Toyota eco billboard air pollution
Toyota's eco-billboard 'scrubs' pollutants from the air using a titanium dioxide coating Toyota

Toyota is road testing a radical idea to clean up California's troublesome air pollution problem by using advertising billboards to act as giant filters.

The car company's eco-billboard uses 'catalytic converter-style' technology whereby its titanium dioxide coated vinyl purifies the surrounding air. Oxygen reacts with the light-activated energised surface and removes nitrogen dioxide, converting it to nitrate.

Thirty-seven eco-billboards will be placed in locations across California and San Francisco from 3 April to 28 May with the estimation that the combined 24,960 square feet of 'pollution scrubbing' surface is enough to reverse the equivalent of 5,285 vehicles' worth of nitrogen dioxide in that time.

It might seem ironic that a car company is attempting to alleviate air pollution considering vehicles on California's roads are the biggest contributors to pollution.

However, the billboards serve as part of a promotional campaign for its hydrogen-fuelled Mirai. The Mirai is a fuel cell car that emits only water vapour and its latest charge in the quest for eco-friendly vehicles that take alternative fuel.

"Toyota consistently searches for new environmental technologies across all operations. This new campaign delivers Toyota Mirai's 'vehicle of change' message on a medium that lives up to that promise," said Mark Angelacos, advanced technology general manager of Toyota North America.

This is the first time the titanium dioxide coating technology has been used in this way – although it will still take a little more before Californians can breathe a little easier as the state has the four most polluted cities in the US, according to the American Lung Association.