What Is Life Cycle Assessment?

As environmental awareness increases, industries and businesses have started to assess how their activities affect the environment. Society has become concerned about the issues of natural resource depletion and environmental degradation. Many businesses and industries have responded to this awareness by providing “greener” products and using “greener” processes. The environmental performance of products and processes has become a key issue, which is why some companies are investigating ways to minimize their effects on the environment. Many companies have found it advantageous to explore ways of moving beyond compliance using pollution prevention strategies and environmental management systems to improve their environmental performance. One such tool is called life cycle assessment (LCA). LCA was first defined in the way we know it today at the Vermont Conference of the Society of Environmental Toxicology and Chemistry (SETAC 1991). The concept is holistic, cradle‐to‐grave environmental approach which provides a comprehensive view of the environmental aspects of a process or product throughout its life cycle by promoting analysis, quantification, and understanding of all the environmental impacts associated with an activity. But more importantly LCA identifies the potential transfer of environmental impacts from one media to another and/or from one life cycle stage to another. If an LCA were not performed, these trade‐offs might not be recognized and properly included in the analysis because it is outside of the typical scope or focus of the decision‐making process. The provision of such information aids in decision making and helps in the formulation of environmental strategy and policy as such, and LCA has been accepted into the mainstream of environmental thought and management (Azapagic 2000; Cooper 2003; Curran 2003, 2012, 2015; Das 2002, 2005; ENDS 1996; Pineda et al. 2002; SETAC 1991, 1993; UNEP‐SETAC 2000, 2011; USEPA 2006).

The LCA process is a systematic, phased approach. Its components, discussed in details in Section 6.5.3.2, can be listed briefly as follows:

1. Goal definition and scoping – Define and describe the product, process, or activity. Establish the context in which the assessment is to be made and identify the boundaries and environmental effects to be reviewed for the assessment.
2. Inventory analysis – Identify and quantify energy, water and materials usage, and environmental releases (e.g. air emissions, solid waste disposal, wastewater discharge).
3. Impact assessment – Assess the human and ecological effects of energy, water, and material usage and the environmental releases identified in the inventory analysis.
4. Interpretation – Evaluate the results of the inventory analysis and impact assessment in terms of the goal established at the outset. This makes it possible to select the preferred product, process, or service with a clear understanding of the uncertainty and the assumptions used to generate the results.

Benefits of Conducting an LCA

An LCA will help decision‐makers select the product or process that results in the least impact to the environment. This information can be used with other factors, such as cost and performance data to select a product or process. LCA data identify the transfer of environmental impacts from one media to another (e.g. eliminating air emissions by creating a wastewater effluent instead) and/or from one life cycle stage to another (e.g. from use and reuse of the product to the raw material acquisition phase). Without an LCA, the transfer might be overlooked and excluded from the analysis because it is outside the typical scope or focus of product selection processes.

For example, when selecting between two rival products, it may appear that Option 1 is better for the environment because it generates less solid waste than Option 2. However, LCA might indicate that the first option actually creates larger cradle‐to‐grave environmental impacts when measured across air, water, and land. Perhaps, for example, it is seen to cause more chemical emissions during the manufacturing stage. Therefore, the second product although it produces solid waste may actually produce less cradle‐to‐grave environmental harm or impact than the first technology because its chemical emissions are lower.

This ability to track and document shifts in environmental impacts can help decision‐makers and managers fully characterize the environmental trade‐offs associated with product or process alternatives.

By performing an LCA, researchers can

1. develop a systematic evaluation of the environmental consequences associated with a given product
2. analyze the environmental trade‐offs associated with one or more specific products/processes to help gain stakeholder (state, community, etc.) acceptance for a planned action
3. quantify environmental releases to air, water, and land in relation to each life cycle stage and/or major contributing process
4. assist in identifying significant shifts in environmental impacts between life cycle stages and environmental media
5. assess the human and ecological effects of material consumption and environmental releases to the local community, region, and world
6. compare the health and ecological impacts between two or more rival products/processes or identify the impacts of a specific product or process
7. identify impacts to one or more specific environmental areas of concern

Limitations of LCAs as Tools

Performing an LCA can be resource and time intensive. Depending upon how thorough an LCA the users wish to conduct, gathering the data can be problematic and the unavailability of crucial data can greatly impact the accuracy of the final results. Therefore, it is important to weigh the availability of data, the time necessary to conduct the study, and the financial resources required against the projected benefits of the LCA.

LCA will not determine which product or process is the most cost effective or works the best. Nor does it take into account broader issues of acceptability. Therefore, the information developed in an LCA study should be used as one component of a more comprehensive process of assessing the trade‐offs between performance and economic, geopolitical and social costs.