This photograph shows people in London protesting the Department of Transportation. It turns out that air pollution is a major problem in British cities. This link will take you to an article on how excerising is good for you even if you live in a city that has poor air quality. 
http://www.dailymail.co.uk/news/article-3574260/Why-walking-good-smog.html 

This link will take you to a presentation on California's Smog Check Program: 
https://www.slideshare.net/lightjump/vvc-auto-855-smog-technician-level-1-california-smog-checkprogram 

James Pitts was an American chemist and researcher. Some would call him a pioneer when it comes to smog and air pollution research, especially in Southern California. He worked at UC Riverside and UC Irvine, during his time at these universities had made more than 400 scientific publications and 4 books on air pollution and smog. 

He was the director of the Statewide Air Pollution Research Center at UC Riverside. During his time there, he and a group of scientists built a state of the art smog chamber. In the chamber, they would conduct experiments with volatile organic compounds and other pollutants that come from car exhaust that react to sunlight and form ozone, which is the main ingredient of smog. 

His findings would serve as a building block for creating regulations for California's air quality laws. He would refuse funding from large industries to show that his center was unbiased. He would also translate into plain English what his research showed making it easier for people to understand. He would receive recognition on the state and national level for his work. 

James Pitts is seen as a pioneer for the study of air pollution and smog.