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Consumer demand for environmentally and socially responsible products is the driving force behind the expansion of competing certification systems. Paradoxically, this has led to an increasingly crowded marketplace for labels and confusion among stakeholders such as producers, retailers and buyers, rather than providing clear and reliable product information as intended. The situation has sparked a debate about the future of certification schemes and the need for a more streamlined system. This article explores some of the innovative ideas coming from the current discussion regarding biofuel certification and standardisation and outlines how those ideas can be applied to create a global generic standard-setting scheme for natural resources. 相似文献
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In recent years, many electronic manufacturing firms have looked upon Cleaner Production (CP) as the means by which they could maintain environmental practice and competitive advantages. CP has been adopted by companies as an important factor in enhancing industrial productivity. Sustainable projects that deal appropriately with environmental and social factors are also more likely to be the most profitable.This paper investigated the criteria and attributes that determine a successful adoption and implementation of CP in reference to PWB manufacture in Taiwan. Fuzzy Analytic Hierarchy Process (FAHP) methodology is used to discuss the different decision criteria that include Organizing, Systems and Technologies, Measurement and Feedback, Working environment and Worker's Culture which are all vital factors in an effective CP implementation. AHP is an efficient tool in controlling the fuzziness of the data involved in choosing the most preferred decision variables. The linguistic level of comparisons produced by the manufacturers and experts are tapped and constructed in a form of triangular fuzzy numbers in order to construct fuzzy pairwise comparison matrices. The implementation of the system is demonstrated by a problem involving three stages of hierarchy which contains different criteria and attributes at a wider perspective within an environmental uncertainty. The findings advocate that these enterprises would need to setup the priorities of the CP implementation. The results suggest a generic hierarchical model of organizations of which the highest level is to be prioritized among the CP implementation factors. 相似文献
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Background, aim, and scope Compared to other micropollutants such as pesticides or pharmaceuticals, less attention has been paid to biocides so far. A prioritisation of the biocides currently used in Switzerland in terms of pollution of waters revealed that quaternary ammonium compounds (QAC), the isothiazolinones chloromethylisothiazolinone and benzisothiazolinone as well as Irgarol exhibit the highest risk potential. The QAC benzalkoniumchloride (BAC) and didecyldimethylammoniumchloride (DDAC-C10) are used in considerable amounts and have a high biological activity. Materials and methods The emissions of selected QAC in waters and soil and the predicted environmental concentrations (PECs) were estimated by means of a substance flow analysis (SFA). The study was based on data from the Swiss products register, on literature, contacts to producers and users as well as on own assumptions. Results and discussion The consumption of BAC (four homologues) and DDAC-C10 in biocidal applications in Switzerland amounts to 90 and 30 tons annually. The most important applications are disinfectants for public health areas, food and feed areas as well as wood preservatives. The total emissions to the environment of all five substances account for approximately 11?t/a. The PECs in surface waters and sediments vary from values slightly lower than the predicted no-effect concentration (PNEC) to roughly three orders of magnitude below the PNEC. However, concentrations above the PNEC are possible at certain locations, particularly downstream of wastewater treatment plants (WWTP) effluents and sewer overflows. Effects on aquatic organisms can therefore not be excluded. Three BAC homologues could not be assessed, as there were no PNEC values available. Conclusions The contribution of emissions from WWTP (punctual emissions) to the environment is only about one tenth and relatively low compared to diffuse emissions. This means that measures for the emission reduction focussing only on end-of-pipe solutions in WWTP will not reduce the emissions significantly. Moreover, for the evaluation of measures, attention has to be paid to the fact that biocides such as the selected QAC are often also applied in non-biocidal applications (e.?g. three times higher volumes in the case of BAC). Recommendations and perspectives SFA serves as a useful tool for early recognition of environmental problems caused by chemicals. This allows recommending appropriate risk reduction measures in the production, the use and the end-of-life phase. It is advisable to use the SFA already in the development stage of chemicals and later on as a quality control tool. The relevant sources of chemicals and sinks in the environment can thus be determined in complex systems, even in absence of extensive measurements or product registers with consumption figures by means of estimations and scenarios. 相似文献
