Context Of Life Cycle Assessment Research Articles

Critical review of methods and models for biodiversity impact assessment and their applicability in the LCA context

Global biodiversity is in rapid decline and halting biodiversity loss is one of the most important challenges humanity must tackle now and in the immediate future. The five main direct drivers of biodiversity loss are climate change, pollution, land use, overexploitation of resources and the spread of invasive species, which result from indirect drivers such as unsustainable production and consumption. It is therefore of paramount importance that scientifically robust methods are developed to capture impacts on biodiversity from a value-chain perspective. Life Cycle Assessment (LCA) methodology allows to quantify the impact of products and organisations throughout their whole life cycle. In the LCA framework, several methods for biodiversity impact assessment have been developed. Building on previous reviews, this article aims to critically analyse methods and models for biodiversity impact assessment in LCA and beyond as comprehensively as possible, and to select those that may be most suitable for application in an LCA context. 64 methods were reviewed and 23 were selected for a detailed analysis based on availability of documentation, domain of application, geographical scope, potential to be used in LCA, and added value. The analysis addressed their goal and scope, data use and needs, and impact assessment characteristics, revealing strengths and weaknesses of the methods. There is currently no method that takes well into account at the same time the variety of pressures on biodiversity, ecosystems, taxonomic groups, essential biodiversity variables classes, and the fundamental aspects to consider in biodiversity impact assessments – but for each of these five criteria, we show which methods perform best. For the future development of biodiversity impact assessment, it is required to improve the coverage of drivers of biodiversity loss, increase ecosystem and taxonomic coverage, include the assessment of ecosystem services, and develop robust indicators that allow for complementary analysis of more essential biodiversity aspects.

The Eco-Costs of Material Scarcity, a Resource Indicator for LCA, Derived from a Statistical Analysis on Excessive Price Peaks

The availability of resources is crucial for the socio-economic stability of our society. For more than two decades, there was a debate on how to structure this issue within the context of life-Cycle assessment (LCA). The classical approach with LCA is to describe “scarcity” for future generations (100–1000 years) in terms of absolute depletion. The problem, however, is that the long-term availability is simply not known (within a factor of 100–1000). Outside the LCA community, the short-term supply risks (10–30 years) were predicted, resulting in the list of critical raw materials (CRM) of the European Union (EU), and the British risk list. The methodology used, however, cannot easily be transposed and applied into LCA calculations. This paper presents a new approach to the issue of short-term material supply shortages, based on subsequent sudden price jumps, which can lead to socio-economic instability. The basic approach is that each resource is characterized by its own specific supply chain with its specific price volatility. The eco-costs of material scarcity are derived from the so-called value at risk (VAR), a well-known statistical risk indicator in the financial world. This paper provides a list of indicators for 42 metals. An advantage of the system is that it is directly related to business risks, and is relatively easy to understand. A disadvantage is that “statistics of the past” might not be replicated in the future (e.g., when changing from structural oversupply to overdemand, or vice versa, which appeared an issue for two companion metals over the last 30 years). Further research is recommended to improve the statistics.

Modeling pharmaceutical emissions and their toxicity-related effects in life cycle assessment (LCA): A review.

Over the last few decades, worldwide detection of active pharmaceutical ingredients (APIs) in aquatic environments and the associated toxicological effects on wildlife and human health have become a matter of public and scientific debate. While life cycle assessment (LCA) and life cycle impact assessment (LCIA) models are increasingly used to assess the potential eco- and human-toxicological effects of chemical emissions, few studies have looked into the issue of modeling pharmaceutical emissions specifically and their toxicity-related effects in an LCA context. This paper reviews the state of the art to inventory and characterize API emissions in LCA with the goal to identify relevant gaps and challenges. A search for 208 environmentally relevant APIs in 2 life cycle inventory (LCI) databases revealed a meager representation of this group of chemicals. Similarly, the LCIA model USEtox was found to include characterization factors (CFs) for less than 60 APIs. First approaches to model API emissions in LCA were identified on the basis of an examination of 40 LCA case studies in the pharmaceutical sector and in the field of wastewater treatment. Moreover, CFs for 79 additional APIs, expressing their ecotoxicity and/or human toxicity potential, were gathered from literature. An analysis of the variability of API-CFs in different LCIA models showed a variation of about 2-3 orders of magnitude. Based on the review results, 3 main gaps in the modeling and characterization of API emissions in an LCA context were identified: (1) incomplete modeling of API flows and API emissions along the life cycle of human pharmaceuticals, especially during their use and end-of-life phase, (2) limited API coverage in existing LCIA toxicity models, and (3) missing pharma-specific impact pathways (e.g., endocrine disruption and antibiotic resistance) in existing LCIA models. Recommendations to tackle these gaps are provided, and priority action steps are discussed. Integr Environ Assess Manag 2019;15:6-18. © 2018 SETAC.

