Smog-Eating Tile from MonierLifetile (a Boral Roofing company) is a line of roof tiles that speeds up oxidation to reduce pollution and contaminants to the environment. The tile incorporates a photo catalytic agent (titanium dioxide) that breaks down nitrogen oxide molecules, a common pollutant from street traffic. The tile can also break down organic substances, such as dirt and algae, that are later rinsed off by rain. The concrete tile comes in four profiles: Barcelona, Villa, Saxony Slate, and Saxony Shake.