Application of Life Cycle Assessment for the Environmental Certificate of the Mercedes-Benz S-Class (7 pp)

Background, Aims and Scope Life cycle assessment (LCA) is used as a tool for design for environment (DfE) to improve the environmental performance of the Mercedes Car Group products. For the new S-Class model a brochure including an environmental certificate and comprehensive data for the product was published for the first time. The paper explains the use of LCA for these applications and presents exemplary results. Methods The environmental certificate brochure reports on processes, data and results based on the international standards for life cycle assessment (ISO 14040, ISO 14041, ISO 14042, ISO 14043), for environmental labels and declarations (ISO 14020, ISO 14021) and for the integration of environmental aspects into product design and development (ISO 14062), which are accepted by all stakeholders. Results and Discussion The compliance with these international standards and the correctness of the information contained in the certificate were reviewed and certified by independent experts. The global warming potential (GWP 100 years) of the new S-Class vehicle was reduced by 6%, the acidification potential by 2%, the eutrophication potential by 13% and the photochemical ozone creation potential by 9%. In addition, the use of parts made from renewable materials was increased by 73 percent to a total of 27 parts with a weight of about 43 kilograms. A total of 45 parts with a weight of 21.2 kilograms can be manufactured using a percentage of recycled plastics. Conclusion The application of LCA for DfE is fully integrated as a standard function in the vehicle development process. The DfE/LCA approach at the Mercedes Car Group was successful in improving the environmental performance of the new S-Class. It is shown that the objective of improving the environmental performance of the new S-Class model, compared to the previous one, was achieved. Recommendation and Outlook Vehicles are complex products with very complex interactions with the environment. Therefore, simple solutions, e.g. pure focus on fuel economy or light weighting or recycling or single material strategies, are bound to fail. It is a main task of DfE and LCA to take this fact into account and come up with more intelligent solutions. The application of LCAs for DfE and their integration as standard practice in the product development process is both the most demanding and the most rewarding. It requires a substantial effort to acquire the know-how, the data, the experience and the tools needed to generate meaningful results just in time. However, this is the way how LCA and DfE can add value – they have to be 'built' into the product.     

Plastics recycling: challenges and opportunities

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide.Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel.While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it may be possible to divert the majority of plastic waste from landfills to recycling over the next decades.     

Life cycle assessment of commercial furniture: a case study of Formway LIFE chair

