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11.
High resolution gas chromatography (HRGC) coupled to quadrupole negative ion chemical ionization (NICI) mass spectrometry (MS) was used to investigate congener patterns, levels and enantiomer distribution of selected toxaphene congeners (#26, #41, #44, #50, #63, B7-1453) in human milk from Germany. #50 and #26 were the most abundant congeners. Furthermore, the identification of B7-1453, B8-1412, #41, #42, #44 and #63 was possible. Levels for the sum of #26, #41, #44 and #50 ranged from 7 to 24 microg kg(-1) milk fat and contributed between 2 and 9% to the total burden of investigated organochlorines such as selected compounds of the chlordane group, HCH, DDT and polychlorinated biphenyls (PCB). Capillaries coated with heptakis-(2,3,6-O-tert-butyldimethylsilyl)-beta-cyclodextrin (TBDMS-CD) or octakis-(2,3,6-tri-O-ethyl)-gamma-cyclodextrin (TEG-CD) were used for the enantioselective separations. Enantiomer ratios (ER) and enantiomer fractions (EF) of the abundant toxaphene congeners #26 and #50 as well as of B7-1453, #41 and #63 were determined. Greatest deviations from a racemic composition in individual human milk samples were found for #41 (1.54-2.37), #50 (1.37-1.72) and #63 (0.53-0.71) whereas ERs for #26 were close to 1. Compared to wildlife biota such as fish and raptors ER changes were more pronounced in human milk but comparable to human adipose tissue.  相似文献   
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The aim of this work was to make a comparison of indoor radon concentrations in dwellings and in soil air in the area of two geological formations in the Suwa?ki region (Poland). The mean arithmetic airborne concentration was found to be the highest (301 Bq m (-3)) in the basements of buildings in the gravel and sand areas, whereas in the boulder clay areas it reached 587 Bq m (-3). Out of 54 measurements of radon concentrations performed at the ground floor, in eight cases concentrations were found to exceed 200 Bq m (-3) - permissible radon level in new-built houses in Poland and in three cases these values were even higher than 400 Bq m (-3). The highest radon levels were noted in houses with earthen basement floors and with direct entrance from the basement to rooms or kitchens. The mean arithmetic radon concentration in the soil air in the sandy and gravel formations was 39.7 kBq m (-3) and in clay formation it was 26.5 kBq m (-3). Higher radon levels were also found in the water obtained from household wells reaching 8367 Bq m (-3) as compared with tap water (2690 Bqm (-3)). The mean indoor concentration for the whole area under study was found to be 169.4 Bq m (-3), which is higher than the mean value for Poland (49.1 Bq m (-3)) by a factor of 3.5.  相似文献   
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A method for the determination of 16 selected pharmaceuticals in surface water using LC-MS/MS has been developed Methods from literature were adapted within the scope of this study. The limit of quantification of 13 out of 16 analytes is below 10 ng/l. The analysis of samples from the Saale river and lakes around Halle demonstrated that Carbamacepin (Median 207 ng/l) and Diclofenac (Median 196 ng/l) are detectable at various sampling stations along the river. The wastewater path was identified as the most relevant source for pharmaceutical residues entering the environment. Besides, the results reveal increased levels of several substances in some smaller anabranches and brooks.  相似文献   
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The uptake and accumulation of the traffic-related platinum group elements (PGE) Pt, Pd and Rh by the aquatic fauna was investigated. Zebra mussels, eels and barbels were maintained in water containing either road dust or ground catalytic converter material. Following the exposure, samples of fish liver and kidney, as well as the soft tissues of the mussels, were analysed. Our results revealed that all three catalytic noble metals were accumulated by aquatic organisms. The highest bioavailability was found for Pd, followed by Pt and Rh. The concentration factor of Pd forDreissena polymorpha was 5 times higher compared with Pd and only 6 times lower than the essential element Cu. With regard to the increasing emission of Pd the level of this metal has to be monitored very carefully in the environment.  相似文献   
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At the Earth Summit in Johannesburg in 2002, partnerships were touted as one of the key routes to sustainable development. But can partnerships really deliver improvements to rural livelihoods? This paper reviews one set of claimed partnerships, those between forestry companies and local individuals or communities, to assess the benefits, and the costs, to local livelihoods. Most arrangements between forestry companies and local communities are not equitable enough to be called partnerships, so the term “deal” is preferred. Positive local impacts of company–community deals include sharing of risks, better returns to land than otherwise possible, opportunities for income diversification, access to paid employment, development of new skills, upgrading of local infrastructure and environmental improvement. However, company–community deals have not yet proved sufficient to lift people out of poverty. They remain supplementary rather than central to income generation. Furthermore, while some deals have resulted in greater cohesion and organisation among community groups, there is as yet little evidence of substantial increases in community bargaining power. Ways forward to increase returns to communities (and to their counterpart companies) centre on moving towards more equal partnerships, by raising community bargaining power, fostering the roles of brokers and other third parties, and developing equitable, efficient and accountable governance frameworks.  相似文献   
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Sweden introduced limits and gave recommendations for decreasing the indoor radon daughter concentrations in 1980. The resulting experiences are summarized. From 1979 to 1987, measurements were carried out by the local authorities in about 58 000 out of 3.9 million homes in Sweden, and 5300 homes were found to have levels exceeding the limit for existing houses, or 400 Bq/m3 of equilibrium equivalent concentration of radon (EER). This may be about 13% of the estimated 40 000 homes with levels exceeding 400 Bq/m3. Very high levels, up to 28 000 Bq/m3, have been found. According to the local authorities, in one third of the homes found with levels exceeding the limit (1921 homes) certain reconstruction and other measures have been taken in order to decrease the levels. In reality, measures have been carried out in more houses. The methods depend on the radon source. The average reductions found for respective methods are reported. The local authorities can require a check of the radon daughter concentrations in newly built houses when they suspect that the concentrations exceed the limit of 70 Bq/m3. In 11% of the measured homes built during 1981 to 1985, the levels were above the limit for newly built houses. In 1.4% of these houses, the limit for existing houses, 400 Bq/m3, had been exceeded. The strategy to decrease both the collective dose to the population and the individual dose is discussed.  相似文献   
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