Do Bio-Based Products Move Us Toward Sustainability? A Look at Three USEPA Case Studies

摘要

The movement to buy "environmentally-friendly" products was recently reinvigorated by the signing of the 2002 Farm Act that requires all federal agencies to give preference to products made, in whole or significant part, from bio-based material. This paper addresses the reality behind widely held beliefs regarding "green" issues, and shows bow complex it can be to choose among alternative products. Examples are presented in which the U.S. Environmental Protection Agency (USEPA) used different approaches, all based on life cycle assessment (LCA), to evaluate the environmental trade-offs of bio-based alternatives. These examples incorporate various combinations of life cycle inventory (LCI) and life cycle impact assessment (LCIA). The first example presents results of a USEPA Office of Research & Development (ORD) project called the Framework for Responsible Environmental Decision-Making (FRED). The FRED framework uses a set of impact categories in an LCIA. Motor oil, wall insulation, and asphalt coating alternatives were all studied using FRED. The second example is a pilot study in the USEPA's Environmentally Preferable Purchasing program. Using a mix of LCI and LCIA, transformer oil and hard surface cleaner alternatives were evaluated. Finally, the paper presents preliminary LCI results of another ORD effort comparing fuel additives ethanol and MTBE. These examples demonstrate that the move to bio-based products is not an across-the-board "win" for the environment. While LCAs cannot, at this time, provide a definitive answer as to theprefer-ability of bio-based products, it is the best tool to identify environmental trade-offs, thereby providing additional information to support decision-making.