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1.
Concentrations of platinum and lead were measured in common grass sampled near the Autobahn. Additionally, platinum was determined in spot checks of ash from seawage sludge incinerators to 1972. The increase in Pt levels since 1987 was traced back to releases from automobile catalytic converters. The emission rate of a car equipped with a catalytic converter has been estimated by comparison with Pb.  相似文献   
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Environmental and biological reef monitoring was conducted in Almirante Bay (Bahía Almirante) in Bocas del Toro, Panama, to assess impacts from anthropogenic developments. An integrated monitoring investigated how seasonal temperature stress, turbidity, eutrophication and physical impacts threatened reef health and biodiversity throughout the region. Environmental parameters such as total suspended solids [TSS], carbon isotopes (δ13C), C/N ratios, chlorophyll a, irradiance, secchi depth, size fractions of the sediments and isotope composition of dissolved inorganic carbon [DIC] of the water were measured throughout the years 2010 and 2011 and were analysed in order to identify different impact sources. Compared to data from Collin et al. (Smithsonian Contributions to the Marine Sciences 38:324–334, 2009) chlorophyll a has doubled at sites close to the city and the port Almirante (from 0.46–0.49 to 0.78–0.97 μg l?1) and suspension load increased, visible by a decrease in secchi depth values. Visibility decreased from 9-13 m down to 4 m at the bay inlet Boca del Drago, which is strongly exposed to river run off and dredging for the shipping traffic. Eutrophication and turbidity levels seemed to be the determining factor for the loss of hard coral diversity, most significant at chlorophyll a levels higher than 0.5 μg l?1 and TSS levels higher than 4.7 mg l?1. Hard coral cover within the bay has also declined, at some sites down to <10 % with extremely low diversities (7 hard coral species). The hard coral species Porites furcata dominated the reefs in highly impacted areas and showed a strong recovery after bleaching and a higher tolerance to turbidity and eutrophication compared to other hard coral species in the bay. Serious overfishing was detected in the region by a lack of adult and carnivorous fish species, such as grunts, snappers and groupers. Study sites less impacted by anthropogenic activities and/or those with local protection showed a higher hard coral cover and fish abundance; however, an overall loss of hard coral diversity was observed.  相似文献   
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The stock of the catadromous European eel (Anguilla anguilla L.) continues to decline and there is growing evidence that poor health status due to contaminants might be a key element in this decrease. Organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) belong to the major threats to yellow eel in their growth habitat and their metabolites are detectable in the bile. Starting the silvering process eels undergo physiological and morphological changes including cessation of feeding and downstream migration back to their spawning grounds. Reduced feed intake results in a diminishment of bile production and induces accumulation of e.g. PAH-metabolites in bile. Therefore, the aim of the present study was to demonstrate the impact of silvering on biliary PAH metabolite concentrations and to utilize normalization procedures to overcome silvering related accumulation effects of PAH-metabolites in eel bile. We investigated the hydroxyl-metabolites of pyrene (1-OH Pyr) and phenantrene (1-OH Phen) in the bile of different maturation stages of eels (silvering index I-V) from nine German rivers. We detected increasing absolute PAH metabolite levels in bile during the silvering process. The highest rise could be observed at the transition from pre migration stage III to the migrating stage IV, suggesting the onset of cessation of feeding at this stage. A cessation bias in PAH metabolite measurement could be diminished by normalization of absolute values against bile pigments (A380, biliverdin). In conclusion, we demonstrated the impact of silvering on PAH metabolite concentrations in eel bile and present suitable normalization procedures to overcome silvering related accumulation effects. Thus, for a future eel monitoring we recommend (1) to regularly monitor PAH metabolites in bile, (2) to determine silvering index of eel and (3) to normalize PAH metabolite values in bile based on maturation/silvering stages. The knowledge of the silvering stage is mandatory for an unbiased evaluation of PAH contamination of European eel towards an international harmonized eel monitoring program.  相似文献   
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ABSTRACT

Previously reported volatile organic compounds (VOC) radiocarbon (14C) measurements for 1992 summertime Atlanta, GA, have been compared with chromatographic data and emissions inventory predictions. The chromatographic approach that was used provided a more comprehensive VOC characterization than typically achieved, and the emissions inventory was research-grade level (date-, site-, and time-specific). The comparisons are in general agreement that biogenic emissions contribute only modestly (<10%) to the VOC content of the particular ambient samples that were collected and measured. The choices of sampling site (near city-center) and times (early morning and late evening) are major influences on the results, which consequently should not be regarded as representing the average VOC biogenic impact for the Atlanta area.  相似文献   
