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231.
Perfluorinated Surfactants in Surface and Drinking Waters (9 pp)   总被引:1,自引:0,他引:1  
Background, Aim and Scope In this paper recent results are provided of an investigation on the discovery of 12 perfluorinated surfactants (PS) in different surface and drinking waters (Skutlarek et al. 2006 a, Skutlarek et al. 2006 b). In the last years, many studies have reported ubiquitous distribution of this group of perfluorinated chemicals, especially perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in the environment, particularly in wildlife animal and human samples (Giesy and Kannan 2001, Houde et al. 2006, Prevedouros et al. 2006). Perfluorinated surfactants (e.g. PFOS and PFOA) have shown different potentials for reproductory interference and carcinogenity in animal experiments as well as partly long half-lives in humans (Guruge et al. 2006, FSA UK 2006a, FSA UK 2006b, 3M 2005, OECD 2002, Yao and Zhong 2005). They possess compound-dependent extreme recalcitrance against microbiological and chemical degradation and, in addition, they show variable potentials for bioaccumulation in animals and humans (Houde et al. 2006). Materials and Methods: Surface and drinking water samples were collected from different sampling sites: - Surface waters: samples taken from the rivers Rhine, Ruhr, Moehne and some of their tributaries. Further samples were taken from the Rhine-Herne-Canal and the Wesel-Datteln-Canal. - Drinking waters: samples taken in public buildings of the Rhine-Ruhr area. After sample clean-up and concentration by solid-phase extraction, the perfluorinated surfactants were determined using HPLC-MS/MS. Results: All measured concentrations (sum of seven mainly detected components) in the Rhine river and its main tributaries (mouths) were determined below 100 ng/L. The Ruhr river (tributary of the Rhine) showed the highest concentration (94 ng/L), but with a completely different pattern of components (PFOA as major component), as compared with the other tributaries and the Rhine river. Further investigations along the Ruhr river showed remarkably high concentrations of PS in the upper reaches of the Ruhr river and the Moehne river (tributary of the Ruhr) (Ruhr: up to 446 ng/L, Moehne: up to 4385 ng/L). The maximum concentration of all drinking water samples taken in the Rhine-Ruhr area was determined at 598 ng/L with the major component PFOA (519 ng/L). Discussion: The surface water contaminations most likely stem from contaminated inorganic and organic waste materials (so-called 'Abfallgemisch'). This waste material was legally applied to several agricultural areas on the upper reaches of the Moehne. Perfluorinated surfactants could be detected in some suchlike soil samples. They contaminated the river and the reservoir belonging to it, likely by superficial run-off over several months or probably years. Downstream, dilution effects are held responsible for decreasing concentrations of PS in surface waters of the Moehne and the Ruhr river. In analogy to the surface water samples, PS (major component PFOA) can be determined in many drinking water samples of the Rhine-Ruhr area where the water supplies are mainly based on bank filtration and artificial recharge. Conclusions: The concentrations found in drinking waters decreased with the concentrations of the corresponding raw water samples along the flow direction of the Ruhr river (from east to west) and were not significantly different from surface water concentrations. This indicates that perfluorinated surfactants are at present not successfully removed by water treatment steps. Recommendations and Perspectives: Because of their different problematic properties (persistence, mobility, toxicity, bioaccumulation), the concentrations of specific perfluorinated surfactants and their precursors in drinking waters and food have to be minimised. Therefore, it is of utmost importance to take the initiative to establish suitable legal regulations (limitations/ban) concerning the production and use of these surfactants and their precursors. Furthermore, it is indispensable to protect water resources from these compounds. A discussion on appropriate limit values in drinking water and foodstuffs is urgently needed. Concerning the assumed soil contamination, the corresponding regulation (Bioabfall-Verordnung 1998 – Regulation on Organic Waste 1998) should be extended to allow the control of relevant organic pollutants.  相似文献   
232.
Environmental Science and Pollution Research - The average nutrient concentrations values presented in Table 1 on page 4 in the publication have the unit mg L?1 for the mineral nutrients Fe,...  相似文献   
233.
234.
Voluntary and active participation by a wide variety of actors is a prerequisite for successful societal transitions towards sustainability. The ‘Commitment to Sustainable Development 2050’ is a national-level initiative in Finland, aiming to mobilise a large-scale transition involving various societal actors through openly communicated commitments to concrete actions. Each commitment should focus on at least one of the eight nationally defined sustainability objectives connected to the global Sustainable Development Goals. This article assesses the implementation and the development needs of the commitment process based on a range of materials. The results highlight the importance of securing adequate resources for long-term coordination and continuous development of the commitment process, trust creation through long-term and open communication, and flexibility allowing for experimentation aimed at finding new modes of interaction between the public and private sectors.  相似文献   
235.
The aim of this contribution was the ecological characterization of 32 selected terrestrial Central-European enchytraeid species regarding factors of land use, pH-value, grain-size distribution, humus form, and soil moisture. The background of this characterization is generated by the so-called Soil Biological Site-Classification (abbreviated BBSK), a concept for the soil-biological assessment of soils. The crucial point within this concept is the comparison of the theoretically expected soil biocoenosis with the biocoenosis actually detected at a single site. Intending to obtain a simplified management of the parameters mentioned, these were each divided into three to five classes. The data-basis for the ecological characterization was formed by analysing suitable sources of literature with both biological and abiotic data given for one site. The result of the analysis was the frequency of a single species regarding the classes of the viewed soil parameters. On the basis of these results, the enchytraeid coenosis of three adjacent Bavarian sites of different use was predicted exemplarily and the enchytraeid community of these sites was investigated. The comparison of the predicted and detected coenoses showed that the sureness of the forecast varied between the different land uses: for wood and grassland, the prognosis was very precise and satisfactory, whereas the forecast for the agricultural site differed quite extensively. This was mainly due to the narrow data basis for agricultural sites.  相似文献   
236.
