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81.
The assessment of eco-toxicological impacts related to the emission of contaminants into the environment has peculiar characteristics in the context of Life Cycle Assessment (LCA), and many different Life Cycle Impact Assessment (LCIA) methodologies can be used. However, previous studies recognized the presence of high uncertainties in the process, in particular when the analysis focuses on metal emissions. Metals are diverse inorganic substances relevant for their characteristic environmental chemistry, their high persistency into the environment and their toxicity at even low environmental concentrations. This study aims at expanding the discussion about how, and how differently, various methods for LCIA are estimating the impacts related to metals emissions, with a focus on eco-toxicological impacts. A comparison between eight different LCIA methods is presented in relative terms, using a contribution analysis at two levels: general and specific. Results show that there is a poor agreement between methods in the determination of the total eco-toxic impact attributable to metals, and in defining which metal provokes the highest eco-toxic impact per unitary emission. Furthermore, the characterization phase is critical in determining the disagreement between methods. However, some similarities were found: there is the tendency in most methods to associate the largest share of the total eco-toxicological impacts to metals. Theoretical and practical differences between methods are discussed and suggestions for the choice of the proper, case-specific, LCIA method are provided.  相似文献   
82.
As the use of ultrasonography has become a routine procedure in the care of pregnant women, fetal congenital malformations have been frequently diagnosed prenatally. During a 4-year period abdominal wall defects (AWD) were diagnosed in 14 cases, five were gastroschises and nine were omphaloceles, seven females and seven males. Concomitant malformations were present in one case of gastroschisis and in five cases of omphalocele. Eleven AWD's were diagnosed in the second trimester and six pregnancies were interrupted. Eight children with AWD were born; two boys with omphalocele and one girl and one boy with gastroschisis are still alive. Alpha-fetoprotein was determined in amniotic fluid in 11 cases and also in maternal serum prior to the amniocentesis in eight cases. Chromosomal investigations were performed in 13 cases, 11 on amniotic fluid cells and two on lymphocytes from a blood sample made postnatally. Two abnormal karyotypes, 47,XX + 18 were found.  相似文献   
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The echolocation calls used by Nyctalus leisleri during search phase in open air space are between 9 and 14 ms long, with the peak energy between 24 and 28 kHz. The pulses are shallowly frequency-modulated with or without an initial steep frequency-modulated component. The diet consists primarily of small flies (Diptera), including many chironomids (wingspan 9–12 mm) and yellow dung flies (Scatophaga; wingspan 24 mm), but also of some larger insects such as dung beetles (Coleoptera; Scarabaeoidea), caddis-flies (Trichoptera) and moths (Lepidoptera). The echo target strength of some prey items was measured. Contrary to models based on standard targets such as spheres or disks, the echo strength of real insects was found to be virtually independent of the emitted frequency within the 20–100 kHz frequency range. A model was used to calculate probable detection distances of the prey by the bat. Using narrow-band calls of 13.7 ± 2.7 ms duration, a bat would detect the two smallest size classes of insect at greatest range using calls of 20 kHz. The results may therefore explain why many species of large and medium sized aerial-hawking bats use low-frequency calls and still eat mostly relatively small insects. The data and model challenges the assumption that small prey are unavailable to bats using low-frequency calls.  相似文献   
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Risk-based regulation assumes that risk assessment can evaluate risks against policy objectives. However, policy goals are often ambiguous and require risk assessors to interpret them for use in risk assessment. This risk assessment-policy gap stems partly from normative and imprecise policy language but is rooted more fundamentally in society's uncertain expectations for the environment. Until this uncertainty is resolved, the democratic and regulatory effectiveness of risk regulation will be undermined by ad hoc policy decisions abdicated to risk assessors.  相似文献   
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Modelling of environmental impacts from the application of treated organic municipal solid waste (MSW) in agriculture differs widely between different models for environmental assessment of waste systems. In this comparative study five models were examined concerning quantification and impact assessment of environmental effects from land application of treated organic MSW: DST (Decision Support Tool, USA), IWM (Integrated Waste Management, U.K.), THE IFEU PROJECT (Germany), ORWARE (ORganic WAste REsearch, Sweden) and EASEWASTE (Environmental Assessment of Solid Waste Systems and Technologies, Denmark). DST and IWM are life cycle inventory (LCI) models, thus not performing actual impact assessment. The DST model includes only one water emission (biological oxygen demand) from compost leaching in the results and IWM considers only air emissions from avoided production of commercial fertilizers. THE IFEU PROJECT, ORWARE and EASEWASTE are life cycle assessment (LCA) models containing more detailed land application modules. A case study estimating the environmental impacts from land application of 1 ton of composted source sorted organic household waste was performed to compare the results from the different models and investigate the origin of any difference in type or magnitude of the results. The contributions from the LCI models were limited and did not depend on waste composition or local agricultural conditions. The three LCA models use the same overall approach for quantifying the impacts of the system. However, due to slightly different assumptions, quantification methods and environmental impact assessment, the obtained results varied clearly between the models. Furthermore, local conditions (e.g. soil type, farm type, climate and legal regulation) and waste composition strongly influenced the results of the environmental assessment.  相似文献   
90.
Safety matters are boring, bothersome or just a cost factor. These are some of the arguments which prevent safety issues from being treated in the same way as, for example, transport logistics, i.e., rationally aiming at optimum results. National legal evolutions, resulting in distinct rules and regulations, are another handicap for a European approach to common marine safety standards. Political changes within the European Community offer a chance to create a marine safety system which complies with developments in shipping, operational practices, and requirements resulting from casualty investigations and statistics. The establishment of a European Marine Transport Safety Board under the umbrella of a European Transport Safety Board is proposed to mutually benefit from road, rail, air and sea transport knowledge.  相似文献   
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