Background, aims and scope  The environmental aspects of companies and their products are becoming more significant in delivering competitive advantage. Formway Furniture, a designer and manufacturer of office furniture products, is a New Zealand-based company that is committed to sustainable development. It manufactures two models of the light, intuitive, flexible and environmental (LIFE) office chair: one with an aluminium base and one with a glass-filled nylon (GFN) base. It was decided to undertake a life cycle assessment (LCA) study of these two models in order to: (1) determine environmental hotspots in the life cycle of the two chairs (goal 1); (2) compare the life cycle impacts of the two chairs (goal 2); and (3) compare alternative potential waste-management scenarios (goal 3). The study also included sensitivity analysis with respect to recycled content of aluminium in the product. Materials and methods  The LIFE chair models consist of a mix of metal and plastic components manufactured by selected Formway suppliers according to design criteria. Hence, the research methodology included determining the specific material composition of the two chair models and acquisition of manufacturing data from individual suppliers. These data were compiled and used in conjunction with pre-existing data, specifically from the ecoinvent database purchased in conjunction with the SimaPro7 LCA software, to develop the life cycle inventory of the two chair models. The life cycle stages included in the study extended from raw-material extraction through to waste management. Impact assessment was carried out using CML 2 baseline 2000, the methodology developed by Leiden University’s Institute for Environmental Sciences. Results  This paper presents results for global warming potential (GWP100). The study showed a significant impact contribution from the raw-material extraction/refinement stage for both chair models; aluminium extraction and refining made the greatest contribution to GWP100. The comparison of the two LIFE chair models showed that the model with the aluminium base had a higher GWP100 impact than the model with the GFN base. The waste-management scenario compared the GWP100 result when (1) both chair models were sent to landfill and (2) steel and aluminium components were recycled with the remainder of the chair sent to landfill. The results showed that the recycling scenario contributed to a reduced GWP100 result. Since production and processing of aluminium was found to be significant, a sensitivity analysis was carried out to determine the impact of using aluminium with different recycled contents (0%, 34% and 100%) in both waste-management scenarios; this showed that increased use of recycled aluminium was beneficial. The recycling at end-of-life scenarios was modelled using two different end-of-life allocation approaches, i.e. consequential and attributional, in order to illustrate the variation in results caused by choice of allocation approach. The results using the consequential approach showed that recycling at end-of-life was beneficial, while use of the attributional method led to a similar GWP100 as that seen for the landfill scenario. Discussion  The results show that the main hotspot in the life cycle is the raw-material extraction/refinement stage. This can be attributed to the extraction and processing of aluminium, a material that is energy intensive. The LIFE chair model with the aluminium base has a higher GWP100 as it contains more aluminium. Sensitivity analysis pertaining to the recycled content of aluminium showed that use of aluminium with high recycled content was beneficial; this is because production of recycled aluminium is less energy intensive than production of primary aluminium. The waste-management scenario showed that recycling at end-of-life resulted in a significantly lower GWP100 than landfilling at end-of-life. However, this result is dependent upon the modelling approach used for recycling. Conclusions  With respect to goal 1, the study found that the raw-material extraction/refinement stage of the life cycle was a significant factor for both LIFE chair models. This was largely due to the use of aluminium in the product. For goal 2, it was found that the LIFE chair model with the aluminium base had a higher GWP100 than the GFN model, again due to the material content of the two models. Results for goal 3 illustrated that recycling at end-of-life is beneficial when using a system expansion (consequential) approach to model recycling; if an attributional ‘cut-off’ approach is used to model recycling at end-of-life, there is virtually no difference in the results between landfilling and recycling. Sensitivity analysis pertaining to the recycled content of aluminium showed that use of higher recycled contents leads to a lower GWP100 impact. Recommendation and perspectives  Most of the GWP100 impact was contributed during the raw-material extraction/refinement stage of the life cycle; thus, the overall impact of both LIFE chair models may be reduced through engaging in material choice and supply chain environmental management with respect to environmental requirements. The study identified aluminium components as a major contributor to GWP100 for both LIFE chair models and also highlighted the sensitivity of the results to its recycled content. Thus, it is recommended that the use of aluminium in future product designs be limited unless it is possible to use aluminium with a high recycled content. With respect to waste management, it was found that a substantial reduction in the GWP100 impact would occur if the chairs are recycled rather than landfilled, assuming an expanding market for aluminium. Thus, recycling the two LIFE chair models at end-of-life is highly recommended.     

Life Cycle costing as part of design for environment environmental business cases

Background  In developing products various requirements have to be integrated including functionality, quality, affordability as well as environmental aspects. Often conflicting requirements have to be fulfilled. Therefore, multi-dimensional decision support approaches are necessary. Methods  Here, one approach is to relate the conflicting requirements to each other. Life Cycle Costing (LCC) has the potential to support the trade-off between some environmental targets and overall affordability targets by including all monetary flows along the product life cycle (going beyond the well-known costs of ownership by integrating also long-term use and end-of-life costs). Those solutions can be identified that (a) have the highest efficiencies (where do we get most environmental improvements per Ϊ and (b) have the highest affordability for the customer along the life cycle. Furthermore, on-costs in the design phase can be justified in terms of future savings either for the customer or for the recycling of the products. These represent real business cases for environmental actions. Three types of environmental business cases can be differentiated. Results and Discussion  This paper presents various examples where LCC is integrated into product design. However, there are a number of open issues in the implementation of LCC within real product development including data availability and uncertainty (future costs/ savings), level of discounting, accounting and compensation. Various internal case studies done in the last years showed that already few changes in the costs structure can significantly affect the identi-fied future costs. Recommendation and Outlook  Uncertainties in LCC are higher than in LCA and highest when applied in the stage of product develop-ment, i.e. used to support DfE action. As a consequence, the result-ing figures can only be seen as directional. Therefore, the use of LCC in Design for Environment cannot be recommended without major restrictions in terms of guidance, experience/training. The link-age between LCC and DfE can either be established via (1) experts supporting design teams or (2) as part of a DfE tool. The DfE tool has to include detailed guidance for interpretation, and its application should be based on a solid training for DfE engineers.     

