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Microbiological risk assessment (MRA) has been evolving at the national and international levels as a systematic and objective approach for evaluating information pertaining to microbiological hazards in foods and the risks they pose. This process has been catalyzed by international food trade requirements to base sanitary measures on sound scientific evidence and appropriate risk assessments. All countries, including developing countries, need to understand and use MRA. MRA is resource intensive, as has been demonstrated by some of the the assessments undertaken in industrialized countries. However, when used in the appropriate circumstances MRA offers many benefits. The process of undertaking MRA improves the understanding of key issues, enables an objective evaluation of risk management options, and provides a scientific justification for actions. Although the gap between developing countries and some industrialized countries is quite extensive with regard to MRA, many developing countries recognize the need to at least understand and move toward using MRA. This process requires development of infrastructure and enhancement of scientific and technical expertise while making optimal use of limited resources. International organizations, such as the Food and Agriculture Organization of the United Nations, are in a position to provide countries with guidance, training, information resources, and technical assistance to develop and/or strengthen food safety infrastructure. Enhanced cooperation and collaboration at all levels are needed for such efforts to be successful and to ensure that MRA, as a food safety tool, is available to all countries.  相似文献   

3.
Life cycle assessment for sustainable metropolitan water systems planning   总被引:9,自引:0,他引:9  
Life Cycle Assessment (LCA) is useful as an information tool for the examination of alternative future scenarios for strategic planning. Developing a life cycle assessment for a large water and wastewater system involves making methodological decisions about the level of detail which is retained through different stages of the process. In this article we discuss a methodology tailored to strategic planning needs which retains a high degree of model segmentation in order to enhance modeling of a large, complex system. This is illustrated by a case study of Sydney Water, which is Australia's largest water service provider. A prospective LCA was carried out to examine the potential environmental impacts of Sydney Water's total operations in the year 2021. To our knowledge this is the first study to create an LCA model of an integrated water and wastewater system with this degree of complexity. A "base case" system model was constructed to represent current operating assets as augmented and upgraded to 2021. The base case results provided a basis for the comparison of alternative future scenarios and for conclusions to be drawn regarding potential environmental improvements. The scenarios can be roughly classified in two categories: (1) options which improve the environmental performance across all impact categories and (2) options which improve one indicator and worsen others. Overall environmental improvements are achieved in all categories by the scenarios examining increased demand management, energy efficiency, energy generation, and additional energy recovery from biosolids. The scenarios which examined desalination of seawater and the upgrades of major coastal sewage treatment plants to secondary and tertiary treatment produced an improvement in one environmental indicator but deteriorations in all the other impact categories, indicating the environmental tradeoffs within the system. The desalination scenario produced a significant increase in greenhouse gas emissions due to coal-fired electricity generation for a small increase in water supply. Assessment of a greenfield scenario incorporating water demand management, on-site treatment, local irrigation, and centralized biosolids treatment indicates significant environmental improvements are possible relative to the assessment of a conventional system of corresponding scale.  相似文献   

4.
This study presents the life cycle assessment (LCA) of three batteries for plug-in hybrid and full performance battery electric vehicles. A transparent life cycle inventory (LCI) was compiled in a component-wise manner for nickel metal hydride (NiMH), nickel cobalt manganese lithium-ion (NCM), and iron phosphate lithium-ion (LFP) batteries. The battery systems were investigated with a functional unit based on energy storage, and environmental impacts were analyzed using midpoint indicators. On a per-storage basis, the NiMH technology was found to have the highest environmental impact, followed by NCM and then LFP, for all categories considered except ozone depletion potential. We found higher life cycle global warming emissions than have been previously reported. Detailed contribution and structural path analyses allowed for the identification of the different processes and value-chains most directly responsible for these emissions. This article contributes a public and detailed inventory, which can be easily be adapted to any powertrain, along with readily usable environmental performance assessments.  相似文献   

