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Perspectives in Life Cycle Impact Assessment: A Structured Approach to Combine Models of the Technosphere, Ecosphere and Valuesphere describes the relationship between subjective and objective elements in Life Cycle Impact Assessment. It suggests a new framework which will allow people to master two of the major problems associated with LCA, the difficulty of separating subjective from objective elements and the tendency for impact assessment to record `phantoms' rather than actual damages.
Perspectives in Life Cycle Impact Assessment: A Structured Approach to Combine Models of the Technosphere, Ecosphere and Valuesphere presents a proposal for a second generation framework and method for Life Cycle Impact Assessment. Many of the suggested elements are either based on other tools for environmental analysis, e.g. risk assessment, or fit in well with tools and concepts such as industrial ecology, technology assessment, or environmental impact assessment. The research presented in this book goes beyond the scope of presently used methods for Life Cycle Assessment and may stimulate new developments in a variety of areas.
The book will appeal to persons from a wide range of scientific disciplines who are interested in learning more about Life Cycle Assessment. It will be especially valuable to members of SETAC and to students and researchers in the fields of environmental impact assessment, risk assessment and industrial ecology.

Inhaltsverzeichnis

Frontmatter

1. Introduction to Life Cycle Assessment and its Positioning

Abstract
The book’s contribution is twofold: first to unveil the relationship between subjective and objective elements in Life Cycle Impact Assessment and to propose ways to deal with the natural and social science interface; and second to enhance the state-of-the art in modelling the ecosphere, i.e., to improve the predictions of impacts and other characteristics that are relevant in decision making supported by Life Cycle Assessment.
Patrick Hofstetter

2. Shift of Paradigm — Propositions — Objectives

Abstract
In Chapter 1 we situated LCA within the decision making process and in relationship to other decision support tools. LCA has been identified as only one of the perspectives that can be used when assessing human activities from an environmental perspective. There exists a large number of competing tools, each with its own characteristics, that differ from those of LCA. Therefore, LCA sensu stricto as used in this book was defined in Subsection 1.2.6. However, the two following main criticisms towards LCA have not been answered with this clarification of what LCA sensu stricto is and what it can and cannot do (see, e.g., Barnthouse et al. 1997): (1) LCA cannot strictly separate objective and subjective elements, and (2) LCA does not have an acceptable way to model impacts.
Patrick Hofstetter

3. Modelling the Valuesphere by Cultural Theory

Abstract
Chapter 2 claimed that many elements within life cycle assessment are, by their nature, subjective settings, i.e., value choices. It was stated that at the highest level at which disutility is to be measured are the safeguard subjects which themselves reflect a certain world view. This chapter explains the need for a model of the valuesphere, introduces a heuristic, and discusses its application within LCA. Section 3.1 highlights the problem at hand and specifies the requirements such a heuristic should fulfil. The chosen heuristic, called Cultural Theory, is introduced and discussed in Section 3.2. A short overview on other typologies is provided in Section 3.3 in order to position Cultural Theory. First, consequences of the use of Cultural Theory within LCA are highlighted in Section 3.4. Cultural Theory is not uncontroversial and is introduced here as just one useful heuristic and not as the key for the rationalisation of all subjective elements.
Patrick Hofstetter

4. Modelling the Ecosphere by the Structured Aggregation Procedure

Abstract
While Chapter 3 described the model of the valuesphere, this one will discuss, explore, and finally describe how the ecosphere is to be modelled. After a specification of the problem setting, we propose to model the sphere by the three different aspects ‘damage’, ‘unknown damage’ and ‘manageability’ (Section 4.2). For each of them, a separate structure will be suggested which leads through aggregation to an index (Sections 4.3 to 4.5). As already argued in Section 2.1, the ecosphere can only be modelled by assuming an underlying valuesphere. Therefore, the relevance of the three indices depends on the cultural perspective adopted. The value choices within the single indices are suggested separately for each cultural perspective. An overview of the whole structured aggregation procedure is provided in Section 4.6. The prescriptions for the final rules of composition and aggregation have to be seen as preliminary at this stage of their development. Empirical work with decision makers may well alter the results of this last step.
Patrick Hofstetter