Biological degradation of plastics: a comprehensive review

Lack of degradability and the closing of landfill sites as well as growing water and land pollution problems have led to concern about plastics. With the excessive use of plastics and increasing pressure being placed on capacities available for plastic waste disposal, the need for biodegradable plastics and biodegradation of plastic wastes has assumed increasing importance in the last few years. Awareness of the waste problem and its impact on the environment has awakened new interest in the area of degradable polymers. The interest in environmental issues is growing and there are increasing demands to develop material which do not burden the environment significantly. Biodegradation is necessary for water-soluble or water-immiscible polymers because they eventually enter streams which can neither be recycled nor incinerated. It is important to consider the microbial degradation of natural and synthetic polymers in order to understand what is necessary for biodegradation and the mechanisms involved. This requires understanding of the interactions between materials and microorganisms and the biochemical changes involved. Widespread studies on the biodegradation of plastics have been carried out in order to overcome the environmental problems associated with synthetic plastic waste. This paper reviews the current research on the biodegradation of biodegradable and also the conventional synthetic plastics and also use of various techniques for the analysis of degradation in vitro.     

Recent Advances in Design for Environment at Motorola

Motorola is a large electronics company that uses design for environment (DfE) t o address our customers' environmental needs. In working to integrate environmental considerations into product design, Motorola has encountered new challenges in product design, and as a result has had to develop new frameworks and employ new analytical tools. This article describes those challenges and Motorola's efforts to date. The examination of how products are designed in Motorola led to the realization that there are distinct phases in design: concept development, detail design, and prototype manufacture. In the earlier phases where the greatest flexibility for product reconfiguration exists, there is the least amount of detailed information available for use in making environmental assessments. In an effort to match the data availability to the environmental assessment needs, Motorola developed a tiered approach to DE using a matrix-based abridged life-cycle assessment (LCA) in the concept development stage, a scoring system based in part on multiattribute value theory in the detail design stage, and potentially full-scale life-cycle assessment in the prototype manufacturing stage.     

生物可降解塑料在不同环境条件下的降解研究进展北大核心CSCD

当前社会塑料制品的使用需求持续增加,塑料垃圾处理压力不断增大,减缓塑料污染成为当务之急,生物可降解塑料因可在一定生物活性环境下较快降解而备受关注,具有广阔的应用前景。生物可降解塑料降解条件复杂,影响因素众多,对不同生物可降解塑料降解规律,降解微生物和功能酶的透彻掌握,是实现其全面利用和高效资源化处理处置的基础和前提。文章系统梳理了常见生物可降解塑料的种类、性能、优缺点和主要用途,全面综述了生物可降解塑料的降解机理、降解微生物和功能酶,以及生物可降解塑料在不同环境条件下的降解周期和程度,以期为生物可降解塑料的微生物降解研究提供借鉴,为生物可降解塑料废弃物的高效处理处置和彻底降解提供科学参考。     

Eco-efficiency of Advanced Loop-closing Systems for Vehicles and Household Appliances in Hyogo Eco-town

