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Concrete isn't usually considered an environmentalists' friend, but a remarkable new technology could soon be turning the gray stuff green.

Scientists at Eindhoven University of Technology in the Netherlands have developed a paving material that actually eats pollution, claiming it could soon become a crucial tool for improving air quality in urban areas.

The problem in many cities is that vehicle exhausts emit nitrogen oxides, which cause acid rain and smog that damages not only human health and quality of life but also the fabric of buildings.

But the new concrete is coated with titanium dioxide, which is a photocatalytic material, meaning it removes the nitrogen oxides and uses sunlight to convert them into harmless nitrate that is washed away by rain.

"In our tests we have found nitrogen oxide reductions of 35 to 40 percent in areas paved with the new concrete," Professor Jos Brouwers of the Department of Architecture, Building and Planning at Eindhoven University of Technology told CNN.

Titanium dioxide is already commonly used to coat surfaces that are hard to clean -- it is a component in some paints -- because it functions as a self-cleaning chemical, meaning the new concrete has the additional advantage that it breaks down algae and dirt so its surface stays clean.

Brouwers' discoveries are part of a race to explore new ways of using new technology to mitigate pollution. Chinese researchers are believed to be experimenting with nanotech polymers to coat exhaust pipes, and others across the world are experimenting with titanium dioxide.

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