Resource Use in Small Island States

Iceland and Trinidad and Tobago are small open, high‐income island economies with very specific resource‐use patterns. This article presents a material flow analysis (MFA) for the two countries covering a time period of nearly five decades. Both countries have a narrow domestic resource base, their economy being largely based on the exploitation of one or two key resources for export production. In the case of Trinidad and Tobago, the physical economy is dominated by oil and natural gas extraction and petrochemical industries, whereas Iceland's economy for centuries has been based on fisheries. More recently, abundant hydropower and geothermal heat were the basis for the establishment of large export‐oriented metal processing industries, which fully depend on imported raw materials and make use of domestic renewable electricity. Both countries are highly dependent on these natural resources and vulnerable to overexploitation and price developments. We show how the export‐oriented industries lead to high and growing levels of per capita material and energy use and carbon dioxide emissions resulting from large amounts of processing wastes and energy consumption in production processes. The example of small open economies with an industrial production system focused on few, but abundant, key resources and of comparatively low complexity provides interesting insights of how resource endowment paired with availability or absence of infrastructure and specific institutional arrangements drives domestic resource‐use patterns. This also contributes to a better understanding and interpretation of MFA indicators, such as domestic material consumption.     

The Metabolic Transition in Japan

The notion of a (socio‐) metabolic transition has been used to describe fundamental changes in socioeconomic energy and material use during industrialization. During the last century, Japan developed from a largely agrarian economy to one of the world's leading industrial nations. It is one of the few industrial countries that has experienced prolonged dematerialization and recently has adopted a rigorous resource policy. This article investigates changes in Japan's metabolism during industrialization on the basis of a material flow account for the period from 1878 to 2005. It presents annual data for material extraction, trade, and domestic consumption by major material group and explores the relations among population growth, economic development, and material (and energy) use. During the observed period, the size of Japan's metabolism grew by a factor of 40, and the share of mineral and fossil materials in domestic material consumption (DMC) grew to more than 90%. Much of the growth in the Japanese metabolism was based on imported materials and occurred in only 20 years after World War II (WWII), when Japan rapidly built up large stocks of built infrastructure, developed heavy industry, and adopted patterns of mass production and consumption. The surge in material use came to an abrupt halt with the first oil crisis, however. Material use stabilized, and the economy eventually began to dematerialize. Although gross domestic product (GDP) grew much faster than material use, improvements in material intensity are a relatively recent phenomenon. Japan emerges as a role model for the metabolic transition but is also exceptional in many ways.     

Materials Flow Accounting in Sweden Material Use for National Consumption and for Export

This article presents Swedish economy‐wide material flow accounts for the period 1987‐1998. It also shows possibilities for enhancing the international comparability of aggregated data on material use, by distinguishing between materials used for consumption and export purposes. The direct material input (DMI) is used as an aggregate measure to estimate the amounts of natural resources (except water and air) that are taken from nature into the economy within a year, including imports to and production within the region in question. The division of materials used for consumption and export purposes avoids double counting trade flows when DMI is applied to a group of countries. The annual DMI in Sweden for 1997‐1998, including production and imports, amounts to 24 to 27 metric tons per capita (t/c). The fossil fuel input varies only slightly over the period, from 3.2 t/c in 1991 to 3.6 t/c in 1996, a level deemed unsustainable by the Swedish Environmental Protection Agency. The input of renewable raw materials varies between 8 and 9 t/c. Ores and minerals vary between 11 and 15 t/c. The DMI puts Sweden above estimates made for Germany, the United States, and Japan and in the same range as the Netherlands. The differences in these values can mainly be explained by the relative importance of exports as compared to the size of the economy and by the variation in system boundaries for the data on natural resources. The system boundaries and data sources for natural resources need to be further defined to make the measures fully comparable. Around 5 t/c is exported, whereas the rest, around 20 t/c, is national consumption. The aggregate direct material consumption (DMC), which is the DMI minus exports, communicates the magnitude of resource use. Comparisons of the input with solid waste statistics indicate that quantity of waste (excluding mining waste) in Sweden is equal to about 10% relative of the total resource use. Material collected for recycling by the waste management system is equal to about 5% of the amount of virgin resources brought into society each year.     