The closing of material loops is a critical challenge in industrial ecology. It relies mainly on the utilization of recovered materials/parts/products in the original and principal production system while their original function is retained at the highest level possible. In this study, advanced loop-closing systems for the recycling of end-of-life vehicles and electric household appliances are first designed in "Hyogo Eco-town." Second, a methodology for evaluating the eco-efficiency of these systems is developed. Finally, the eco-efficiency of the designed advanced loop-closing strategies for the two products is evaluated, based on the results of materials flow analysis and life-cycle assessment.
The results show that, compared with conventional recycling systems, when an industrial complex and an advanced loop-closing system for end-of-life vehicles are established, the total economic value increases by 114% and the eco-efficiency in terms of the amount of direct material input is improved by 57%. This system permits the utilization of the by-products, wastes, and recovered materials that originate from other industrial sectors as input to production activities. In the case of end-of-life electric household appliances, an advanced loop-closing strategy to lengthen the product life with parts reuse improves the eco-efficiency in terms of carbon dioxide (CO₂) emissions by 4% compared with the conventional replacement of the appliance with a new product along with the material recycling option.     

Recycling plastics from e-waste: Implications for effective eco-design

This paper presents five case studies on waste electrical and electronic equipment (WEEE) recycling to provide a coherent overview on the likely impact of eco-design measures on recycling of plastics used in energy-related products within the EU. Whilst some eco-design measures, such as improving disassembly of plastic parts, may generally benefit recycling operations, other measures were found to be ineffective or requiring further investigation. For example, product polymer marking, and provision of product-specific information was rarely utilized by participant organizations, if at all. Additionally, this study highlights a disconnect between the aims of substance bans as an eco-design measure and the impact upon plastics recycling in practice. Future research could help with quantitative and/or statistical analysis of WEEE processing to investigate across a wider selection of recyclers and recycling processes. Despite 20 years of research on eco-design, it appears that EU eco-design policies and voluntary initiatives are still being devised without adequate understanding of their impact on different types of recycling practices. Empirical research on recycling processes can provide important insight to ensure eco-design measures are effective and avoid unintended consequences for the environment.     

Proposal of a method for allocation in building-related environmental LCA based on economic parameters

Application and development of the LCA methodology to the context of the building sector makes several building specific considerations necessary, as some key characteristics of products in the building sector differ considerably from those of other industrial sectors. The largest difference is that the service life of a building can stretch over centuries, rather than decades or years as seen for consumer products. The result of the long service life is that it is difficult to obtain accurate data and to make relevant assumptions about future conditions regarding, for example, recycling. These problems have implications on the issue of allocation in the building sector, in the way that several allocation procedures ascribe environmental loads to users of recycled or reused products and materials in the future which are unknown today. The long service life for buildings, building materials and building components, is associated with the introduced concept of a virtual parallel time perspective proposed here, which basically substitutes historical and future processes and values with current data. Further, the production and refining of raw material as a parallel to upgrading of recycled material, normally contains several intermediate products. A suggestion is given for how to determine the comparability of intermediate materials. The suggested method for allocation presented is based on three basic assumptions: (1) If environmental loads are to be allocated to a succeeding product life cycle, the studied actual life cycle has to take responsibility for upgrading of the residual material into secondary resources. (2) Material characteristics and design of products are important factors to estimate the recyclable amount of the material. Therefore, a design factor is suggested using information for inherent material properties combined with information of the product context at the building level. (3) The quality reduction between the materials in two following product life cycles is indicated as the ratio between the market value for the material in the products. The presented method can be a good alternative for handling the problem of open-loop recycling allocation in the context of the building sector if a consensus for the use of the fictive parallel time perspective and the use of the design factor can be established. This as the use of the time perspective and design factor is crucial to be able to deal with the problem of long service lives for buildings and building materials and the specific characteristics of the same building materials and components built into different building contexts.     

