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6.2 CHALLENGES AND STRATEGY FOR A COMBINED
FRAMEWORK OF LIFE-CYCLE AND RISK ASSESSMENT

The bases of life-cycle inventories are the emissions of pollutants and the consump-
tion of resources. In this methodology, the focus is on pollutant emissions and the
damages that they may cause. After their emission, pollutants are transported through
the environment and cause a concentration increase. On the pathway they then can
affect sensible receptors, such as humans, and may produce damages. The receptor
density clearly depends on local or regional geographic characteristics for nonglobal
impact categories. These environmental damages can be evaluated and aggregated
according to socioeconomic evaluation patterns as indicators or as external costs.
The methodology makes a step out of the LCA framework and integrates other
environmental tools, according to the idea of CHAINET (1998). Such a methodology
is confronted with the following special challenges:

1. Consider each process or at least the main ones.
2. Find a compromise between accuracy and practicability.
3. Apply the damage functions as far as possible to the emissions in their
respective continent, region or location.
4. Aggregate the damages by economic evaluation or other forms of weight-
ing to a small number of indicators.
5. Show transparency; analyze uncertainties and sensitivity.

First, a general strategy is necessary with regard to the environmental damage
estimations for industrial processes. This strategy includes an approach to make the
methodology more practicable. Starting with a conventional life-cycle inventory
(LCI), such a strategy can be described as:

1. Creating an algorithm to consider site-specific aspects
2. Calculating the potential impact score
3. Estimating global damages by the best available midpoint indicators
4. Determining main media, pollutants and processes
5. Using fate models to obtain the concentration increment in the respective
regions
6. Relating increments with dose– and exposure–response functions and
receptors
7. Disposing of methods for aggregation by accepted weighting schemes
8. Relating to other environmental management tools

6.3 COMPARISON OF ENVIRONMENTAL RISK
ASSESSMENT AND LIFE-CYCLE ASSESSMENT

Before presenting the methodology, in this section a comparison of LCA and envi-
ronmental risk assessment (ERA), the two environmental tools that are further

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