Mark Goedkoop

Identifying best existing practice for characterization modeling in life cycle impact assessment

PurposeLife cycle impact assessment (LCIA) is a field of active development. The last decade has seen prolific publication of new impact assessment methods covering many different impact categories and providing characterization factors that often deviate from each other for the same substance and impact. The LCA standard ISO 14044 is rather general and unspecific in its requirements and offers little help to the LCA practitioner who needs to make a choice. With the aim to identify the best among existing characterization models and provide recommendations to the LCA practitioner, a study was performed for the Joint Research Centre of the European Commission (JRC).MethodsExisting LCIA methods were collected and their individual characterization models identified at both midpoint and endpoint levels and supplemented with other environmental models of potential use for LCIA. No new developments of characterization models or factors were done in the project. From a total of 156 models, 91 were short listed as possible candidates for a recommendation within their impact category. Criteria were developed for analyzing the models within each impact category. The criteria addressed both scientific qualities and stakeholder acceptance. The criteria were reviewed by external experts and stakeholders and applied in a comprehensive analysis of the short-listed characterization models (the total number of criteria varied between 35 and 50 per impact category). For each impact category, the analysis concluded with identification of the best among the existing characterization models. If the identified model was of sufficient quality, it was recommended by the JRC. Analysis and recommendation process involved hearing of both scientific experts and stakeholders.Results and recommendationsRecommendations were developed for 14 impact categories at midpoint level, and among these recommendations, three were classified as “satisfactory” while ten were “in need of some improvements” and one was so weak that it has “to be applied with caution.” For some of the impact categories, the classification of the recommended model varied with the type of substance. At endpoint level, recommendations were only found relevant for three impact categories. For the rest, the quality of the existing methods was too weak, and the methods that came out best in the analysis were classified as “interim,” i.e., not recommended by the JRC but suitable to provide an initial basis for further development.Discussion, conclusions, and outlookThe level of characterization modeling at midpoint level has improved considerably over the last decade and now also considers important aspects like geographical differentiation and combination of midpoint and endpoint characterization, although the latter is in clear need for further development. With the realization of the potential importance of geographical differentiation comes the need for characterization models that are able to produce characterization factors that are representative for different continents and still support aggregation of impact scores over the whole life cycle. For the impact categories human toxicity and ecotoxicity, we are now able to recommend a model, but the number of chemical substances in common use is so high that there is a need to address the substance data shortage and calculate characterization factors for many new substances. Another unresolved issue is the need for quantitative information about the uncertainties that accompany the characterization factors. This is still only adequately addressed for one or two impact categories at midpoint, and this should be a focus point in future research. The dynamic character of LCIA research means that what is best practice will change quickly in time. The characterization methods presented in this paper represent what was best practice in 2008–2009.

The LCIA midpoint-damage framework of the UNEP/SETAC life cycle initiative

Background, Aims and ScopeLife Cycle Impact Assessment (LCIA) methods can be grouped into two families: classical methods determining impact category indicators at an intermediate position of the impact pathways (e.g. ozone depletion potentials) and damage-oriented methods aiming at more easily interpretable results in the form of damage indicators at the level of the ultimate societal concern (e.g. human health damage). The Life Cycle Initiative, a joint project between UNEP1 and SETAC2, proposes a comprehensive LCA framework to combine these families of methods. The new framework takes a world-wide perspective, so that LCA will progress towards a tool meeting the needs of both developing and developed countries. By a more precise and broadly agreed description of main framework elements, the Life Cycle Initiative expects to provide a common basis for the further development of mutually consistent impact assessment methods.Main FeaturesInputs to the LCIA midpoint-damage framework are results of Life Cycle Inventory analyses (LCI). Impact pathways connect the LCI results to the midpoint impact categories with the corresponding indicators, as well as to the damage categories at the level of damages to human health, natural environment, natural resources and man-made environment, via damage indicators. Mid-point impact categories simplify the quantification of these impact pathways where various types of emissions or extractions can be aggregated due to their comparable impact mechanisms. Depending on the available scientific information, impact pathways may be further described up to the level of damage categories by quantitative models, observed pathways or merely by qualitative statements. In the latter case, quantitative modelling may stop at mid-point. A given type of emission may exert damaging effects on multiple damage categories, so that a corresponding number of impact pathways is required. Correspondingly, a given damage category may be affected jointly by various types of emissions or extractions. It is therefore an important task of the Life Cycle Initiative to carefully select damage indicators. The content of the midpoint and of the damage categories is clearly defined, and proposals are made on how to express the extent of environmental damage by suitable indicator quantities.Conclusions and OutlookThe present framework will offer the practitioner the choice to use either midpoint or damage indicators, depending on modelling uncertainty and increase in results interpretability. Due to the collaboration of acknowledged specialists in environmental processes and LCIA around the globe, it is expected that - after a few years of effort - the task forces of the Life Cycle Initiative will provide consistent and operational sets of methods and factors for LCIA in the future.

