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871.
Potential environmental effects of the discharge of industrial wastewater from manufacturing of bleached straw pulp have been studied. Bleached neutral sulphite straw pulping results in discharges of both black cooking and spent bleaching liquors. Time proportional samples were taken from the combined bleaching effluent and the combined mill effluent, (i) Mutagenic activity of the two samples in an Ames’ test, and (ii) acute toxicity of the combined mill effluent sample towards the photosynthetic activity of natural marine phytoplankton from the receiving waters were determined. Also, acute toxicity was determined of the slowly biodegradable or persistent organics remaining after aerobic stabilization of the sample towards (ii) photosynthetic activity of natural phytoplankton, (iii) mussels (Mytilus edulis), (iv) eels (Anguilla anguilla) and, (v) crustacean (Nitocra spinipes); and furthermore, (vi) reproduction test of the crustacean and (vii) growth inhibition test of the marine diatom (Phaeodactylum tricornutum) were performed. Mutagenicity emission factors (MEF's) and toxicity emission factors (TEF's) were calculated to classify the effluents. Combined mill effluent sample showed a mutagenic activity per t90 of one fourth the activity of a kraft pulp bleaching effluent, and the inhibition of the photosynthesis of natural phytoplankton was significant up to 2600 times dilution. After aerobic stabilization, inhibition was observed up to 400 times dilution. Other effects of the combined mill effluent sample were only significant below 40 times dilution. The bleaching effluent showed a mutagenic activity per t90 comparable to kraft bleaching effluents. Other effects were only significant below 20 times dilution.  相似文献   
872.
Hydrophobicity and bioaccumulation potential of linear and cyclic polydimethylsiloxane (PDMS) oligomers were estimated by reversed‐phase liquid chromatography and feeding experiments with guppies (Poecilia reticulata). PDMS concentrations in fish were determined by capillary column gas chromatography and gas chromatography‐mass spectrometry. In contrast to polychlorinated biphenyls (PCBs), only very small amounts of PDMS were retained by the fish after six weeks feeding.  相似文献   
873.
Two hundred ninety‐two mother's milk samples were collected during 1994 from ten Egyptian governorates representing rural, metropolitan, and newly reclaimed desert areas. The samples were analyzed for 14 organochlorine insecticides and metabolites using electron capture gas chromatography and confirmed by gas chromatography/mass spectrometry (GC/MS). The overall samples average showed that the most abundant organochlorine insecticide residues were p,p'‐DDE, α‐endosulfan, β‐HCH and, p,p’‐DDT. Residues in the range of not detectable to less than 14μg/l whole milk were recorded for α‐HCH, heptachlor, heptachlor epoxide, aldrin, dieldrin, endrin endrin aldehyde and p,p'‐DDD. The percentage of samples exceeding the acceptable daily intake for children (ADIs) set by the FAO/WHO ranged from 19% to 44% in all governorates included in the study except the governorate of Minia in which only 2.6% of the samples exceeded the ADI values. The insecticides exceeding ADI values are mostly heptachlor and heptaclor epoxide (ADI = 3.12 μg/1 whole milk).  相似文献   
874.
Thirty diet samples from three different social groups were collected both in summer and in winter seasons using duplicate portion technique with three collection days. Toxic element concentrations, including Pb, Cd, as well as some essential elements were determined by atomic absorption spectrometry (AAS). The average dietary intakes of Taiwanese were estimated as follows (means ± S.D., n = 30): Mg, 175 ± 77 mg/day; Zn, 9.5 ± 11.4 mg/day; Mn, 2.8 ± 1.3 mg/day; Cu, 1.6±1.7mg/day; Ni, 0.13 ± 0.14 mg/day; Cd, 58 ± 62 μg/day, and Pb, 31 ±26 μg/day. The obtained elemental concentrations were scattered due to different dietary habits and cooking methods. In addition, a strong correlation arose between the trace element concentrations in agricultural products and in the diet of regional areas of Taiwan. Analysis results indicated that average intakes are consistently below current US Recommended Daily Allowances (RDAs) for Mg and Zn, within the recommended safe and adequate RDA for Mn, and below the FAO/WHO Provisional Tolerable Daily Intakes (PTDIs) for Pb. The average daily intakes of Cd by regional area of Taiwan markedly exceeded those of other countries and the PTI value during the summer.  相似文献   
875.
The heavy metal content in sewage sludges from a big Chinese city was investigated. Concentrations of zinc (Zn), lead (Pb), copper (Cu), chromium (Cr), nickel (Ni), cadmium (Cd) and mercury (Hg) in the sludges were 258–4050 mg kg‐1, bd: 994 mgkg‐1, 8.3–566 mg kg‐1, 26.3–370mgkg‐1 4.2–113 mg kg‐1 0.9–6.4 mg kg‐1 and 1.8–12.4 mg kg‐1 respectively. The concentrations of Zn and Pb in the sewage sludges from the residential areas were higher than those in the mixed ones (from both residential and industrial areas). The concentrations of heavy metals in the flocculently dewatered sewage sludges were higher than those in the sediment of the centrifuged undewatered sewage sludges. After centrifuging, more than 60% of heavy metals remained in the sludge sediment with an exception of Cd. The content of organic matter, total phosphorus (T‐P) and total potassium (T‐K) in these sewage sludges was also measured.  相似文献   
876.
