Life Cycle Impact Assessment Indicators Research Articles

Life cycle sustainability assessment method for concrete

AbstractThis study aimed to develop a life cycle sustainability assessment method for concrete. An environmental impact assessment method was developed using the ELCA technique announced through the ISO 14,040 Series and KOLID, one of the life cycle impact assessment indicators. A life cycle cost assessment method was developed based on the unit price of materials and energy consumption according to the Korea Price Information. A Social Impact Assessment Method was developed by identifying appropriate major social topics and analyzing those suggested by the international organizations (UNEP). In accordance with the ‘Towards a Life Cycle Sustainability Assessment’ proposed by UNEP/SETAC, a Sustainable Concrete Index (SCI) was developed that integrates environmental, economic, and social aspects. In addition, the environmental impact of Korea’s 544 concrete types was classified by compressive strength, and the mode value was proposed as a standard concrete (environmental impact 6,662–10,785 KRW(5.02–8.12 USD), production cost 66,549–79,030 KRW(50.13–59.53 USD) so that it could be compared with the assessment concrete. As a result of selecting one ready-mix concrete business place in Korea and conducting a case study by comparing it with standard concrete, EI, CI, SI, and SCI, were analyzed to be 1.135, 1.134, 0.830, and 1.033, respectively, making it possible to quantitatively evaluate concrete sustainability.

Are Existing LCIA Methods Related to Mineral and Metal Resources Relevant for an AESA Approach Applied to the Building Sector? Case Study on the Construction of New Buildings in France

Considering the challenges that mineral and metallic resources represent for the building sector, there is a need to propose decision-support tools to building stakeholders. One of the possibilities could be to integrate an indicator of pressure on mineral resources in an absolute environmental sustainability assessment (AESA) approach, using life cycle impact assessment (LCIA) methods. This paper will analyze the existing LCIA indicators that can be used to represent the impact on mineral resources of new constructions, with a case study on new buildings in France in 2015. This analysis aims to find out whether the existing LCIA methods dealing with mineral and metallic resources issues are adapted to the specific stakes of the building sector in an AESA approach. The AESA approach considered is the one proposed by Bjørn and Hauschild. Several steps are detailed in this paper. Firstly, bibliographic research was carried out to identify existing LCIA methods related to the mineral resources. Secondly, selection criteria were defined in order to select those LCIA methods relevant for the building sector. Thirdly, the scope of the case study was defined and its inventory analysis was conducted using the Ecoinvent 3.5 database, selecting only the mineral and metallic input flows. Finally, the comparison between the inventory of mineral and metallic flows issued from the inventory analysis and the substances considered in the selected LCIA methods was effected. The results show that none of the existing LCIA methods are compatible with the aim of developing an LCIA indicator for mineral and metallic resources that is compatible with an AESA approach, in particular for the building sector.

Problematic consequences of the inclusion of capital goods inventory data in Environmental Product Declarations

PurposeA recent update to the Product Category Rules (PCRs) for Construction Products (of the International EPD System) has triggered a methodological issue for owners and users of Environmental Product Declarations (EPDs). The updated PCR has led to capital goods data being implicitly included in the Life Cycle Inventory (LCI) of EPDs. This paper critically examines the role of capital goods in EPDs and establishes major shortcomings in the current methodology, LCI datasets and interpretation.MethodsTo evaluate the role of capital goods in EPDs, this paper provides a discourse on the fundamentals of Life Cycle Assessment (LCA) methodology, scope, available LCI data and the impact of capital goods on EPD outcomes. Using the ecoinvent database, we analyse the impact of the inclusion and exclusion of capital goods in selected 38 construction products based on the EN 15804+A2 (2019) Standard. Finally, we estimate the relative contribution of capital goods to a suite of Life Cycle Impact Assessment (LCIA) indicators based on the archetypes of capital goods available in ecoinvent and apply Monte Carlo simulation to establish the range of uncertainties in the capital goods data for the selected construction products.Results and discussionOur research confirms that when capital goods are included based on currently available background LCI data, they mostly have a low effect (<10% increase) on climate change, but they can have an enormous effect (>100% increase) on abiotic depletion (minerals and metals), land use and/or human toxicity indicators. Interestingly, when looking further into the ecoinvent capital goods LCI datasets, it becomes clear that there are inaccuracies, inconsistencies, and possibly incorrect estimates of capital goods and infrastructure data. These findings raise questions about the suitability of the underlying LCI background data and whether non-attributable capital goods should be allowed to define EPD outcomes.ConclusionThe requirement for the inclusion of capital goods leads to a major conundrum for LCA practitioners. It is suggested that capital goods be excluded until there is better refinement and improvement of the quality of LCI datasets and EPD programs provide clearer guidance on dealing with capital goods. Alternatively, EPDs could document transparently the inclusion or exclusion of capital goods, so that there is a clear separation of the effects of capital goods on LCIA indicators.

