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Purpose: 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. Methods: 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. Results and discussion: 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. Conclusions: 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.

Pesticides are applied to agricultural fields to optimise crop yield and their global use is substantial. Their consideration in life cycle assessment (LCA) is affected by important inconsistencies between the emission inventory and impact assessment phases of LCA. A clear definition of the delineation between the product system model (life cycle inventory-LCI, technosphere) and the natural environment (life cycle impact assessment-LCIA, ecosphere) is missing and could be established via consensus building. A workshop held in 2013 in Glasgow, UK, had the goal of establishing consensus and creating clear guidelines in the following topics: (1) boundary between emission inventory and impact characterisation model, (2) spatial dimensions and the time periods assumed for the application of substances to open agricultural fields or in greenhouses and (3) emissions to the natural environment and their potential impacts. More than 30 specialists in agrifood LCI, LCIA, risk assessment and ecotoxicology, representing industry, government and academia from 15 countries and four continents, met to discuss and reach consensus. The resulting guidelines target LCA practitioners, data (base) and characterisation method developers, and decision makers. The focus was on defining a clear interface between LCI and LCIA, capable of supporting any goal and scope requirements while avoiding double counting or exclusion of important emission flows/impacts. Consensus was reached accordingly on distinct sets of recommendations for LCI and LCIA, respectively, recommending, for example, that buffer zones should be considered as part of the crop production system and the change in yield be considered. While the spatial dimensions of the field were not fixed, the temporal boundary between dynamic LCI fate modelling and steady-state LCIA fate modelling needs to be defined. For pesticide application, the inventory should report pesticide identification, crop, mass applied per active ingredient, application method or formulation type, presence of buffer zones, location/country, application time before harvest and crop growth stage during application, adherence with Good Agricultural Practice, and whether the field is considered part of the technosphere or the ecosphere. Additionally, emission fractions to environmental media on-field and off-field should be reported. For LCIA, the directly concerned impact categories and a list of relevant fate and exposure processes were identified. Next steps were identified: (1) establishing default emission fractions to environmental media for integration into LCI databases and (2) interaction among impact model developers to extend current methods with new elements/processes mentioned in the recommendations.

Purpose: Regionalised characterisation factors (CFs) for watersheds around the world are available to assess water-use-related environmental impacts. The main problem with using the watershed regionalisation level arises when a single CF is generated for large watersheds in countries where water availability and demand are not uniform. Additionally, water availability and use vary over time because of the effects of climate change and changing human lifestyles. These two factors are currently not taken into account in CFs, but should be included for the sake of the accuracy of LCA results. The aim of this research was to provide water stress index CFs at the sub-watershed spatial level for three temporal scenarios (present, short-term future and mid-term future) for Spain (Southern Europe), a country with considerably variability in water availability that is especially vulnerable to climate change effects. Methods: CFs were calculated following the water stress index (WSI) definition of Pfister et al. (2009). The WSI was calculated on a yearly basis for 117 sub-watersheds - compared to 56 regionalisation units provided in the original method - and for (i) the current situation: current water use and availability; (ii) short-term future: projections for 2015; and (iii) mid-term future: projections for 2030. The uncertainties of the CFs were calculated for each sub-watershed. Results and discussion: Temporal trend analysis of the CFs showed a general relaxation of water stress over the short-term when compared to the current situation, followed by a new increase. Major differences were noticed in the WSIs calculated by Pfister et al. (2009) using global data and maps and the WSIs calculated in this study using national and regional data. The WSIs under consideration of uncertainty were higher than the deterministic result for intermediate WSIs. Conclusions and outlook: The CFs generated are useful compared with the CFs previously available because they improve evaluation of the water-use-related impacts of present and future technologies with the life cycle stages located in Spain. We encourage LCA developers to update WSIs for other countries using information at the national level that is usually freely accessible. / Dans l'Analyse de Cycle de Vie (ACV), il y a des facteurs de caractérisation (FC) à l'échelle du bassin-versant pour le monde entier et basés sur des données des années 1990. Dans ce travail, des facteurs de caractérisation de stress hydrique à l'échelle du sous-bassin versant pour trois scénarios temporels (présent, futur à court terme et futur à moyen terme) ont été développés pour l'Espagne.

Mc Corskey and al, 1977 have shown there is a link between a high aversion to oral communication and a lower self-esteem. We investigate if the Leviathan model which considers agents gossiping and having an opinion of each other (Deffuant et al 2013) is able to reproduce such a correlation. Our virtual agents form their opinions in face-to-face meetings. During these meetings, they act in self-defence applying vanity, and influence each other. They also gossip about their peers. In direct meeting and gossiping, a highly valued speaker compared to listener's self-opinion is more influential. The vanity impact depends on the distance between one's opinion of one self and the opinion conveyed by the speaker. Listeners felt held in low esteem sanction their speakers by decreasing their opinion of them. Those felt held in high esteem reward them by increasing their opinion of them. We modified the probability to talk of agents to consider a heterogeneous one: static depending on the agent itself, or dynamic depending on her self-esteem. The simplest law to obtain a heterogeneous probability to talk is sufficient to reproduce our search correlation. However, we also discover that the model argue it is possible to have a higher self-esteem for someone talking less than the others in some circumstances.