Cincinnati, OH-KY-IN
- High ozone days per year: 26
- No. of days with unhealthy particle pollution: 0
- People with asthma: 179,759
- Population: 2,180,746
The Cincinnati metro area is another area with a long history of coal pollution from manufacturing and transportation.
Though the area, along with parts of Kentucky and Indiana, still has high ozone levels, the number of high ozone days is less than half the number 20 years ago due to the cleanup of coal power plants and reduction in diesel engines.
