5. Conclusion

The aim of this article is to present a very specific stage in LCA: the evaluation of potential impacts. To this end, a set of consensual characterization methods is provided. An attempt has also been made to highlight the major difficulties of impact analysis:

• the complexity of impact mechanisms;

• uncertainty about impact assessment ;

• finally, the difficulty of correctly aggregating impacts.

This third stage of LCA is the most delicate to carry out. This presentation highlights the need to develop more accurate and robust characterization models, which will improve the reliability of LCA. The development of a suitable methodology is currently one of the major areas of LCA research.