3. Fresno – Madera, CA
Whatever the reasons for pollution are, something needs to be done as soon as possible in this area, since it has moved from 9th to the 6th position for particle-pollution and from 7th to the 6th place when it comes to the ozone pollution. These are big changes for a period of one year, and the population of around 1.12 million people is at risk of serious diseases.
