Rolf Frischknecht and Olivier Jolliet, Workshop Co-Chairs
A SETAC Pellston Workshop® was held in late June 2018 in Valencia, Spain, to develop the second volume of the United Nations Environment Programme’s Life Cycle Initiative project, “Global Guidance for Life Cycle Impact Assessment Indicators and Methods.” Volume 1 of the guidance was developed after a SETAC Pellston Workshop that was held at the same venue in 2016. It identified recommendations on Life Cycle Impact Assessment (LCIA) environmental indicators and characterization factors (CFs) in the areas of climate change, human health impacts due to fine particles, impacts related to water consumption and biodiversity impacts caused by land use. The goal of the recent workshop was to reach consensus on recommended environmental indicators and CFs in the areas of human toxicity, ecotoxicity, acidification and eutrophication, soil quality and related ecosystem services, mineral resources, as well as crosscutting issues so that a total of nine impact categories are covered in the global guidance. An extensive two years of preparation preceded the workshop, which resulted in white papers on the above-mentioned new topics, as a basis for the consensus finding process and the drafting of final recommendations.
The workshop was organized collaboratively by SETAC and the Life Cycle Initiative. The workshop brought together 40 participants representing a balanced mixture of life cycle assessment (LCA) experts and domain experts, as well as LCA users from academia, business and government and non-governmental organizations. The participants were from 20 different countries representing all regions of the globe. The one-week workshop was characterized by intensive discussions as well as exchange of arguments and positions. We were pleased to witness passion but at the same time openness and fairness. Finally, supported by the Pellston process, the participants agreed on tangible and practical recommendations on environmental indicators, including substantial innovations. Volume 2 will summarize the main recommendations agreed upon, which were:
- Human toxicity. Three human toxicity indicators were recommended considering different severity for cancer, non-cancer developmental and other non-cancer effects. For human exposure, these indicators build on a matrix framework consistently coupling environmentally mediated exposures with indoor and consumer product exposures. The non-cancer indicators build on a stochastic dose–response model recommended by the World Health Organization for a 10% population response level to derive effect factors, combined with severity factors based on the latest Global Burden of Disease statistics.
- Ecotoxicity. Promising solutions were identified for harmonized assessment of ecotoxicity from chemical emissions in LCIA. The major recommendations were: 1) to consider effects of chemicals on organisms living in coastal waters, soil, freshwater and freshwater sediment; 2) to base effect modeling on most available chronic data and concentration levels close to environmental concentrations; 3) to disregard concentration reduction through bioaccumulation in exposure modeling; and 4) to consider ageing and weathering of metals in soil and freshwater sediment.
- Acidification and eutrophication. Selected indicators and CFs were recommended for freshwater eutrophication, terrestrial acidification and midpoint marine eutrophication (interim recommended for marine eutrophication endpoint, which needs further investigation). Further consensus recommendations were: 1) to use spatially explicit models with global coverage; 2) to aggregate CFs (to country or global level) using agricultural, non-agricultural or overall emissions weighting (and apply these according to goals of a study); and 3) to use existing environmental concentrations for effect modeling. These changes will move these categories towards increasing relevance of models for LCA results.
- Soil quality and related ecosystem services. It is evident that high-quality, functional soil is important for the supply of ecosystem services, such as providing biomass and regulating climate. Further, it is clear that land use and land use change are key human stressors that can affect soil quality. Therefore, it was an interim recommendation that change in soil organic carbon is used as the indicator of soil quality as it is a good integrative indicator of soil functions. It was also suggested to refine the evaluation of forestry and permanent crops in LCIA to allow for the representation of improved land management; once this is achieved, this indicator will move to full recommendation. Finally, soil loss was recommended as a separate indicator linked to natural resources to address erosion impacts.
- Mineral resources. The area of protection related to mineral resources has been defined and methods have been grouped depending on whether they assess the impacts of a product system’s resource use on the opportunities of future generations to use resources (inside-out), or resource availability for a product system (outside-in). For the inside-out perspective, abiotic depletion potential was recommended to assess the depletion of stocks. Methods to assess the consequences of a declining resource quality, to assess economic externalities and to assess resource use based on thermodynamics were interim recommendations. Methods addressing the outside-in perspective were recommended to be used as a complement to (environmental) LCA.
- Cross cutting issues. Cross-cutting issues studied included uncertainty and harmonization in LCIA. For uncertainties, it was strongly recommended to follow a tiered approach, interpreting and reporting all relevant types of uncertainty and associated variability. For harmonization, it was strongly recommended to develop a common reference nomenclature and classification system for LCI and LCIA. Further research was recommended on improving available options for the instrumental values framework and for addressing ecosystem vulnerability consistently to allow aggregation of indicator scores across all impact categories.
The second volume of LCIA Global Guidance will also provide tables of recommended CFs to operationalize the application of the recommended indicators. Further, the participants mutually agreed to seize the momentum created to install a structure within the Life Cycle Initiative providing stewardship for both recommended CFs as well as for enabling their regular update in the future. Moreover, they strongly recommended integrating the set of indicators developed for the nine impact categories into a fully consistent and comprehensive LCIA global method in the near future.
As a result of this workshop, a scientific paper is being prepared, which summarizes the main achievements and recommendations of the workshop, and the official launch of volume 2 of the “Global Guidance on LCIA” is scheduled for March 2019. This second volume will constitute a substantial step ahead for LCIA practice and will inform the identification of Product Environmental Footprints (PEFs) – a program initiated by the European Commission in an effort to directly communicate LCA information to consumers.
The results achieved during this Pellston Workshop exceeded the high expectations of the participants. It showed once again that such a science-based, consensus-finding process does not freeze scientific knowledge but rather promotes progress in science and, at the same time, fosters the practicality, stability and robustness of the recommended indicators by engaging the user community.
We thank all participants and their institutions for their invaluable contributions to the intensive but also fun and unforgettable experience. We would especially like to thank Llorenç Milà i Canals and Feng Wang from UN Environment and Tamar Schlekat and Barbara Koelman from SETAC for their ongoing, upfront and on-site support. It helped the experts to fully concentrate on content. Finally, our sincere thanks also go to the sponsors of the LCIA Global Guidance project as well as of this Pellston Workshop, i.e., the funding partners of the Life Cycle Initiative and the sponsors of this specific workshop.
Portions of this article originally appeared in the July-August Edition of LC Net and have been republished with permission.