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The European Union Guideline 2001/58/EG (safety data sheet guideline) states that the safety data sheet shall enable professional users to take the necessary measures for the protection of health and safety at the workplace as well as of the environment. According to this guideline, the employer should be in the position to determine whether hazardous chemical agents do exist at the workplace, and to assesses the risk to health and safety of workers arising from their use. Can the employer actually rely on the safety data sheet? Have the present data sheets really instructed how to safely handle and manage dangerous compounds? Are the numerously arising occupational illnesses by dangerous substances just a consequence of a careless handling? This question is also important in the discussion on REACH, the new European Chemicals Policy. This paper reveals the strengths and the weaknesses as well as the potential of manufacturer information.  相似文献   
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Engineering projects involving hydrogeology are faced with uncertainties because the earth is heterogeneous, and typical data sets are fragmented and disparate. In theory, predictions provided by computer simulations using calibrated models constrained by geological boundaries provide answers to support management decisions, and geostatistical methods quantify safety margins. In practice, current methods are limited by the data types and models that can be included, computational demands, or simplifying assumptions. Data Fusion Modeling (DFM) removes many of the limitations and is capable of providing data integration and model calibration with quantified uncertainty for a variety of hydrological, geological, and geophysical data types and models. The benefits of DFM for waste management, water supply, and geotechnical applications are savings in time and cost through the ability to produce visual models that fill in missing data and predictive numerical models to aid management optimization. DFM has the ability to update field-scale models in real time using PC or workstation systems and is ideally suited for parallel processing implementation. DFM is a spatial state estimation and system identification methodology that uses three sources of information: measured data, physical laws, and statistical models for uncertainty in spatial heterogeneities. What is new in DFM is the solution of the causality problem in the data assimilation Kalman filter methods to achieve computational practicality. The Kalman filter is generalized by introducing information filter methods due to Bierman coupled with a Markov random field representation for spatial variation. A Bayesian penalty function is implemented with Gauss–Newton methods. This leads to a computational problem similar to numerical simulation of the partial differential equations (PDEs) of groundwater. In fact, extensions of PDE solver ideas to break down computations over space form the computational heart of DFM. State estimates and uncertainties can be computed for heterogeneous hydraulic conductivity fields in multiple geological layers from the usually sparse hydraulic conductivity data and the often more plentiful head data. Further, a system identification theory has been derived based on statistical likelihood principles. A maximum likelihood theory is provided to estimate statistical parameters such as Markov model parameters that determine the geostatistical variogram. Field-scale application of DFM at the DOE Savannah River Site is presented and compared with manual calibration. DFM calibration runs converge in less than 1 h on a Pentium Pro PC for a 3D model with more than 15,000 nodes. Run time is approximately linear with the number of nodes. Furthermore, conditional simulation is used to quantify the statistical variability in model predictions such as contaminant breakthrough curves.  相似文献   
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A high impact polystyrene (HIPS) plastic, flame retarded with decabromodiphenyl ether (DecaBDE) and antimony trioxide (Sb2O3) has been repeatedly processed and the amount of debromination of the flame retardant and possible formation of PBDD/F was monitored. No indications of debromination were found. The reprocessed (recycled) plastic was found to comply with the German Chemicals Banning Ordinance. The concentrations of relevant PBDD/F congeners were at least one order of magnitude below the regulated limit values for PBDD/F (1 ppb for the sum of four congeners, 5 ppb for the sum of all eight regulated congeners).  相似文献   
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Field observations and manipulative experiments in a nearshore cobble bed (2 to 3 m below mean low water) at Eagle Head, Nova Scotia, Canada, between 1984 and 1986, showed that small juveniles ofStrongylocentrotus droebachiensis (3 to 6 mm diam) sheltering beneath cobbles had a refuge from predators such as rock crabs, small lobsters, and fish. Sea urchins gradually outgrew these refuges and small adults (25 to 30 mm) required larger rocks as shelter from predators, particularly large cancrid crabs. Small juveniles were usually solitary and well dispersed beneath cobbles, whereas small adults tended to aggregate on the undersides and in the interstices of boulders. These aggregations may develop passively as sea urchins accumulate in suitablysized refuges. Chemotaxis experiments indicate that juvenileS. droebachiensis are repelled by waterborne stimuli from conspecifics. In a factorial experiment, effects of the presence of potential predators (rock crabs and lobsters) and/or food (kelp) on the behaviour of large juvenile (10 to 15 mm) and small adult sea urchins were examined in flowing seawater tanks. Both size classes formed exposed feeding aggregations when kelp was provided as food, irrespective of the presence or absence of predators. In the absence of kelp, each size class responded differently to the presence of a predator: juveniles became more cryptic, whereas adults aggregated on the tank sides. Increased movement to the sides of a tank in the presence of a predator may reflect a flight response, since chemotaxis experiments indicated thatS. droebachiensis is repelled by waterborne chemical stimuli from predators. Observational and experimental data suggest that predation at the late juvenile and early adult stages may influence population structure, distribution and abundance ofS. droebachiensis.  相似文献   
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Political decision-makers in the European Union (EU) are currently discussing the introduction of a mandatory uniform labelling scheme for meat and milk that provides information on husbandry systems similar to the already existent labelling scheme in the EU egg market. The objective of this paper was to assess whether such information is relevant to consumers when buying meat and milk. The paper was based on a systematic synthesis of 53 scientific journal articles on empirical consumer studies. The review revealed that consumers perceived the aspects of outdoor access, stocking density and floor type as important factors influencing animal welfare. On average, consumers not only had a positive attitude towards more animal welfare-friendly husbandry systems with outdoor access and space allowance but were also willing to pay a price premium for products from such systems. All studies on consumer segmentation identified at least one consumer segment that placed great importance on animal welfare-friendly husbandry systems. Interestingly, many studies identified one or more other segments who still had a significant preference for animal welfare-friendly products even though other product attributes were more important to them. Based on the findings, the paper presents conclusions regarding the labelling of husbandry systems for meat and milk.  相似文献   
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Chen CY  Hamm JT  Hass JR  Albro PW  Birnbaum LS 《Chemosphere》2002,46(9-10):1501-1504
Pregnant Long Evans rats received 1.0 μg/kg of dioxin toxic equivalents (TEQ) by oral gavage on the 15th gestational day (GD 15), using a dosing mixture that contained two polychlorinated dioxins, four polychlorinated furans and three non-ortho polychlorinated biphenyls (PCBs). Rats were sacrificed on GD 16, GD 21 and postnatal day 4 (PND 4). The lipid content of fetus, pup, placenta and maternal liver, serum and adipose tissue were determined. Treated GD 16 and GD 21 fetuses had identical lipid content to the control group, yet the lipid content of treated pups on PND 4 was 32% higher than that of the control group. On the other hand, the lipid content of placenta, liver, and serum from the treated dams was 44–50%, 24%, and 38% lower than that of the control group, respectively. Thus, a low-dose mixture of dioxin-like compounds can cause changes in lipid content. The lipid content of offspring was not affected until they were exposed via lactation.  相似文献   
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