Cadmium biosorption by alginate extraction waste and process overview in Life Cycle Assessment context

Abstract This work evaluated the cadmium biosorption capacity by the alginate extraction residue from brown seaweed Sargassum filipendula, an industry waste which is often discharged into the sea. The biosorption kinetics and equilibrium were investigated, with further analysis of the process thermodynamics. The Mass Transfer in External Film model best described the kinetic data and the rate controlling step is the diffusion through the boundary layer. The kinetic constant values of the model were 0.129, 0.064 and 0.066 1/min for initial concentrations of 1.0, 1.5 and 2.0 mmoL/L, respectively. The isotherms were obtained at four temperatures (293, 303, 313 and 323 K) and were analyzed by Langmuir, Freundlich and Dubinin-Radushkevich models. The system was better described by Freundlich model, and the Dubinin-Radushkevich model suggested that the cadmium uptake is of physical nature. The maximum biosorption capacity obtained at 293 and 303 K were 0.394 and 0.429 mmoL/g, respectively. The thermodynamic parameters indicated that the biosorption of cadmium is spontaneous and exothermic. The simplified LCA showed that the use of dealginated residue would lead to lower environmental impacts for Acidification, Climate Change, Eutrophication, Human Toxicity and Photochemical Oxidation.

Comprehensive Assessment of Human Health Impacts and Benefits of Fruits and Vegetables in a LCA Context

Nutritional effects from the ‘use stage’ of the life cycle of food products can have a substantial effect on human health; yet, they are often not considered in life cycle assessment (LCA). In this...

Including the spatial variability of metal speciation in the effect factor in life cycle impact assessment: Limits of the equilibrium partitioning method.

In life cycle assessment (LCA), the potential terrestrial ecotoxicity effect of metals, calculated as the effect factor (EF), is usually extrapolated from aquatic ecotoxicological data using the equilibrium partitioning method (EqP) as it is more readily available than terrestrial data. However, when following the AMI recommendations (i.e. with at least enough species that represents three different phyla), there are not enough terrestrial data for which soil properties or metal speciation during ecotoxicological testing are specified to account for the influence of soil property variations on metal speciation when using this approach. Alternatively, the TBLM (Terrestrial Biotic Ligand Model) has been used to determine an EF that accounts for speciation, but is not available for metals; hence it cannot be consistently applied to metals in an LCA context. This paper proposes an approach to include metal speciation by regionalizing the EqP method for Cu, Ni and Zn with a geochemical speciation model (the Windermere Humic Aqueous Model 7.0), for 5213 soils selected from the Harmonized World Soil Database. Results obtained by this approach (EFEqPregionalized) are compared to the EFs calculated with the conventional EqP method, to the EFs based on available terrestrial data and to the EFs calculated with the TBLM (EFTBLMregionalized) when available. The spatial variability contribution of the EF to the overall spatial variability of the characterization factor (CF) has been analyzed. It was found that the EFsEqPregionalized show a significant spatial variability. The EFs calculated with the two non-regionalized methods (EqP and terrestrial data) fall within the range of the EFsEqPregionalized. The EFsTBLMregionalized cover a larger range of values than the EFsEqPregionalized but the two methods are not correlated. This paper highlights the importance of including speciation into the terrestrial EF and shows that using the regionalized EqP approach is not an acceptable proxy for terrestrial ecotoxicological data even if it can be applied to all metals.

Criteria for the evaluation of life cycle assessment software packages and life cycle inventory data with application to concrete

