ANALYSIS: Life-Cycle Assessment

Dispatch from SSC Intern Julie Holst

It is becoming more and more obvious to consumers that there are numerous threats to consider when purchasing a product. Every stage of that product’s life, (extraction of raw materials, primary manufacturing, secondary manufacturing/assembly, packaging, transport/distribution, installation/use/maintenance, and end of life management scenarios) can have various threats to the environment and to human health. The most thorough way to comprehend such affects is to understand an existing, or create a new, life cycle assessment (LCA).

LCA is a process used to analyze the economic and environmental tradeoffs of a product or technology (UNEP, 2004). As the name suggests, the environmental impact of a product or technology is tracked along its entire life cycle, ranging from raw material production to EoL disposal in what is called a cradle-to-grave approach (US EPA, 2006). Typically, a comprehensive LCA would account for all inputs of raw material and energy required for the duration of a product's lifespan from manufacture, use and maintenance phase, to EoL (US EPA, 2006). Depending on the type and volume of input required, outputs to the environment, such as carbon dioxide, are tracked throughout the life cycle.

The process of LCA was developed during the 1960s, when concerns about natural resource scarcity first became prominent (US EPA, 2006). The Coca-Cola Company was the first major firm to conduct a voluntary analysis, and this became the basis for current LCA projects in the United States. Using a process similar to the modern LCA in 1969, the company determined that plastic bottles were less harmful to the environment than glass, due to the weight difference and its effect on transportation efficiency (ecomii.com, 2009). Interest in LCAs waned in the next decades until the issue of solid waste became prominent in 1988 (US EPA, 2006). Concerns over methodological inconsistencies were voiced by manufacturers, and the International Standardization Organization (ISO) developed a standardization of LCAs in 1997. The ISO 14040 and ISO 14044 have been revised many times since their inception, and are now in the 2006 edition.

According to the United States Environmental Protection Agency (USEPA), a comprehensive LCA consists of four stages: goal definition and scoping, inventory analysis, impact assessment, and interpretation (2006). In the goal definition and scoping phase, the type and accuracy of information and method needed for meaningful interpretation are determined. During the second phase, the inventory phase, all the necessary input data are collected. In the impact assessment, the data are evaluated as for their impact on the environment and human health. Finally, the interpretation phase is the conclusion and recommendation stage of LCA.