Characterizing human health damage from ionizing radiation in life cycle assessment

PurposeAlthough a wide number of industrial processes routinely release radionuclides into the environment, the resulting potential impacts on human health have been largely overlooked in life cycle assessment (LCA). As part of the Life Cycle Initiative project on Global Guidance for Life Cycle Impact Assessment Indicators and Methods (GLAM), we aim to develop a consensus-based source-to-damage framework and factors for characterizing human health damage from ionizing radiation in LCA.MethodsOur framework comprises four modules. The fate and exposure modules are based on UCrad, an earlier developed compartment-based environmental model for radionuclides. The focus of the present work is on the dose response and severity modules, which are based on most recent data from the International Committee on Radiological Protection and the Global Burden of Disease project series. The characterization factors are expressed in terms of DALY per kBq released.Results and discussionsWe obtain characterization factors for 115 radionuclides and 8 environmental compartments. To evaluate our approach, we compare both effect factors (combining dose response and severity) and characterization factors with those proposed in earlier studies. Our analysis demonstrates that differences are explicable by the different approaches used in the fate and exposure modelling. We also test the sensitivity of our factors to different approaches for filling data gaps, suggesting that our factors are robust. Finally, we apply our factors in an illustrative case study on rice production and consumption under various scenarios to identify dominant radionuclides and how these differ when other approaches are used.ConclusionsOur framework is aligned with widely adopted methodologies for human health impact assessment, thus enabling robust comparisons, and covers nearly all radionuclides released by anthropogenic activities, including those that may arise from disposal of nuclear waste. Our factors are readily applicable for assessing radionuclide emissions in LCA. As next step we recommend (i) incorporating decay products into the fate model and (ii) integrating a model for indoor emissions of radon and indoor exposure to naturally occurring radionuclides (NORM).

Ecotoxicity characterization of chemicals: Global recommendations and implementation in USEtox

Chemicals emitted to the environment affect ecosystem health from local to global scale, and reducing chemical impacts has become an important element of European and global sustainability efforts. The present work advances ecotoxicity characterization of chemicals in life cycle impact assessment by proposing recommendations resulting from international expert workshops and work conducted under the umbrella of the UNEP-SETAC Life Cycle Initiative in the GLAM project (Global guidance on environmental life cycle impact assessment indicators). We include specific recommendations for broadening the assessment scope through proposing to introduce additional environmental compartments beyond freshwater and related ecotoxicity indicators, as well as for adapting the ecotoxicity effect modelling approach to better reflect environmentally relevant exposure levels and including to a larger extent chronic test data. As result, we (1) propose a consistent mathematical framework for calculating freshwater ecotoxicity characterization factors and their underlying fate, exposure and effect parameters; (2) implement the framework into the USEtox scientific consensus model; (3) calculate characterization factors for chemicals reported in an inventory of a life cycle assessment case study on rice production and consumption; and (4) investigate the influence of effect data selection criteria on resulting indicator scores. Our results highlight the need for careful interpretation of life cycle assessment impact scores in light of robustness of underlying species sensitivity distributions. Next steps are to apply the recommended characterization framework in additional case studies, and to adapt it to soil, sediment and the marine environment. Our framework is applicable for evaluating chemicals in life cycle assessment, chemical and environmental footprinting, chemical substitution, risk screening, chemical prioritization, and comparison with environmental sustainability targets.

Life Cycle Assessment of Cement Production with Marble Waste Sludges.

