Towards a common conceptual framework for chemical footprint bridging Risk Assessment and Life Cycle Assessment: Short review and way forward

Paper in proceeding, 2014

Several studies have been presented recently, applying the chemical footprint (ChF) concept trying to address a variety of questions, often, but not always, to aggregate pollution of many chemicals to one or a few indicators. Furthermore, the possiblity to link chemical pollution to the concept of planetary boundaries, e.g. through the ChF concept, has also been discussed in recent publications. While the planetary boundary concept is pointed out as very difficult for chemical pollution, because of its local or regional nature, there is a need for an integrated chemical assessment and management approach on the regional and global level. This paper provides a short review and conceptual analysis regarding ChF, and suggests a way forward towards a common science based Conceptual Framework for Chemical Footprinting methods, bridging Risk Assessment (RA) and Life Cycle Assessment (LCA) science and methods. Although varying, the approaches reviewed typically are rooted in the knowledge basis of both RA and LCA. Questions for further elaboration are, e.g.: (a) Is a ChF assigned to an object in the technosphere: point source, value chain, sector, or the whole economy, and if so, on what scale (Sub-national to Global), (b) Is a ChF assigned to an object in the biosphere: specific location, or a specific organism (man?), (c) Is the number of chemicals involved one, several, all?, (e) Are chemicals treated as individuals, or grouped, or aggregated by means of toxicity related summation (TCDD-TEQ, UseTox, else). (f) What position to indicate in the cause-effect chain: from occurrence in the technosphere, to the “n-th” order effect in the environment? (f) Are also metabolites included?, and (g) What are relevant impacts, i.e. human health, or ecosystem integrity (only), or also e.g. photo chemical oxidant formation, among others? Given the apparent versatility of the concept and its potential use in chemicals management, a substantial motive to collate the initiatives exists. A SETAC-Working group would be a functional way forward with the goal to e.g.: 1) frame the existing methodologies according to applications and 2) evaluate and fill gaps and weaknesses of proposed methodologies. Input from both the RA and LCA communities are necessary to reach sound and versatile methods which are useful for chemical risk reduction and management, and to underpin development towards the definition of a planetary boundary, or boundaries, for chemical pollution.