So it's not just about trading clean air in Pittsburgh for foul air in Beijing. (jeffrubinssmallerworld.com)
Oil refineries, coal plants, cement kilns and other heavy industries have for years fouled the air with toxic pollution, leaving residents who live nearby with a difficult choice: stay inside or venture out and risk becoming sick from breathing air that's full of pollutants that can cause lung and heart disease, cancer, brain damage — and even death. (earthjustice.org)
The stock configuration on the 2014 + C7 Corvette Stingray pulls fouled air from the valve covers to evacuate crankcase pressure... (weaponxmotorsports.com)