5.
A life cycle assessment has been done to compare the potential environmental impacts of various gasoline blends that meet octane and vapor pressure specifications. The main blending components of alkylate, cracked gasoline, and reformate have different octane and vapor pressure values as well as different potential environmental impacts. Because the octane and vapor pressure values are nonlinearly related to impacts, the results of this study show that some blends are better for the environment than others. To determine blending component compositions, simulations of a reformer were done at various operating conditions. The reformate products of these simulations had a wide range of octane values and potential environmental impacts. Results of the study indicate that for low-octane gasoline (95 Research Octane Number), lower reformer temperatures and pressures generally decrease the potential environmental impacts. However, different results are obtained for high-octane gasoline (98 RON), where increasing reformer temperatures and pressures increase the reformate octane values faster than the potential environmental impacts. The higher octane values for reformate allow blends to have less reformate, and therefore high-octane gasoline can have lower potential environmental impacts when the reformer is operated at higher temperatures and pressures. In the blends studied, reformate and cracked gasoline have the highest total impacts, of which photochemical ozone creation is the largest contributor (assuming all impact categories are equally weighted). Alkylate has a much lower total potential environmental impact but does have higher impact values for human toxicity by ingestion, aquatic toxicity, terrestrial toxicity, and acidification. Therefore, depending on environmental priorities, different gasoline blends and operating conditions should be chosen to meet octane and vapor pressure specifications.  相似文献   

6.
对苏州某造纸企业新旧两条废水处理工艺的生命周期环境影响进行了对比研究。研究范围划定为:污水处理设施的建设阶段、运行阶段、污水处理设施的拆除阶段,通过统一的功能单位计算整理得到两条不同废水处理工艺的清单数据表。采用日本的AIST-LCAVer4评价软件进行影响评价,最终求得单一的生态指标:生态化的币值Yen。研究结果表明:上超滤前和上超滤后两套处理工艺的生态化币值分别为1.40Yen和1.15Yen,可见上超滤后对环境的影响比上超滤前的影响要小,其中药品对环境影响最大的为PAC的生产及使用。两套废水处理装置单项污染物排放量所占份额最大的是CO2,但上超滤后比上超滤前CO2的排放量下降了一半多,由原先的45.5kg/t纸降到21.9kg/t纸。造纸废水治理工艺的主要环境影响为城市空气污染、全球变暖、固体废弃物和资源消耗。我们认为,所获得的结论较为客观地反映了两种造纸废水治理工艺对环境的影响,可以作为中国造纸废水治理决策的参考依据。  相似文献   

7.
The sector of protective textiles was one of the European Lead Market Initiatives launched in 2012. As a result seven research and development projects were financed to support new and innovative products to enter to this market to increase safety at work. Also the legislation within Europe has a tendency towards this aim having higher impact on professional than on private clothing. If it is not possible to decrease the risks of a work place, the employer shall provide personal protective equipment (PPE), of which protective clothing is an essential part. In order to facilitate the choice, use and control of PPE, a large amount of EN standards and technical reports have been developed and published including requirements, classifications, test methods to be used, terminology and SUCAM. However, in the selection criteria, the environmental impact related with the production, use and disposal of different materials available in the market. In order to overcome this limitation within the SAFEPROTEX project, environmental impact of three different uniforms was evaluated using Life Cycle Analysis in comparison to reference garments.  相似文献   

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Food safety has become an important food quality attribute. Both food industry and authorities need to be able to trace back and to authenticate food products and raw materials used for food production to comply with legislation and to meet the food safety and food quality requirements.PaniGest is a user-friendly computer package designed to manage traceability and help in the quality control and production improvement. This application was developed in Visual Basic language over an SQL database and its main features are: to register quality control parameters of raw materials, in-course products and final products; to manage reception, production and expedition orders; to analyse production costs, productivity, raw materials and products’ consumptions; to trace products during the food chain. It runs on a personal computer over Windows 95/98 or Windows 2000/XP operating system. The program also uses common Internet Browsers to make information available to users.  相似文献   

10.
Prospective environmental life cycle assessment of nanosilver T-shirts   总被引:1,自引:0,他引:1  
A cradle-to-grave life cycle assessment (LCA) is performed to compare nanosilver T-shirts with conventional T-shirts with and without biocidal treatment. For nanosilver production and textile incorporation, we investigate two processes: flame spray pyrolysis (FSP) and plasma polymerization with silver co-sputtering (PlaSpu). Prospective environmental impacts due to increased nanosilver T-shirt commercialization are estimated with six scenarios. Results show significant differences in environmental burdens between nanoparticle production technologies: The "cradle-to-gate" climate footprint of the production of a nanosilver T-shirt is 2.70 kg of CO(2)-equiv (FSP) and 7.67-166 kg of CO(2)-equiv (PlaSpu, varying maturity stages). Production of conventional T-shirts with and without the biocide triclosan has emissions of 2.55 kg of CO(2)-equiv (contribution from triclosan insignificant). Consumer behavior considerably affects the environmental impacts during the use phase. Lower washing frequencies can compensate for the increased climate footprint of FSP nanosilver T-shirt production. The toxic releases from washing and disposal in the life cycle of T-shirts appear to be of minor relevance. By contrast, the production phase may be rather significant due to toxic silver emissions at the mining site if high silver quantities are required.  相似文献   

