How Eco-Friendly is that “GREEN PRODUCT,” really?

by Cary Miller

More and more products claim to be “green” or “environmentally-friendly.” Can we really measure how green a product is? Can we see how its environmental impacts compare to other products on the market, green or otherwise? We can, and Life Cycle Assessment is one way to accomplish this. A Life Cycle Assessment, or LCA, provides a way to see and realize environmental burdens associated with a material throughout its entire life cycle -- manufacturing, use, maintenance and disposal or recycling. One of the basic purposes of this process is to eliminate the masking of environmental impacts by shifting them to another medium (land, air, or water) or to a different life cycle stage.

Some of the concepts behind Life Cycle Assessment have been around since the early 1970s, and were created consequentially during the search for energy-efficient manufacturing methods. Research was conducted worldwide, and by the 1990s, a standard methodology had been put forward by the U.S. Environmental Protection Agency (EPA) and the Society of Environmental Toxicology and Chemistry (SETAC). This widely used model has four components: goal and scope definition; life cycle inventory (LCI); life cycle impact assessment (LCIA); and improvement analysis.

The first step, Goal and Scope Definition, involves stating the purpose of the study and the boundaries. When looked at from an ecological perspective, everything is essentially “connected” somehow. For this reason, it is essential to explicitly state where the limits are being drawn. The purpose of the study is important for interpreting the collected information and impacts, and is usually the driving force in looking for improvements in the life cycle.

Next, a Life Cycle Inventory is conducted. All stages of the life cycle are identified, from the collection of raw materials through to the eventual disposal or reuse. This is often referred to as cradle-to-grave, or, in the case of recycled materials, cradle-to-cradle. Once these stages are identified, the energy use, raw materials and environmental pollutants at each life cycle stage are measured and accounted for.

The Life Cycle Impact Assessment stage takes the data from this inventory and examines how these inputs and outputs affect both human and environmental health. This could include everything from increases in respiratory illness to loss of watershed. One of the problems with LCIAs is a lack of common impact assessment methods. In the absence of widely accepted standards, it may be best if the methods are clearly defined for each particular study based on the particular goals and scope.

Finally, the Improvement Analysis helps evaluate opportunities to reduce energy and material inputs, as well as environmental impacts. The goals of the study guide the improvements. Possible improvements are often examined through trade-off analysis, or looking at shifting impacts from different stages in the life cycle or between environmental areas. These trade-offs can be compared to each other in order to determine the improvements with least impact. These improvements often mean savings in money and efficiency, as well as reducing negative environmental impact.

In order for the U.S. government to utilize LCA analyses in making environmentally responsible purchasing decisions, the National Institute of Standards and Technology (NIST) has developed software that compares products both environmentally and economically. The Building for Environmental and Economic Sustainability (BEES) software includes actual environmental and economic performance data for nearly 200 building products, and provides scores for impacts such as global warming and human health, as well as first and future financial costs. The software also allows the user to assign levels of importance to the costs and impacts depending on a user’s specific priorities.

What more and more researchers now realize is that Life Cycle Assessments may be better suited for educational purposes rather than actual comparisons. The sheer scope, depth and uniqueness of many LCAs render them somewhat ineffective for direct side-by-side comparisons of products or materials. Until standards for comparison are developed and accepted, assessments are most valuable as a means of understanding the processes and impacts that are involved with a particular product. The better we understand the impacts of each product, as it travels from cradle to grave, the better we are able to judge how truly “green” it is, and how well it will help us reach a sustainable future.

Websites for more info:

• Carnegie Mellon University Green Design Initiative www.eiolca.net

• Life Cycle Assessment Links www.life-cycle.org

• U.S. EPA Life-Cycle Assessment www.epa.gov/ORD/NRMRL/lcaccess/

• BEES 3.0 www.bfrl.nist.gov/oae/software/bees.html