Sulfur Dioxide - SO2
Sulfur-containing gases called sulfur oxides are formed when oil products burn.
Sulfur oxides are produced by cars, oil refineries and chemical plants, when fuels are burned that contain sulfur (like coal, oil products and wood).
How It Hurts
Sulfur dioxide constricts the airways and triggers asthma attacks. Other sulfur compounds are a big part of acid rain, acid snow and haze.