Six California Cities Among The Top 10 'Most Polluted' In America

Some cities in America are more polluted than others. Factors such as factories, transportation, forest fires, and more contribute to the amount of pollution contained in a specific region.

According to a list compiled by World Population Review, the most polluted cities in California in order from most to least polluted are Los Angeles, Visalia, Bakersfield, Fresno, Sacramento, San Diego, and the San Jose-San Francisco-Oakland region. Los Angeles is ranked as the most polluted city in the entire country.

Here is what World Population Review had to say about compiling the data to determine the most polluted cities in the entire country:

"In order to determine how polluted the air is, the concentration of PM2.5 particles is evaluated. Fine particulate matter 2.5, or PM2.5 refers to tiny droplets or particles in the air that are two and one-half microns or less in width. PM2.5 is small enough to enter the bloodstream through the lungs and can lead to death. These particles come from car, truck, bus, and off-road vehicle exhausts; operations that involve the burning of fossil fuels such as heating oil, wood, or coal; or from indoor sources such as smoking tobacco, cooking, burning candles, or fireplaces."

For a continued list of the most polluted cities in America visit worldpopulationreview.com.