There are buildings around the world that can actually fight air pollution. These structures are made of an innovative cement material that eats smog called TX Active. The material, which hit the market in 2006, was invented by an Italian chemist named Luigi Cassar while he was working with the Italcementi Group. As of 2014, there is an estimated 20 to 50 buildings worldwide made of the "biodynamic concrete." While this concrete is more expensive that traditional concrete, it is still cheaper than other green options. TX Active reactives with sunlight to eliminate pollution, and transforms the pollution into inert salts that are washed away by rain.