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(persons.mg/m .yr/kg). It should be mentioned that the impact indicators for the
heavy metals As, Cd and Ni, as well as for benzo[a]pyrene (BaP), are supposed to
be the same as for PM . It is assumed that these substances are adsorbed on particles
2.5
of PM 2.5 and therefore behave in the same terms of fate and exposure. However, the
DALY value is specific for each substance because the dose–response and expo-
sure–response functions are substance specific as well.
The ozone value is taken as country average from Krewitt et al., (2001). The
values for nitrate and sulfate do not differ because these are secondary pollutants
for which country averages have been calculated. Only the value for the sulfate
in the first row differs slightly, due to the stack height of the MSWI (50 m), which
differs from the one of the transport processes (5 m stack height). The highest
values for the primary pollutants appear in Madrid and the lowest in the small
town of Huesca. These values are calculated according to the expression described
in Section 7.6.5 for the transfer of impact factors to other regions. In comparison
to Catalonia, Madrid is densely populated and Huesca is scarcely populated, so
these results are obvious.

7.7.6 DAMAGE PROFILE
Table 7.13 shows the damage matrix for Scenario 1 (former situation) resulting from
the multiplication of the eco-technology matrix (Table 7.11) and the damage-assign-
ing matrix (Table 7.12). If the first column is considered, the first box (the first
element of the diagonal) represents the damage for the MSWI. The second element
in the second column represents the damage for the transport in district class I B
and so on. If one leaves the diagonal, the impact of the processes at (fictitious) other
locations is shown. For example, the last element of the first column shows the
damage of the waste incinerator if it were to be located in Madrid. Of course, it
must be admitted that the impact indicator applied to this cell refers to a stack height
of 5 m (transport) rather than to 50 m (MSWI), in which the damage would be twice
as high as it is currently. Nevertheless, this provides an impressive demonstration
of the importance of spatial differentiation.
Next, the diagonal elements of the damage matrix are added to obtain the damage
profile, then the part corresponding to transport is compared with the value of the
waste incinerator. In this way the damages due to the waste incinerator and the
transport can be compared.
The most obvious result of this environmental damage estimation study for
industrial process chains is that the contribution of transport to the overall damage
increases significantly from Scenario 1 over Scenarios 2 and 3. On the one hand,
this is due to the sharp decrease of the overall damage and, on the other, the decrease
of damage due to the improvement of flue gas treatment is partly compensated for
by the additional transport processes.
From the results of all scenarios it can be seen that the ratio between the damage
due to transport and the overall damage is in the same magnitude for all chosen
indicators in this study (PE and DALY). Whether the contribution of transport to
the overall result is more significant for the population exposure or DALY in the
case of each pollutant depends on the relationship between the toxicity and the mass

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