
According to Forbes, the worst metro area for Ozone pollution in the US is Los Angeles - Long Beach - Riverside. Because sunlight is the key ingredient in making Ozone, sunny California is the most prone state to its pollution. 12 cities out of the worst 25 cities are in California. Ozone causes smog in the air, and inhaling Ozone is akin to getting sunburn in your airway, causing asthma, shortness of breath, wheezing, and throat irritation. As you know, Californians are highly health conscious, and you see many jogging, biking, and walking everywhere. They might have to think about doing so with oxygen tank on their back.