区域生态经济系统的物质输入与输出分析——以常州市武进区为例

运用物质流分析（MFA）方法,对江苏省常州市武进区生态经济系统中物质输入与输出进行了系统的分析,结果表明：（1）随着社会经济发展和人口增长,武进区物质输入总量及人均物质输入量也在增加,但递增速率均远小于GDP增长速率,而物质输出总量及人均物质输出量则呈现递减趋势;（2）在不考虑水的因素情况下,武进区物质输入量保持较快的上升速度,其中固体物质的增长速率远远大于气体物质的增长速率;物质输出量则呈总体下降趋势,其中以气体物质输出量的贡献最大,对环境造成污染的物质以气体特别是以化石燃料燃烧排放的废气和工业废气为主;（3）排除占大部分比例农业用水的上升,工业用水、城镇生活用水和地下水总量及人均利用强度都在减少;同时,总的废水排放量及人均排放量在减少,其中又以生活废水排放量的减少最快,其次是工业废水;（4）单位GDP物质输入量的变化处于波动状态,同期的单位GDP物质输出量则呈递减趋势,单位GDP用水量和单位GDP废水排放量则有相同的递减趋势,表征了武进区资源利用效率的稳步提高,区域经济增长和环境压力也在逐步脱钩。上述结果体现了武进区近年来循环经济发展模式的优势,但还存在较多问题,说明武进区在调整物质利用强度和提高资源利用效率方面还需下更大的功夫,并采取相关措施,以期提高实施循环经济战略与建设节约型社会的地位和意义。文章最后结合研究区实际情况就区域环境一经济的协调发展进行了展望,指出了物质流分析方法在应用中的一些缺陷,为今后该领域的进一步研究提供了借鉴。     

Accounting for the Material Stock of Nations

National material stock (MS) accounts have been a neglected field of analysis in industrial ecology, possibly because of the difficulty in establishing such accounts. In this research, we propose a novel method to model national MS based on historical material flow data. This enables us to avoid the laborious data work involved with bottom‐up accounts for stocks and to arrive at plausible levels of stock accumulation for nations. We apply the method for the United States and Japan to establish a proof of concept for two very different cases of industrial development. Looking at a period of 75 years (1930–2005), we find that per capita MS has been much higher in the United States for the entire period, but that Japan has experienced much higher growth rates throughout, in line with Japan's late industrial development. By 2005, however, both Japan and the United States arrive at a very similar level of national MS of 310 to 375 tonnes per capita, respectively. This research provides new insight into the relationship between MS and flows in national economies and enables us to extend the debate about material efficiency from a narrow perspective of throughput to a broader perspective of stocks.     

Material flow analysis (MFA) of an eco-economic system: a case study of Wujin District, Changzhou, China

The economic and ecological aspects of a social system are coherently linked and can be examined by its material and energy flows. In this study, we used the material flow analysis (MFA) to model the material input and output of the Wujin District of Changzhou City, Jiangsu Province in China. It was revealed that: (1) total material input and material input per capita increased with economic development, while the total material output and material output per capita decreased consistently; (2) except for water, the total material input continued to increase. Input of solid materials grew faster than that of gaseous materials, while the total material output declined. The gas output accounted for the largest proportion of the output resulting in primary environmental pollution as burned fossil fuel; (3) water use in agriculture continued with an increasing trend while that in industrial and residential sectors decreased per capita. The total wastewater discharge and wastewater discharge per capita decreased with a faster decreasing rate of residential wastewater discharge followed by industrial wastewater discharge; (4) material input per unit GDP fluctuated and material output per unit GDP decreased. A decreasing trend in both water use and wastewater discharge per unit GDP was disclosed. These results suggest that the efficiency of resource use in the Wujin District has improved. This weakened the direct link between economic development and environmental deterioration. Additionally, we discussed the harmonic development between environment and economy. Potential limitations of MFA’s application were also discussed. It is suggested that effective measures should be taken for the enforcement of circular economic strategies and the construction of a resource-saving economy __________ Translated from Acta Ecologica Sinica, 2006, (8): 2578–2586 [译自:生态学报]     

Material flow analysis (MFA) of an eco-economic system:a case study of Wujin District,Changzhou,China

