Implementing the Results of Material Flow Analysis

Abstract

Since the beginning of human development, consumption of resources has increased by many orders of magnitude. This has affected natural processes and structures significantly. The sustainability of this trend is of great concern, and research communities are developing theories, methods, and tools to analyze these developments, to assess their causes, and to contribute to solutions. These include minimizing resource and energy use, and reducing the wastes and emissions that arise from resource use. “An important insight to be drawn from this special issue is that the potential usefulness of the results of MFA depends on establishing the relationship between the societal metabolism on the one hand, and the impacts on policy targets or value areas on the other.” Industrial ecology aims at contributing to this understanding and the solutions that can emerge from it. Several industrial ecology methods have been developed and utilized over the past decades, including material and substance flow analysis, life cycle assessment and environmental input–output analysis as well as their combinations. Each of the methods aims at contributing to solutions to environmental problems from its own specific angle. So far, efforts by the material flow analysis (MFA) and substance flow analysis (SFA) community have been mainly academic. Publications have focused on methodology and model development or on presenting overviews with results of investigations. Although those involved with MFA have always been convinced of the potential usefulness of their efforts, the actual impact they have had on policy making is not so clear. What is the use of knowing how many kilograms of mass enter or leave a country? How does environmental policy benefit from the knowledge that a certain amount of cadmium is being accumulated in society? Did any policy maker ever actually use the results of an MFA study? In short, what exactly is the power of MFA to support policy and management decision making? This question is taken up in this special issue of the Journal of Industrial Ecology, a journal that has served as a platform for presentation and discussion of many MFA studies. Articles with a focus on the utility of the MFA results were invited, rather than articles that focused on the results themselves or any methodological or modeling issues behind those results. This issue includes articles about the ways in which MFA results were or could be implemented and what have been or could be the actual gains of utilizing an MFA approach. We believe this issue identifies the challenges to crossing the bridge between analysis and application, thus achieving more sustainable resource and material use. Support for this issue was provided by the U.S National Science Foundation and the U.S. Environmental Protection Agency. Those agencies had no role in the editorial content or direction of the special issue nor do the contributions to this issue necessarily reflect their views, and, of course, those agencies bear no responsibility for the positions and findings presented here. Instead, the support was provided to stimulate discussion of the application of MFA. In several instances, EPA staff contributed articles to the issue as individual authors rather than representatives of a financing institution of the issue. These contributors represented cases where the editors felt that their perspectives on the utility of MFA would contribute to the topic at hand. The call for papers resulted in more articles of publishable quality than can fit in a single issue. As a result, the articles have been divided between this issue (volume 13, number 5) and the one that follows (volume 13, number 6). We summarize the articles published in both issues in this editorial. The basic principle of MFA and SFA, the law of conservation of mass, is an old one (Brunner & Rechberger 2003). Leontief (1936) pioneered the application of this principle in the field of economics. He used input–output analysis (IOA) to elucidate economic problems of a national scale. The input–output tables on which the IOA are based were later connected with coefficients of environmental pollution to determine the environmental impact of changes in the economic system (Duchin & Steenge 1999). Material balances have been used to study the metabolism2 of cities, specifically the way cities mobilize, “use” and discard materials, since the 1960s (Wolman 1965). Since then, in developed countries, MFA has been used to understand systems, such as densely populated regions (e.g., Brunner & Baccini 1992) and industries (e.g., Ayres & Ayres 1978). In the 1990s, MFA branched into two main activities: material flow accounting, also known as economy-wide MFA, which focuses on providing a picture of a society's overall material metabolism based on statistical data, and material or substance flow analysis, focusing on flows of individual materials or chemicals in, out, and through all kinds of systems (Bringezu et al. 1997). Material flow accounting has become an established activity. Accounts exist, in time series, for many countries in the world. A methodological guide exists, published by the European Union's statistical agency, linking the MFA accounts with official statistics. The idea behind material flow accounting is to represent the economic system in physical rather than monetary terms. Enough data are available at this time to show changes in the overall material metabolism due to economic development. Of growing interest are global trade flows, showing a difference in the material basis of consuming and producing countries. Substance flow analysis focuses on individual substances and is often motivated from concern related to a specific pollutant or, in some cases, resource scarcity. Heavy metals and nutrients are among the most researched substances. SFA has been applied to trace pollutants through watersheds and urban regions (e.g., Stigliani et al. 1993; Lohm et al. 1994) and to describe the metabolism of specific chemicals at the national and international level (e.g., Kleijn et al. 1997; Van der Voet et al. 2000; Spatari et al. 2002). These studies were accounting efforts or relied on static models, based on matrix equations similar to those that are the basis of IOA. Simulating or modeling the dynamic behavior of material or substance flows in human-environment systems allows for forecasting and is therefore most useful in a context of explorations of the future or of scenario analysis (Baccini & Bader 1996). These approaches have been applied in diverse fields. Applications relate to the use of various types of resources (others focus more on the generation of waste and emissions due