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Contamination of aquatic ecosystems with heavy metals has been receiving increased worldwide attention due to their harmful e ectson human health and other organisms in the environment. Most of the studies dealing with toxic e ects of metals deal with singlemetal species, while the aquatic organisms are typically exposed to mixtures of metals. Hence, in order to provide data supportingthe usefulness of freshwater fish as indicators of heavy metal pollution, it has been proposed in the present study to investigate thebioaccumulation and depuration of chromium in the selected organs of freshwater fingerlings Cirrhinus mrigala, individually and inbinary solutions with nickel. The results show that the kidney is a target organ for chromium accumulation, which implies that it is alsothe “critical” organ for toxic symptoms. The results further show that accumulation of nickel in all the tissues of C. mrigala is higherthan that of chromium. In addition, the metal accumulations of the binary mixtures of chromium and nickel are substantially higherthan those of the individual metals, indicating synergistic interactions between the two metals. Theoretically the simplest explanationfor an additive joint action of toxicants in a mixture is that they act in a qualitatively similar way. The observed data suggest that C.mrigala could be suitable monitoring organisms to study the bioavailability of water-bound metals in freshwater habitats. 相似文献
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Ivan Kourtchev Iustinian Bejan John R. Sodeau John C. Wenger 《Atmospheric environment (Oxford, England : 1994)》2009,43(20):3182-3190
The gas-phase ozonolysis of (E)-β-farnesene was investigated in a 3.91 m3 atmospheric simulation chamber at 296 ± 2 K and relative humidity of around 0.1%. The relative rate method was used to determine the reaction rate coefficient of (4.01 ± 0.17) × 10?16 cm3 molecule?1 s?1, where the indicated errors are two least-squares standard deviations and do not include uncertainties in the rate coefficients for the reference compounds (γ-terpinene, cis-cyclooctene and 1,5-cyclooctadiene). Gas phase carbonyl products were collected using a denuder sampling technique and analyzed with GC/MS following derivatization with O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA). The reaction products detected were acetone, 4-oxopentanal, methylglyoxal, 4-methylenehex-5-enal, 6-methylhept-5-en-2-one, and (E)-4-methyl-8-methylenedeca-4,9-dienal. A detailed mechanism for the gas-phase ozonolysis of (E)-β-farnesene is proposed, which accounts for all of the products observed in this study. The results of this work indicate that the atmospheric reaction of (E)-β-farnesene with ozone has a lifetime of around 1 h and is another possible source of the ubiquitous carbonyls, acetone, 4-oxopentanal and 6-methylhept-5-en-2-one in the atmosphere. 相似文献
250.
Susan Hodgson Fu-Meng Khaw Mark S. Pearce Tanja Pless-Mulloli 《Atmospheric environment (Oxford, England : 1994)》2009,43(21):3356-3363
BackgroundIn the UK air quality has been monitored systematically since 1914, providing valuable data for studies of the long-term trends in air pollution and potentially for studies of health effects of air pollutants. There are, however, challenges in interpreting these data due to changes over time in the number and location of monitored sites, and in monitoring techniques. Particulate matter was measured as deposited matter (DM) using deposit gauge monitors until the 1950s when black smoke (BS) filters were introduced. Estimating long-term exposure to particulates using data from both deposit gauge and BS monitors requires an understanding of the relationships between DM, SO2 and BS.AimsTo explore whether DM and/or SO2, along with seasonal and location specific variables can be used to predict BS levels.MethodsAir quality data were abstracted from hard copies of the monthly Atmospheric Pollution Bulletins for the period April 1956–March 1961 for any sites with co-located DM, SO2 and BS data for three or more consecutive years. The relationships between DM, SO2, and BS were assessed using mixed models.ResultsThere were 34 eligible sites giving 1521 triplets of data. There was a consistent correlation between SO2 and BS at all sites, but the association between DM and BS was less clear and varied by location. Mixed modelling allowing for repeat measurements at each site revealed that SO2, year, rainfall and season of measurement explained 72% of the variability in BS levels.ConclusionsSO2 can be used as a surrogate measure for BS in all monitoring locations. This surrogate can be improved upon by consideration of site specific characteristics, seasonal effects, rainfall and year of measurement. These findings will help in estimating historic, long-term exposure to particulates where BS or other measures are not available. 相似文献