Water footprint of mediterranean dietary patterns: how influent is raw food origin? [Poster]

The type of diet consumed in a given region (how foods are combined) influences environmental impacts considering how and where foods are produced. LCA offers a global methodology to evaluate such impacts. This study focusses on freshwater consumption and the objectives are to propose a method suitable for the evaluation of the impacts of a national diet taking into account the origin of the raw food materials and to apply it in the case of Mediterranean diets. A list of 254 food items commonly consumed in France and the corresponding quantities consumed each day on average by a representative sample of French adults were derived from two national surveys conducted in 2006-2007 by the ANSES (French agency for food, environmental and occupational health safety): the EAT2 and INCA2 surveys, respectively. Corresponding raw food product amounts were computed knowing the composition of each food product and losses between national supplies and food intake. Water consumption was then obtained per raw product and per country combining data on international trade and economic data (UNComtrade and FAOStat databases) with blue water national data (Mekonnen and Hoekstra, 2011 and 2012). Finally, a freshwater ecosystem impact (FEI) was computed, as suggested by Mila I Canals (2008), taking Water Scarcity Index (WSI) data computed by Pfister (2009) as characterisation factor. Freshwater ecosystem impacts of the French diet were computed and reported on global world maps. The same scenario (same diet) was also applied with Tunisian market data to evaluate the importance of the origin of the products: it appeared that the total FEI would be 7 times higher if the products were originated from Tunisian market. Applying the method, uncertainties in raw product origin and incompatibilities with databases appeared, inducing hypotheses that are explained and discussed. Computations were made with blue water values averaged per year and per country and the pertinence of such spatial and temporal scales is discussed as well.