A semi-quantitative method for the impact assessment of emissions within a simplified life cycle assessment

Intention, Goal and Scope: Dealing with data gaps, data asymmetries, and inconsistencies in life cycle inventories (LCI) is a general prohlem in Life Cycle Assessment (LCA) studies. An approach to deal with these difficulties is the simplification of LCA. A methodology that lowers the requirements for data quality (accuracy) for process emissions within a simplified LCA is introduced in this article. Background: Simplification is essential for applying LCA in the context of design for environment (DfE). The tool euroMat is a comprehensive DfE software tool that is based on a specific, simplified LCA approach, the Iterative Screening LCA (IS-LCA). Within the scope of the IS-LCA, there is a quantitative assessment of energy-related processes, as well as a semi-quantitative assessment of non-energy related emissions which supplement each other. Objectives: The semi-quantitative assessment, which is in the focus of this article, aims at lowering the requirements for the quality of non-energy related emissions data through combined use of qualitative and quantitative inventory data. Methods: Potential environmental impacts are assessed based on ABC-categories for qualities (harmfulness) of emissions and XYZ-categories for quantities of emitted substances. Employing statistical methods assignment rules for the ABC/XYZ-categories were derived from literature data and databases on emissions to air, water, and soil. Statistical tests as well as a DfE case study (comparing the materials aluminum and carbon fiber reinforced epoxy for a lightweight container to be used in an aerospace application) were conducted in order to evaluate the level of confidence and practicality of the proposed, simplified impact assessment. Results: Statistical and technical consistency checks show that the method bears a high level of confidence. Results obtained by the simplified assessment correlate to those of a detailed quantitative LCA. Conclusions: Therefore, the application of the ABC/XYZ-categories (together with the cumulative energy demand) can be considered a practical and consistent approach for determining the environmental significance of products when only incomplete emission data is available. Future Prospects: The statistical base of the method is expanded continuously since it is an integral part of the DfE software tool euroMat, which is currently being further developed. That should foster the application of the method. Outside DfE, the method should also be capable of facilitating simplified LCAs in general.     

A comparative Life Cycle assessment of building insulation products made of stone wool,paper wool and flax

Insulation of buildings in order to save heating energy is an important technology for enabling sustainable development. This paper summarises the results of a comparative LCA study according to ISO 14040 standard series of HT stone wool, flax representing crop grown products and paper wool representing recycled products applied for roof insulation. As the three materials have vastly different lifecycles, yet fulfil the same function cycles, the methodology used should be of general interest. Part 1 consists of the project background, goal and scope definition, a detailed life cycle inventory analysis with sensitivity analysis, impact assessment and interpretation. The actual comparison of the results from the life cycle assessments of the three products, in which an attempt is made to answer the question of whether the biological products flax and paper wool are more environmentally preferable than the mineral product stone wool representing more traditional insulation materials, is discussed in Part 2.     

The Role of Voluntary Industry Standards in Environmental Supply-Chain Management

Our article uses a new institutional economics (NIE) framework to explore the role of voluntary industry standards in the development and implementation of environmental supplier-management programs in the computer industry. We examine two different voluntary standards, one for the management of design for environment (DfE) in the semiconductor fabrication equipment sector and the other for assessing the implementation and use of environmental management systems throughout the computer industry supply chain. We compare and contrast the two standards to explain why the former was widely adopted and has helped integrate DfE into buyer-supplier relations among adopters, whereas the latter failed to gain acceptance. In line with NIE logic, both standards aimed to lower transaction and customization costs by setting "rules of the game" for interfirm transactions that would help simplify and routinize novel environmental supply-chain programs and activities. Their differential success can be elucidated in terms of how well each met the NIE criteria for remediableness and legitimacy. We conclude that voluntary standards have the potential to play an important role in promoting DfE in industrial supply chains. We further conclude that NIE provides a conceptual framework of great value to industrial ecologists who analyze how industry standards and other institutions help firms move toward more sustainable supply-chain management practices.     

