Introducing Air-Purifying Pavement
![](https://media.wnyc.org/i/800/0/c/85/photologue/photos/russia_smoke.jpg)
Russians and tourists wear facemasks to protect themselves from forest fire smog while walking on Red Square in Moscow on August 6, 2010
( Getty Images )
( Getty Images )
Produced by Cassie Jones
Hosted by Todd Zwillich