to delaying mechanisms [e.g., Elshkaki 2007]). The potential usefulness of these methods and models has been identified, by the researchers themselves, in the following areas: to improve the regional or corporate management of materials, so as to optimize resource exploitation, consumption and environmental protection within the constraints of the region or company; to set up monitoring programs to evaluate the effects of policy measures; as a tool for the early recognition of the impact of different scenarios of socio-economic development; and to identify potential future problems related to scarcity as well as waste and emissions. Whether MFA results are implemented in decision making depends on a number of factors. When MFAs are conducted under the auspices of a particular manufacturing entity or industry group, the implementation may be quite straightforward and process adaptation may occur quickly (e.g., Kytzia et al. 1996). This is also the case to some extent in industrial networks. Practical as they are, industrial applications are infrequently published in scientific journals; more typically they are used in proprietary settings. This collection contains two applications at the sectoral level, both coincidentally related to aluminum (Bertram et al. 2009; Cheah et al. 2009). In government decision making at regional, national, and international levels, implementation of MFA results becomes much more difficult. This is because (i) the number of stakeholders involved increases with increasing levels of aggregation and it becomes unclear who is responsible for taking action; (ii) the uncertainty of the data increases; and (iii) there is a need to improve the structure for interpreting MFA results, that is, the goals of material management are not always clearly defined (Allen 2005; Binder 2007). Another significant barrier is that at these levels, governing bodies are not necessarily attuned to their information needs and do not have an appreciation for the potential helpfulness of MFA results. Results from even the most ideally conducted MFA would not be used in such a case. At this point in time, where MFA results have been translated into policies, it has been mainly on the regional scale, in areas with the most forward-thinking governing bodies. As information about the success of these early applications is disseminated, we can expect more demand for these types of analyses. One aspect that is often neglected and is essential for the implementation of the results is consideration of the type of knowledge generated and transmitted to the relevant stakeholders. For example, SFAs that map and estimate emissions from diffuse sources of pollutants have the potential to be useful for policy-making efforts by local government (see, for example, the articles by Månsson and colleagues [2009] and Boehme and colleagues [2009] in this issue, described more below). In most MFA and SFA efforts, system knowledge and understanding is generated—how are resources or pollutants flowing through society and the environment—but with little to no reference to goals (i.e., what would be sustainable?). When policy goals are clear, MFA could be instrumental in identifying potential options for change. By itself, however, it offers no information on how to implement such changes. Transformational knowledge—a translation from policy options into actual policy measures—is required in addition. Thus, additional information to fruitfully use MFA results is needed in two respects: the formulation of policy goals and targets and the formulation of strategies for achieving those goals (Brunner 2002). To what extent MFA has found its rightful place in materials- and substance-related policies is a question explored in this special issue. We are optimistic that this issue of the Journal of Industrial Ecology will increase understanding of where the use of MFA results is headed and what the challenges to implementation are. Although we were hoping to get more articles that described the actual changes in society or policy that have been made as a result of particular implementations of MFA, we are delighted that every article helps illuminate the nexus between the practice of MFA and the potential for application. We have received a wide variety of articles, showing that MFA has found applications in many corners of society, providing support for policies of many different types. The next step would be translating the findings and insights from the MFAs into actual policies and then evaluating the results in society. To what extent this in fact already has happened cannot be concluded from this selection of articles. The examples presented in the special issue show that an improved system understanding has been gained by performing MFA or SFA. Most of them also pinpoint the ways in which the system analyzed could be improved. Some authors went on to evaluate the applicability of their results, acknowledging that a clear conception of which goal should be reached and how, as well as transformational knowledge, was missing from their analysis. An important insight to be drawn from this special issue is that the potential usefulness of the results of MFA depends on establishing the relationship between the societal metabolism on the one hand, and the impacts on policy targets or value areas on the other. If this is not done, the risk for such studies to remain abstract and therefore lack relevancy is large. Establishing this relationship requires linkage with other environmental sciences including those that characterize environmental fate and transport and the potency of effect in the environment of wastes and emissions, or resource scarcity issues. MFA practitioners are probably more attuned to this concept than the entities they seek to serve, and it is important that they show that the power of their results depends on teaming with other disciplines. Articles in this issue range across different areas of application: general metabolic analyses, pollution-oriented applications, resource scarcity-oriented investigations, and a rather large number of waste-related studies. An important article in this issue by Månsson and colleagues (2009) describes the results of an effort to determine not only the practical utility of SFAs, but the factors that influence an SFA's potential to aid in making environmental management decisions. These researchers show that the results of SFAs of diffuse pollutants have been incorporated in several of Stockholm, Sweden's environmental objectives, and that these studies have a strong influence on local policy. Another contribution focusing on pollutants is the article by Boehme and colleagues, representing the decade-long work on the presence of heavy