Design of recycling system for poly(methyl methacrylate) (PMMA). Part 1: recycling scenario analysis

Introduction

In this series of papers, we present a poly(methyl methacrylate) (PMMA) recycling system design based on environmental impacts, chemical hazards, and resource availability. We evaluated the recycling system by life cycle assessment, environment, health, and safety method, and material flow analysis.

Purpose

Previous recycling systems have not focused on highly functional plastics such as PMMA, partly because of lower available volumes of waste PMMA compared with other commodity plastics such as polyethylene or polypropylene. However, with the popularization of PMMA-containing products such as liquid crystal displays, the use of PMMA is increasing and this will result in an increase in waste PMMA in the future. The design and testing of recycling systems and technologies for treating waste PMMA is therefore a high research priority. In this study, we analyze recycling of PMMA monomers under a range of scenarios.

Methods

Based on the differences between PMMA grades and their life cycles, we developed a life cycle model and designed a range of scenarios for PMMA recycling. We obtained monomer recycling process inventory data based on the operational results of a pilot plant. Using this process inventory data, we quantified life cycle greenhouse gas (LC-GHG) emissions and fossil resource consumption, and we calculated the LIME single index.

Results and discussion

PMMA produces more than twice the amount of GHG emissions than other commodity resins. Through scenario and sensitivity analyses, we demonstrated that monomer recycling is more effective than mechanical recycling. Operational modifications in the monomer recycling process can potentially decrease LC-GHG emissions.

Conclusions

Highly functional plastics should be recycled while maintaining their key functions, such as the high transparency of PMMA. Monomer recycling has the potential to achieve a closed-loop recycling of PMMA.     

The bioprocess–technological potential of the sea

Marine bioprocess engineers face a unique challenge for the millennium: designing methods for the sustainable development of known marine resources, as well as inventing a new generation of tools and processes that will enable a greater understanding of the ocean and its resources and lead to the discovery of new bioproducts for the future. The identification and application of novel, marine-derived pharmaceuticals, cosmetics, nutritional supplements, enzymes, and pigments have already been realized. The current and potential market value of these marine bioproducts is substantial. Continued discovery and development of marine resources will depend on a number of factors: identification of new bioproducts, sustainable use of the product, optimization of production, and efficient product recovery. Successfully addressing these challenges will require the integration and collaboration of mutidisciplinary teams of oceanographers, biologists, chemists, and engineers.     

Engineering new metabolic capabilities in bacteria: lessons from recombinant cellulolytic strategies

Cellulose waste biomass is the most attractive substrate for 'biorefinery strategies' producing high-value products (e.g. fuels or plastics) by fermentation. However, traditional biomass bioconversions are economically inefficient multistep processes. Thus far, no microorganisms able to perform single-step fermentation into products (consolidated bioprocessing; CBP) have been isolated. Metabolic engineering is currently employed to develop recombinant microorganisms suitable for CBP. The heterologous expression of extracellular proteins (e.g. cellulases or hemicellulases) is the key feature of recombinant cellulolytic strategies, conferring cellulolytic ability to microorganisms exhibiting high product yields and titers. Although more molecular tools are becoming available, efficient heterologous expression of secreted proteins is still a challenge. The present review summarizes both bottlenecks and solutions of organism engineering for biomass biorefinery strategies.     

Adaptation of environmental data to national and sectorial context: application for reinforcing steel sold on the French market

Purpose

Environmental data for steel products are generally proposed at a continental or a global scale. The question we are tackling here is: does the fact that steel as a global market necessarily reduces the need for national data?

Methods

In this study, the environmental impact of reinforcing steel sold in France is evaluated. To do so, a specific environmental inventory is adapted from Ecoinvent database. CML method is used for impact calculation and both methods “recycled content” as well as “end of life recycling approach” are tested.

Results and discussion

This study shows that there is a specificity of reinforcing steel products sold in France compared to European value. It is due to the fact that reinforcing steel is mainly made with recycled steel as the market growth for construction product in France is limited allowing a very high recycled content. This result is not sensitive neither to the allocation method used for recycling (cut-off approach or system expansion) nor to transport distance and electricity country mix used.