The ECO-indicator 98 explained

The Eco-Indicator 98 project aims at a complete revision of the Eco-Indicator 95 methodology. Like its predecessor, the target is to develop single scores for designers. The method now includes resources and land use. Important improvements are: the use of fate analysis, the much better definition of the damage categories concerned with human health and ecosystem health, using the PAF (Potentially Affected Fraction) and DALY (Disability Adjusted Life Years) concept, and a completely new approach to modelling resources and land use. Perhaps the most fundamental improvement is the management system for value choices. The result of this management system is that there will be three instead of one indicator. Each version is based on a different cultural perspective. The method should be updated continuously. It is proposed to set up an independent organisation to guide this future development.

Principles for life cycle inventories of land use on a global scale

PurposeTo assess the diverse environmental impacts of land use, a standardization of quantifying land use elementary flows is needed in life cycle assessment (LCA). The purpose of this paper is to propose how to standardize the land use classification and how to regionalize land use elementary flows.Materials and methodsIn life cycle inventories, land occupation and transformation are elementary flows providing relevant information on the type and location of land use for land use impact assessment. To find a suitable land use classification system for LCA, existing global land cover classification systems and global approaches to define biogeographical regions are reviewed.Results and discussionA new multi-level classification of land use is presented. It consists of four levels of detail ranging from very general global land cover classes to more refined categories and very specific categories indicating land use intensities. Regionalization is built on five levels, first distinguishing between terrestrial, freshwater, and marine biomes and further specifying climatic regions, specific biomes, ecoregions and finally indicating the exact geo-referenced information of land use. Current land use inventories and impact assessment methods do not always match and hinder a comprehensive assessment of land use impact. A standardized definition of land use types and geographic location helps to overcome this gap and provides the opportunity to test the optimal resolution of land cover types and regionalization for each impact pathway.Conclusions and recommendationThe presented approach provides the necessary flexibility to providers of inventories and developers of impact assessment methods. To simplify inventories and impact assessment methods of land use, we need to find archetypical situations across impact pathways, land use types and regions, and aggregate inventory entries and methods accordingly.

Ore Grade Decrease As Life Cycle Impact Indicator for Metal Scarcity: The Case of Copper

In the life cycle assessment (LCA) of products, the increasing scarcity of metal resources is currently addressed in a preliminary way. Here, we propose a new method on the basis of global ore grade information to assess the importance of the extraction of metal resources in the life cycle of products. It is shown how characterization factors, reflecting the decrease in ore grade due to an increase in metal extraction, can be derived from cumulative ore grade-tonnage relationships. CFs were derived for three different types of copper deposits (porphyry, sediment-hosted, and volcanogenic massive sulfide). We tested the influence of the CF model (marginal vs average), mathematical distribution (loglogistic vs loglinear), and reserve estimate (ultimate reserve vs reserve base). For the marginal CFs, the statistical distribution choice and the estimate of the copper reserves introduce a difference of a factor of 1.0-5.0 and a factor of 1.2-1.7, respectively. For the average CFs, the differences are larger for these two choices, i.e. respectively a factor of 5.7-43 and a factor of 2.1-3.8. Comparing the marginal CFs with the average CFs, the differences are higher (a factor 1.7-94). This paper demonstrates that cumulative grade-tonnage relationships for metal extraction can be used in LCA to assess the relative importance of metal extractions.

