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31.
The River Po is the main Italian river draining one of the most populated and industrialised regions in Italy. As part of a monitoring project to assess environmental quality in the River Po, we measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in bottom sediments collected along the whole course of the river, from the spring to the delta, downstream from the confluence of its main tributaries. The aim was to investigate the level of contamination in the main Italian river and the contribution of contaminant loads from the subbasins. Composite sediment samples were collected in summer and winter surveys in low-flow water conditions and analysed by HRGC-HRMS for PCDD and PCDF homologue groups and for the 2,3,7,8-substituted congeners. The spatial trend observed in the Po River for PCDD and PCDF concentrations varied depending on the load of contaminants received from the tributaries and the processes of sedimentation. The sum of PCDD and PCDF concentrations, and the toxic equivalent content, ranged from 121 to 814 and from 1.3 to 13 ng/kg dry weight sediment, respectively. These levels of contamination seem lower than in the sediments of rivers draining highly industrialised areas. The PCDD and PCDF homologue profiles in all the samples were very similar, suggesting a common source of this contamination in the River Po. Principal component analysis suggested that widespread sources, such as urban runoff and domestic wastewaters, are probably the main cause of these levels of PCDDs and PCDFs.  相似文献   
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ABSTRACT

The emission inventory of the city of Santiago, Chile, related to mobile sources was built up using constant emission factors extracted from international literature. To improve the estimate of mobile source emissions, an experimental program was designed, consisting of transient tests on a chassis dynamometer over a sample of about 166 vehicles, applying 9 local driving cycles with average speeds of 3-80 km/hr, and experimentally determined in previous research carried out by the authors. An analysis of the influence of fuel inlet technology, and a year time-length model over emissions, was undertaken. We proposed emission factors as a function of average speed and of CO, THC, and NOx for catalytic and noncatalytic light-duty gasoline vehicles, disaggregated on commercial and private cars. A comparative analysis with emission factors obtained for the application of the COPERT II and AP-42 models was also presented. Our current analysis gives solid evidence indicating that to obtain a reasonable accuracy on emission estimates and calculations, local emission factors must be used.  相似文献   
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Abstract

The São Paulo Metropolitan area (SPMA) is characterized as having one of the worst air pollution problems in Brazil,with frequent violations of air quality standards for particulate matter. This paper presents the results of a eceptor model source apportionment study carried out to develop a quantitative database on which a control strategy could be developed. The study was conducted in four sites with distinct land uses. Fine, coarse (CP), and total suspended particles (TSP) samples were collected on Teflon and glass filters and analyzed by x-ray fluorescence XRF), ion chromatography, and thermal evolution. The sources were characterized by similar methodology. Chemical mass balance (CMB) receptor modeling indicated that carbonaceous material plays an important role in the aerosol composition; that the three major source categories contributing to the fine particles are vehicles, secondary carbon, and sulfates; and that the main contributors to CP and TSP are road dust and vehicles. All sampling sites presented the same general pattern in terms of source contribution, although this contribution varied from site to site.  相似文献   
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A compost isolated humic acid-like (cHAL) material was pointed out in previous work for its potential as auxiliary in chemical technology. Its potential is based on its relatively low 0.4gL(-1) critical micellar concentration (cmc) in water, which enables cHAL to enhance the water solubility of hydrophobic substances, like phenanthrene, when used at higher concentrations than 0.4gL(-1). This material could be obtained from a 1:1 v/v mixture of municipal solid and lignocellulosic wastes composted for 15 days. The compost, containing 69.3% volatile solids, 39.6% total organic C and 21C/N ratio, was extracted for 24h at 65 degrees C under N2 with aqueous 0.1molL(-1) NaOH and 0.1molL(-1) Na4P2O7, and the solution was acidified to separate the precipitated cHAL in 12% yield from soluble carbohydrates and other humic and non-humic substances. In this work two typical applications of surfactants, i.e., textile dyeing (TD) and soil remediation by washing (SW), were chosen as grounds for testing the performance of the cHAL biosurfactant against the one of sodium dodecylsulfate (SDS), which is a well established commercial synthetic surfactant. The TD trials were carried out with nylon 6 microfiber and a water insoluble dye, while the SW tests were performed with two soils contaminated by polycyclic aromatic hydrocarbons (PAH) for several decades. Performances were rated in the TD experiments based on the fabric colour intensity (DeltaE) and uniformity (sigmaDeltaE), and in the SW experiments based on the total hydrocarbons concentration (CWPAH) and on the residual surfactant (Cre) concentrations in the washing solution equilibrated with the contaminated soils. The results show that both cHAL and SDS exhibit enhanced performance when applied above their cmc values. However, while in the TD case a significant performance effect was observed at the surfactants cmc value, in the SW case the required surfactants concentration values were equivalent to 25-125xcmc for cHAL and to 4-22xcmc for SDS. The vis-a-vis comparison of the two surfactants gave the following results: in the TD case the cHAL biosurfactant at 0.4gL(-1) yields good colour intensity and equal colour uniformity as SDS at 5gL(-1), in the SW case cHAL was found to enhance CWPAH by a factor of 2-4 relative to SDS with one soil, whereas with the other soil the two surfactants behaved similarly. The Cre data, however, showed that both soils absorbed by far more SDS (68-95%) than cHAL (12-54%). The results point out intriguing technological and environmental perspectives deriving from the use of compost isolated biosurfactants in the place of synthetic surfactants.  相似文献   
36.
