyzed). The diurnal uptake of elements was determined by the duplicate method.

    Results and Conclusions

    TF values determined for Ag, Au, Ba, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga, I, La, Mn, Mo, Nb, Ni, P, Pb, Ra, Rb, Re, Ru, Sb, Sr, Te, Th, Ti, Uo, Y, Zn, Zr were theoretically analyzed with the following result: metal ions transfer into mother’s milk mainly in coordinated states (i.e. bound to anionic ligands), with TF values which increase according to complex stabilities. Therefore it can be assessed that neither Cd nor Ba, both forming only weak complexes, pose hazards to breastfed children.

    Outlook

    There are relationships between transfer factors pertaining to certain elements and the amounts of others consumed by the mother; i.e. (changes in) consumption of one element influence the transfer towards women’s milk of another element. Accordingly, strategies can be developed to keep off hazardous substances — including fissiogenic radionuclides — from milk which is far more efficient than traditional isotopic dilution; however, iodide tablets are useful here, too.  相似文献   

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