Airborne concentrations of PAH in the vicinity of the source region with open‐air burning of metal scraps were measured between February, 1992 and November, 1993. The activity of open‐air burning decreased significantly since 1993 due to prohibition regulation. Both gaseous phase and particle‐bound PAH were measured at five sampling sites, which included one reference sampling site far away from the source region. Both values of gaseous and particle‐bound PAH concentrations, which were measured in the vicinity of source region, decreased clearly during the two years monitoring period. It shows that the uncontrolled open‐air burning of metal scraps was a significant emission source of airborne PAH in the study area. The profiles of various species of PAH were also compared. A large decrease in benzo(a)pyrene was observed in the source region.  相似文献   
877.
Polychlorinated dibenzo‐p‐dioxins and dibenzofurans (PCDD/DFs) and coplanar polychlorinated biphenyls (Co‐PCBs) were determined in fly ash samples from municipal solid waste (MSW), medical waste (MW), and electricity power plant incinerators in Taiwan. The average concentrations of PCDD/DFs and Co‐PCBs are 7.02 ng‐TEQ/g and 1.06 ng‐TEQ/g, respectively. The contributions to total TEQ are 24% from PCDDs, 64% from PCDFs, and 12% from Co‐PCBs, indicating that PCDFs generate the highest environmental impact and MSW and MW incinerators are potential Co‐PCBs contaminating sources. The levels of PCDD/DFs and Co‐PCBs found in ash samples increase from petroleum‐fired, coal‐fired, large municipal solid waste, small medical waste, to small municipal solid waste incinerators, and are generally lower than those from incinerators built earlier. All fly ash samples analyzed in this study were considered hazardous materials. More research is suggested to establish the relationship between the amounts of PCDD/DFs and Co‐PCBs in fly ash and in flue gas.  相似文献   
878.
As is the case to date with respect to sustainability indicators, there is an enormous quantity of information available about their basic components (social, economic and environmental), but these are generally dealt with in a sectoral and fragmented manner, and the components have been analysed and approached in a more or less independent fashion. On the other hand, it is difficult to find indicators that encompass all the dimensions of sustainability. The topic chosen for this research is sustainability organised in a systematic fashion, which entails taking the combination of issues that affect each subsystem and investigating the states of territorial adjustment that exist between each of them. In short, it is the possibility of establishing a sustainable territorial development pattern, accepting that the economic and social activities that utilise the natural resources influence sustainability, and that they will do so to a greater or lesser extent depending on the effectiveness of the conservation of the stock of resources. The Territorial Adjustment Indicator System (TAIS) is a good tool that enables the management, assessment and monitoring of development processes in PNAs (protected natural areas), facilitating homogeneity and uniformity to aid comparison between protected areas in the centre-south of Spain, principally those areas designated as natural parks (NPs).  相似文献   
879.
Limited studies have shown that disaster risk management (DRM) can be cost‐efficient in a development context. Cost–benefit analysis (CBA) is an evaluation tool to analyse economic efficiency. This research introduces quantitative, stochastic CBA frameworks and applies them in case studies of flood and drought risk reduction in India and Pakistan, while also incorporating projected climate change impacts. DRM interventions are shown to be economically efficient, with integrated approaches more cost‐effective and robust than singular interventions. The paper highlights that CBA can be a useful tool if certain issues are considered properly, including: complexities in estimating risk; data dependency of results; negative effects of interventions; and distributional aspects. The design and process of CBA must take into account specific objectives, available information, resources, and the perceptions and needs of stakeholders as transparently as possible. Intervention design and uncertainties should be qualified through dialogue, indicating that process is as important as numerical results.  相似文献   
880.
In 2008, the International Federation of Red Cross and Red Crescent Societies (IFRC) used a seasonal forecast for West Africa for the first time to implement an Early Warning, Early Action strategy for enhanced flood preparedness and response. Interviews with disaster managers suggest that this approach improved their capacity and response. Relief supplies reached flood victims within days, as opposed to weeks in previous years, thereby preventing further loss of life, illness, and setbacks to livelihoods, as well as augmenting the efficiency of resource use. This case demonstrates the potential benefits to be realised from the use of medium‐to‐long‐range forecasts in disaster management, especially in the context of potential increases in extreme weather and climate‐related events due to climate variability and change. However, harnessing the full potential of these forecasts will require continued effort and collaboration among disaster managers, climate service providers, and major humanitarian donors.  相似文献   
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