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71.
Although Safety, Health and Environment (SHE) principles are adhered to in companies of developed countries, the application in developing countries is at its infant stage, as shown by the present article where the authors surveyed SHE Practice in 242 companies of 8 West-African countries.  相似文献   
72.
Large-scale studies are essential to assess the emission patterns and spatial distribution of organohalogenated pollutants (OHPs) in the environment. Bird eggs have several advantages compared to other environmental media which have previously been used to map the distribution of OHPs. In this study, large-scale geographical variation in the occurrence of OHPs, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), was investigated throughout Europe using eggs of a terrestrial residential passerine species, the great tit (Parus major). Great tit eggs from 22 sampling sites, involving urban, rural and remote areas, in 14 European countries were collected and analysed (5-8 eggs per sampling site). The environmentally most important congeners/compounds of the analysed pollutants were detectable in all sampling locations. For PCBs, PBDEs and OCPs, no clear geographical contamination pattern was found. Sum PCB levels ranged from 143 ng/g lipid weight (lw) to 3660 ng/g lw. As expected, PCB concentrations were significantly higher in the sampled urban compared to the remote locations. However, the urban locations did not show significantly higher concentrations compared to the rural locations. Sum PBDEs ranged from 4.0 ng/g lw to 136 ng/g lw. PBDEs were significantly higher in the urbanized sampling locations compared to the other locations. The significant, positive correlation between PCB and PBDE concentrations suggests similar spatial exposure and/or mechanisms of accumulation. Significantly higher levels of OCPs (sum OCPs ranging from 191 ng/g lw to 7830 ng/g lw) were detected in rural sampling locations. Contamination profiles of PCBs, PBDEs and OCPs differed also among the sampling locations, which may be due to local usage and contamination sources. The higher variance among sampling locations for the PCBs and OCPs, suggests that local contamination sources are more important for the PCBs and OCPs compared to the PBDEs. To our knowledge, this is the first study in which bird eggs were used as a monitoring tool for OHPs on such a large geographical scale.  相似文献   
73.
In this paper, I provide some evidence for the view that a common charge against those who adopt vegetarianism is that they would be sentimental. I argue that this charge is pressed frequently by those who adopt moral absolutism, a position that I reject, before exploring the question if vegetarianism might make sense. I discuss three concerns that might motivate those who adopt vegetarian diets, including a concern with the human health and environmental costs of some alternative diets, a concern about inflicting pain on animals, and a concern with the killing of animals. While I argue that vegetarianism does not make sense in some situations, I hope that this paper shows that there are many good reasons why the adoption of vegetarian, and—even more so—vegan diets might be appropriate in some situations. In carving out this position, I focus primarily on the question whether a morally relevant distinction between the killing of plants and the killing of animals should be made. I engage primarily with the views of two of the most prominent authors on this issue, arguing that neither Peter Singer nor Tom Regan provide a satisfactory account on the ethics of killing nonhuman organisms. Two views are challenged in particular, the view that relatively simple animals such as molluscs, as well as plants, lack awareness, and the view that animals without a preference to continue living stand to lose little or nothing by being killed. I provide some evidence to support the claim that many share my view that it is more problematic to kill animals than to kill plants, before analyzing why some suppress the negative feelings they associate with killing animals. By exploring these issues I hope to shed some light on the issue of whether the feelings of those who adopt vegetarianism are sentimental or make sense, and to stimulate reflection amongst those with an interest in food ethics.  相似文献   
74.
