2. Visalia – Porterville – Hanford, CA
Are there any improvements in this area? Sadly, there isn’t, as these cities went from 4th position in 2016 to the 1st in 2017 in particle-pollution, and from 3rd to 4th spot in ozone pollution during the same period. A population of 610,828 people is at risk of diseases.
And now, let’s see the number one on our list of cities with the worst air pollution in the US.