11.
The electrically conductive adhesives (ECA) are on the verge of a breakthrough as reliable interconnection materials for electronic components. As the ban of lead (Pb) in the electronics industry becomes a reality, the ECA's could be attractive overall alternatives to high melting point (HMP) Pb-based solder pastes. Environmental life cycle assessment (LCA) was used to estimate trade-offs between the energy use and the potential toxicity of two future types of ECA's and one HMP Pb-based. The probability is around 90% that the overall CO2 emissions from an ECA based on a tin-bismuth alloy are lower than for a silver-epoxy based ECA, whereas the probability is about 80% that the cumulative energy demand would be lower. It is more uncertain whether the tin-bismuth ECA would contribute to less CO2, or consume less energy, than a HMP Pb-based solder paste. Moreover, for the impact categories contributing to the life-cycle impact assessment method based on end point modeling (LIME) damage category of human health, the tin-bismuth ECA shows a 25 times lower score, and a silver-epoxy based ECA shows an 11 times lower score than the HMP Pb-based solder paste. In order to save resources and decrease CO2 emissions it is recommended to increase the collection and recycling of printed board assemblies using silver-epoxy based ECA.  相似文献   

12.
We examine the possibilities for a "greener" car that would use less material and fuel, be less polluting, and would have a well-managed end-of-life. Light-duty vehicles are fundamental to our economy and will continue to be for the indefinite future. Any redesign to make these vehicles greener requires consumer acceptance. Consumer desires for large, powerful vehicles have been the major stumbling block in achieving a "green car". The other major barrier is inherent contradictions among social goals such as fuel economy, safety, low emissions of pollutants, and low emissions of greenhouse gases, which has led to conflicting regulations such as emissions regulations blocking sales of direct injection diesels in California, which would save fuel. In evaluating fuel/vehicle options with the potential to improve the greenness of cars [diesel (direct injection) and ethanol in internal combustion engines, battery-powered, gasoline hybrid electric, and hydrogen fuel cells], we find no option dominates the others on all dimensions. The principles of green design developed by Anastas and Zimmerman (Environ. Sci. Technol. 2003, 37, 94A-101A) and the use of a life cycle approach provide insights on the key sustainability issues associated with the various options.  相似文献   

13.
Cement production is an environmentally relevant process responsible for 5% of total anthropogenic carbon dioxide emissions and 7% of industrial fuel use. In this study, life cycle assessment is used to evaluate improvement potentials in the cement production process in Europe and the USA. With a current fuel substitution rate of 18% in Europe and 11% in the USA, both regions have a substantial potential to reduce greenhouse gas emissions and save virgin resources by further increasing the coprocessing of waste fuels. Upgrading production technology would be particularly effective in the USA where many kiln systems with very low energy efficiency are still in operation. Using best available technology and a thermal substitution rate of 50% for fuels, greenhouse gas emissions could be reduced by 9% for Europe and 18% for the USA per tonne of cement. Since clinker production is the dominant pollution producing step in cement production, the substitution of clinker with mineral components such as ground granulated blast furnace slag or fly ash is an efficient measure to reduce the environmental impact. Blended cements exhibit substantially lower environmental footprints than Portland cement, even if the substitutes feature lower grindability and require additional drying and large transport distances. The highest savings in CO(2) emissions and resource consumption are achieved with a combination of measures in clinker production and cement blending.  相似文献   

14.
We developed a process-based model to predict the probability of arsenic exceeding 5 microg/L in drinking water wells in New England bedrock aquifers. The model is being used for exposure assessment in an epidemiologic study of bladder cancer. One important study hypothesis that may explain increased bladder cancer risk is elevated concentrations of inorganic arsenic in drinking water. In eastern New England, 20-30% of private wells exceed the arsenic drinking water standard of 10 micrograms per liter. Our predictive model significantly improves the understanding of factors associated with arsenic contamination in New England. Specific rock types, high arsenic concentrations in stream sediments, geochemical factors related to areas of Pleistocene marine inundation and proximity to intrusive granitic plutons, and hydrologic and landscape variables relating to groundwater residence time increase the probability of arsenic occurrence in groundwater. Previous studies suggest that arsenic in bedrock groundwater may be partly from past arsenical pesticide use. Variables representing historic agricultural inputs do not improve the model, indicating that this source does not significantly contribute to current arsenic concentrations. Due to the complexity of the fractured bedrock aquifers in the region, well depth and related variables also are not significant predictors.  相似文献   

