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Abstract: Metals are used in a variety of ways, many of which lead to dissipative releases to the environment. Such releases are relevant from both a resource use and an environmental impact perspective. We present a historical analysis of copper dissipative releases in the United States from 1975 to 2000. We situate all dissipative releases in copper''s life cycle and introduce a conceptual framework by which copper dissipative releases may be categorized in terms of intentionality of use and release. We interpret our results in the context of larger trends in production and consumption and government policies that have served as drivers of intentional copper releases from the relevant sources. Intentional copper releases are found to be both significant in quantity and highly variable. In 1975, for example, the largest source of intentional releases was from the application of copper-based pesticides, and this decreased more than 50% over the next 25years; all other sources of intentional releases increased during that period. Overall, intentional copper releases decreased by approximately 15% from 1975 to 2000. Intentional uses that are unintentionally released such as copper from roofing, increased by the same percentage. Trace contaminant sources such as fossil fuel combustion, i.e., sources where both the use and the release are unintended, increased by nearly 50%. Intentional dissipative uses are equivalent to 60% of unintentional copper dissipative releases and more than five times that from trace sources. Dissipative copper releases are revealed to be modest when compared to bulk copper flows in the economy, and we introduce a metric, the dissipation index, which may be considered an economy-wide measure of resource efficiency for a particular substance. We assess the importance of dissipative releases in the calculation of recycling rates, concluding that the inclusion of dissipation in recycling rate calculations has a small, but discernible, influence, and should be included in such calculations. [Copyright &y& Elsevier]

An editorial is presented which addresses the debate over the life cycle greenhouse gas (GHG) intensity of corn ethanol in the midwest U.S. The authors describe the Biofuel Energy Systems Simulator (BESS). They address the wider environmental effecrs of corn ethanol. They emphasize the need to reduce the carbon intensity of fuels.

This article explores time use, attitudes toward time and the generation of municipal solid waste in the U.S. Time use and perceptions of the availability of time play an important role in solid waste management. Use of time can influence waste generation at many stages in the product life cycle. Changed shopping behavior can alter waste generation in other ways, by shifting purchases from retail settings to mail order catalogs. Time factors shape the use of goods as well. The research reviewed in this paper provides some clues on the connections between time use and waste generation. The discussion in this paper is meant to demonstrate the great potential for understanding changes in the generation and recycling of household waste that time-use research may contribute.

Editorial. Focuses on how the field of industrial ecology in the United States helped in examining the use of resources in the economy and its effects on the environment. Efforts of industrial ecology to develop heuristics and indicators which will allow business and government practitioners to judge the environmental impact of their decisions; Concerns on the environmental harm posed by the mobilization of materials; Proposed solutions in industrial ecology.

The author reflects on meta-analysis in life cycle assessment (LCA). He cites the definition of meta-analysis as the techniques used to combine the results of multiple studies. He mentions the use of the technique in studies of greenhouse gas (GHG) impacts including that of the U.S. National Renewable Energy Laboratory (NREL). Also noted is the significance of the NREL studies.