Introduction Existing product Life Cycle Assessments (LCA’s) on offset printed matter all point at paper as the overall dominating contributor to the impacts from the life-cycle of this category of products. This dominating role of paper is primarily founded in the energy-related impact categories global warming, acidification and nutrification. The studies focus on energy consumption including the emissions and impact categories related to energy. The chemical-related impact categories comprising ecotoxicity and human toxicity are not included at all or only to a limited degree. In this paper we include these chemical-related impact categories by making use of some of the newest knowledge about emissions from the production at the printing industry combined with knowledge about the composition of the printing materials used during the production of offset printed matter. This paper is based on the dissertation “Assessment of chemical emissions in life cycle impact assessment” (Larsen 2004) and the paper “Life-cycle assessment of offset printed matter with EDIP97 – how important are emissions of chemicals? “ (Larsen et al. 2009). Goal and scope The goal of the study is to identify the distribution of potential environmental impacts and consumption of resources along the life cycle of a generic printed matter produced on a model sheet feed offset printing industry in Europe. Main activities at all stages in the life cycle are covered. However special focus is on the production stage but upstream emissions assessed to be of possible significant importance are included (e.g. estimated emissions from pigment production) or handled in the sensitivity analysis. The functional unit is 1 ton of sheet feed offset produced printed matter, i.e. printed communication covering books, pamphlets etc. As time scope for the production stage 1990 – 2002 is chosen and as technological scope mainly modern technology (not state-of-the-art) used at least in Northern Europe is used. Marginal approaches are used for production of electricity (natural gas) and paper production (virgin fibres) as the main approach i.e. in the reference scenario. In all other cases an average approach is used. The consumption of raw materials at the model printing industry is mainly based on average values for 10 – 70 Swedish and Danish offset printing industries. The range in the consumption of the most important raw materials is typically well below or just above a factor of about 10. Method The EDIP97 LCA method is used. The impact assessment comprises classification, characterisation, normalisation and weighting. Danish/global normalisation references and weighting factors are used in the reference scenario and European/global ones are used for sensitivity analysis. The weighting factors for the impact categories are based on political reduction targets. Conlusion The distribution of potential environmental impacts along the life cycle of a generic printed matter produced on a model sheet feed offset printing industry in Europe has been identified and shown in Figure 1 (grey bars). The effect of including the chemical related impact categories is substantial as shown in Figure 1 (black bars), e.g. the importance of paper is reduced from 67% to 31% and the importance of printing increased from 10% to 41%. Sensitivity analysis including e.g. alternative normalisation references and alternative paper disposals (land fill), does not change the overall conclusion significantly. Furthermore, the case study shows that, even though this is a special case where the potential fate and toxicity of relatively many of the chemical emissions are known, making it possible to characterize or exclude them as potential significant contributing, only 25% - 37% of the total number of emissions is characterized. For many of the non-characterized emissions sufficient data to estimate characterisation factors do not exist. Depending on the scope, this fact seems to be of general validity in LCA studies – at least for those including many chemical emissions like studies on all types of printed matter and textiles – and this weakens the credibility of the results. Possible impacts due to (accumulated) additives and/or impurities in recycled materials like paper is not included in this study. Taking these issues into account will most probably increase the importance of the chemical related impact categories in the life cycle of printed matter. References Larsen HF, Hansen MS, Hauschild M (2009). Life-cycle assessment of offset printed matter with EDIP97 – how important are emissions of chemicals? J Clean Prod 17, 115 – 128. Larsen HF (2004). Assessment of chemical emissions in life cycle impact assessment - focus on low substance data availability and ecotoxicity effect indicators. Ph.D. Thesis, October 2004. Department of Manufacturing, Engineering and Management. Technical University of Denmark. http://www.tempo.ipl.dtu.dk/ipl/upload/publ/PhD-thesis-rev.pdf Figure 1 Comparison of weighted LCA profiles with or without chemical related impact categories included (percentage of total, milli-person-equivalents-targeted, mPET). The avoided energy consumptions and emissions due to incineration and recycling of paper are allocated to “Paper (net)”.
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