15.
高忠柏 《中国皮革》2004,33(19):1-2
通过中国皮革工业的发展进程和环境状况 ,提出了必须树立科学的发展观 ,深入开展皮革工业的环境建设 ,同时必须树立正确的国情观、资源观、效益观、法制观 ,从而推动皮革工业可持续发展战略的落实  相似文献   

16.
By reducing the energy and materials required to provide goods and services, nanotechnology has the potential to provide more appealing products while improving environmental performance and sustainability. Whether and how soon this potential could be realized depends on phrasing the right research and development (R&D) questions and pursuing commercialization intelligently. A sufficiently broad perspective at the outset is required to understand economic and technical feasibility, estimate life cycle environmental implications, and minimize unanticipated negative impacts. The rapid rise in federally funded nanotechnology R&D dictates that consideration of societal benefits will have a large role in setting the R&D agenda. We estimate potential selected economic and environmental impacts associated with the use of nanotechnology in the automotive industry. In particular, we project the material processing and fuel economy benefits associated with using a clay-polypropylene nanocomposite instead of steel or aluminum in light-duty vehicle body panels. Although the manufacturing cost is currently higher, a life cycle analysis shows potential benefits in reducing energy use and environment discharges by using a nanocomposite design.  相似文献   

17.
The objective of this paper is to reveal to what degree biobased jet fuels (biojet) can reduce greenhouse gas (GHG) emissions from the U.S. aviation sector. A model of the supply and demand chain of biojet involving farmers, biorefineries, airlines, and policymakers is developed by considering factors that drive the decisions of actors (i.e., decision-makers and stakeholders) in the life cycle stages. Two kinds of feedstock are considered: oil-producing feedstock (i.e., camelina and algae) and lignocellulosic biomass (i.e., corn stover, switchgrass, and short rotation woody crops). By factoring in farmer/feedstock producer and biorefinery profitability requirements and risk attitudes, land availability and suitability, as well as a time delay and technological learning factor, a more realistic estimate of the level of biojet supply and emissions reduction can be developed under different oil price assumptions. Factors that drive biojet GHG emissions and unit production costs from each feedstock are identified and quantified. Overall, this study finds that at likely adoption rates biojet alone would not be sufficient to achieve the aviation emissions reduction target. In 2050, under high oil price scenario assumption, GHG emissions can be reduced to a level ranging from 55 to 92%, with a median value of 74%, compared to the 2005 baseline level.  相似文献   

18.
In addition to available country or site-specific life cycle studies on Jatropha biodiesel we present a generic, location-independent life cycle assessment and provide a general but in-depth analysis of the environmental performance of Jatropha biodiesel for transportation. Additionally, we assess the influence of changes in byproduct use and production chain. In our assessments, we went beyond the impact on energy requirement and global warming by including impacts on ozone layer and terrestrial acidification and eutrophication. The basic Jatropha biodiesel system consumes eight times less nonrenewable energy than conventional diesel and reduces greenhouse gas emissions by 51%. This result coincides with the lower limit of the range of reduction percentages available in literature for this system and for other liquid biofuels. The impact on the ozone layer is also lower than that provoked by fossil diesel, although eutrophication and acidification increase eight times. This study investigates the general impact trends of the Jatropha system, although not considering land-use change. The results are useful as a benchmark against which other biodiesel systems can be evaluated, to calculate repayment times for land-use change induced carbon loss or as guideline with default values for assessing the environmental performance of specific variants of the system.  相似文献   

19.
We use life cycle assessment methodology to compare three disposal options for unused pharmaceuticals: (i) incineration after take-back to a pharmacy, (ii) wastewater treatment after toilet disposal, and (iii) landfilling or incineration after trash disposal. For each option, emissions of active pharmaceutical ingredients to the environment (API emissions) are estimated along with nine other types of emissions to air and water (non-API emissions). Under a scenario with 50% take-back to a pharmacy and 50% trash disposal, current API emissions are expected to be reduced by 93%. This is within 6% of a 100% trash disposal scenario, which achieves an 88% reduction. The 50% take-back scenario achieves a modest reduction in API emissions over a 100% trash scenario while increasing most non-API emissions by over 300%. If the 50% of unused pharmaceuticals not taken-back are toileted instead of trashed, all emissions increase relative to 100% trash disposal. Evidence suggests that 50% participation in take-back programs could be an upper bound. As a result, we recommend trash disposal for unused pharmaceuticals. A 100% trash disposal program would have similar API emissions to a take-back program with 50% participation, while also having significantly lower non-API emissions, lower financial costs, higher convenience, and higher compliance rates.  相似文献   

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