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311.
The aim of the study was to investigate toxicity of bendiocarb (2, 3-isopropyledene-dioxyphenyl methylcarbamate) to organs of chicken embryo. The toxic action of bendiocarb was observed on liver and central nervous system (CNS). Bendiocarb was administered to chicken embryos at embryonic day (ED) 3 in a dose 500 μ g/egg and 10 ED (800 μ g/egg). The observations showed no macroscopic or microscopic changes in the liver and CNS with either dose or day of incubation when the bendiocarb was administered. The liver and CNS were also investigated for caspase activity in relation to application of bendiocarb and no differences in the number of cells with caspase immunopositivity were observed in comparison with the control. The results obtained indicate that bendiocarb administered in the respective doses showed no toxicity to investigated organs. Furthermore, both at the early (3 ED) and the later (10 ED) stages of development no increase in numbers of apoptotic cells in chicken embryos was observed.  相似文献   
312.
Human biomonitoring (HBM), defined as the measurement of concentrations of chemicals or of their metabolites in human biological matrices, is considered the method of choice for determining internal exposures in individuals. HBM is part of environmental exposure surveillance systems in several countries. In 2007, the Ministry of Agriculture, Food and Environment promoted BIOAMBIENT.ES project, a national-level HBM study on environmental pollutants carried out in Spain to estimate levels of heavy metals, persistent organic pollutants, and other substances on the Spanish active workforce. BIOAMBIENT.ES is a nationwide cross-sectional study, with a stratified cluster sampling designed to cover all geographical areas, sex and occupational sectors, and aimed to obtain a representative sample of the Spanish workforce. Participants were recruited among people residing in Spain for 5 years or more, which underwent their annual occupational medical check-up in the health facilities of the Societies for Prevention of IBERMUTUAMUR, MUTUALIA, MC-PREVENCIÓN, MUGATRA, UNIMAT PREVENCIÓN, and PREVIMAC (March 2009–July 2010). A total of 1,892 subjects fulfilled the criteria for inclusion, donated biological samples (1,880 blood, 1,770 urine, and 577 hair) and completed a short self-administrated epidemiological questionnaire on environmental and lifestyle-related exposures. Additionally, clinical information from participant’s health exams was obtained. This project will provide a first overview of the body burden of selected pollutants in a representative sample of the Spanish-occupied population. This information will be useful to establish reference values of the studied population and, eventually, to evaluate temporal trends and the effectiveness of environmental and health policies.  相似文献   
313.
Webster EM  Ellis DA 《Chemosphere》2012,87(4):404-412
Biotransformation is widely recognized as the most important and most uncertain determinant of bioaccumulation. A step-wise method for estimating organism-specific biotransformation half-lives from field observations and using established food web modeling is developed. As a proof of concept, the method is applied to the case of nine polycyclic aromatic hydrocarbons (PAHs) in a well-studied food web in Bohai Bay, China. The estimated half-lives are in good agreement with the existing literature. The proposed biotransformation estimation method, through data mining, for sufficiently defined ecosystems, may greatly reduce the necessary animal testing involved in chemical assessments by providing useful guidance to experimentalists and regulators.  相似文献   
314.
The quality of the sludge in Wastewater Treatment Plants (WWTPs) depends on the suitable colonization of the flocs by microorganisms. Due to the functional importance of these biological constituents, several biological or biological-related parameters have been commonly used for the control of depuration efficiency. According to national and international water regulation recommendations, interlaboratory studies have a great relevance to determine which parameters are more reliable for their extensive application in routine control. However, these studies are also very useful to demonstrate consistency in results from multiple laboratories and to develop reliable and reproducible methodologies which might be necessary for protocol validation and also for accreditation issues to meet regulatory environmental requirements. The main purpose of this work was to assess the results obtained in consecutive interlaboratory assays in order to determine the concordance degree in the application of biological parameters by participating laboratories. Following the international recommendations about these studies, a common working protocol was proposed. Statistical tests indicated that Sludge Index and several routine physical-chemical analyses [V30, Mixed Liquor Suspended Solids (MLSS), Mixed Liquor Volatile Solids (MLVS) and Sludge Volumetric Index (SVI)] show low variability and therefore are suitable tools for laboratory control. Shannon Index and Sludge Biotic Index also presented low variability although a more precise protocol would be necessary, in particular the methodology to count small flagellates. The abundance and identification of protist species showed low concordance among laboratories and three factors were responsible for the low reliability of data: population density, size and morphological distinguishable characters of the specimens.  相似文献   
315.
