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                                    directly on  value of statistical life (VSL).  Additionally, due  to the  existence of
                                    internationally accepted damage indicators by the  World Health  Organization
                                    (WHO) in the form of disability adjusted life years (DALY) (Murray and Lopez,
                                    1996; Hofstetter, 1998) and YOLL (Meyerhofer et al., 1998), other types of weight-
                                    ing across the different damage endpoints are available.
                                       Thus, in the case of damages that cause morbidity, the decision-maker must
                                    select among the assessment by  DALY or physical impact parameters, for
                                    instance, emergency room visits, asthma attacks, restrictive activity days, etc. For
                                    cancer, a selection must be made among DALY, YOLL and the physical impact
                                    parameter cases of cancer. In the case of morbidity, the choice is among DALY,
                                    YOLL and the physical impact parameter cases of death. Finally, in the case of
                                    site-specific assessment, individual risk can be evaluated. These different weight-
                                    ing options are summarized for the decision-maker in the first table which forms
                                    part of Figure 6.9, named weighting of impacts, in which all together four decision
                                    tables relevant for weighting and aggregation are presented.  Two other tables
                                    concern the discount rate for monetization and the cultural theory for DALY, and
                                    the last one concerns decisions related to the aggregation of damages. In this
                                    figure, default selections are presented as an illustration of a typical case for
                                    study of environmental damage estimations in industrial process chains.
                                       In the table for the weighting of impacts, one entry must be made for each
                                    damage class. These damage classes are the manmade environment, natural envi-
                                    ronment and human health AoPs, as well as all the so-called global indicators such
                                    as GWP and ODP that could be related to the life support functions and resources
                                    sub-AoPs if resource depletion is considered an environmental problem (see Figure
                                    6.9).
                                       Human health is divided into morbidity, cancer and mortality. In principle, the
                                    monetization can be done for all the damage classes, either by damages or abatement
                                    costs. DALY can only be used for the damages to human health. Although no more
                                    than the preferred option must be selected for monetization and DALY, in the case
                                    of using physical impact parameters the selected parameters should be mentioned
                                    here. For the monetization a discount rate must be defined. Although in principle
                                    any rate can be chosen, here 0, 3 and 10% are proposed according to the standard
                                    values used in the ExternE project (EC 1995). In the case of using DALY, one
                                    cultural perspective must be selected. According to Hofstetter (1998), three arche-
                                    types represent human socioeconomic perceptions quite well: hierarchist, egalitarian
                                    and individualist.
                                       Finally, it must be decided in which way the damage classes are aggregated. Of
                                    course this is only possible if the classes have the same weighting unit, e.g., monetary
                                    values or DALYs. In principle, two options for aggregation exist. One option is to
                                    aggregate directly in the damage matrix, called intermediate aggregation, which is
                                    less laborious due to fewer matrix operations. The other option is to undertake a
                                    final aggregation reducing the number of components in the damage profile, which
                                    makes the steps more transparent but risks confusion. In any case, the final result
                                    will be the same. Also, according to certain criteria, groups (for instance, AoPs),
                                    can be created to show unity.




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