Life cycle assessment (LCA) software packages have proliferated and evolved as LCA has developed and grown. There are now a multitude of LCA software packages that must be critically evaluated by users. Prior to conducting a comparative LCA study on different concrete materials, it is necessary to examine a variety of software packages for this specific purpose. The paper evaluates five LCA tools in the context of the LCA of seven concrete mix designs (conventional concrete, concrete with fly ash, slag, silica fume or limestone as cement replacement, recycled aggregate concrete, and photocatalytic concrete). Three key evaluation criteria required to assess the quality of analysis are adequate flexibility, sophistication and complexity of analysis, and usefulness of outputs. The quality of life cycle inventory (LCI) data included in each software package is also assessed for its reliability, completeness, and correlation to the scope of LCA of concrete products in Canada. A questionnaire is developed for evaluating LCA software packages and is applied to five LCA tools. The result is the selection of a software package for the specific context of LCA of concrete materials in Canada, which will be used to complete a full LCA study. The software package with the highest score is software package C (SP-C), with 44 out of a possible 48 points. Its main advantage is that it allows for the user to have a high level of control over the system being modeled and the calculation methods used. This comparative study highlights the importance of selecting a software package that is appropriate for a specific research project. The ability to accurately model the chosen functional unit and system boundary is an important selection criterion. This study demonstrates a method to enable a critical and rigorous comparison without excessive and redundant duplication of efforts.

Using the planetary boundaries framework for setting impact-reduction targets in LCA contexts

The planetary boundaries (PBs) framework suggests global limits for environmental interventions which could be used to set global goals for reducing environmental impacts. This paper proposes a procedure for using such global goals for setting impact-reduction targets at the scale of products for use, for example, in life cycle assessment (LCA) contexts, e.g. as a basis for evaluating the potential of interventions to reduce the environmental impact of products. The procedure consists of four steps: (i) identifying the PBs quantified in literature that correspond to an impact category which is studied in the product assessment context in question; (ii) interpreting what the identified PBs imply in terms of global impact-reduction targets; (iii) translating the outcome of (ii) to reduction targets for the particular global market segment to which the studied product belongs; and (iv) translating the outcome of (iii) to reduction targets for the studied product. The procedure requires some assumptions and value-based choices—the influence of these is tested by applying the procedure in a specific LCA context: a study of Swedish clothing consumption. The application of the procedure in an LCA context suggested the need for eliminating all or nearly all impact of Swedish clothing consumption for most impact categories. Thus, it is improbable that a single type of impact-reduction intervention (e.g. technological development or changed user behaviour) is sufficient. The outcome’s strong dependence on impact category suggests that the procedure can help in prioritising among impact categories. Furthermore, the outcome exhibited a strong dependence on the chosen method for allocating the globally allowed impact between regions—this was tested by applying different principles identified in a literature review on the allocation of emissions rights. The outcome also strongly depended on the geographical scope—this was tested by changing the geographical scope from Sweden to Nigeria. The proposed procedure is feasible to use for LCA practitioners and other environmental analysts, and data is available to apply the procedure in contexts with different geographical scopes. Value-based choices are, however, unavoidable and significantly influence the outcome, which accentuates the subjectivity and potentially controversial nature of allocating a finite impact space to certain regions, market segments and products. How to match PBs with appropriate LCA impact categories is an important area for future research.

Exploring the Use of Ecological Footprint in Life Cycle Impact Assessment

Ecological footprint (EF) is a metric that estimates human consumption of biological resources and products, along with generation of waste greenhouse gas (GHG) emissions in terms of appropriated productive land. There is an opportunity to better characterize land occupation and effects on the carbon cycle in life cycle assessment (LCA) models using EF concepts. Both LCA and EF may benefit from the merging of approaches commonly used separately by practitioners of these two methods. However, few studies have compared or integrated EF with LCA. The focus of this research was to explore methods for improving the characterization of land occupation within LCA by considering the EF method, either as a complementary tool or impact assessment method. Biofuels provide an interesting subject for application of EF in the LCA context because two of the most important issues surrounding biofuels are land occupation (changes, availability, and so on) and GHG balances, two of the impacts that EF is able to capture. We apply EF to existing fuel LCA land occupation and emissions data and project EF for future scenarios for U.S. transportation fuels. We find that LCA studies can benefit from lessons learned in EF about appropriately modeling productive land occupation and facilitating clear communication of meaningful results, but find limitations to the EF in the LCA context that demand refinement and recommend that EF always be used along with other indicators and metrics in product-level assessments

Abiotic resources: new impact assessment approaches in view of resource efficiency and resource criticality—55th Discussion Forum on Life Cycle Assessment, Zurich, Switzerland, April 11, 2014