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In most bushcrickets, males transfer a large spermatophore during copulation that is afterwards consumed by the female. In some species this nuptial gift enhances offspring fitness and is therefore believed to function as paternal investment. To determine whether this is the case, I examined whether a male's own offspring benefit from spermatophore consumption in the bushcricket Poecilimon veluchianus. Females that consumed a spermatophore produced offspring with increased residuals of dry weight compared to females that were prevented from feeding on the spermatophore. This beneficial effect of spermatophore consumption occurred within the first 4 days after copulation. An increased dry weight indicates higher energy reserves because offspring dry weight correlates significantly with the lifespan of starved larvae and because spermatophore consumption increased the lifespan of starved offspring. During egg-laying, females apply a liquid substance to the soil that hardens and probably serves as protection for the egg clutch. The amount of this substance correlated with the number of eggs laid but did not differ between spermatophore treatments. In P. veluchianus, females mate frequently and there is last-male sperm precedence. The spermatophore thus only constitutes paternal investment when offspring produced before female remating benefit from spermatophore consumption. The dry weight of offspring increased during the first 4 days after spermatophore consumption and thus within the natural remating interval. This shows that the spermatophore has a paternal investment function in addition to its already known sperm protection function. Received: 15 May 1998 / Accepted after revision: 11 October 1998  相似文献   
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The data situation to chemical substances is unsatisfactory— in spite of in part considerable efforts in the last decades. One knows still very little on the subject of the dangerous characteristics of chemical substances. The consequences of this ignorance have primarily the employees to carry. They get sick due to a dealing with substances whose characteristics were not completely enlightened. But as well the enterprises have to suffer under it, after all, lose her experienced staff member and have to pay the costs about the Berufsgenossenschaften for these knowledge deficits. In the EU, the future European chemical policy is therefore discussed. The contribution explains the range of the sicknesses through dealing with substances with unknown characteristics.  相似文献   
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The European Union Guideline 2001/58/EG (safety data sheet guideline) states that the safety data sheet shall enable professional users to take the necessary measures for the protection of health and safety at the workplace as well as of the environment. According to this guideline, the employer should be in the position to determine whether hazardous chemical agents do exist at the workplace, and to assesses the risk to health and safety of workers arising from their use. Can the employer actually rely on the safety data sheet? Have the present data sheets really instructed how to safely handle and manage dangerous compounds? Are the numerously arising occupational illnesses by dangerous substances just a consequence of a careless handling? This question is also important in the discussion on REACH, the new European Chemicals Policy. This paper reveals the strengths and the weaknesses as well as the potential of manufacturer information.  相似文献   
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Despite political efforts, diffuse pollution from agriculture continues to be the single largest source of nitrogen (N) emissions into the aquatic environment in many countries and regions. This fact, and the recent enactment of a new Swedish environmental code, led to the design of a study targeted at the evaluation of new N pollution abatement strategies. An actor game was chosen as the key component of the study, with a focus on four major goals: to test the implementability of legally binding environmental quality standards for nitrate concentration in groundwater and N transport to the sea, to find sets of agriculturally feasible and cost-effective measures to decrease N loads, to investigate the possibilities for collective action through negotiated and institutionalized actor cooperation, and to investigate the role of mathematical modeling in environmental N management. Characteristics from the agriculturally dominated catchment of Genevads?n (224 km2) on the southwest coast of Sweden served as the playing field for the actor game. The most noteworthy result from the study was that it appeared to be possible to meet ambitious environmental N standards with less economically drastic measures than anticipated by most of the participants. The actor game was shown to be a good method for learning about the new Swedish environmental code and its application and for gaining deeper insight into the issues of N management. In addition, the actor game functioned as an arena for gaining a more thorough understanding of the views of different stakeholders.  相似文献   
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