As a result of increasing global awareness about the importance of the environment, depletion of natural resources and legal pressures for companies to manage their processes in a sustainable manner, ISO 14001 systems have been gaining increasingly more importance in the organizational scenario. These elements are even more critical in emerging nations due to less awareness and fewer demands by governments and the population in relation to environmental issues. Therefore, the main objective of this study is to verify the benefits and difficulties of Environmental Management Systems based on ISO 14001 at industries in the state of São Paulo – Brazil (an emerging country) by conducting a survey to subsidize the proposal for actions in the public, academic and private sectors to promote the use of this standard of reference and strengthen its results in Brazil. A questionnaire was sent to 194 companies from the National Institute of Metrology, Standardization and Industrial Quality database. 69 answered, representing a return rate of 35.36%. The main benefits identified are related to the development of preventive environmental actions, reduction in the consumption of power, water, gas and fuel oil, and a positive influence on other internal management processes. The main difficulties are related to cost increases from ISO 14001 management systems and the constant changes in environmental legislation in Brazil. Some actions are proposed at the end of the analyses to intensify the use and improve the results of this standard, such as changes in government legislation and its collective development and implementation in industries.  相似文献   
37.
Among the Sustainable Development Goals (SDGs), the proposed SDG 15 promotes activities that, inter alia, “Protect, restore and promote sustainable use of terrestrial ecosystems”. An important potential contribution in achieving SDG 15 is through public programmes designed to jointly promote human development through poverty alleviation and improvement of human livelihoods and biodiversity conservation/management/restoration. An analysis of twenty public programmes with such joint objectives yielded twelve lessons learned. In addition to financial commitments, government and intergovernmental agency input for such public programmes includes ensuring political will and appropriate legal frameworks. Local communities and civil society provide input through traditional and indigenous ecological knowledge and stewardship. Appropriate shared inputs in development and the implementation of such public programmes, with communication between local community, broader civil society, the scientific community and governments will result in: better use and management of biodiversity; alleviation of poverty; security of livelihoods and better governance systems. The Ecosystem Approach of the Convention on Biological Diversity provides an ideal framework when planning and implementing new programmes. Application of the lessons learned to new public programmes will ensure that the answer to the question posed in the title is an emphatic “Yes”, and assist with the achievement of SDG 15.  相似文献   
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Federal and state environmental agencies conduct several programs to characterize the environmental condition of Chesapeake Bay. These programs use different benthic indices and survey designs, and have produced assessments that differ in the estimate of the extent of benthic community degradation in Chesapeake Bay. Provided that the survey designs are unbiased, differences may exist in the ability of these indices to identify environmental degradation. In this study we compared the results of three indices calculated on the same data, and the assessments of two programs: the Chesapeake Bay Program and the Mid-Atlantic Integrated Assessment (MAIA). We examined the level of agreement of index results using site-based measures of agreement, evaluated sampling designs and statistical estimation methods, and tested for significant differences in assessments. Comparison of ratings of individual sites was done within separate categories of water and sediment quality to identify which indices summarize best pollution problems in Chesapeake Bay. The use of different benthic indices by these programs produced assessments that differed significantly in the estimate of degradation. A larger fraction of poor sites was classified as good by the Environmental Monitoring and Assessment Program’s Virginian Province and MAIA benthic indices compared to the Chesapeake Bay benthic index of biotic integrity, although overall classification efficiencies were similar for all indices. Differences in survey design also contributed to differences in assessments. The relative difference between the indices remained the same when they were applied to an independent dataset, suggesting that the indices can be calibrated to produce consistent results.  相似文献   
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