Life Cycle Assessment - Environmental Science & Technology (ACS

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life Cycle Assessment

A SECOND OPINION

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he recent article on Life Cycle Assessment (LCA) by Mary Ann Curran (ESbT, March 1993, p. 430) provides a timely update on business and governmental initiatives to refine and apply this key tool for assessing cradle-to-grave environmental impacts of processes, products, and materials. As practitioners of LCAs involved in the Society of Environmental Toxicology and Chemistry (SETAC) and EPA’s LCA activities, we would like to offer a few observations to complement those of Curran. LCAs are costly and time-conViews are insightful commentaries on timely environmental topics, represent an author’s opinion, and do not necessarilyrepment a position of the society or editors. Contmsting views are invited. 1016 Envimn. Sci. Technol., Vol. 27, No. 6,1993

B Y ALLEN L. W H I T E KAREN SHAPIRO suming because they are inherently complex and data intensive, subject to technological change, and dependent on data which often are proprietary and inaccessible to nonindustry researchers. Without these data, the researcher conducting an LCA for public use must rely on public data sources. We faced this reality early in the “Tellus Institute Packaging Study” (I) referenced by Curran, and decided that only citable sources would be included. This experience is repeating itself in a current study of life-cycle energy impacts of solid waste systems near completion for the New York State Energy Research and Development Authority (2).Until this situation is rectified, we believe that no

alternative exists but to rely on published data sources. Otherwise, industry-sponsored studies that compare one product with another (e.g., paper versus plastic cups) are not reproducible. To routinely conduct LCAs for the hundreds of product categories and thousands of discrete products clearly would be a very costly endeavor. It is difficult to imagine the routine use of LCAs for policy or ecolabelling purposes unless major advances occur in building and maintaining current, standardized, and accessible databases. Development of these databases, a need identified in 1990 at the first SETAC workshop, clearly is within EPA’s purview. From a public policy perspective, even with improved databases, conducting LCAs for every product is hardly an efficient use of limited resources. Although it is difficult to

W13-936X/93/0927-101604.W/LlO 1993 American Chemical Society

formulate public policy for the thousands of products available in the market, it is far more feasible to formulate policies that influence the choice of materials from which those products are made. For example, energy concerns in the 1970s motivated the U.S. Bureau of Mines to sponsor studies on the energy demands of major U.S. industries. Rather than examine the energy needs for the plethora of products made from aluminum, for example, this study instead inventoried the energy required to make aluminum itself (3).This type of focus on materials can help guide product design. Neither the absence of scientific consensus on LCA methods nor the high cost of performing them is a reason to halt further applications. Methodological evolution will continue for many years. Meanwhile, technological, materials, and product choices are made every day. Short of full-blown LCAs, we believe a streamlined version of LCA may be achievable to guide industry, government. and consumers in their choices. EPA’s Pollution Prevention Division, for example, is investigating ways of introducing streamlined LCA concepts into rule making under the Clean Air Act Amendments. Similar opportunities exist for manufacturers who want to avoid unanticipated future regulatory and cost burdens as they evaluate alternative process modifications and material substitution options. Curran points to the complexity of comparing and aggregating pollutants and impacts [e.g., carcinogenic and noncarcinogenic, human health and ecological) with the goal of expressing results in a common metric. The aforementioned “Tellus Institute Packaging Study” uses a ranking system that weights pollutants based on their relative toxicity and carcinogenicity. This was an early and far from perfect attempt to address this thorny issue. We and many other researchers continue to grapple with this fundamental challenge in impact analysis. But even if one subscribes to the belief that cross-pollutant and cross-impact comparisons can never be satisfactorily resolved, the inventory phase of LCAs remains a valuable vehicle for directing attention to pollution reduction opportunities regardless of their relative h m . Finally, we would distinguish carefully between industry and government perspectives on LCAs. Within a firm, LCAs are often used to target opportunities for reducing

pollutants for which the firm is responsible under federal and state air, water, and waste regulations. In other words, the system boundaries for the firm may be defined by those pollutants and damages which enter its cost calculus. These, however, represent only a fraction of the total pollutant load-and universe of impacts-that a social accounting might encompass. This distinction is an important one and should be forthrightly discussed in presenting the results of an LCA, along with the many other assumptions underpinning the analysis. References (1) “The Tellus Institute Packaging

Study”: prepared by the Tellus Insti-

tute far the Council of Stale Governments, Lexington, KY: US. Environm e n t a l Protection Agency: New Jersey Dept. of Environmental Protection and Energy: Tellus Institute: Boston. MA, May 1992. (2) White, A. et al. “Energy Implications of Alternative Solid Waste Management Systems”: prepared by the TelIus Institute far the New York Energy Research and Development Authority: Tellus Institute: Boston. M A , sept. 1992. (31 Baltelle Columbus Laboratories. “lnterim Report on Energy Use Patterns i n Metallurgical and Nonmetallic Mineral Processing”; prepared for U.S. Bureau of Mines: Battelle Laboratories: Columbus, OH, 1975.

Allen L. White is di-

rector of the Risk Analvsis Grouo. TelIUS i;lstitute, in BOSton, MA. He holds o Ph.D. in geogmphy from Ohio S t a t e University; his research interests are in life cvcle ossessment of products and rnoterials, corpomte environmental management, and internotional environmental policy. I

,

Karen Shopiro is a

research associate at the Tellus Institute. Shefocuses on development and application of LCA and pollution prevention methodologies and has been active in the SETAC LCA n m k s h u p s . She is a member of EPA’s LCA Peer Review Group, evoluoting its LCA methodology development. She is working with EPA’s Pollution Prevention Division to consider methods of

incorporating LCA concepts in rule moking. Her M.S. degree in envimnmental health is from Howard University.

J Measurement i:

Challenges in Atmospheric Chemistry

resenting discussions on state-ofthe-art techniques and instrumentation used for atmospheric measurements, Measurement Challenges In A trnospheric Chemistry summarizes progress in a variety of areas of atmospheric research and identifies areas that should now be addressed by the research community. It provides in-depth coverage of the measurement of both aeroscls and gases and reviews tKhniques for measuring Species in the tropasphere and mesosphere. An excellent reference for atmospheric SCientiStS and an ideal intrcduction to the field for analytical and gas-phase researchers interested in atmospheric measurement.

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CONTENTS Sampl ngof SeIP(1pd l d b l l i Atmosphera Poll.tanc Aulamatpd MmLrement of Atmolpher c Trace CaIOI

Fait RerpnpChemlcal Sensors Ured for Eddy Corre ation F ux Mearurements Tmpwpnercsamp 8nq w i t h A r m f t In 5 1. MearLremenrr of Slralospherlc RCactIw

Trace carer PrOQ nq l n e Chemical Oynamlcr of Aero%ls Compo5 1 Ona AnalySk O f S8ze-SegrqatW Aerosol Samp er Mear.rsnq the Strong Atid Content O f A t m o i p h e r l ~ AP~OIC~Particles Mear.rment Cnallengesof Nitrogen Swler m the Almospnere Anal,’ cal Methods Ured to ldentlfy Nonmethane Organ c Comp.ndr n Ambient Almapneres M e a w m e n i MPthWIfOr Peraxy Rsdlcd s l n the Almospnere TlOpo5pheii~Hydroxyl Radical M e a w e m P n t Of Personal Exporum to AI, Pollution

Leonard Newrnan. Brwdnaven National

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Environ. Sci. Technol.. Val. 27,No. 6,1993 1017