How healthy is the air you breathe? If you live in the Fresno, Bakersfield or Visalia-Porterville-Hanford areas of California, then chances are it's not very healthy.

The American Lung Association released its annual State of the Air report Wednesday, revealing the U.S. cities with the worst air quality in terms of short-term (24-hour) particle pollution, year-round particle pollution and ozone pollution.

Cities in Southern California dominated the top of all three lists.

The report found that nearly 138.5 million people across the country (nearly 44% of the U.S. population) live where pollution levels are "too often dangerous to breathe." Various cities in the West saw record numbers of days with high short-term particle pollution, due in large part to climate change.

Heat, drought and wildfires are major contributors to high-particle conditions.

Particle pollution is particularly dangerous because it contains microscopic solids and liquid droplets that can get deep into your lungs. According to the Environmental Protection Agency (EPA), this can cause serious health problems, including irregular heartbeat, aggravated asthma and even premature death.

It's also detrimental to the environment, making lakes and streams more acidic, damaging forests and crops, and altering the diversity of ecosystems.

It isn't all bad news, however. The number of people breathing in unsafe air decreased by more than 9.1 million compared to 2010-2012, and increased standards meant continued reduction in overall ozone and particle pollution in the U.S. Thanks to the Clean Air Act, air emissions have dropped steadily since 1970. State of the Air 2015 also found that the eastern half of the nation has made progress in the reduction of year-round particle pollution.

But we still have a long way to go.

"Everyone has the right to breathe healthy air," Harold P. Wimmer, National President and CEO of the American Lung Association, said in a press release. "We must meet our air pollution challenges head-on to protect the health of millions of Americans living with asthma and chronic obstructive pulmonary disease."

The report urges federal and state leaders to protect the Clean Air Act, adopt a strong Clean Power Plan to reduce carbon pollution from power plants, revise ozone air quality standards and improve air pollution monitoring.

But you can help too. The American Lung Association suggests getting involved in community politics, speaking up for protective standards like the Clean Air Act, and reducing the amount of pollution you're responsible for by driving less.

Find the lists of cities with the most air pollution below, and find the full report here.

This week is Air Quality Awareness Week. Do your part. http://t.co/QL5asLcSC4 — U.S. EPA (@EPA) April 27, 2015

The 10 most polluted U.S. cities, by short-term particle pollution

Fresno-Madera, California Bakersfield, California Visalia-Porterville-Hanford, California Modesto-Merced, California Los Angeles-Long Beach, California San Jose-San Francisco-Oakland, California Salt Lake City-Provo-Orem, Utah Logan, Utah-Idaho Fairbanks, Alaska Pittsburgh-New Castle-Weirton, Pennsylvania-Ohio-West Virginia

The 10 most polluted U.S. cities, by year-round particle pollution

Fresno-Madera, California Bakersfield, California Visalia-Porterville-Hanford, California Modesto-Merced, California Los Angeles-Long Beach, California El Centro, California San Jose-San Francisco-Oakland, California Cincinnati-Wilmington-Maysville, Ohio-Kentucky-Indiana Pittsburgh-New Castle-Weirton, Pennsylvania-Ohio-West Virginia Cleveland-Akron-Canton, Ohio

The 10 most ozone-polluted U.S. cities