Box 12A Life-cycle analysis

Life-cycle analysis (LCA) is a technique which allows the environmental implications of various products to be assessed. The impact of products and services is the sum of the resources required plus the amount of emissions and waste. The material and energy intensity determines the level of efficiency of the process employed to deliver a given product or service. LCAs are inventories of the materials and energy requirements as well as of the waste released at each stage of a product's life. The methodology of compiling these inventories is a powerful tool to assist companies to improve products and reduce energy and material consumption in production processes. It can also assist governments to formulate product policies and implement ecolabelling schemes. Dissemination of this information can guide consumers towards more environmentally responsive choices.

Several studies have been developed in various European countries attempting to assess the impact of products. Major difficulties in compiling environmental inventories have been encountered because of the detailed information required. More difficulties emerge in the assessment of the results of LCAs. In some cases different approaches and assumptions have led to contradictory conclusions when trying to compare different products on the basis of their overall environmental impacts. Among other examples are the controversial conclusions of three studies on packaging alternatives for milk. Because of different approaches and categories of emissions considered, the results of the studies were considerably divergent. A Swedish study concluded that milk cartons were preferable to refillable glass, while a Swiss study found in favour of refillable glass. In a German study the milk carton and the glass bottle were found to be equally acceptable: the milk carton ranked best as regards atmospheric emissions, while the glass bottle ranked best considering emissions into water.

Contradictory conclusions of product LCAs can be explained by differences in the definition of processes and data inventory, which affect the whole accounting procedure. Notwithstanding, these studies have shown that the number of times a beverage package is re-used, and the transportation involved, as well as technology, play a major role. While LCA provides a tool to improve product design and manufacturing processes, comparing products on this basis alone could be misleading until standardised LCA methods are established.