Life cycle assessment of urban food supply: Key findings and recommendations from a French metropolitan area case study

The environmental challenges raised by urban food supply requirements must be addressed and sustainable local food policies need to be designed. For these reasons, the major areas of improvement should be identified in terms of both consumption and production. This paper aims at implementing Life Cycle Assessment (LCA) to achieve a comprehensive diagnosis of the environmental impacts of food supply at a city level, and to provide adequate recommendations on how to perform data collection. Initially designed to quantify the environmental performance of a product or service, proposals have been made to adapt LCA to city and territory scales. However, applications are still scarce, as data collection can be very resource-intensive. Most existing studies apply a top-down approach that presents a number of limitations. For example, an overly aggregated repre-sentation of the studied sectors is proposed, while mainly greenhouse gas impacts are quantified without addressing a broad coverage of environmental issues. In this paper, a bottom-up approach is adopted, where the collected data concerns a comparison between two data sources involving individual food consumption (i.e. a national and a local survey). AGRIBALYSE 3.0 database is used for life cycle inventories of food products and different methods are employed to scale up the analysis to city level. Results indicate that the main impacts arise from animal product consumption and agricultural production stages, with certain variations according to the impact category and considered food product. A comparison between national and local data on food con-sumption confirms that average national data are sufficient for an initial diagnosis. One of the next challenges will be to improve the LCA databases. Although they now include several hundred foodstuffs, they do not distinguish between alternative practices (e.g., for agricultural or retailing step) and product sources.