LCA versus RA - an introduction

Risk Assessment (RA) of chemicals is an environmental management tool used to assess the risk of specific chemicals, which are harmful to man or the environment under certain circumstances of use or in certain environmental recipients. Life Cycle Assessment (LCA) or environmental assessment of products is another environmental management tool that gains more and more ground, and which is often thought of as universal due to its basic holistic philosophy. As the environmental impacts of one product can only be seen in relation to the impacts of other products providing the same functions, LCA is a comparative tool. The primary purpose of this article is to identify harmonies, discrepancies and relations between the two tools, exemplified by the risk assessment principles of the European Commission (EC) as stated in 'Technical Guidance Document' (EC, 1996) and the LCA method 'EDIP' (Environmental Design of Industrial Products) developed in Denmark (Wenzel et al., 1997), respectively. The interactions between the two tools can be viewed from two different angles: 1. As a general reflection of how the tools supplement each other in the total environmental effort. 2. As an assessment of coincidences and discrepancies in the principles of assessing the potential for ecotoxicological and toxicological effects. The aim here is to compare the two tools to each other and relate the development/use of the two tools to possibilities for integration etc. As the Techical Guidance Document (TGD) (see chapter on Principles and Methods for Hazard and Risk Assessment)focuses on an assessment of the toxicological and ecotoxicological risks, the focus of this article's comparison of assessment principles, data requirements etc. will be on the assessment of toxicity and ecotoxicity in EDIP's impact assessment methodology (see chapter on Principles and Methods for LCA). In this connection, it should be mentioned that toxicity assessments belong to a group of impacts (the local impact categories) for which there is at present no prospect of consensus either in SETAC or in ISO. This is due to the fact that the scopes of LCA do not permit a realistic assessment of actual effects (see chapter on Principles and Methods for LCA). The assessment is therefore limited to comprising potential impacts, and for local impacts in particular it can be difficult to assess the probability of the realisation of the potentials. However, several methods have been developed to assess the impact potentials within these categories (Guinée et al., 1996; Jolliet, 1994; Jolliet & Crettaz, 1996), among these EDIP (Hauschild et al., 1998a and 1998b). The assessment of impacts in the work environment in the EDIP methodology operates on another theoretical basis than the other impact categories. Therefore, the work environment will not be included in this paper even though exposures and effects in the work environment are included in TGD's assessments.