The construction industry has a considerable environmental impact in societies, which must be controlled to achieve adequate sustainability levels. In particular, cement production contributes 5–8% of CO2 emissions worldwide, mainly from the utilization of clinker. This study applied Life Cycle Assessment (LCA) methodology to investigate the environmental impact of cement production and explore environmental improvements obtained by adding marble waste sludges in the manufacture of Portland cement. It was considered that 6–35% of the limestone required for its production could be supplied by marble waste sludge (mainly calcite), meeting the EN 197-1:2011 norm. Energy consumption and greenhouse gas (GHG) emission data were obtained from the Ecovent database using commercial LCA software. All life cycle impact assessment indicators were lower for the proposed “eco-cement” than for conventional cement, attributable to changes in the utilization of limestone and clinker. The most favorable results were achieved when marble waste sludge completely replaced limestone and was added to clinker at 35%. In comparison to conventional Portland cement production, this process reduced GHG emissions by 34%, the use of turbine waters by 60%, and the emission of particles into the atmosphere by 50%. Application of LCA methodology allowed evaluation of the environmental impact and improvements obtained with the production of a type of functional eco-cement. This approach is indispensable for evaluating the environmental benefits of using marble waste sludges in the production of cement.

Comparative Life-Cycle-Assessment analysis of three major water electrolysis technologies while applying various energy scenarios for a greener hydrogen production

In terms of the decarbonization of industry, transport, electricity generation, and buildings, the production of green hydrogen plays a major role in the strategy of the European Union and Germany. Therefore, the potential environmental impacts of a greener hydrogen production have been analysed taking the three most important water electrolysis technologies alkaline electrolysis (AEC), polymer electrolyte membrane (PEMEC), and solid oxide electrolysis cell (SOEC) into account. To depict a greener hydrogen production, different energy scenarios of Germany –2019, 2030, 2050, and RE (Renewable Energy)– with an increasing share of wind and solar energy have been considered. The study shows how the potential CO2-eq. of a greener hydrogen production change when applying the different energy scenarios for each technology. On the other hand, the study aims to compare the resulting CO2-eq. with comparative values of conventional and other hydrogen production processes for classification purposes. Moreover, the study compares the CO2-eq. results with comparative values of conventional electricity generation and conventional fuels for cars, assuming that the produced hydrogen is used for electricity generation and as a fuel for cars in order to show CO2 reduction potentials. Besides that, the study compares the Life-Cycle-Impact-Assessment (LCIA) indicators under study to show which technology is potentially the most environmentally friendly one for the respective energy scenario. In summary, it can be stated that the CO2-eq. decrease with an increasing share of wind and solar energy in the energy mix since the share of fossil energies, which are the main drivers of the CO2- eq., decline. Furthermore, the SOEC technology has the lowest CO2-eq. for the energy scenarios in 2019, 2030, and 2050. This applies to the AEC technology for the RE scenario. Regarding the comparative values of conventional and other hydrogen production processes as well as conventional alternatives, only the RE scenario with wind and solar energy provides lower results. Thus, merely the RE scenario is suitable for an environmentally friendly hydrogen production and utilization in order to reduce CO2 emissions. In addition, the SOEC technology causes the lowest potential environmental impacts for the energy scenarios in 2019 and 2030, taking all LCIA indicators into account. This applies to the PEMEC technology for the energy scenario in 2050 and the RE scenario.

A Comparative Cradle-to-Gate Life Cycle Study of Bio-Energy Feedstock from Camelina sativa, an Italian Case Study

Growing energy needs and medium-term weakening of fossil energy reserves are driving forces towards the exploitation of alternative and renewable energy sources, such as biofuels from energy crops. In recent years, Camelina sativa (L.) Crantz has been rediscovered and is gaining popularity worldwide. The present work reports the results of a study on the life cycle, from cradle-to-gate, of C. sativa oil as a raw material for the production of biofuels in northern Italy, considering two scenarios, namely, the production of biodiesel (BD) and the extraction of pure vegetable oil (PVO). The functional unit was 1 megajoule of biofuel. A life cycle impact assessment (LCIA) was calculated according to the ILCD2011 procedure. Focusing on the global warming potential, the PVO scenario performs better than the BD scenario, with around 30 g CO2eq MJ−1. The net energy ratio (NER) exceeds unity for BD (approximately 1.4) or PVO (approximately 2.5). The same general trend was recorded for all calculated LCIA indicators; the common evidence is a generalized worse performance of the BD scenario, with indicators always scoring higher than the PVO. In particular, the two human toxicity indicators—carcinogenic and fresh water—eutrophication represent a significant difference, attributable to the refining process. Uncertainty and sensitivity analyses, respectively, underline the generalized importance of agricultural performances in the field and of allocation choices. Specifically, the importance of the grain yield and seed oil content in determining the environmental performance of the two scenarios was evident. As far as allocation is concerned, mass allocation provides the most favorable results, while on the other hand, the expansion of the system was the most penalizing alternative.