metals in the New York harbor area, their origins in society and potential policies to reduce them. The present article describes the political process that facilitated the use of MFA findings in policy, providing insights very relevant from an implementation point of view. Articles by Matsubae-Yokoyama and colleagues (2009), Cheah and colleagues (2009), and Chancerel and colleagues (2009) take a resource point of view. In their articles, MFA is used as a way to identify new by-product resources or to turn waste into a resource. Matsubae-Yokoyama and colleagues focus on phosphorus. This resource, crucial for agriculture, is nonrenewable, and in the longer run, we may face serious scarcity problems. The authors identify the steel sector as a potential source: steel slag contains significant quantities of phosphorus. Cheah and colleagues examine the impact of expanded use of aluminum in the car fleet on energy resources. The use of aluminum instead of steel reduces energy consumption in the use phase. That is, it increases fuel efficiency by reducing the weight of the car. This is countered by the larger energy use in the production phase. They present a sophisticated examination of how time-related factors—such as how fast the fleet turns over—affect the energy implications of the growing use of aluminum. Chancerel and colleagues (2009) describe the flows of precious metals in electronic waste and the potential of this waste to become a source of secondary materials. They use MFA to pinpoint how recycling practices such as the order of the steps in processing discarded computers shape the opportunities to recover precious metals. A large number of articles deal with waste in one way or another. This apparently has become one of the prime applications: to use MFA to identify waste streams. Nakamura and colleagues (2009) cleverly use a combined input–output and material flow approach to identify, economy-wide, flows of waste polyvinyl chloride (PVC), a material that is the focus of ongoing environmental debate. Mastellone and colleagues (2009) put MFA to very good use to identify a great number of specific waste streams and their potential management in an Italian region, where waste management had become a real problem. Eckelman and Chertow (2009) use MFA to take a comprehensive view of the sources and potential uses of waste in Hawaii, an island where both local resources and disposal capacity are constrained. Arto (2009) combines material flow accounting with the identification of a very specific waste stream—tin wrappers on wine bottles–of importance in Basque country, thereby establishing an interesting link between the two main branches of MFA as described above. The articles taking an economy-wide metabolic approach will be published in the next issue. In some cases, these articles are less directly policy-oriented, but they show a development from pure accounting toward analysis, thereby increasing the policy supporting potential. Wood and colleagues (2009) highlight the drivers of material intensity over time in Australia, which is a first step in finding options to reduce it. Also for Australia, Schandl and colleagues (2009) identify options for dematerialization based on time series of material flow accounts. Muñoz and colleagues (2009) identify international trade flows and their development over time, thus characterising not only the metabolism of national economies but also the distribution pattern throughout the globe. Barles (2009) conducts a multilevel approach by studying the material flows of Paris: Central Paris and suburbs as well as the departmental level. The insights highlight the necessity of performing multilevel analyses for improving strategies to manage resource and waste flows within regions. A variety of environmental leaders contributed thought-provoking columns for this issue. One column (Bertram et al. 2009) describes how MFAs have been used in the aluminum industry, from a tool for facilitating outreach to regulators to internal corporate strategic decision-making. Another column (Aucott 2009) explores the use of MFA to assess the potential releases of mercury from compact fluorescent bulbs. An introduction to the use of data from the U.S. Geological Survey (Sibley 2009), a statistical source of worldwide importance, in MFAs is presented in another column. Finally, three columns explore the use of MFA in policy-making from three very different viewpoints: one author urges readers to recognize the window of opportunity that MFA has for playing an increasing role in U.S. policy issues (Bauer 2009), another talks about the role of MFA in priority setting for sustainable materials management (Allen et al. 2009), and a third (Hashimoto 2009) explores Japan's use of MFAs in its efforts to achieve a Sound Material-Cycle (or Junkan-Gata) Society. This issue's readers may appreciate the guidance provided by reviewers of four recently published volumes aligned with applications of MFA: Biogeochemical Cycles in Globalization and Sustainable Development by Vladimir F. Krapivin and Costas A. Varotsos, Environmental and Material Flow Cost Accounting: Principles and Procedures, edited by Christine Jasch, Handbook of Input-Output Economics in Industrial Ecology, edited by Sangwon Suh, and Waste Input-Output Analysis: Concepts and Application to Industrial Ecology by Shinichiro Nakamura and Yasushi Kondo. In all, we may conclude that the field of MFA is very much alive. MFA has found its way into practical applications of many different types. Through the collection of articles in this special issue it can be concluded that MFA has proven that it can deliver useful information for issues related to resource scarcity, pollution abatement, and waste management. However, there is still a long road to travel before the full potential of MFA as a policy-supporting tool is realized. This may be a matter of time—MFA as a tool is a relatively recent development. It may also be a matter of defining the appropriate moment in the policy cycle to conduct MFAs and the appropriate place within the wide scope of other policy supporting tools. We are, in view of the articles published here, optimistic that MFA will continue to develop and will increasingly find its way into decision-making. Ester van der Voet is an industrial ecologist at the Institute of Environmental Sciences (CML) at Leiden University in Leiden, the Netherlands. Claudia Binder is a faculty member at the Institute of System Science, Innovation and Sustainability Research, University of Graz, in Graz, Austria. Kirsten Rosselot is the owner of Process Profiles, a consulting firm based in Calabasas, California, USA, that specializes in strategic environmental planning and management tools.