The economic and ecological aspects of a social system are coherently linked and can be examined by its material and energy flows.In this study,we used the material flow analysis (MFA) to model the material input and output of the Wujin District of Changzhou City,Jiangsu Province in China.It was revealed that:(1) total material input and material input per capita increased with economic development,while the total material out-put and material output per capita decreased consistently;(2) except for water,the total material input continued to increase.Input of solid materials grew faster than that of gaseous materials,while the total material output declined.The gas output accounted for the largest pro-portion of the output resulting in primary environmental pollution as burned fossil fuel; (3) water use in agriculture continued with an increasing trend while that in industrial and residential sectors decreased per capita.The total wastewater discharge and wastewater discharge per capita decreased with a faster decreasing rate of residential was-tewater discharge followed by industrial wastewater dis-charge; (4) material input per unit GDP fluctuated and material output per unit GDP decreased.A decreasing trend in both water use and wastewater discharge per unit GDP was disclosed.These results suggest that the effi-ciency of resource use in the Wujin District has improved.This weakened the direct link between economic develop-ment and environmental deterioration.Additionally,we discussed the harmonic development between environ-ment and economy.Potential limitations of MFA's application were also discussed.It is suggested that effec-tive measures should be taken for the enforcement of cir-cular economic strategies and the construction of a resource-saving economy     

The Energetic Metabolism of the European Union and the United States: Decadal Energy Input Time-Series with an Emphasis on Biomass

This article presents an assessment of energy inputs of the European Union (the 15 countries before the 2004 enlargement, abbreviated EU‐15) for the period 1970–2001 and the United States for 1980–2000. The data are based on an energy flow analysis (EFA) that evaluates socioeconomic energy flows in a way that is conceptually consistent with current materials flow analysis (MFA) methods. EFA allows assessment of the total amount of energy required by a national economy; it yields measures of the size of economic systems in biophysical units. In contrast to conventional energy balances, which only include technically used energy, EFA also accounts for socioeconomic inputs of biomass; that is, it also considers food, feed, wood and other materials of biological origin. The energy flow accounts presented in this article do not include embodied energy. Energy flow analyses are relevant for comparisons across modes of subsistence (e.g., agrarian and industrial society) and also to detect interrelations between energy utilization and land use. In the EU‐15, domestic energy consumption (DEC = apparent consumption = domestic extraction plus import minus export) grew from 60 exajoules per year (1 EJ = 10¹⁸ J) in 1970 to 79 EJ/yr in 2001, thus exceeding its territory's net primary production (NPP, a measure of the energy throughput of ecosystems). In the United States, DEC increased from 102 EJ/yr in 1980 to 125 EJ/yr in 2000 and was thus slightly smaller than its NPP. Taken together, the EU‐15 and the United States accounted for about 38% of global technical energy use, 31% of humanity's energetic metabolism, but only 10% of global terrestrial NPP and 11% of world population in the early 1990s. Per capita DEC of the United States is more than twice that of the EU‐15. Calculated according to EFA methods, energy input in the EU and the United States was between one‐fifth and one‐third above the corresponding value reported in conventional energy balances. The article discusses implications of these results for sustainability, as well as future research needs.     

The Sweetening of the World's Diet

Objective: Using data from many countries in the world combined with in‐depth U.S. dietary data, we explored trends in caloric sweetener intake, the role of urbanization and income changes in explaining these trends, and the contribution of specific foods to these changes. Research Methods and Procedures: Food disappearance data from 103 countries in 1962 and 127 in 2000 were coupled with urbanization and gross national income per capita data in pooled regression analysis to examine associations between these factors and caloric sweetener intake. Three nationally representative surveys from 1977 to 1978, 1989 to 1991, and 1994 to 1996 plus 1998 are used to examine caloric sweetener intake trends in the United States and the foods responsible for these changes. Results: Increased consumption of caloric sweetener is one element in the world's dietary changes, represented by a 74‐kcal/d increase between 1962 and 2000. Urbanization and income growth represent 82% of the change. U.S. data show an 83‐kcal/d increase of caloric sweetener consumed—a 22% increase in the proportion of energy from caloric sweetener. Of this increase, 80% comes from sugared beverages; restaurant and fast food sources are represented in greater proportions. Discussion: Caloric sweetener use has increased considerably around the world. Beverage intake seems to be a major contributor.     

Static material flow analysis of neodymium in China

Neodymium is one of the most important enabling materials for next‐generation clean technologies, especially electric vehicles and wind turbines. As the world's largest producer of rare earth minerals, China dominates the global neodymium supply and a considerable amount of primary neodymium resources are from illegal mining. Many studies have been conducted on the material flow of neodymium in different regions, but few studies focus on China. In this study, a static material flow analysis of neodymium is conducted to quantitatively analyze the industrial chain structure of neodymium in China and to calculate the neodymium output from illegal mining. The results quantitatively depict the neodymium material flow of each stage of China's neodymium industrial chain in 2016, which indicates that 12.3–17.0 kt of primary neodymium resources were from illegal mining. On the basis of the results, reasonable conclusions can be drawn that the recycling of neodymium from end‐of‐life products provides an important opportunity to both reduce illegal rare earth mining and cope with increasing neodymium demand.     