Environmental Sustainability Assessment of Multi-Sectoral Energy Transformation Pathways: Methodological Approach and Case Study for Germany

In order to analyse long-term transformation pathways, energy system models generally focus on economical and technical characteristics. However, these models usually do not consider sustainability aspects such as environmental impacts. In contrast, life cycle assessment enables an extensive estimate of those impacts. Due to these complementary characteristics, the combination of energy system models and life cycle assessment thus allows comprehensive environmental sustainability assessments of technically and economically feasible energy system transformation pathways. We introduce FRITS, a FRamework for the assessment of environmental Impacts of Transformation Scenarios. FRITS links bottom-up energy system models with life cycle impact assessment indicators and quantifies the environmental impacts of transformation strategies of the entire energy system (power, heat, transport) over the transition period. We apply the framework to conduct an environmental assessment of multi-sectoral energy scenarios for Germany. Here, a ‘Target’ scenario reaching 80% reduction of energy-related direct CO2 emissions is compared with a ‘Reference’ scenario describing a less ambitious transformation pathway. The results show that compared to 2015 and the ‘Reference’ scenario, the ‘Target’ scenario performs better for most life cycle impact assessment indicators. However, the impacts of resource consumption and land use increase for the ‘Target’ scenario. These impacts are mainly caused by road passenger transport and biomass conversion.

Environmental sustainability of European production and consumption assessed against planetary boundaries

The planetary boundaries (PBs) represent a well-known concept, which helps identify whether production and consumption systems are environmentally sustainable in absolute terms, namely compared to the Earth's ecological limits and carrying capacity. In this study, the impacts of production and consumption of the European Union in 2010 were assessed by means of life cycle assessment (LCA)-based indicators and compared with the PBs. Five different perspectives were adopted for assessing the impacts: a production perspective (EU Domestic Footprint) and four distinct consumption perspectives, resulting from alternative modelling approaches including both top-down (input-output LCA) and bottom-up (process-based LCA). Life cycle impact assessment (LCIA) results were assessed against LCIA-based PBs, which adapted the PBs framework to the LCIA indicators and metrics of the Environmental Footprint method (EF). Global environmental impacts transgressed several LCIA-based PBs. When assessing the overall environmental impacts of EU consumption compared to the global LCIA-based PBs, impacts of EU consumption related to climate change, particulate matter, land use and mineral resources were close or already transgressed the global boundaries. The EU, with less than 10% of the world population, was close to transgress the global ecological limits. Moreover, when downscaling the global PBs and comparing the impacts per capita for an average EU citizen and a global one, the LCIA-PBs were significantly transgressed in many impact categories. The results are affected by uncertainty mainly due to: (a) the intrinsic uncertainties of the different LCA modelling approaches and indicators; (b) the uncertainties in estimating LCIA-based PBs, due to the difficulties in identifying limits for the Earth's processes and referring them to LCIA metrics. The results may anyway be used to define benchmarks and policy targets to ensure that consumption and production in Europe remains within safe ecological boundaries, as well as to understand the magnitude of the effort needed to reduce the impacts.

Mineral resources in life cycle impact assessment: part II\u2013 recommendations on application-dependent use of existing methods and on futuremethod development needs

PurposeAssessing impacts of abiotic resource use has been a topic ofpersistent debate among life cycle impact assessment (LCIA) method developersand a source of confusion for life cycle assessment (LCA) practitionersconsidering the different interpretations of the safeguard subject for mineralresources and the resulting variety of LCIA methods to choose from. Based on thereview and assessment of 27 existing LCIA methods, accomplished in the firstpart of this paper series (Sonderegger et al. 2020), this paper provides recommendations regarding theapplication-dependent use of existing methods and areas for future methoddevelopment.MethodWithin the “global guidance for LCIA indicators andmethods” project of the Life Cycle Initiative hosted by UN Environment,62 members of the “task force mineral resources” representingdifferent stakeholders discussed the strengths and limitations of existing LCIAmethods and developed initial conclusions. These were used by a subgroup ofeight members at the Pellston Workshop® held in Valencia, Spain, toderive recommendations on the application-dependent use and future developmentof impact assessment methods.Results and discussionFirst, the safeguard subject for mineral resources within the areaof protection (AoP) natural resources was defined. Subsequently, seven keyquestions regarding the consequences of mineral resource use were formulated,grouped into “inside-out” related questions (i.e., currentresource use leading to changes in opportunities for future users to useresources) and “outside-in” related questions (i.e., potentialrestrictions of resource availability for current resource users). Existing LCIAmethods were assigned to these questions, and seven methods(ADPultimate reserves, SOPURR,LIME2endpoint, CEENE, ADPeconomic reserves, ESSENZ, and GeoPolRisk) are recommended for use incurrent LCA studies at different levels of recommendation. All 27 identifiedLCIA methods were tested on an LCA case study of an electric vehicle, andyielded divergent results due to their modeling of impact mechanisms thataddress different questions related to mineral resource use. Besidesmethod-specific recommendations, we recommend that all methods increase thenumber of minerals covered, regularly update their characterization factors, andconsider the inclusion of secondary resources and anthropogenic stocks.Furthermore, the concept of dissipative resource use should be defined andintegrated in future method developments.ConclusionIn an international consensus-finding process, the currentchallenges of assessing impacts of resource use in LCA have been addressed bydefining the safeguard subject for mineral resources, formulating key questionsrelated to this safeguard subject, recommending existing LCIA methods inrelation to these questions, and highlighting areas for future methoddevelopment.