5. DALYs — An Index for Human Health Assessment

Abstract
The structured aggregation procedure presented in Chapter 4 has been designed to measure the importance of environmental problems by three main criteria: the magnitude of damage they generate, the manageability of these damages, and the unknown damage. Suggestions for how these criteria could be operationalised and concepts for doing so have already been given in Sections 4.3 to 4.5. This chapter is limited to a further elaboration of the way the magnitude of damage to human health can be measured. It focuses exclusively on the problem of aggregating different health outcomes and introduces a health index for this purpose. This limited focus allows for going into details and looking at the problems likely to occur when the damage assessment introduced in Section 4.3 is put into practice. The same level of detail is likely to be needed when one would want to look at the criterion of manageability or develop an index for damage to ecosystem health in greater detail than has been done so far in Section 4.3. An important difference between the areas of human and ecosystem health is that, in the former, there is extensive literature available from medical science and health policy which goes back many decades, while the literature on environmental health is less comprehensive because of a more recent origin and the coverage of only a limited range of issues.
Patrick Hofstetter

6. Damage to Human Health from Environmental Chemicals that Cause Cancer

Abstract
The objective of this chapter is to demonstrate the quantitative feasibility of the framework introduced in Chapters 3 to 5, evidenced by the example of environmental chemicals causing cancer in humans. The damage to human health will be assessed by the modelling of an impact pathway starting with the fate or exposure analysis following an emission, the effect analysis following an exposure of human beings, and an analysis of the resulting diseases due to tumours. The causal relationship between emissions to air or water and damage to human health will be presented in terms of disability adjusted life years (DALYs) per kg substance emission. Further, the index for manageability will be assessed following the proposal in Section 4.5. Both, the resulting index for the magnitude of damage and the index for manageability will be derived in dependence of the cultural perspective applied, i.e., they look differently for the individualists, egalitarians, or hierarchists perspective.
Patrick Hofstetter

7. Damage to Human Health from Respiratory Effects

Abstract
The choice of impact categories for operationalisation has been justified in Subsection 4.3.6. In this chapter we operationalise the impact category ‘respiratory effects in human beings’. Effects in humans due to the different acting agents are assessed through the construction of damage factors. Damage factors are composed of the fate factors to calculate exposure due to emissions (Section 7.2), of the effect factors to determine expected effects in humans (Section 7.3), and of the disability adjusted life years lost due to the assessed effects (Section 7.4).
Patrick Hofstetter

8. Perfection of the Framework

Abstract
In this chapter, we develop further methodological elements and applications of the framework before turning to a discussion of the results and the concluding chapter. A preliminary structure for the combination and the aggregation of the submodels of the ecosphere and their indices had been suggested in Section 4.6. In Section 8.1 we will now present a graphical dominance analysis which will make it unnecessary in many product comparisons to aggregate all the indices to one overall “eco-index”. Section 8.2 will address the role of Cultural Theory in the modelling of the technosphere and show why uncertainty is reduced when the value choices are made in a coherent manner. A last section will explore the role of the framework as a meta-method within LCA and related life cycle tools (Section 8.3).
Patrick Hofstetter

9. Results and Discussion

Abstract
This discussion of results begins with another visual summary of the structure of the framework. It brings together all its elements, but is shorn of many of the details that have been discussed in earlier chapters in order to highlight its essence (Section 9.1). Then follows a discussion and comparison of the results from the two case studies of ‘carcinogenic’ and of ‘respiratory effects’ (Section 9.2). In Section 9.3, we attempt to step back somewhat from the role of author in order to look from a different point of view self-critically at the framework proposed in this book. Then follow some additional thoughts on the lack of validation and verification of the framework (Section 9.4) and the final section will focus on the consequences of using this approach as decision support.
Patrick Hofstetter

10. Conclusions

Abstract
The book’s main title ‘Perspectives in Life Cycle Impact Assessment’ had been chosen because of the many meanings in which the concept of perspectives is appearing in and made use of in this book:
  • The LCA-perspective of the world: LCA has a very special view of the world. Its aim is to reduce the environmental damages per service gained from products, i.e., to improve the environmental efficiency of the processes in the technosphere. But in trying to do so, hardly any temporal and spatial resolution is provided, i.e., past, present, and future impacts are compressed and treated as if they would occur today and spatial differentiation is avoided by assuming a unit world approximated in our case by average parameter values for the whole of Western Europe. This way of dealing with time and place enables the tool to analyse environmental interventions of product systems and their impacts over the whole product life cycle.
Patrick Hofstetter

Backmatter

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