Regional material flow accounts for China: Examining China's natural resource use at the provincial and national level

Over the last three decades, China has experienced the most dynamic economic development lifting living standards and resulting in fast‐growing use of natural resources. In the past, the focus has been on national MFA accounts which do not do justice to the second largest economy, home to 19% of the world population and having 30% of global material use. In this research, we calculate material extraction for China at the regional level during 1995–2015 using the most recent available statistical data and applying the most up‐to‐date international calculation methods. In particular, we combine a bottom‐up and top‐down approach for constructing the dataset of China's economically used Domestic Extraction (DEU) in an integrated way. This approach also improves the Chinese national material flow accounts and allows us to present a reliable database of DE of materials for China to date. Our new dataset provides the basis for calculating material footprints and environmental impacts of China's regions. The dataset enables us to evaluate regional resource efficiency trends in China. We find that during the past two decades, China's material use has grown strongly from 11.7 billion tonnes in 1995 to 35.4 billion tonnes in 2015. Material use has accelerated between 2000 and 2010 but slowed down between 2010 and 2015 reflecting the economic contraction caused by the Global Financial Crisis which reduced the global demand for China's manufacturing and a reorientation of China's economic policy settings toward quality of growth. Unsurprisingly, different regions play different roles in the supply chain of materials, achieving different economic performances resulting in very diverse material efficiency outcomes. This information is important to allow for a targeted policy approach to increase resource efficiency, reduce environmental impacts of resource use, and grow wellbeing in China with large positive implications for global sustainability. This study provides the basis for the development of relevant resource management policies for different regions in the future.     

Streamlined approach for assessing embedded consumption of lithium and cobalt in the United States

In today's complex global supply chains, time and data intensive analyses are required to understand global flows of mineral commodities from mine to consumer, particularly for mineral commodities in products (electronics, automobiles, etc.) that contain multiple parts with many mineral commodities. National and regional analyses require additional time and data to incorporate international trade flows. However, data limitations and time constraints often prohibit global and national material flow analyses for minor metals. Here we present a methodological approach to circumvent these constraints by utilizing readily available industry-level global data from the United Nations Statistics Division and national industrial data to estimate total requirements for a mineral commodity. We apply this approach to lithium and cobalt use in the United States for the year 2018 and distinguish between apparent raw material consumption versus inferred embedded consumption of lithium and cobalt materials in all forms. The results show that more than half of the United States’ total requirements for both lithium and cobalt is in parts and products that were manufactured outside the United States. In large part, this is due to limited US manufacturing capability for lithium-ion battery materials and cells and the United States’ high import reliance for electronics that use those batteries.     

Ship Breaking and the Steel Industry in Bangladesh: A Material Flow Perspective

Bangladesh has emerged as a leading ship breaking nation. We conducted a material flow analysis of steel in Bangladesh with an emphasis on the ship breaking industry (SBI). The total aggregate domestic steel consumption in fiscal year (FY) 2010 was 2,930,000 tonnes (t) in Bangladesh; SBI met approximately 51% of the demand for raw materials and 37% of the demand for finished steel products. Rolling industries output in FY2010 was 1,451,000 t; 23% of the input for this production was from ship breaking sources. Dismantled ships also generate high‐quality reusable steel scraps. SBI was found to be the sole source of scraps for small rerolling industries in Bangladesh, and their output in 2008 more than doubled as compared to 2005. Larger rolling industries fulfilled their input needs for steel scraps by using both SBI and imported materials. We found a sharp increase in input imports during the global ship breaking recession in 2003–2007 and when Bangladesh's SBI faced a temporary ban in 2010. Induction furnaces in Bangladesh in FY2010 produced a total of 787,000 t of billets; more than 40% was from ship‐sourced scraps. In 2008, the country's steel consumption was 3,220,000 t, that is, 22 kilograms per person, and the intensity of steel use was 40 grams per U.S. dollar, which was much higher than that of other developing countries with a similar per capita gross domestic product (GDP). The country exhibited a high level of steel consumption relative to its GDP, which is indicative of the contribution of SBI.     

