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Providing our society with goods and services contributes to a wide range of environmental impacts. Waste generation, emissions and the consumption of resources occur at many stages in a product''s life cycle—from raw material extraction, energy acquisition, production and manufacturing, use, reuse, recycling, through to ultimate disposal. These all contribute to impacts such as climate change, stratospheric ozone depletion, photooxidant formation (smog), eutrophication, acidification, toxicological stress on human health and ecosystems, the depletion of resources and noise—among others. The need exists to address these product-related contributions more holistically and in an integrated manner, providing complimentary insights to those of regulatory/process-oriented methodologies. A previous article (Part 1, Rebitzer et al., 2004) outlined how to define and model a product''s life cycle in current practice, as well as the methods and tools that are available for compiling the associated waste, emissions and resource consumption data into a life cycle inventory. This article highlights how practitioners and researchers from many domains have come together to provide indicators for the different impacts attributable to products in the life cycle impact assessment (LCIA) phase of life cycle assessment (LCA). [Copyright &y& Elsevier]

Chemical screening in the United States is often conducted using scoring and ranking methodologies. Linked models accounting for chemical fate, exposure, and toxicological effects are generally preferred in Europe and in product Life Cycle Assessment. For the first time, a comparison is presented in this article of two of the prominent, but structurally different methodologies adopted to help screen and rank chemicals and chemical emissions data. Results for 250 chemicals are presented, with a focus on 12 chemicals of interest in the United Nations Environment Programme’s Persistent Organic Pollutants global treaty negotiations. These results help to illustrate the significance of described structural differences and to assess the correlation between the methodologies. The scope of the comparison was restricted here to human health, although the insights would be equally useful in the context of the health of ecosystems. Illustrating the current types of chemical screening and emissions comparison approaches, the relative significance of the scenario and structural differences of the Waste Minimization Prioritization Tool (WMPT) and the Toxic Equivalency Potential (TEP) methodologies are analyzed. The WMPT facilitates comparison in terms of key physical – chemical properties. Measures for Persistence, Bioaccumulation, and Toxicity (PBT) are calculated. Each PBT measure is scored and then these scores are added to provide a single measure of relative concern. TEPs account for chemical fate, multipathway exposure, and toxicity using a model-based approach. This model structure is sometimes considered to provide a less subjective representation of environmental mechanisms, and, hence, an improved basis for screening. Nevertheless, a strong relationship exists between the two approaches and both have their limitations. [ABSTRACT FROM AUTHOR]