New measures of material consumption.

Individuals in the United States, Germany, Japan, and the Netherlands consume an average of 45 to 85 metric tons of natural resources per year, according to a new joint report from several international environmental organizations. That is roughly equal to 300 shopping bags full of natural resources per person per week.

The report, Resource Flows: the Material Basis of Industrial Economies, adds to a growing body of alternatives to traditional accounting that aim to gauge the ecological costs of natural-resource use more accurately than basic economic indicators. Economic accounting often disregards the costs of many ecologically disruptive activities - erosion of agricultural and forestry lands, waste accumulation from mining, manufacturing, or oil refinement, and so on. But the report aims to make these "hidden" resource flows economically tangible by measuring the "Total Material Requirements" (TMR), or the sum of all resources used to produce products or services regardless of monetary value. For example, Germany's use of coal for power requires extracting and removing 29 metric tons of earth per person per year. And in the United States, agricultural production causes 15 metric tons of topsoil erosion per person per year. These are ecologically significant resource flows that are generally not reflected in market prices.

Measuring the total resource requirements of the four countries studied reveals that hidden flows make up a striking 55 to 75 percent of the total resources utilized. In other words, traditional economic accounting understates the dependence of industrial economies on natural resources by more than half - vastly underestimating the scale and consequences of economic decisions and subsequent resource flows on the environment.

In addition, the report shows that economies that rely heavily on the export of their primary natural resources are forced to pay an unfair share of the associated environmental costs, while those that are heavy importers or consumers of those resources pay less than their share. For example, countries such as Japan or the Netherlands import 50 to 70 percent of their material flow, meaning that they "gain the benefits of consuming imported resources, but the environmental cost of producing them falls on others, often developing countries, that supply them."

The study found that the four countries' levels of natural resource use - already unsustainable - have slowly increased over the past 20 years, though not as rapidly as economic activity has. With global human activity expected to expand four to five times over the next 50 years, the report concludes that there is tremendous potential for gains in efficiency and reuse, as most natural resources are still being used in an environmentally disruptive, once-through manner. Comparing a country's Gross Domestic Product (GDP) to its total material requirement, say the authors, offers an indicator of the extent to which that country's economy is - or is not - sustainable. Increasing economic efficiency enough to sharply cut back the TMR would reduce the environmental costs of primary extraction (mining, logging, farming, etc.), but also of the pollution and waste left by intermediate processing (oil refining, manufacturing, etc.) and final consumption.

The study, one of the most thorough examinations of resource flows in industrial economies to date, is a joint research effort by the U.S.-based World Resources Institute, Germany's Wuppertal Institute, the Netherlands Ministry of Housing, Spatial Planning, and Environment, and Japan's National Institute for Environmental Studies.