Conclusions

The result of this study can be used with confidence in every construction site work located on the French territory. Furthermore, the present study advocates for an adaptation of global database to local context defined by a specific industrial sector and a geographic region even for product such as steel that may be considered as a first approximation as a global product.     

Immunogenicity of therapeutic proteins. Part 2: impact of container closures

Immunogenicity as a potential consequence of therapeutic protein administration is increasingly being scrutinized in the biopharmaceuticals industry, particularly with the imminent introduction of biosimilar products. Immunogenicity is an important safety aspect requiring rigorous investigation to fully appreciate its impact. Factors involved in product handling, such as storage temperature, light exposure, and shaking, have been implicated in immunogenicity, while container closure systems are no less important. Intended to provide a stable environment for the dosage form, container closures may also interact with a product, affecting performance and potentially enhancing immunogenicity. Glass surfaces, air-liquid interfaces, and lubricants can mediate protein denaturation, while phthalates in plastics and latex rubber are sources of extractables and leachates that may contaminate a product, causing allergic reactions and increasing immunogenicity. The manufacture of therapeutic proteins therefore requires rigorous safety evaluations not just in the context of the product, but also product containment.     

Application of LCA as a decision-making tool for waste management systems

Aim, Scope and Background  When materials are recycled they are made available for use for several future life cycles and can therefore replace virgin material more than just once. In order to analyse the optimal waste management system for a given material, the authors have analysed the material flows in a life cycle perspective. It is important to distinguish this approach for material flow analysis for a given material from life cycle analysis of products. A product life cycle analysis analyses the product system from cradle to grave, but uses some form of allocation in order to separate the life cycle of one product from another in cases where component materials are recycled. This paper does not address allocation of burdens between different product systems, but rather focuses on methodology for decision making for waste management systems where the optimal waste management system for a given material is analysed. The focus here is the flow of the given material from cradle (raw material extraction) to grave (the material, or its inherent energy, is no longer available for use). The limitation on the number of times materials can be recycled is set by either the recycling rate, or the technical properties of the recycled material. Main Features  This article describes a mathematical geometric progression approach that can be used to expand the system boundaries and allow for recycling a given number of times. Case studies for polyethylene and paperboard are used to illustrate the importance of including these aspects when part of the Goal and Scope for the LCA study is to identify which waste management treatment options are best for a given material. The results and discussion examine the different conclusions that can be reached about which waste management option is most environmentally beneficial when the higher burdens and benefits of recycling several times are taken into account. Results  In order to assess the complete picture of the burdens and benefits arising from recycling the system boundaries must be expanded to allow for recycling many times. A mathematical geometric progression approach manages to take into account the higher burdens and benefits arising from recycling several times. If one compares different waste management systems, e.g. energy recovery with recycling, without expanding the system to include the complete effects of material recycling one can reach a different conclusion about which waste management option is preferred. Conclusions  When the purpose of the study is to compare different waste management options, it is important that the system boundaries are expanded in order to include several recycling loops where this is a physical reality. The equations given in this article can be used to include these recycling loops. The error introduced by not expanding the system boundaries can be significant. This error can be large enough to change the conclusions of a comparative study, such that material recycling followed by incineration is a much better option than waste incineration directly. Recommendations and Outlook  When comparing waste management solutions, where material recycling is a feasible option, it is important to include the relevant number of recycling loops to ensure that the benefits of material recycling are not underestimated. The methodology presented in this article should be used in future comparative studies for strategic decision-making for waste management. The approach should not be used for LCAs for product systems without due care, as this could lead to double counting of the benefits of recycling (depending on the goal and scope of the analysis). For materials where the material cycle is more of a closed loop and one cannot truly say that recycled materials replace virgin materials, a more sophisticated approach will be required, taking into account the fact that recycled materials will only replace a certain proportion of virgin materials.