Biomedical Engineering Reference
In-Depth Information
Impact coverage in LCA studies
35
Full assessment
Partial assessment
30
25
20
15
10
5
0
FIGURE 11.8
Impact categories covered by inventoried LCA studies.
evolving field, data are difficult to gather—see Section 11.2.4.2. On the other
hand, the assessment of nontoxic impacts does not require much data as
these impacts are typically caused by a limited number of substances, which
have been identified and are relatively well monitored. For ruling out the
assessment of toxicity-related impacts, many authors have argued the lack of
reliability in the obtained results. This is primarily caused by the limited cov-
erage of substances in the characterization factor databases and by the strong
dependence of the results on the choice of the characterization models.
60-63
Nevertheless, this pattern of excluding several impact categories is worrying
in the sense that such truncated LCA may be too limited to avoid any burden
shifting across impact categories. Several studies have investigated the repre-
sentativeness of stand-alone indicators such as the cumulative energy demand
(accounting for energy requirements) or the carbon footprint (accounting for
climate change impacts). Huijbregts et al.
64,65
have found significant correla-
tions between the cumulative energy demand and the total environmental bur-
den for a majority of products taken from different sectors and recommended
its use as a screening tool, particularly useful for emerging fields because of
its low data requirements, but advised against its use as a stand-alone indica-
tor because of the too high uncertainties from nonfossil-energy-related emis-
sions and land use. Laurent et al.
66
have demonstrated the limitations of the
carbon footprint to account for the entire environmental burden, particularly
