Part III Other types of audit
B. Mattsson and P. Olsson, The Swedish Institute for Food and
10.6 Introduction to LCA
The first European LCA studies of food products were performed at the beginning of the 1990s. Universities, institutes and companies have participated in the development of LCA methodology and the application of LCA to different types of products. SETAC, the Society of Toxicology and Chemistry, has played an important role in the development of LCA methodology and now LCA has become a part of the environmental management system ISO 14000. The ISO certification is very important for the credibility of LCA and for the future use of LCA in companies.
LCA has primarily been used for product development. In the food area studies have often been restricted to the packaging system but studies of complete product systems are becoming more common. The environmental information gained in an LCA is of course only part of the information needed by the decision makers in product development. However, it is increasingly important to be able to show an awareness of environmental issues towards
consumers, investors, etc. There is also a clear potential for cost savings when the use of energy, water and other resources can be reduced.
10.6.1 LCA working procedure
LCA is a method used to investigate and assess the environmental impact of a material, product or service throughout its entire life cycle from raw material acquisition through production, use and disposal (see Fig. 10.2). The product system studied is delimited from the surrounding environment by a system boun-dary. The energy and material flows crossing the boundary are accounted for as:
1. resources used for production, transportation, etc. (inputs), and
2. emissions and waste leaving the product system and entering the surrounding environment (outputs).
The parameters are often numerous, which can make interpretation difficult.
Hence, emissions contributing to the same environmental impact (impact category) are aggregated to facilitate interpretation of the results.
The procedure for making an LCA consists of four phases (Fig. 10.3). In the first phase, the goal and scope definition, the purpose of the study and its range are defined. In the goal and scope definition important decisions are made concerning boundary setting and definition of the functional unit (i.e. the reference unit). During the inventory analysis, information about the product system is gathered and relevant inputs and outputs are quantified. In the impact assessment, the data and information from the inventory analysis are linked with specific environmental impacts so the significance of these potential impacts can be evaluated. Finally, in the interpretation phase, the findings of the inventory analysis and the impact assessment are combined and interpreted to meet the previously defined goals of the study. Formalised, quantitative weighting methods are available for the aggregation of either inputs and outputs or environmental effects into one index. These methods originate from the social sciences, since the values concerned are held by people within the social system.
A review of weighting in LCA has been published by Bengtsson (2000).
10.6.2 System boundaries
The choice of system boundaries has been discussed by Tillman et al. (1994).
Ideally, the system boundary should be between the technological system and nature. In agricultural production it is difficult to make this delimitation since production takes place in nature. For example, it has been discussed whether the soil should be regarded as part of the technological system or not. Delimitation in time and of the geographical area must also be made, and boundaries established between manufacturing of the product studied and the production of capital goods. In LCA calculations, the industrial production of capital goods, such as machinery and buildings, is normally left out. The reason is that the capital goods often have a long lifetime, which means that the environmental
burdens of their production would be divided among a large quantity of products: for just one product, the result is likely to be negligible.
10.6.3 The functional unit
The definition of the functional unit is determined by the specified main function of the product system under study. The functional unit should be a relevant, well defined and strict measure of the service that the system delivers;
it is the basis for the analysis. All data is related to the functional unit (Lindfors et al., 1995).
In most LCA studies of food products, the mass of a specific product has been defined as the functional unit, e.g. 1 kg of bread from a bakery or 1 kg of apples Fig. 10.2 Principal life cycle steps included in an LCA. The product system studied is delimited from the surrounding environment by a system boundary and the energy and
material flows crossing the boundary are accounted for.
from the greengrocers. As pointed out by Andersson (1998), there are various parameters relevant to the function of a food product: the content of various nutrients and fibres, the calorific value, shelf-life, taste, smell and appearance. A minimum requirement must be that a given food is hygienically and toxicologically safe. The definition of the functional unit must be determined by the goal of the study. Andersson points out also that, when various food products are to be compared, it seems relevant to take into consideration their role or function in the diet, for example the content of proteins for meat or fish.
10.6.4 Allocation
Allocation of environmental burdens may be necessary, for example when the same process yields more than one product, i.e. functions. There are plenty of examples of this type of multifunctional process in agriculture and food processing, for instance dairy cow production yields both milk and meat, vegetable oil crops yield both oil and feed and, when cheese is produced, the process also yields whey.
Allocation procedure in life cycle assessment is a separate field of research that has been addressed by Ekvall (1999). Ekvall gives a thorough overview of allocation methods, of which only a few are addressed here. According to the international standard the following approaches should be used in the following order of preference (ISO 14041:1998).
Fig. 10.3 Procedure and application of LCA studies. (Source: ISO 14040: 1998.)
• Allocation should be avoided, wherever possible, either through division of the multifunction process into sub-processes and collection of separate data for each sub-process, or through expansion of the system investigated until the same functions are delivered by all systems being compared.
• Where allocation cannot be avoided, the allocation should reflect the physical relationships between the environmental burdens and the functions delivered by the system.
• Where such physical, causal relationships alone cannot be used as the basis for allocation, the allocation should reflect other relationships between the environmental burdens and the functions.
For agricultural production it is often difficult to divide the production system into sub-systems, for example wheat and straw from a wheat crop. According to Ekvall (1999), system expansion requires that there be an alternative way of generating the functions and that data can be obtained for this alternative production. This means that system expansion requires the collection and processing of additional data. This extra work is justified only when the system expansion can be expected to yield information that is significant for the conclusions of the LCA. For the accounting type of LCA, e.g. for Environmental Product Declarations, system expansion is probably not an option since the environmental burdens of other products would be involved.
10.6.5 Data collection and data quality
When interpreting the results of an LCA, it is important to have an understanding of the quality and uncertainty of the inventory data. A life cycle study is a summary of a large amount of input data of varying quality. Usually, the uncertainties cannot be quantified; however, they can be expected to be large. The cumulative effects of uncertainties in both inventory and impact assessment are potentially very significant for the overall results. According to Barnthouse et al. (1997), there is a clear need to evaluate the influence these uncertainties have upon final (and intermediate) LCA results. Although this is difficult to achieve, an effort should at least be made to present information about how representative the input data are, for example, and how the uncertainties may have influenced the results. For the case studies, Barnthouse made comparisons with other data sources whenever possible; however, this could not be done for specific production data provided by industry.
10.6.6 The use of LCA
According to the ISO standard, LCA can be useful for various purposes:
• identifying opportunities to improve the environmental aspects of products
• decision making in industrial companies or other organisations, such as strategic planning, setting priorities, or product and process design or re-design
• selecting relevant indicators of environmental performance, and
• marketing, such as environmental claims, eco-labelling schemes, or Environmental Product Declarations.
LCA can be useful in auditing since it provides a complete picture of the environmental impact of a business’s operations. It can, therefore, provide a standard against which to audit and impove current environmental performance.
It also requires a new set of auditing skills in verifying a particular LCA or the incorporation of LCA principles into an existing EMS.