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Chicago, First U.S. City to Line Streets with Smog-Eating Cement

There are many sustainable technologies designers can utilize these days to make a project more Earth- and people-friendly, but smog-eating cement isn't the most talked-about - until now. The City of Chicago is pioneering the use of a revolutionary type of cement that is capable of eradicating the air around it of pollution, potentially reducing the levels of certain common pollutants by 20 - 70% depending on local conditions and the amount of exposed surface area.

Read more on this revolutionary material after the break...

Photocatalytic cement isn't exactly news - it was developed by the leading Italian cement maker Italcementi for the Vatican in honor of the 2,000th anniversary of the Christian faith. The Seat of the Catholic Church commissioned the construction of a new church to commemorate the event and wanted surface material that would retain its new appearance despite Rome's high levels of air pollution.

The cement that Italcementi developed uses titanium oxide that, when exposed to natural sunlight, triggers a chemical reaction that catalyses the decomposition of dirt or grime on the cement's surface; thus, it is self-cleaning. What further research in Europe uncovered, however, was that this cement possessed pollution reduction properties that not even Italcementi could have foreseen, capable of cleaning up smog in adjacent air - up to 2.5 meters away - by breaking down the nitrogen oxides which are the result of burning fossil fuels.

Naturally, this makes the photocatalytic cement a perfect paving material as it successfully reduces the amount of toxins expelled by vehicles and inhaled by pedestrians. Italy and other areas of Europe have already paved many of their roads with the revolutionary material, but Chicago is reportedly the first city in America to adopt it, laying down a thin, permeable pavement for the bicycle and parking lanes on Blue Island Avenue and Cermak Road. 

The cement could eventually become an integral part of the urban environment in this country, especially since the United States is notorious for its car culture. Whether or not the cement is cost-effective remains to be seen, but it is certainly a technological step forward towards a cleaner and healthier urban environment. 

Reference: Design Build Source 

Cite:Barbara Porada. "Chicago, First U.S. City to Line Streets with Smog-Eating Cement" 14 Apr 2013. ArchDaily. Accessed . <>