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(23-04) Comparison of a LCA and a MFA study on food consumption. Faist, Mireille*,1,2, Jungbluth, Niels1, Kytzia, Susanne2, Frischknecht, Rolf1, 1 ESU-services, Uster, Switzerland2 Swiss Federal Institute of Technology Zurich (ETHZ), Zurich, Switzerland ABSTRACT- In the past years, several studies have been analysing food consumption and its environmental effects. Some of them come to different or even contradicting conclusions. To which extent these differences can be explained by methodological differences pertaining e.g. to systems definitions or choice of indicators is the issue of this paper. It compares two recent Ph.D. projects of the Swiss food system, one using life cycle assessment (LCA) and one using an extended material flow analysis (MFA). The different scopes of the studies, data, method and indicators used as well as the results are described and analysed in the presentation. The aim of the LCA study of food is to compare the environmental impacts of different food purchasing patterns. It focusses on meat and vegetables and uses the Eco-indicator 99 impact assessment method. The aim of the MFA study is to evaluate the resource efficiency of the food system and to define scenarios improving it. It analyses the yearly sales of a Swiss regional food retailer and sets a geographical system border differentiating between the region itself and the ′hinterland′, the regions required for e.g. production of imported food. Indicators are the resources energy and land use. These two indicators grasp – directly or vicariously – the most important aspects of the food production and consumption and allow describing a large system. The comparison of both studies shows that they agree on some results, as the importance of meat consumption and greenhouse production. However, they weigh some other aspects differently, such as transports. Both studies cannot give a definitive answer in the comparison of different agricultural production techniques, as they cannot (yet) integrate important parameters as e.g. soil quality in a satisfying way. The MFA study further integrates regional aspects through the differentiation of processes of inland and ′hinterland′. Advantages and limitations of both methods for the description of food system are discussed. Key words: Life Cycle Assessment, Material Flow Analysis |
