Life Cycle Assessment

Background

The concept of Life Cycle Assessment emerged in the 1970s as a way to assess the overall use of energy and materials by products or services, from "cradle to grave" (creation of raw materials to final disposal). Later, the method was extended to include environmental emissions to air, water, and solid waste (SETAC 1991). In 2000, the International Standards Organization (ISO) completed work on a series of standards that have become the general benchmark for the technique.

Life Cycle Assessment is divided into four basic stages:

	Defining the goal, scope and boundaries of the assessment.
	"Life Cycle inventory" (LCI) - a database of energy/materials use and emissions, relative to some "functional unit" (e.g., for a detergent, emissions per 1000 loads of laundry washed; for an automobile, emissions per 1000 person-kilometers traveled).
	"Life Cycle impact assessment" (LCIA) - translation of inventory data into potential impacts on the environment.
	"Interpretation" - sensitivity and uncertainty analyses.

Life Cycle Assessment has been used for various purposes by industry, academics, public interest groups, and government policymakers. Common uses include:

	Identifying those phases of a product's lifecycle that have the largest environmental burdens, and therefore the greatest opportunities for improvement.
	Comparing the burdens of different products that are used for the same task.
	Evaluating the influence of changes to a product, especially whether improvements in one part of a product's lifecycle could have offsetting negatives in another.
	Assessing the relative environmental burdens of different human activities (e.g., transportation, home heating/cooling, waste management).

While Life Cycle Assessment has been widely used, it continues to face challenges. First, the process is inherently complex, time consuming, and costly. It requires considerable data and relies on a variety of assumptions. Second, there are continuing questions about impact assessment, especially for "local" issues such as ecotoxicity, human health, or nutrient enrichment (eutrophication). Finally, communicating the results of a Life Cycle Assessment is a considerable challenge, given the complexity of the method.

Our view

Procter & Gamble has been a consistent supporter of using Life Cycle Assessment as a tool for assessing and managing environmental issues. We have used it to evaluate many of our products, including laundry detergents, surface cleaners, shampoos, diapers, paper tissues and towels, paper pulp, surfactants (detergent cleansers), and various types of packaging (see for example, De Smet et al, 1996; Saouter, et al, 2002; Science in the Box). Our R&D organizations are also using Life Cycle Assessment as a tool in our product development process. Finally, we have used Life Cycle Assessmen to help municipal governments assess solid waste management options (McDougall, et al, 2001).

Based on these broad experiences, P&G believes that Life Cycle Assessment can be a very valuable tool, especially to improve products or assess the tradeoffs between different choices. However, Life Cycle Assessment has several limitations:

	It is not a substitute for safety or risk assessment, since it cannot produce specific data that relates directly to human or ecological exposure, or toxicity (Owens, 1997a).
	Life Cycle data can be incomplete, and assumptions (for example, about boundaries) can be unclear. This makes it difficult to compare products, especially using results from different studies. Furthermore, in comparing products, Life Cycle Assessment will typically identify trade-offs, not overall "winners and losers."
	There are often uncertainties about the reliability of results, or a lack of understanding about the sensitivity of different lifecycle stages to change.
	Life Cycle Assessment does not provide a direct measure of impacts on the environment due to the aggregation of emissions across different phases of a product's lifecycle. Instead it provides, at best, a measure of potential impacts (Owens, 1997b).

Given these limitations, P&G believes that all users of Life Cycle Assessment, especially for public purposes (e.g., to support environmental claims in the marketplace, or policy making), should follow similar principles:

	Life Cycle Assessment should be used as a decision support tool and not as a decision making tool.
	Methods should be based on the ISO 14040 standards. These procedures are internationally recognized, and agreed by numerous experts in the field.
	Analyses should be publicly available and fully transparent, including the underlying assumptions, data sources, results, and conclusions.
	Life Cycle Assessments should be peer reviewed (as recommended by ISO) and undergo a thorough sensitivity analysis.
	There should be a thorough discussion whether identified differences between products or activities are really meaningful, relative to other human activities.
	In situations where Life Cycle Assessment is to be used for setting public policy, all stakeholders (including industry) should be involved in the design, execution, and interpretation of lifecycle studies.

Like any environmental management tool, Life Cycle Assessment can be very powerful. However, the method can also be easily misused, especially given its inherent complexity. Therefore, it should continue to be used cautiously.

References and Further Readings

De Smut, B., P.R. White, J.W. Owens, 1996. Integrating Life Cycle Assessment Within an Overall Framework for Environmental Management. In Curran, M.A. (ed), Environmental Life Cycle Assessment, McGraw-Hill Companies, New York.

EUROPEN (The European Organization for Packaging and the Environment, Brussels): Use of Life Cycle Assessment in Policy Making in the Context of Directive 94/62/EC, workshop co-organized with the European Commission, Brussels, 20 June 2002, 2001. IPCC Third Report: Climate Change 2001, Synthesis Report.

International Standards Organization Catalogue:

	ISO 14040 (1997). Environmental Management - Life Cycle Assessment - Principles and Framework. ISO/FDIS/TC207SC514040/1997(E).
	ISO 14041 (1998). Environmental Management - Life Cycle Assessment - Goal and Scope Definition and Inventory Analysis.
	ISO 14042 (2000). Environmental Management - Life Cycle Assessment - Life Cycle Impact Assessment.
	ISO 14043 (2000). Environmental Management - Life Cycle Assessment - Life Cycle Interpretation.

McDougall, F., P. White, M. Franke, and P. Hindle, 2001. Integrated Solid Waste Management: A Life Cycle Inventory. Blackwell Science Press, Oxford.

Owens, J.W., 1997a. Life-cycle Assessment in Relation to Risk Assessment: An Evolving Perspective. Risk Analysis, 17(3):359-365.

Owens, J.W., 1997b. Life Cycle Assessment - Constraints in Moving from Inventory to Impact Assessment Journal of Industrial Ecology, 5(2):37-49.

Saouter, E., G. Van Hoof, T.C.J. Feijtel, J.W. Owens, 2002. The Effects of Compact Formulations on the Environmental Profile of North European Granular Laundry Detergents. Part I: Life Cycle Assessment. International Journal Of Life Cycle Assessment. 7:27-38.

Society of Environmental Toxicology and Chemistry (SETAC) Selected Life Cycle Publications

	SETAC, 2003: Life Cycle Assessment and SETAC: 1991 to 1999.
	SETAC, 2002. Life Cycle Impact Assessment: Striving Towards Best Practice.
	SETAC, 1997. Public Policy Applications of Life Cycle Assessment.
	SETAC, 1993. Guidelines for Life Cycle Assessment: A Code of Practice.
	SETAC, 1991. A Technical Framework for Life Cycle Assessment.

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