LCA of tomato greenhouse production using spatially differentiated life cycle impact assessment indicators: an Albanian case study.

The increasing attention to agricultural exports and sustainability issues is driving a surge of interest in the life cycle assessment (LCAs) of greenhouse crop production in Albania. Meanwhile, most of the reported agricultural LCAs tend to be generic without considering regionalized environmental sensitivities. In thisstudy, ReCiPe 2016, covering 18 midpoint indicators and 3 endpoint indicators was used to generate a full-fledged cradle-to-farm gateLCA of greenhouse tomatoes in a typical Albanian farmincludingspatial differentiation and indicators not covered by contemporary LCAs. The most important midpoint categories per 1 haidentified from foreground-background analysis were global warming (2660.4kg CO2-eq), stratospheric ozone depletion (0.0308kg CFC11-eq), particulate matter formation (7.99kgPM2.5-eq), human health and ecosystem ozone formation (8.47 and 14.95kg NOx-eq), water consumption (2293.23m3), and terrestrial acidification (42.28kg SO2-eq). The application of spatial differentiation resulted in higher impacts with about 21% for particulate matter formation, 12% for human health ozone formation, 134% for ecosystem ozone formation, 19% for terrestrial acidification, and 13% for water consumption. The impacts primarily originated from nitrogen-based fertilizer emissions and diesel fuel with the origin of the impact from nitrous oxide (N2O), ammonia volatilization (NH3), nitrogen oxides (NOx), and non-methane volatile organic compounds (NMVOCs). Water consumption was dominated by irrigation water use.Overall, at the endpoint level, 9% and 24% less cumulative damage to human health and ecosystem quality were calculated with respect to the site-generic analysis primarily from the cause-and-effect chain of water consumption (mainly lower water stress index). This affirms the importance of regional considerations in LCA calculations to reflect the impacts accordingly (i.e., the magnitude of impacts, the most relevant midpoint categories, and their relevance on endpoint level) and increase the possibility of making correct conclusions and sub-optimizations, i.e., increase the discriminating power of LCA.

Assessing the consequences of policy measures on long-term agricultural productivity – Quantification for Flanders

Abstract Policy can influence the long-term agricultural resource productivity by stimulating/discouraging farmers to apply certain land use practices (LUP), as LUPs may affect the soil organic carbon (SOC) stock, hence influencing crop productivity. We introduce six policy strategies, each characterized by its own mix of LUPs, for the Flemish agricultural sector. Three strategies reveal the impact of the Common Agricultural Policy (CAP) in the past, while others reflect the potential of the CAP and the application of compost. We use the life cycle impact assessment indicators ‘SOC change’ and ‘biomass productivity loss’, which account for the impact of LUPs on SOC and yield, to assess the effects on long-term productivity. To avoid burden shifting, also the resource footprint is calculated. Several farm management systems (FMS) are distinguished, each characterized by a specific combination of farm type, agricultural region, rotation system and manure type. The results highlight that policies such as the CAP significantly contribute to a better SOC stock and (to a lesser extent) productivity. Furthermore, applying extra compost seems to be promising: it can result in an increasing resource productivity and reduced resource footprint. It is important to consider the resource footprint as only for one strategy the resource consumption outweighs the benefit (i.e. reduction in N fertilizer) in the short or medium term, while also being beneficial in terms of resource productivity. As the results differ per FMS, a differentiated approach is advisable when specific LUPs are stimulated in the context of sustainable farming.

