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101.
Die von REACH ausgel?sten Ver?nderungen im Hinblick auf die neu definierte Verantwortung von Hersteilern und industriellen Nutzern werden beschrieben. Die Datenerfassung für Altstoffe und die damit einhergehende Verbesserung der Risikobewertung werden ab 2007 beginnen, aber mehr als zehn Jahre in Anspruch nehmen. Der erfasste Datenumfang l?sst Lücken im Bereich Arbeitsschutz offen. Der Schurz der Verbraucher vor Stoffen in Erzeugnissen bleibt unzureichend. Dennoch ist REACH ein gro?er Schritt nach vorn für die Chemiepolitik.  相似文献   
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On the basis of physico‐chemical data, such as water solubility and vapour pressure as well as acute toxicity tests we developed an ecotoxicological model for preliminary hazard assessment. By use of the reciprocal product from log H and LC50 we developed a suitable ranking system that allows us to predict potential damage to aquatic organisms through pesticides.  相似文献   
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One potential trade-off that bold individuals face is between increased predation risks and gains in resources. Individuals experiencing high predation and hungry individuals (or individuals with low body condition) are predicted to show increased boldness. We examined one behavioral trait previously reported to be associated with boldness (the time individual fish needed to emerge from shelter) in various populations of mollies (Poecilia spp.). Our study system included several southern Mexican surface streams with high piscine predation and high food availability, sulfidic surface streams with high avian predation, in which the inhabiting fish show reduced body condition, and a sulfidic cave, where predation and body condition are low. Our comparison revealed very short times to emerge from the start box in populations from non-sulfidic streams. In sulfidic habitats (whether surface or cave), it took individual Poecilia mexicana considerably longer to emerge from the start box, and the same difference was also found in an independent comparison between P. mexicana and the closely related, highly sulfide-adapted Poecilia sulphuraria. Fish reared under common garden conditions (in the absence of predators and hydrogen sulfide) showed intermediate boldness scores to the extremes observed in the field. Our data thus indicate that (a) boldness is shaped by environmental conditions/experiential effects, but is not heritable, (b) predation affects boldness in the predicted direction, but (c) low body condition leads to reduced boldness. Extremophile Poecilia spp. spend most of their time surfacing to survive under sulfidic and hypoxic conditions, which exposes them to increased levels of predations, but the fish forage on the bottom. Hence, in this system, increased boldness does not increase foraging success. We argue that energy limitation favors reducing energetically costly behaviors, and exploring novel environments may be just one of them.  相似文献   
104.
The levels of selected polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in human milk samples from the areas of Venice and Rome, primarily in order to characterize the current levels of infant exposure to PCBs and PBDEs due to breast feeding in Italy. Sixteen non-dioxin-like PCBs, including the traditional indicator congeners, and 11 PBDEs, comprising the relevant PBDE-47, PBDE-99, and PBDE-153, were determined. Congeners were selected for analysis according to their relative abundance in human tissues, toxicological relevance, and diffusion in the environment. Dietary habits of the milk donors were recorded by questionnaires; mothers of the Venice area were classified into three groups according to their consumption of local fish, molluscs, and other fishery products. Sigma(16)(PCBs) and Sigma(11)(PBDEs) (ng g(-1) fat) for the areas of Venice and Rome were respectively, 250-390 and 240, and 1.6-2.8 and 4.1. An increase of fish and fishery product consumption could not be associated with an increase of PCB and PBDE levels in milk.  相似文献   
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This article deals with wilderness politics in relationship to values and public participation; these terms are defined for the purpose of the study. It is argued that the survival, quantity, and quality of wilderness everywhere will basically be determined by the political and governmental processes through values. Yet there is a strong tendency in these processes to avoid value exposure and emphasis.Much of governmental approach toward wilderness affairs hinges upon economic development, technoscientific facts, and short-term considerations, in contrast to the intangible noneconomic and long-term values of wilderness. By not articulating nd involving wilderness values more in public participation and the political processes, the public often misses opportunities for influencing far-reaching wilderness decisions. In short, wilderness values need to be more explicitly and implicitly stated and implemented politically.More study and emphasis need to be given to wilderness values per se. It is necessary to develop more innovative ways of educating the public on wilderness values in terms of their lives and of ensuring that their value inputs are effectively incorporated into public participation and political processes. The last section of this article is devoted to efforts by the author and others to identify and describe wilderness tropical forest values.  相似文献   
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