This paper illustrates a step-by-step approach for evaluating chemical monitoring data in air and deposition and for prioritizing chemicals to be included in long-term air monitoring programs. The usability of the method is shown by application to data generated within the Swedish screening program. The suggested prioritization approach uses a novel methodology by combining empirical data on occurrence in air and deposition with publicly available quantitative structure activity relationship estimation tools that predict atmospheric persistence and bioaccumulation. A selection tree is presented, which may be used by regulatory bodies to prioritize chemicals for long-term air monitoring. A final ranking list is presented proposing a prioritization order for inclusion in monitoring programs. Based on the suggested strategy, the chemicals identified as most relevant to include in Swedish long-term monitoring programs were short-chain chlorinated paraffins(C10-C13), perfluorooctane sulfonate, octachlorostyrene, hexabromocyclododecane, hexachlorobenzene, pentachloroanisole, decamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, pentachlorobenzene, 1,2,3,4-tetrachlorobenzene, hexachlorobutadiene, dodecamethylcyclohexasiloxane, perfluorodecane sulfonate, 1,2,4,5-tetrachlorobenzene, and pentabromophenol.  相似文献   
316.
In this work are presented results of the complex study of two significant solid environmental samples: gravitation dust sediments (industrial pollutants, potential source of risk elements input to soils) and soils (component of the environment, potential source of risk elements input to food web). The first phase of this study was focused on the study of the significant chemical properties (phase composition, content of organic and inorganic carbon) of the dust and soil samples. In the second phase, the fractionation analysis was used on the evaluation of the mobility of chosen risk elements (Cu, Ni, Pb, Zn) in the studied samples. The single-step extractions were applied in the order of the isolation of the element forms (fractions), with different mobilities during defined ecological conditions by utilization of the following reagents: 1 mol dm − 3 NH4NO3 for isolation of the “mobile” fraction, 0.05 mol dm − 3 ethylenediaminetetraacetic acid and 0.43 mol dm − 3 CH3COOH for isolation of the “mobilizable” fraction, and 2 mol dm − 3 HNO3 for isolation of all releasable forms. On the basis of the results obtained in this study, it is possible to state that different origins and positions of solid environmental samples in the environment reflect in different chemical properties of their matrix. The different properties of the sample matrix result in different mobilities of risk elements in these kinds of samples. The fractionation analysis with single-step extraction for isolation element fractions is the method most suitable for easy checking of environmental pollution and for evaluation of risk elements cycle in the environment.  相似文献   
317.
Different collector types, sample workup procedures and analysis methods to measure the deposition of polycyclic aromatic hydrocarbons (PAH) were tested and compared. Whilst sample workup and analysis methods did not influence the results of PAH deposition measurements, using different collector types changed the measured deposition rates of PAH significantly. The results obtained with a funnel-bottle collector showed the highest deposition rates and a low measurement uncertainty. The deposition rates obtained with the wet-only collectors were the lowest at industrial sites and under dry weather conditions. For the open-jar collectors the measurement uncertainty was high. Only at an industrial site with extremely high PAH deposition rates the results of open-jar collectors were comparable to those obtained with funnel-bottle collectors. Thus, if bulk deposition of PAH has to be measured, funnel-bottle combinations are proved to be the collectors of choice. These collectors were the only ones always fulfilling the requirements of European legislation.  相似文献   
318.
