1: Discover the most polluted cities in the world, with 9 out of 10 located in the United States.

2: 1st on the list is Fresno, California, known for its high levels of air pollution.

3: Bakersfield, California, ranks 2nd with its poor air quality and pollution levels.

4: Fairbanks, Alaska, takes the 3rd spot due to its cold weather pollution.

5: Modesto, California, is the 4th most polluted city with high pollution levels.

6: Visalia, California, comes in at 5th place with its poor air quality.

7: Hanford, California, is the 6th most polluted city due to agricultural pollution.

8: Merced, California, ranks 7th for its high levels of pollution and poor air quality.

9: Los Angeles, California, takes the 8th spot on the list of most polluted cities in the world.