This study investigates the possibility of capturing CO2 from flue gas under pressurised conditions, which could prove to be beneficial in comparison to working under atmospheric conditions. Simulations of two hybrid combined cycles with pressurised fluidised bed combustion and CO2 capture are presented. CO2 is captured from pressurised flue gas by means of chemical absorption after the boiler but before expansion. The results show a CO2 capture penalty of approximately 8 percentage points (including 90% CO2 capture rate and compression to 110 bar), which makes the efficiency for the best performing cycle 43.9%. It is 5.2 percentage points higher than the most probable alternative, i.e. using a natural gas fired combined cycle and a pulverised coal fired condensing plant separately with the same fuel split ratio. The largest part of the penalty is associated with the lower mass flow of flue gas after CO2 capture, which leads to a decrease in work output in the expander and potential for feed water heating. The penalty caused by the regeneration of absorbent is quite low, since the high pressure permits the use of potassium carbonate, which requires less regeneration heat than for example the more commonly proposed monoethanolamine. Although the efficiencies of the cycles look promising it will be important to perform a cost estimate to be able to make a fair comparison with other systems. Such a cost estimate has not been done in this study. A significant drawback of these hybrid cycles in that respect is the complex nature of the systems that will have a negative effect on the economy.  相似文献   
75.
Greening flood protection (GFP) is increasingly recognized as an adaptive and flexible approach to water management that is well suited to addressing uncertain futures associated with climate change. In the last decade, GFP knowledge and policies have developed rapidly, but implementation has been less successful and has run into numerous barriers. In this paper, we address the challenge of realizing green flood protection goals by specifically considering knowledge in the decision-making of a Dutch flood protection project in Lake Markermeer. In this project, an ecological knowledge arrangement and a traditional flood protection knowledge arrangement are compared and their interactions analysed. The analysis provides insight into the specific difficulties of implementing GFP measures and identifies ways to realize GFP goals. The primary challenge is twofold: First, a self-reinforcing cycle of knowledge production and decision-making in the flood protection domain inhibits the introduction of innovative and multifunctional approaches such as GFP; second, the distribution of power is severely unbalanced in terms of ecological enhancement and flood protection, favouring the latter. Implementation of GFP requires structural change and the integration of ecological and flood protection knowledge and policy. Potentially rewarding routes towards this integration are the exploration of shared interests in GFP and the creation of mutual dependency between knowledge arrangements. The case study and the insights it provides show that GFP is far from mainstream practice and that implementation requires serious effort and courage to break with historical practices.  相似文献   
76.
Local emissions of Arctic air pollutants and their impacts on climate, ecosystems and health are poorly understood. Future increases due to Arctic warming or economic drivers may put additional pressures on the fragile Arctic environment already affected by mid-latitude air pollution. Aircraft data were collected, for the first time, downwind of shipping and petroleum extraction facilities in the European Arctic. Data analysis reveals discrepancies compared to commonly used emission inventories, highlighting missing emissions (e.g. drilling rigs) and the intermittent nature of certain emissions (e.g. flaring, shipping). Present-day shipping/petroleum extraction emissions already appear to be impacting pollutant (ozone, aerosols) levels along the Norwegian coast and are estimated to cool and warm the Arctic climate, respectively. Future increases in shipping may lead to short-term (long-term) warming (cooling) due to reduced sulphur (CO2) emissions, and be detrimental to regional air quality (ozone). Further quantification of local Arctic emission impacts is needed.  相似文献   
77.
Raptors are good sentinels of environmental contamination and there is good capability for raptor biomonitoring in Europe. Raptor biomonitoring can benefit from natural history museums (NHMs), environmental specimen banks (ESBs) and other collections (e.g. specialist raptor specimen collections). Europe’s NHMs, ESBs and other collections hold large numbers of raptor specimens and samples, covering long periods of time. These collections are potentially a valuable resource for contaminant studies over time and space. There are strong needs to monitor contaminants in the environment to support EU and national chemical management. However, data on raptor specimens in NHMs, ESBs and other collections are dispersed, few are digitised, and they are thus not easy to access. Specimen coverage is patchy in terms of species, space and time. Contaminant research with raptors would be facilitated by creating a framework to link relevant collections, digitising all collections, developing a searchable meta-database covering all existing collections, making them more visible and accessible for contaminant research. This would also help identify gaps in coverage and stimulate specimen collection to fill gaps in support of prioritised contaminant monitoring. Collections can further support raptor biomonitoring by making samples available for analysis on request.  相似文献   
78.
