Life

Air pollution can be bad for the brain — these are the cleanest and the smoggiest places in America

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Everyone has seen photos of the terrible smog in cities like Shanghai, China or New Delhi, India. But it turns out there are problems with air pollution in the U.S. too, especially if you live in California, according to the American Lung Association's 2018 State of the Air report.

People visit the Bund which is plagued by heavy smog on January 30, 2018 in Shanghai, China.
VCG | Getty Images
People visit the Bund which is plagued by heavy smog on January 30, 2018 in Shanghai, China.

Ozone pollution, or smog (created by emissions from industrial facilities and electric utilities, vehicle exhaust, gasoline vapors and chemical solvents, according to the Environmental Protection Agency) is worse than in 2017, according to the report, released Wednesday. It also found nearly 128.9 million people live in 185 counties that earned an "F" grade for ozone.

"Near record-setting heat from our changing climate has resulted in dangerous levels of ozone in many cities across the country," says American Lung Association National President and CEO Harold P. Wimmer.

The American Lung Association did find progress was made in year-round particle pollution (caused by unhealthy particles in the air from things like wildfires, wood-burning devices, coal-fired power plants, and diesel engines) due to cleaner power plants and vehicles.

Still, the report found that there are millions of people living in cities where particle pollution is too high. Cities with the worst, year-round particle pollution include Fairbanks, Alaska and a slew of cities in California, including Los Angeles and Bakersfield.

That's all bad news because air pollution not only takes a major toll on your respiratory system — particularly on the lungs — but it has also been linked to having a negative impact on your brain. A 2015 study published by PLOS Medicine found that children attending schools with higher traffic-related air pollution had a smaller improvement in cognitive development.

Another study published in November, led by researchers at the University of Washington, found an association between air pollution and increased psychological distress, revealing that the higher level of particulates in the air, the greater the impact on mental health.

The report also recognizes the cleanest cities in the U.S.

These are the 10 worst and six best metropolitan areas when it comes to air pollution, according to the report.

Most ozone-polluted areas

1. Los Angeles-Long Beach, California

2. Bakersfield, California

3. Visalia-Porterville-Hanford, California

4. Fresno-Madera, California

5. Sacramento-Roseville, California

6. San Diego-Carlsbad, California

7. Modesto-Merced, California

8. Phoenix-Mesa-Scottsdale, Arizona

9. Redding-Red Bluff, California

10. New York-Newark, New York-New Jersey-Connecticut-Pennsylvania

Cleanest U.S. metropolitan areas (in alphabetical order)

1. Bellingham, Washington

2. Burlington-South Burlington, Vermont

3. Casper, Wyoming

4. Honolulu, Hawaii

5. Palm Bay-Melbourne-Titusville, Florida

6. Wilmington, North Carolina

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