Anthropogenic Carbon Stock Dynamics of Pulp and Paper Products in Germany

Carbon‐based materials (CBMs) for energetic and material purposes combine biogenic and anthropogenic carbon cycles. In the latter, numerous manufactured products with various in‐use lifespans accumulate as anthropogenic carbon stocks. Understanding the behavior of these stocks is an important requirement to estimate not only future waste amounts, source for secondary raw materials, but also the impacts and effects in carbon emissions and carbon management. Previous models have estimated material stock changes; however, a lack of research in carbon stocks is perceived. Moreover, studies follow in‐use lifespan estimation approaches, such as decay functions, which do not coincide with observed consumption and waste treatment patterns. In the first part of this article, we present a carbon stock‐flow model to analyze inter‐relationships between carbon flows and stocks from raw materials to waste treatment processes considering a consumer perspective, where the dynamics of anthropogenic carbon stocks are completely described. In the second part, we study the pulp and paper industry in Germany under a scenario approach to analyze the behavior, development, and impacts of paper stocks and flows between 2010 and 2040. The model provided coherent results, with industrial data estimating 33.9 million metric tons in 2010 in paper stocks, equivalent to 410 kilograms per person. Consumption per capita and in‐use lifespan of products were identified as the most significant variables in carbon stock building. Model simulations show a sustained growth in stocks for the next 30 years, with increase in waste and carbon emissions. But in combination with recycling and reuse mechanisms and consumption patterns, environmental impacts are reduced.     

Dynamic Modeling of In‐Use Cement Stocks in the United States

A dynamic substance‐flow model is developed to characterize the stocks and flows of cement utilized during the 20th century in the United States, using the generic cement life cycle as a systems boundary. The motivation for estimating historical inventories of cement stocks and flows is to provide accurate estimates of contemporary cement in‐use stocks in U.S. infrastructure and future discards to relevant stakeholders in U.S. infrastructure, such as the federal and state highway administrators, departments of transportation, public and private utilities, and the construction and cement industries. Such information will assist in planning future rehabilitation projects and better life cycle management of infrastructure systems. In the present policy environment of climate negotiations, estimates of in‐use cement infrastructure can provide insights about to what extent built environment can act as a carbon sink over its lifetime. The rate of addition of new stock, its composition, and the repair of existing stock are key determinants of infrastructure sustainability. Based upon a probability of failure approach, a dynamic stock and flow model was developed utilizing three statistical lifetime distributions—Weibull, gamma, and lognormal—for each cement end‐use. The model‐derived estimate of the “in‐use” cement stocks in the United States is in the range of 4.2 to 4.4 billion metric tons (gigatonnes, Gt). This indicates that 82% to 87% of cement utilized during the last century is still in use. On a per capita basis, this is equivalent to 14.3 to 15.0 tonnes of in‐use cement stock per person. The in‐use cement stock per capita has doubled over the last 50 years, although the rate of growth has slowed.     

Material Flow Accounts and Driving Factors of Economic Growth in the Philippines

This study looks into material flow trends in the Philippines from 1985 to 2010 by utilizing the methodology of economy‐wide material flow analysis. Using domestic data sources, this study presents disaggregated annual material flow trends in terms of four major material categories, namely: biomass; fossil energy carriers; ores and industrial minerals; and construction minerals. The results describe in detail the growth of material flows in a high‐density country at the onset of its development and reveal the shift of material consumption from dominance of renewable materials in 1985 to nonrenewable materials in 2010. IPAT analysis shows that the increase in material consumption was driven by population growth from 1985 to 1998 and by growth in affluence from 1999 to 2010. However, high inequalities amidst the growing economy suggest that a small group of wealthy people have influenced the acceleration of material consumption in the Philippines. The results of this research are intended to provide a thorough analysis of the processes occurring in Philippine economic growth in order to assist in tackling implications for the important issue of sustainable resource management.     

Materials Flow Analysis of the Italian Economy

This article analyzes the mass of the materials that flowed through the Italian economy during 1994 and compares the results with a similar analysis of Germany, Japan, the Netherlands, and the United States published by a collaboration headed by the World Resources Institute. In order to perform this comparison, we have evaluated the mass of the materials produced within the country and the mass of the imported materials and commodities. For the domestic production, imports and exports, we have also evaluated the mass of the materials that accompany—as "hidden flows"—each physical flow.
Our analysis indicates that, in 1994, Italy experienced total material requirements (TMR) of 1,609 million metric tons (Mt), of which 727 Mt was used as direct material input (DMI). A comparison with other developed countries shows that the TMR and DMI flows, measured in mass per person and in mass per GDP unit, are, in Italy, lower than the corresponding figures evaluated for the United States, Germany, and the Netherlands. An interpretation of these results is presented. The analysis may give information useful for environmental considerations, although the limits of such an approach are made clear.     

