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TABLE 3.11
European Health Damage Costs Calculated with the Uniform World Model
Cost (mU.S.$/kg
emitted Multiplier for site Multiplier for stack emissions
Pollutant pollutant) (rural ↔ urban) (height 250 ↔ 0 m, T, v )
a
CO 2.07 ? ?
NO x via Nit 1.69 × 10 4 ≈ 0.7 ↔ 1.5 ≈ 1.0
SO 2 tot 1.22 × 10 4 ≈ 0.7 ↔ 1.5 ≈ 1.0
PM 10 1.36 × 10 4 ≈ 0.3 ↔ 3 ≈ 0.6 ↔ 2.0
As 1.50 × 10 5 ≈ 0.3 ↔ 3 ≈ 0.6 ↔ 2.0
Cd 1.83 × 10 5 ≈ 0.3 ↔ 3 ≈ 0.6 ↔ 2.0
Cr 1.23 × 10 5 ≈ 0.3 ↔ 3 ≈ 0.6 ↔ 2.0
Ni 2.53 × 10 3 ≈ 0.3 ↔ 3 ≈ 0.6 ↔ 2.0
PCDD/Fs 1.63 × 10 10 ≈ 0.3 ↔ 3 ≈ 0.6 ↔ 2.0
m = 10 –3
a t= temperature; v = velocity
Source: Data taken from Rabl et al. (1998).

All this allows calculating potential impact scores, but not actual damages.
Therefore, the appropriate level of sophistication of LCIA involves quite a number
of issues. A major point concerns the extension of the characterization modeling to
include not only the effects of the substances but also their fates. Another issue
concerns a possible differentiation in space and time. Studies can include impact
models that use data at world level and do not specify time periods; in contrast,
more recent options involve spatial differentiation of impacts and distinguish
between different time periods. A further point concerns the type of modeling. More
sophisticated possibilities arise that take background levels of substances into
account and make use of nonlinear dose–response functions. An important question
here is whether these are real science-based thresholds, or whether these thresholds
are always of political origin. A further question relates to the role and practicality
of including uncertainty analysis. Although sensitivity analysis is increasingly
included in LCA studies, this is not yet the case for uncertainty analysis. Finally,
there are the questions of how to apply these different options for sophistication of
LCIA, which applications can afford to keep it simple, and for which applications
a more detailed analysis is needed (Bare et al. 1999; UNEP DITE, 2003).
The important issue of deciding the appropriate level of sophistication is typi-
cally not addressed in LCA. Often, determination of the level of sophistication is
based on considerations that may be appropriate for a scientific point of view, but
which include practical reasons for limiting sophistication (e.g., the level of funding).
A discussion of the most appropriate ways of determining sophistication will include
(Bare et al. 1999; UNEP DTIE, 2003):

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