What Is Smog?

Air Pollution and How Photochemical Smog Forms

China, Shanghai, Huangpu District, Elevated
Alan Copson/Photolibrary/Getty Images

The sun gives us life. But it also can cause lung cancer and heart attacks. Wait...did I get that right? If you look at the sun as a primary component in smog then, yes, that's right.


The Formation of Smog

Photochemical smog (or just smog for short) is a term used to describe air pollution that is a result of the interaction of sunlight with certain chemicals in the atmosphere. One of the primary components of photochemical smog is ozone.

While ozone in the stratosphere protects earth from harmful UV radiation, ozone on the ground is hazardous to human health. Ground-level ozone is formed when vehicle emissions containing nitrogen oxides (primarily from vehicle exhaust) and volatile organic compounds (from paints, solvents, and fuel evaporation) interact in the presence of sunlight. Therefore, some of the sunniest cities are also some of the most polluted.


Smog and Your Health

According to the American Lung Association, your lungs and heart can be permanently affected by air pollution and smog. While the young and the elderly are particularly susceptible to the effects of pollution, anyone with both short and long term exposure can suffer ill health effects. Problems include shortness of breath, coughing, wheezing, bronchitis, pneumonia, inflammation of pulmonary tissues, heart attacks, lung cancer, increased asthma-related symptoms, fatigue, heart palpitations, and even premature aging of the lungs and death.


How to Protect Yourself from Air Pollutants

The American Lung Association ranks some of the most polluted cities in the United States. California is ranked in 6 of the top 10 most polluted cities for ozone pollution. While you may not be able to move to a less polluted city, there are things you can do to protect yourself from the effects of air pollution.






More Information of Smog

Want to know where you should relocate to in order to avoid ground-level ozone pollution? According to the 2007 State of the Air report from the American Lung Association, The five cleanest cities are

  1. Boone, Iowa
  2. Bellingham, Washington
  3. Bloomington, Illinois
  4. Boise City, Idaho
  5. Brunswick, Georgia