Surplus Ore Potential as a Scarcity Indicator for Resource Extraction

Summary The importance of increase in the scarcity of resources can be assessed using different approaches. Here, we propose a method that is based on the amount of extra ore mined to assess the importance of the extraction of resources. The surplus ore potential (SOP) indicator quantifies the extra amount of ore mined per additional unit of resource extracted by applying log-logistic cumulative grade-tonnage relationships and reserve estimates. We derived SOPs for 18 resources (17 metals including uranium and phosphorus) with 5 orders of magnitude difference (between 4.1 × 10−1 kilograms [kg] of extra ore per kg of manganese extracted and 5.5 × 104 kg of extra ore per kg of gold extracted). The sensitivity of the SOP values to the choice of reserve estimates (reserves vs. ultimate recoverable resource) are within a factor of 3 of each other. Combining the SOP values with the 2012 global extraction rates of these 18 resources resulted in a 236 to 372 kgore/capita surplus ore extracted. Iron, phosphorus, copper, gold, and aluminium were the largest contributors. The large variation in SOP values we observed between resources emphasizes the potential relevance of including resource-specific SOP values to assess the contribution to resource scarcity by specific products and technologies.

Stakeholder Consultation: What do Decision Makers in Public Policy and Industry Want to Know Regarding Abiotic Resource Use?

There is no agreement on what the issue of concern is regarding resource use. A stakeholder consultation was carried out in order to clarify this issue. The objective was to identify decision contexts in which stakeholders would use an indicator related to resource use, and what such indicator should express. Industry representatives were interested in the short term economic consequences of depleting resources whereas policy makers were more concerned with the robustness and reliability of the indicator over a longer time horizon. Some of the aspects the indicator should cover include availability, effort increase, substitution, and societal value. The stakeholder consultation resulted in the selection of three indicators for mineral resources and two for fossil using different time horizons; the short term perspective prioritises political constraints, the midterm focuses on the increase in effort while the long term focuses on overall availability.

Addressing land use and ecotoxicological impacts in Life cycle Assessments of food production technologies

Abstract: Effects of land use and ecotoxicity are not commonly addressed in Life Cycle Assessment on agricultural food production, due to the expected high level of uncertainties in the impact assessment and a lack of available inventory data. This chapter provides an overview of the cause–effect pathways related to the release of toxic chemicals and physical land use practices caused by food production practices. It also discusses the background and application of several Life Cycle Impact Assessment methods that produce so-called Characterization Factors to quantify the environmental effects of the agricultural activity occurring along the cause–effect pathways. Particular attention is paid to advances in the data and modelling of ecotoxicological and land use impacts that resulted in the development of a consensus model to calculate characterization factors for aquatic ecotoxicity and several models to calculate characterization factors for land use. Finally, for both ecotoxicity and land use modelling, a number of uncertainties are discussed and several requirements for improvement are proposed.

In response to “Criteria for the evaluation of life cycle assessment software packages and life cycle inventory data with application to concrete” by Seto et al. (2016)

This journal features a review of LCA software by Seto et al. (2016). After discussion with the Editors in Chief and the Submission Editor on the merits of this article, I would like to share some thoughts. This is not because I represent a company that is scoring marginally lower in the final result, but rather because this type of research should have been done so much better. I also want to support the tools that get a very low score, as I believe this is not a full representation of their merits. See this as an invitation to researchers to improve on this important topic.

Declaration of concern—an unambiguous rebuttal of the LEO-SCS-002 draft standard

Christoph Koffler & Jon Dettling & Cashion East & Matthias Finkbeiner & Sergio F. Galeano & Roland Geyer & Mark J. Goedkoop & Troy R. Hawkins & Connie D. Hensler & Arpad Horvath & Sebastien Humbert & Scott M. Kaufman & Amy E. Landis & Lise Laurin & Pascal Lesage & Manuele Margni & Ken Martchek & H. Scott Matthews & Jamie K. Meil & Gregory Norris & Rita C. Schenk & Thomas P. Seager & Maureen Sertich & Greg Thoma & Casey Wagner