Natural abiotic resources (here referring primarily to metals, minerals and fossil resources) have become a growing political concern with increased focus on resource scarcity, natural availability and dependency on foreign supply. For a nearterm time horizon, both the USA and the EU have identified so-called critical raw materials including platinum group metals, rare earth elements, etc. (EC 2010; NRC 2008), and resource efficiency has become one key element of the sustainability policy of the EU and Switzerland (EC 2011a; Bundesrat 2012). Within the context of life cycle assessment (LCA), the development of life cycle impact assessment (LCIA) methods has been very diverse without a unifying practice for how to assess the depletion of abiotic resources from the natural environment (Carvalho et al. 2014; EC 2011b; Klinglmair et al. 2013; Mancini et al. 2013). The overarching goal of the 55th Discussion Forum on LCA (DF-55) was to present and discuss recent developments of novel and updated LCIA approaches with respect to the relevance of resources as a separate safeguard subject (or area of protection, AoP) in environmental assessment, the rationale and interpretations of their respective environmental mechanisms related to abiotic resource depletion and the relation to other resource-related concerns such as scarcity and criticality. Setting the stage for the discussion forum, the first presentation of the day was given by Stefanie Hellweg (ETH Zurich, Switzerland) who gave an overview of the various issues related to the assessment of abiotic resource depletion. The extraction rates and the number of resources put into use are increasing and products are becoming more complex. The resulting heterogeneity of materials and products poses great challenges for recycling and recovery of the resources. In this context, three different methodologies for addressing different issues or questions related to the management of resources were outlined:

Time Horizon and Dominance in Dynamic Life Cycle Assessment

SummaryTemporal aspects have traditionally not been recognized adequately in life cycle assessment (LCA). The dynamic LCA model recently proposed offers a significant step forward in the dynamic assessment of global warming impacts. The results obtained with dynamic LCA are highly sensitive to the choice of a time horizon. Therefore, decision making between alternative systems can be critical because conclusions are dependent on the specific time horizon. In this article, we develop a decision‐making methodology based on the concept of time dominance. We introduce instantaneous and cumulative time dominance criteria to the dynamic LCA context and argue why the dominance of an alternative should also imply preference. Our approach allows for the rejection of certain alternatives without the determination of a specific time horizon. The number of decision‐relevant alternatives can thereby be reduced and the decision problem facilitated. We demonstrate our methodology by means of a case study of end‐of‐life alternatives for a wooden chair derived from the original authors of dynamic LCA and discuss the implications and limitations of the approach. The methodology based on time dominance criteria is supplementary to the dynamic LCA model, but does not substitute it. The overall value of this article stretches beyond LCA onto more general assessments of global warming, for example, in policy where the choice of a time horizon is equally significant.

Including the Introduction of Exotic Species in Life Cycle Impact Assessment: The Case of Inland Shipping

While the ecological impact of anthropogenically introduced exotic species is considered a major threat for biodiversity and ecosystems functioning, it is generally not accounted for in the environmental life cycle assessment (LCA) of products. In this article, we propose a framework that includes exotic species introduction in an LCA context. We derived characterization factors for exotic fish species introduction related to the transport of goods across the Rhine-Main-Danube canal. These characterization factors are expressed as the potentially disappeared fraction (PDF) of native freshwater fish species in the rivers Rhine and Danube integrated over space and time per amount of goods transported (PDF·m(3)·yr·kg(-1)). Furthermore, we quantified the relative importance of exotic fish species introduction compared to other anthropogenic stressors in the freshwater environment (i.e., eutrophication, ecotoxicity, greenhouse gases, and water consumption) for transport of goods through the Rhine-Main-Danube waterway. We found that the introduction of exotic fish species contributed to 70-85% of the total freshwater ecosystem impact, depending on the distance that goods were transported. Our analysis showed that it is relevant and feasible to include the introduction of exotic species in an LCA framework. The proposed framework can be further extended by including the impacts of other exotic species groups, types of water bodies and pathways for introduction.

Building Materials in the Operational Phase

SummaryHow sustainable are the various building materials, and what are the criteria for assessment? The scope of this article is to explore in what ways responsible and conscious use of materials can yield environmental benefits in buildings. In particular, it discusses how material properties related to thermal and hygroscopic mass can be utilized for achieving energy efficiency and good indoor air quality, and how these gains can be included into the context of life cycle assessment (LCA).A case study investigates and compares carbon impacts related to three design concepts for an exterior wall: (A) concrete/rock wool; (B) wood studs/wood fiber; and (C) wood studs/hemp lime. The thermal performance of concepts B and C are modeled to comply with concept A regarding both thermal transmittance (U‐value) and dynamic heat flow (Q24h) using the design tool WUFI Pro. An environmental cost‐benefit analysis is then accomplished in four steps, regarding (1) manufacturing and transport loads, (2) carbon sequestration in plant‐based materials and recarbonation in concrete/lime, and (3 and 4) potentially reduced operational energy consumption caused by heat and moisture buffering. The input data are based on suggested values and effects found in the literature.The summarized results show that wall A has the highest embodied carbon and the lowest carbon storage and recarbonation effects, whereas wall C2 has the lowest embodied carbon and the highest carbon storage and recarbonation effects. Regarding buffering effects, wall A has the highest potential for thermal buffering, whereas wall C has the highest potential for moisture buffering.