Contribution-based prioritization of LCI database improvements: the most important unit processes in ecoinvent

Improving the quality and quantity of unit process datasets in Life Cycle Inventory (LCI) databases affects every LCA they are used in. However, improvements in data quality and quantity are so far rather directed by the external supply of data and situation-driven requirements instead of systematic choices guided by structural dependencies in the data. Overall, the impact of current data updates on the quality of the LCI database remains unclear and maintenance efforts might be ineffective. This article analyzes how a contribution-based prioritization approach can direct LCI update efforts to datasets of key importance. A contribution-based prioritization method has been applied to version 3 of the ecoinvent database. We identified the relevance of unit processes on the basis of their relative contributions throughout each product system with respect to a broad range of Life Cycle Impact Assessment (LCIA) indicators. A novel ranking algorithm enabled the ranking of unit processes according to their impact on the LCIA results. Finally, we identified the most relevant unit processes for different sectors and geographies. The study shows that a relatively large proportion of the overall database quality is dependent on a small set of key processes. Processes related to electricity generation, waste treatment activities, and energy carrier provision (petroleum and hard coal) consistently cause large environmental impacts on all product systems. Overall, 300 datasets are causing 60% of the environmental impacts across all LCIA indicators, while only 3 datasets are causing 11% of all climate change impacts. In addition, our analysis highlights the presence and importance of central hubs, i.e., sensitive intersections in the database network, whose modification can affect a large proportion of database quality. Our study suggests that contribution-based prioritization offers important insights into the systematic and effective improvement of LCI databases. The presented list of key processes in ecoinvent version 3.1 adds a new perspective to database improvements as it allows the allocation of available resources according to the structural dependencies in the data.

Global guidance on environmental life cycle impact assessment indicators: impacts of climate change, fine particulate matter formation, water consumption and land use

Guidance is needed on best-suited indicators to quantify and monitor the man-made impacts on human health, biodiversity and resources. Therefore, the UNEP-SETAC Life Cycle Initiative initiated a global consensus process to agree on an updated overall life cycle impact assessment (LCIA) framework and to recommend a non-comprehensive list of environmental indicators and LCIA characterization factors for (1) climate change, (2) fine particulate matter impacts on human health, (3) water consumption impacts (both scarcity and human health) and 4) land use impacts on biodiversity. The consensus building process involved more than 100 world-leading scientists in task forces via multiple workshops. Results were consolidated during a 1-week Pellston Workshop™ in January 2016 leading to the following recommendations. LCIA framework: The updated LCIA framework now distinguishes between intrinsic, instrumental and cultural values, with disability-adjusted life years (DALY) to characterize damages on human health and with measures of vulnerability included to assess biodiversity loss. Climate change impacts: Two complementary climate change impact categories are recommended: (a) The global warming potential 100 years (GWP 100) represents shorter term impacts associated with rate of change and adaptation capacity, and (b) the global temperature change potential 100 years (GTP 100) characterizes the century-scale long term impacts, both including climate-carbon cycle feedbacks for all climate forcers. Fine particulate matter (PM2.5) health impacts: Recommended characterization factors (CFs) for primary and secondary (interim) PM2.5 are established, distinguishing between indoor, urban and rural archetypes. Water consumption impacts: CFs are recommended, preferably on monthly and watershed levels, for two categories: (a) The water scarcity indicator “AWARE” characterizes the potential to deprive human and ecosystems users and quantifies the relative Available WAter REmaining per area once the demand of humans and aquatic ecosystems has been met, and (b) the impact of water consumption on human health assesses the DALYs from malnutrition caused by lack of water for irrigated food production. Land use impacts: CFs representing global potential species loss from land use are proposed as interim recommendation suitable to assess biodiversity loss due to land use and land use change in LCA hotspot analyses. The recommended environmental indicators may be used to support the UN Sustainable Development Goals in order to quantify and monitor progress towards sustainable production and consumption. These indicators will be periodically updated, establishing a process for their stewardship.

