How much raw material does it take to support you? If you’re an average African, about 3 metric tons (3.3 tons) — the equivalent of an elephant’s worth of biomass, fossil fuels, metal ores and nonmetallic minerals — per year. But if you’re an average North American, make that a whopping eight elephants.

And those elephants are getting heftier. Even as a growing population puts more pressure on Earth’s resources, we’re becoming less efficient in our use of raw materials — essentially using more than ever to generate a specific amount of economic activity. That’s according to “Global Material Flows and Resource Productivity,” a report released recently by the United Nations Environment Programme that summarizes trends in material use worldwide.

The report reveals some startling patterns in the use of materials around the world. Total materials use tripled between 1970 and 2010, from 22 billion metric tons (24 billion tons) to more than 70 billion metric tons (77 billion tons). Even more unsettling, per capita materials use grew from 7 metric tons (7.7 tons) to 10 (11) in 2010. And overall material efficiency — the amount of raw material needed per unit of GDP — has actually decreased worldwide since 2000.

In addition to increases in overall consumption, the flow of materials has also shifted. Materials increasingly are being shipped around the world as individual countries become specialized sources of particular resources. Between 1970 and 2010, according to the report, direct trade increased fourfold.

If we continue on the current trajectory, the report predicts, we’ll be using nine times as much material in 2050 as we are today — and with that, similarly multiplying the production of environmental-harming by-products such as waste, air and water pollution, and greenhouse gases.

Introducing a new indicator, “material footprint of consumption,” the report shows clearly that the entire world can’t consume at the level of the richest among us. It encourages policy-makers and others to work to boost material efficiency and to set into place policies that incorporate social and environmental costs into the price we pay for natural resources.

“Decoupling material use and related environmental impacts from economic growth is essential for ensuring the prosperity of human society and a healthy natural environment,” the report concludes. “A prosperous and equitable world calls for transformative changes in lifestyles and consumption behavior.”

Download “Global Material Flows and Resource Productivity” or a summary for policy-makers here. View Ensia homepage