Page 60 - Materials Chemistry, Second Edition

The Australian environment: impact assessment in a sunburnt country

Effects – e.g. increase 47
Emissions – e.g. lead concentration of Damage – e.g. Area of Protection –
emission to air toxins, higher cancers increase e.g. human health
exposure
Figure 5.1 The Eco-indicator approach (after Udo de Haes et al. 1999).

Categories, threats to the Areas of Protection, are then defined (e.g. cancer). Damage Catego-
ries are developed from analysis of specific effects that threaten or enhance the Area of Protec-
tion, such as radiation. These effects are in turn linked to emissions, waste generation or
resource use in the life cycle inventory.
Accepting the Eco-indicator approach, ‘sustainability’ in LCA terms means maintenance,
enhancement or damage minimisation in key areas of protection. The areas identified in the
Eco-indicator best practice working group include life support and resources, ecosystem health
and human health (Udo de Haes et al. 1999). Having already introduced resources and the
distinctiveness of Australian ecosystems, we can now consider the implications of these for
impact assessment, both for land use/ecology and human health.
One important factor in Australia in relation to land use is water. Given the water-scarce
nature of much of the Australian environment, any LCA with the aim to establish the impact of
a product or service on Australian ecosystems must properly account for the inevitable competi-
tion for water within catchments. Catchments typically provide water for population settlements,
agriculture and environmental flows. Approaches to land use assessment in LCA also vary from
an index of use or conversion of land to an ‘un-natural’ use (for example, in the damage footprint
developed by Lenzen and Murray (2001)) to estimates of species loss from each incremental
change in land use (such as in the Eco-indicator 99 (Goedkoop and Spriensma 1999)). There is
also hope that some of the biodiversity metrics, such as habitat hectares, could produce measures
that are generalised enough for LCA in Australia, although this area requires development.
Many land use changes are irreversible (e.g. the destruction of native forests), and much
damage to land and water systems is derived from historical actions, both of which further
complicate land use impact assessment. Clearing of land, introduction of weed species and
feral animals, and the modification of water tables have led to some of the largest impacts on
ecosystem quality in Australia. The impacts of current production and consumption appear to
contribute little in many of these historical issues or, if so, only at the margins.
Biodiversity and ecosystem diversity are site-specific and difficult to generalise into LCA.
Many subtle management effects are important to ecosystem diversity and maintenance. These
can include diverse factors such as fire (or the lack of it), flood regimes and protection from
pests. While pressure from production and consumption of goods may affect some of these
issues (e.g. timber production will preclude fire regimes), it is almost impossible to determine
clear, generalisable links.
Turning to human health, work on the impacts of toxic substances in Australia has been
undertaken by the University of New South Wales and Mark Huijbregts at Nijmegan Univer-
sity (the Netherlands). This work has examined fate and exposure factors (how emissions of
toxins find their way into humans) and compared these to models developed for the USA and
Europe. The dryness of the Australian continent appears to reduce people’s exposure to toxic
pollutants, as water is an important transfer mechanism in their movement. The fate factors
for human exposure of substances emitted to agricultural soils are, on average, 160 times lower
than those in Western Europe, and substances emitted to air, fresh water and seawater are 20
times lower than the average (Huijbregts et al. 2003). This work has also found large uncer-
tainties in the modelling of toxic emissions in Australia.

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