Developing characterisation factors for land fragmentation impacts on biodiversity in LCA: key learnings from a sugarcane case study

Habitat change was identified by the Millennium Ecosystem Assessment as the main direct driver of biodiversity loss. However, while habitat loss is already implemented in Life Cycle Impact Assessment (LCIA) methods, the additional impact on biodiversity due to habitat fragmentation is not assessed yet. Thus, the goal of this study was to include fragmentation effects from land occupation and transformation at both midpoint and endpoint levels in LCIA. One promising metric, combining the landscape spatial configuration with species characteristics, is the metapopulation capacity λ, which can be used to rank landscapes in terms of their capacity to support viable populations spatially structured. A methodology to derive worldwide regionalised fragmentation indexes based on λ was used and combined with the Species Fragmented-Area Relationship (SFAR), which relies on λ to assess a species loss due to fragmentation. We adapted both developments to assess fragmentation impacts due to land occupation and transformation at both midpoint and endpoint levels in LCIA. An application to sugarcane production occurring in different geographical areas, more or less sensitive to land fragmentation, was performed. The comparison to other existing LCIA indicators highlighted its great potential for complementing current assessments through fragmentation effect inclusion. Last, both models were discussed through the evaluation grid used by the UNEP-SETAC land use LCIA working group for biodiversity impact assessment models. Midpoint and endpoint characterisation factors were successfully developed to include the impacts of habitat fragmentation on species in LCIA. For now, they are provided for bird species in all forest ecoregions belonging to the biodiversity hotspots. Further work is required to develop characterisation factors for all taxa and all terrestrial ecoregions.

Addressing water needs of freshwater ecosystems in life cycle impact assessment of water consumption: state of the art and applicability of ecohydrological approaches to ecosystem quality characterization

In recent history, human development overbalanced towards economic growth has often been accompanied by the degradation and reduction of freshwater resources at the expense of freshwater dependent ecosystems. For their subsistence and correct functioning, understanding environmental water requirements (EWR) represents an area of great interest for life cycle impact assessment (LCIA) and it has been only marginally explored. The aim of this paper is to investigate how this concept has evolved in ecological and hydrological literature and how it can be better integrated in LCIA, to identify potential options for improvement of LCIA indicators in the short, mid and long term. To address the limitations of existing LCIA approaches in modelling EWR, four families of EWR methods have been reviewed, namely hydrological, hydraulic, habitat simulation and holistic methods. Based on existing scientific literature and their broad application, 24 methods have been selected and their suitability to be adopted in LCIA has been evaluated against nine criteria, with regard to data management issues, accuracy, scientific robustness, and potential for future development. A semi-quantitative performance score has been subsequently assigned for each criterion, showing the main strengths and weaknesses of selected methods. The underlying rationale of the chosen approaches is markedly different, likewise the input information needed and results applicability. Hydrological methods are well suited for the development of global models and they are the only ones currently considered in LCIA, although their applicability remains limited to water stress indicators. Habitat modelling is identified as an essential step for the development of mechanistic LCIA models and endpoint indicators. In this respect, hydraulic, habitat simulation and holistic methods are fit for the purpose. However, habitat simulation methods represent the best compromise between scientific robustness and applicability in LCIA. For this reason, a conceptual framework for the development of habitat-based characterization factors has been proposed. Among the evaluated habitat simulation methods, ESTIMHAB showed the best performance and was the method retained for the development of an LCIA model that will assess the consequences of water consumption on stream ecosystems. This study identifies the advantages of specific modelling approaches for the assessment of water requirements for ecosystems. Selected methods could support the development of LCIA models at different levels. In the short-term for improving environmental relevance of water stress indicators, and in the mid/long-term to build up midpoint habitat indicators relating water needs of ecosystems with new endpoint metrics.

Correlations in Life Cycle Impact Assessment methods (LCIA) and indicators for construction materials: What matters?

Different Life Cycle Impact Assessment (LCIA) methods have been developed over the past twenty years. While the use of a single score indicator may, on the one hand, ease the decision making it may also induce a loss of information. On the other hand, the use of a large set of environmental indicators may increase the difficulty of decision making due to the high number of parameters. In this paper, a statistical methodology is used to identify a simplified set of environmental indicators. This methodology applies Principal Component Analysis (PCA) to five LCIA methods (CML’01, Eco-indicator99, IMPACT 2002+, ecological scarcity, EPD) using a building products database. For each method, the results show that only 4–6 dimensions are sufficient to explain at least 90–95% of the variance for each set of indicators. They refer to the following environmental themes: fossil-fuel consumption, ecotoxicity, ionising radiation, land use and mineral resources. The use of a selected set of five LCI flows is found to be as relevant as current LCIA methods from a statistical point of view. Furthermore, PCA applied to a building LCA case study shows similar trends as for the database results. Further studies are now needed to confirm these findings for going towards simplified structural relationships among LCIA indicators for building materials.

