Question: Where Does Smog Occur?
Answer: Severe smog and ground-level ozone problems exist in many major cities around the world, from Mexico City to Beijing. In the United States, smog affects much of California, from San Francisco to San Diego, the mid-Atlantic seaboard from Washington, DC, to southern Maine, and major cities in the South and Midwest.
To varying degrees, the majority of U.S. cities with populations of 250,000 or more have experienced problems with smog and ground-level ozone. According to some studies, more than half of all U.S. residents live in areas where the smog is so bad that pollution levels routinely exceed safety standards set by the U.S. Environmental Protection Agency.
Smog: Frequently Asked Questions