Regional Characterization of Freshwater Use in LCA: Modeling Direct Impacts on Human Health

Life cycle assessment (LCA) is a methodology that quantifies potential environmental impacts for comparative purposes in a decision-making context. While potential environmental impacts from pollutant emissions into water are characterized in LCA, impacts from water unavailability are not yet fully quantified. Water use can make the resource unavailable to other users by displacement or quality degradation. A reduction in water availability to human users can potentially affect human health. If financial resources are available, there can be adaptations that may, in turn, shift the environmental burdens to other life cycle stages and impact categories. This paper proposes a model to evaluate these potential impacts in an LCA context. It considers the water that is withdrawn and released, its quality and scarcity in order to evaluate the loss of functionality associated with water uses. Regionalized results are presented for impacts on human health for two modeling approaches regarding affected users, including or not domestic uses, and expressed in disability-adjusted life years (DALY). A consumption and quality based scarcity indicator is also proposed as a midpoint. An illustrative example is presented for the production of corrugated board with different effluents, demonstrating the importance of considering quality, process effluents and the difference between the modeling approaches.

Emergy as a Life Cycle Impact Assessment Indicator

Summary Founded in thermodynamics and systems ecology, emergy evaluation is a method to associate a product with its dependencies on all upstream environmental and resource flows using a common unit of energy. Emergy is thus proposed as an indicator of aggregate resource use for life cycle assessment (LCA). An LCA of gold mining, based on an original life cycle inventory of a large gold mine in Peru, is used to demonstrate how emergy can be incorporated as an impact indicator into a process-based LCA model. The results demonstrate the usefulness of emergy in the LCA context. The adaptation of emergy evaluation, traditionally performed outside of the LCA framework, requires changes to the conventional accounting rules and the incorporation of uncertainty estimations of the emergy conversion factors, or unit emergy values. At the same time, traditional LCA boundaries are extended to incorporate the environmental processes that provide for raw resources, including ores. The total environmental contribution to the product, dor´ e, is dominated by mining and metallurgical processes and not the geological processes forming the gold ore. The measure of environmental contribution to 1 gram (g) of dor´ ei s 6.8E+ 12 solar-equivalent Joules (sej) and can be considered accurate within a factor of 2. These results are useful in assessing a process in light of available resources, which is essential to measuring long-term sustainability. Comparisons are made between emergy and other measures of resource use, and recommendations are made for future incorporation of emergy into LCA that will result in greater consistency with existing life cycle inventory (LCI) databases and other LCA indicators.

Environmental Assessment of Micro/Nano Production in a Life Cycle Perspective

AbstractThe concept of life cycle assessment (LCA) is build upon the object of assessment, namely the functional unit, i.e. all impacts etc. are related to a specific service or function in the society. In a LCA context, the assessment of emerging technologies like Nanotechnology is challenging due to a number of knowledge gaps. It may not be known exactly what is the function (or functional unit) or what the technology may substitute and production may still be at an experimental level, raising questions about technology or materials choice.For prospective LCA studies methodologies like “consequential LCA” may be useful because future changes are taken into account. However, it still does not suffice for emerging technologies. In a recent “Green Technology Foresight” project a methodology was developed based on five elements: Life-cycle thinking, systems approach, a broad dialogue based understanding of the environment, precaution as a principle and finally, prevention as preferred strategy. When assessing emerging technologies three levels should be considered. First order effects are connected directly to production, use and disposal. Second order are effects from interaction with other parts of the economy from more intelligent design and management of processes, products, services, product chains etc. and the effect on the stocks of products. An example could be dematerialisation. Rebound effects may be considered as third order effects, like when efficiency gains stimulate new demands, which balances or overcompensates the savings.In the Micro/Nano Production area a range of new possibilities arise both within applications, production technology and materials. The Department of Manufacturing Engineering and Management at The Technical University of Denmark has staked on a joint effort in manufacturing engineering and environmental assessment for eco efficiency improvement. A review of knowledge and studies on environmental assessments in the micro/nano technology area is performed and will be used to further detail the general framework for assessment outlined above to be more specific for micro/nano production.

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