Sulfur Dioxide



What is it?
Sulfur dioxide is a colorless reactive gas that is produced when coal and oil are burned. High levels are found near large industrial complexes. Examples include power plants, refineries and industrial boilers. This gas affects those who have asthma because extended exposure can cause other respiratory illnesses.  


Emission sources
  • Burning coal and oil at a power plant 
  • Copper smelting 
  • Volcanic eruptions  

Emission sources
  • Breathing it in 
  • Working where it is produced 
  • Working in the manufacturing of sulfuric acid, paper, food preservatives or fertilizers 
  • Living near an industrial area where sulfur dioxide is produced  

Health effects
  • Exposure at high levels can be fatal 
  • Burning of nose and throat 
  • Difficulties breathing 
  • Blockage of airway 
  • Decreased lung function with extended exposure 
Who is at risk? 
  • People who have asthma have an increased risk of negative health effects from sulfur dioxide.  
  • Children still growing and active outdoors may experience more health problems. 
  • People living in urban areas or near industrialized areas have a high chance of being exposed to sulfur dioxide.