237.
M. Gilek  M. Björk  C. Näf 《Marine Biology》1996,125(3):499-510
The present study was designed to examine the influence of body size on the bioaccumulation of polychlorinated biphenyl (PCB) congeners by Baltic Sea blue mussels, Mytilus edulis L. This was done, firstly, by establishing the relationship (as a power function: PCB tissue conc = a tissue dry wtb) between tissue concentration and body weight for seven PCB congeners (International Union of Pure and Applied Chemistry No. 52, 101, 105, 118, 138, 153, and 180) in field sampled mussels; and, secondly, by assessing the influence of body weight on the uptake clearance coefficients, the depuration rate coefficients and the calculated bioaccumulation factors (BAFs) of three 14C-labelled PCB congeners (IUPAC No. 31, 49, 153) in mechanistic kinetic experiments. Both the background tissue concentrations of PCB 138, PCB 153 and PCB 180 and the predicted BAF values in the kinetic experiments correlated negatively with body weight (b=-0.17 and-0.31, respectively). Of the two kinetic rate coefficients examined, only the uptake clearance rate showed weight dependency (b=-0.32, i.e. negative correlation with body weight), whereas depuration rates were unaffectd by body weight. Uptake clearance rates and BAFs adjusted for body weight increased with the octanol/water partition coefficient (Kow) of the congener, whereas depuration rates dectreased with Kow. These observations suggest that size-dependent bioaccumulation of hydrophobic organic contaminants (HOCs) in suspension-feeding bivalves is driven by size-related differences in uptake rate, although several other mechanisms may also affect bioaccumulation in natural mussel beds (e.g. sizerelated differences in lipid content, production, and contaminant exposure). From an ecotoxicological perspective size-dependent bioaccumulation implies not only that variability due to body size differences has to be dealt with in experimental designs, but also that several ecological factors such as size-specific predation and shifts in population structure may affect HOC cycling by dense populations of bivalve suspensionfeeders.  相似文献   
238.
Mate sampling behaviour of black grouse females (Tetrao tetrix)   总被引:2,自引:0,他引:2  
We studied female mate sampling behaviour in lekking black grouse (Tetrao tetrix). Females mainly visited males occupying territories in the centre of the lek with relatively large territories. They were also more likely to visit males that had high attendance. The same factors were also correlated with male mating success. A multiple regression model including these factors explained more of the variance in female visits per male (53%) than in mating success (33%). The pattern of female sampling conformed with a pool comparison (best-of-n) tactic. Such a tactic is expected if the costs of sampling are low. Females of high body mass visited more males than lighter females, however, which indicates that females may vary in their search tactics and suggests that there may be search costs. The existence of costs is further suggested by the fact that if the mate from a previous year was still present, females always mated with the same male in the following year. Though search costs were not measured directly, our findings suggest that some costs are negligible (e.g. energetic exhaustion or predation) whereas others (timing of mating) may be more important.  相似文献   
239.
Contents and distribution of platinum-group-elements (PGE) in soils caused by automobile emissions were investigated at three transects perpendicular to the road at various depths. Concentrations of platinum, rhodium and palladium were determined by ICP-MS after separation and preconcentration by nickel-sulphide fire-assay. Platinum contents in roadside soils range from 250 μg/kg to the local background values which are below 0.5–0.8 μg/kg. Ratios of platinum and rhodium (about 6∶1) are similar to the ratios in catalytic converters. There is evidence for a significant correlation of PGE input and local parameters such as traffic-conditions, distance from the trafficlane, prevailing wind direction, and barriers such as vegetation or morphology.  相似文献   
240.
The occurrence and genetic effects of polyandry were studied in the ant Proformica longiseta using three microsatellite markers. The average queen mating frequency (QMF) estimated from the sperm dissected from the spermathecae of 61 queens was 2.4 with 69% of the queens being multiply mated. QMF estimated from worker offspring in a subsample of eight monogynous colonies was 3.5, but the effective paternity (me,p) was only 1.23. The difference between these values reflected unequal sperm use by the queens. Most colonies of P. longiseta were polygynous and the average relatedness among workers was 0.35. Polyandry thus added only marginally to the genetic diversity of colonies, and our results gave little support to the genetic-variability hypothesis for explaining polyandry. Diploid male load was low, as only 1% of males were diploid. A large majority (92%) of nests produced one sex only, with males produced in colonies that had higher than average worker relatedness. This contradicted the predictions derived from worker control of sex ratios. Males produced enough sperm to fill the spermathecae of several queens. Thus, the results indicated that diploid male load, sperm limitation and sex ratio conflict are also unlikely explanations of polyandry. Plausible hypotheses for polyandry include mating by convenience, as the sex ratio is male biased and the mating costs to a female can be low because the females are wingless and have no mating flight. The observed unequal sperm use furthermore points to sperm choice and sperm competition as important factors in the evolution of polyandry.  相似文献   
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