Fly ash and sewage sludge are suggested materials for constructing sealing layers covering mine tailings impoundments. Little is known, however, of their effect on vegetation or resistance to root penetration. We investigate: (i) the ability of different plant species to grow in sealing layers comprising fly ash and sewage sludge, (ii) the impact on plant growth of freshly hardened fly ash compared to aged and leached ash, and (iii) the plant stress response to fly ashes of different properties. A 6-mo greenhouse study using birch (Betula pendula Roth.), Scots pine (Pinus sylvestris L.), Kentucky bluegrass (Poa pratensis L.), and willow (Salix viminalis L.) demonstrated that no roots could grow into a compacted layer consisting only of ash, while a 6:4, ash-sludge mixture admitted roots into the upper part and a 1:9, ash-sludge mixture was totally penetrated (to 15 cm in depth) by roots of willow and Scots pine. Freshly hardened ash prevented root growth more effectively than aged ash did, as was observed in tests using reed canarygrass (Phalaris arundinacea L.) and pea (Pisum sativum L.). Furthermore, extracts of highly alkaline ash were more toxic to pea in a 48-h toxicity test than less alkaline ash was. However, stress responses to diluted ash extracts of lower pH, measured as enzyme capacities in dwarf bean (Phaseolus vulgaris L.), were more related to the metal and ion contents. Root penetration of sealing layers is most effectively prevented if little sewage sludge is added, and if ash of high alkalinity is chosen.  相似文献   
319.
The central objectives of the European Forum on Integrated Environmental Assessment (EFIEA) include improving the scientific quality of Integrated Environmental Assessments (IEA) as well as strengthening the interactions between science and policy making in environmental matters. This paper is intended to provide a concise assessment of the evolution of IEA methods and present it as a background to current thinking on and practice in IEA. Historical roots of IEA concepts and applications are explored. Common elements and distinctive features in recent proposals to define IEA are sorted and a liberal definition is proposed for the purposes of the present methodological study. This definition emphasizes the interdisciplinary character and environmental policy orientation of IEAs. Changes in the nature, social perception, and management of environmental problems are identified as the major factors driving methodological development in IEAs. A simple scheme is proposed to arrange the main elements of IEA: disciplinary tools, integration tools, and assessment frameworks. The role of IEAs in environmental management is examined by adopting the concept of risk management functions. Due to the varying needs for interdisciplinary research and diverging degrees of policy involvement across those functions, the potential contribution of IEAs to activities belonging to different functions also varies. The flexibility and diversity of IEAs are demonstrated by a sampler of frameworks that have been developed to address profoundly different problems and audiences. This revised version was published online in July 2006 with corrections to the Cover Date. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
320.
Summary. The odour perceptive abilities, and preferences, of three bark beetle parasitoid species; Rhopalicus tutela (Walker), Roptrocerus mirus (Walker), and Roptrocerus xylophagorum (Ratzeburg) (Hymenoptera: Pteromalidae), were investigated to isolate and identify the essential compounds involved in host location. These parasitoids attack several economically important bark beetle species and oviposit preferentially on late larval stages concealed under the bark of conifers. Odours were collected from Norway spruce logs (Picea abies L. Karst.) containing Ips typographus L. (Coleoptera: Scolytidae) larvae. Biologically active compounds were isolated by coupled gas chromatographic-electroantennographic detection (GC-EAD), and identified by GC-mass spectrometry (GC-MS). Based on these analyses, four different synthetic baits were prepared and tested in a Y-tube walking bioassay. In the complex odour samples from spruce logs, only 16 compounds were EAD-active. The tested R. tutela and R. mirus females displayed similar trends in antennal activity to EAD-active compounds, responding mainly to oxygenated monoterpenes that indicate damaged conifers. Consequently, the synthetic baits were exclusively prepared with oxygenated monoterpenes. Parasitoid females (R. tutela and R. mirus) preferred spruce logs containing susceptible hosts over fresh logs, while male parasitoids (R. mirus) did not show any preference. However, when odours from fresh logs were mixed with synthetic baits (mimicking the odour composition of logs containing susceptible hosts), these combinations attracted female parasitoids (R. tutela, R. mirus, and R. xylophagorum). All synthetic baits seemed to be equally attractive to female parasitoids. Received 12 October 2000; accepted 18 January 2001  相似文献   
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