From Cradle to Grave: Measuring Products' Environmental Impact

Article excerpt

Does the convenience of plastic containers, polystyrene packaging, disposable diapers, and other late-20th-century advancements outweigh the pollution they cause and their nonbiodegradability?

A few years ago, the nation was convulsed by campaigns against disposable products. Shoppers brought their own reusable bags to the supermarket. Churches served coffee in ceramic cups rather than Styrofoam. Parents insisted on cloth diapers. Disposable products were condemned for depleting valuable natural resources and for consuming landfill space. Then life cycle assessment (LCA) entered the fray.

Life cycle assessment attempts to measure the total environmental effects of a product "from cradle to grave." For example, a life cycle analysis by Franklin Associates found that, contrary to all the claims, disposable diapers fare rather well environmentally. While disposables generate four times as much solid waste as reusables, they utilize about half the energy and one-fourth as much water and cause half the air pollution.

Similar studies emerged comparing such things as paper and plastic bags and cups. The disposables weren't so bad after all. Life cycle analysis exploded some myths and simplistic notions. However, the introduction of LCA also spawned some unrealistic expectations.

Today, some proponents of life cycle assessment advocate its use as a tool of environmental policy akin to cost-benefit analysis or risk assessment. James Bridges and Mary Ann Curran, researchers at the Environmental Protection Agency (EPA), claim that "LCA will provide the information to discuss trade-offs and build cooperation throughout the life of every product `from cradle to grave.'" Nick Rowcliffe of Environmental Data Services predicted in 1991 that LCA would "become the most influential environmental management tool of the 1990s."

Life cycle analysis was devised for companies to determine the environmental impact of their products and manufacturing processes. As such, it has a valuable place, but for LCA to be useful for public policy or "social accounting" (as a 1993 article in Environmental Science and Technology put it), practitioners must obtain and synthesize data from a wide range of sources and then translate them into environmental impacts.

As Federal regulation has tightened, companies have come under growing pressure to minimize emissions of waste into air and water. They often want to know whether their raw materials might become scarce or be environmentally harmful. Life cycle assessments can provide answers, because the firms' date are reliable and their goals are usually clear.

The first such assessment was created by Harry Teasley, Jr., at the Coca-Cola Co. around 1970. Coke was deciding between internal production and external sourcing for its glass bottles. The company also was considering replacing its returnable bottles with disposable cans and was examining a new plastic bottle for its soft drinks. Rapidly developing public concern about the environment prompted Coca-Cola to explore the ecological impacts of its packaging choices.

Among other things, the study revealed that, over their life cycle, plastic bottles used less hydrocarbon resources (oil or natural gas derivatives) than did glass bottles. Since plastics are made from hydrocarbons, this result was surprising and gave the company confidence to proceed with the development of today's widely used plastic bottle.

Thus, the first LCAs were conducted for firms using proprietary information to address specific goals. The 3M Co. has used a life cycle perspective to reduce waste and save money. For instance, 3M found that a product coating the company manufactured was getting trapped in the cart holding it. By redesigning the cart, 3M eliminated the places where the solution became trapped. Cleaning the new cart required less solvent and improved the quality of the coated product. …