Bioaccumulation models take various elimination and uptake processes into account, estimating rates from chemical lipophilicity, expressed as the octanol-water partition ratio (Kow). Here, we focussed on metabolism, which transforms parent compounds into usually more polar metabolites, thus enhancing elimination. The aim of this study was to quantify the change in lipophilicity of relevant organic pollutants undergoing various biotransformation reactions in mammals. We considered oxidation reactions catalyzed by three enzyme groups: cytochrome P450 (CYP), alcohol dehydrogenase (ADH), and aldehyde dehydrogenase (ALDH). Estimated log Kow values of a selected dataset of parent compounds were compared with the log Kow of their first metabolites. The log Kow decreased by a factor that varies between 0 and −2, depending on the metabolic pathway. For reactions mediated by CYP, the decrease in Kow was one order of magnitude for hydroxylated and epoxidated compounds and two orders of magnitude for dihydroxylated and sulphoxidated xenobiotics. On the other hand, no significant change in lipophilicity was observed for compounds N-hydroxylated by CYP and for alcohols and aldehydes metabolized by ADH and ALDH. These trends could be anticipated by the calculus method of log Kow. Yet, they were validated using experimental log Kow values, when available. These relationships estimate the extent to which the elimination of pollutants is increased by biotransformation. Thus, the quantification of the Kow reduction can be considered as a first necessary step in an alternative approach to anticipate biotransformation rates, which are hard to estimate with existing methods.  相似文献   
79.
Perfluorinated compounds (PFCs), such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), are used in large quantities. They are persistent and found in measurable levels in human serum around the world. They have been associated with developmental, hepatic, and carcinogenic effects in animal studies. The aim of the present study was to describe levels of PFCs in serum among Inuits from Greenland and inhabitants from Warsaw, Poland and Kharkiv, Ukraine. Furthermore, the aim was to define social- and lifestyle related determinants of exposure for these compounds. Serum levels of seven PFCs were analyzed by liquid chromatography/tandem mass spectrometry (LC/MS/MS). The concentrations of PFOS and PFOA were the highest of all PFCs in all three populations with a total amount of almost 90% of the PFCs. The mean levels of PFOS and PFOA were in the Greenlandic Inuits 52 and 4.8 ng mL(-1), in Poland 19 and 5.2 ng mL(-1), and in Ukraine 8.1 and 1.9 ng mL(-1), respectively. Thus, levels of PFCs in the serum of Inuits on Greenland were among the highest described in a general population whereas the levels in Poland were similar to other industrialized countries. The exposure in Ukraine was rather low. In the Greenlandic Inuit population, intake of seafood, tea, age and area of living were significant determinants of PFOS concentrations and explained about 22% of the variation. For the other populations no strong determinants were found.  相似文献   
80.
Nanoscale zero-valent iron (nZVI) has recently gained great interest in the scientific community as in situ reagent for installation of permeable reactive barriers in aquifer systems, since nZVI is highly reactive with chlorinated compounds and may render them to harmless substances. However, nZVI has a high tendency to agglomerate and sediment; therefore it shows very limited transport ranges. One new approach to overcome the limited transport of nZVI in porous media is using a suited carrier colloid. In this study we tested mobility of a carbon colloid supported nZVI particle “Carbo-Iron Colloids” (CIC) with a mean size of 0.63 μm in a column experiment of 40 cm length and an experiment in a two-dimensional (2D) aquifer test system with dimensions of 110?×?40?×?5 cm. Results show a breakthrough maximum of 82 % of the input concentration in the column experiment and 58 % in the 2D-aquifer test system. Detected residuals in porous media suggest a strong particle deposition in the first centimeters and few depositions in the porous media in the further travel path. Overall, this suggests a high mobility in porous media which might be a significant enhancement compared to bare or polyanionic stabilized nZVI.  相似文献   
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