Can paving stones help cut pollution levels? Scientists in the Netherlands reckon so.
The BBC reports on so-called 'smog eating pavements' that are made up of concrete, sprayed with titanium oxide.
And it is the chemical coating that neutralizes pollutants in the air and according to scientists from Eindhoven University of Technology they have seen a 19% fall in average daily levels of pollution.
At present the cost of the paving stones are 50% higher than normal, but it is hoped that the price gap will soon come down.