Global guidance on environmental life cycle impact assessment indicators: progress and case study

The life cycle impact assessment (LCIA) guidance flagship project of the United Nations Environment Programme (UNEP)/Society of Environmental Toxicology and Chemistry (SETAC) Life Cycle Initiative aims at providing global guidance and building scientific consensus on environmental LCIA indicators. This paper presents the progress made since 2013, preliminary results obtained for each impact category and the description of a rice life cycle assessment (LCA) case study designed to test and compare LCIA indicators. The effort has been focused in a first stage on impacts of global warming, fine particulate matter emissions, water use and land use, plus cross-cutting issues and LCA-based footprints. The paper reports the process and progress and specific results obtained in the different task forces (TFs). Additionally, a rice LCA case study common to all TF has been developed. Three distinctly different scenarios of producing and cooking rice have been defined and underlined with life cycle inventory data. These LCAs help testing impact category indicators which are being developed and/or selected in the harmonisation process. The rice LCA case study further helps to ensure the practicality of the finally recommended impact category indicators. The global warming TF concludes that analysts should explore the sensitivity of LCA results to metrics other than GWP. The particulate matter TF attained initial guidance of how to include health effects from PM2.5 exposures consistently into LCIA. The biodiversity impacts of land use TF suggests to consider complementary metrics besides species richness for assessing biodiversity loss. The water use TF is evaluating two stress-based metrics, AWaRe and an alternative indicator by a stakeholder consultation. The cross-cutting issues TF agreed upon maintaining disability-adjusted life years (DALY) as endpoint unit for the safeguard subject “human health”. The footprint TF defined main attributes that should characterise all footprint indicators. “Rice cultivation” and “cooking” stages of the rice LCA case study contribute most to the environmental impacts assessed. The results of the TF will be documented in white papers and some published in scientific journals. These white papers represent the input for the Pellston workshop™, taking place in Valencia, Spain, from 24 to 29 January 2016, where best practice, harmonised LCIA indicators and an update on the general LCIA framework will be discussed and agreed on. With the diversity in results and the multi-tier supply chains, the rice LCA case study is well suited to test candidate recommended indicators and to ensure their applicability in common LCA case studies.

Comparison of generic and product-specific Life Cycle Assessment databases: application to construction materials used in building LCA studies

The Life Cycle Assessment (LCA) has been applied in the construction sector since the 1990s and is now more and more embedded in European public policies, e.g., for Environmental Product Declaration regulation or for building labeling schemes. As far as the authors know, these initiatives mainly rely on background impact data of building products provided by different databases’ providers. The new product-specific and company-specific EPD data allow having more than one data for describing a building material. But are these new databases really displaying similar LCA results compared to generic databases? Does it depend on which impact category (e.g., global warming, acidification, toxicity) is considered? To answer these research questions, this paper assesses numerical and methodological differences of two existing LCA databases for building LCAs: the ecoinvent generic database and one Environmental Product Declaration (EPD) database developed in France. After reviewing the main assumptions of these databases, numerical values of environmental impact are compared for 28 building materials using Life Cycle Impact Assessment (LCIA) indicators of the EN 15804 standard calculated based on cradle-to-gate ecoinvent and EPD Life Cycle Inventories (LCI). Global results at the database level indicate deviations of different magnitudes depending on the LCIA indicators and the building materials. While indicators correlated to fossil fuel consumption, such as the ADP, the GWP, and the primary energy demand, exhibit a small deviation (approximately 25 %), other indicators, such as the photochemical ozone formation (POCP), radioactive waste, and ADP elements, are found to be more variable between EPD and generic data (sometimes by more than 100 %). Three indicators are found to be systematically different between EPD and generic data (i.e., the EPD value being either higher or lower for all materials). Similarly, five building materials show systematic differences for all LCIA indicators. Specific deviations for one indicator and one material are also reported. The application of the two databases on three building LCA case studies (brick, reinforced concrete, and timber frame structures) identifies deviations due to the most influential materials. Current generic and EPD databases can present very different values at the database scale which depend on the type of environmental indicator. For building LCA results, the situation is different as generally speaking a limited number of materials controlled the impacts. Finally, recommendations are presented for each environmental indicator to improve the consistency of the building assessment from generic to product- and country-specific information.