Shifts in patterns and consumption of beverages between 1965 and 2002

Background: Beverage patterning may play a role in partially explaining the rising rates of obesity in the United States, yet little work on overall trends and patterns exits. Our objective was to examine trends and patterns of beverage consumption among U.S. adults. Methods: We used data from the nationally representative Nationwide Food Consumption Surveys (1965, 1977 to 1978) and the National Health and Nutrition Surveys (1988 to 1994, 1999 to 2002). To examine trends we determined percent consuming and per capita and per consumer caloric intake from all beverages. We used cluster analysis to determine year‐specific beverage patterns in 1977 and 2002. Results: The percentage of calories from beverages significantly increased between 1965 (11.8%), 1977 (14.2%), 1988 (18.5%), and 2002 (21.0%); this represents an overall increase of 222 calories per person per day from beverages, resulting largely from increased intake of calorically sweetened beverages. Beverage patterns in 2002 were more complex than in 1977 and were dominated by a greater number of beverages, reflecting the increase in alcohol, soda, and diet beverages. Conclusion: Calories from beverages increased substantially from 1965 to 2002, providing a considerable source of daily calories. Given the upward trends in calorically sweetened, nutrient‐deficient beverages and the shifts in overall beverage patterns, addressing beverage intake is a salient issue for adults.     

Cirrhosis mortality and per capita consumption of distilled spirits,United States, 1949-94: trend analysis

ObjectiveTo describe, evaluate, and suggest interpretations for an observed aggregate level relation between trends in mortality from cirrhosis and per capita consumption of distilled spirits in the United States.DesignTrend analysis using data on US cirrhosis mortality and per capita alcohol consumption.ResultsThere is a consistent long term trend relation between mortality from cirrhosis and per capita consumption of distilled spirits in the United States from 1949 to 1994. Two instances of comparatively sharp drops in the consumption of spirits earlier in the 1940s generated mixed results in predicting changes in cirrhosis mortality.ConclusionsAn aggregate level relation between trends in long term cirrhosis mortality and the consumption of spirits falls considerably short of establishing a direct causal link between the two for individuals. Moreover, two sharp drops in the consumption of spirits generated only mixed results with respect to the short term trend in cirrhosis. Nevertheless, the observed relation between the consumption of spirits and cirrhosis mortality merits further investigation.

Key messages

• US cirrhosis mortality peaked in 1973 but alcohol consumption did not peak until the early 1980s
• Both shifts in the distribution of US drinking patterns (which are not reflected in per capita consumption statistics) and the increase in the availability of treatment for alcoholism have been suggested as potential sources of the decline in cirrhosis
• The trend in the consumption of distilled spirits from 1949 to 1994 shows a close, aggregate level association with cirrhosis mortality
• This aggregate level relation suggests that research is needed into the link between the effects of specific alcoholic beverages and cirrhosis

     

Cape Town’s Metabolism: Insights from a Material Flow Analysis

This work aims to contribute to the number of urban metabolism case studies using a standardized methodology. An economy‐wide material flow analysis (EW‐MFA) was conducted on the Metropolitan Municipality of Cape Town (South Africa) for the year 2013, using the Eurostat framework. The study provides insights into the city's metabolism through various indicators including direct material input (DMI), domestic material consumption (DMC), and direct material output (DMO), among others. In order to report on the uncertainty of the data, a set of data quality indicators originating from the life cycle assessment literature was used. The results show that domestic extraction involves significant quantities of non‐metallic minerals, and that imports consist primarily of biomass and fossil fuels. The role of the city as a regional hub is also made clear from this study and illustrated by large quantities of food and other materials flowing through the city on their way to or from international markets. The results are compared with indicators from other cities and with previous metabolism work done on Cape Town. To fully grasp the impacts of the city's metabolism, more work needs to be done. It will be necessary to understand the upstream impact of local consumption, and consumption patterns should be differentiated on a more nuanced level (taking into account large differences between household income levels as well as separating the metabolism of industry and commerce from residential consumption).