The State of America’s Air Pollution

Is air pollution in the U.S. lessening? The findings of the American Lung Association’s 25th annual State of the Air report indicate air pollution continues to worsen in some areas of the country. Nearly 40 percent of Americans (131.2 million people) live in areas with unhealthy air basins, an increase of 11.7 million people compared to last year.

Climate change plays a significant role in the increase in air pollution. Drought and wildfires contribute to particle pollution, particularly in western states. With climate change bills unlikely to pass even when Democrats hold a majority in both congressional chambers, industries will continue emitting greenhouse gases. That makes it nearly certain that next year’s ALA report will show similar results as this year’s State of the Air report.

People of Color and Low-Income Suffer More from Air Pollution

People of color (POC) and low-income communities bear the brunt of pollution. While POC are 41.6 percent of the population, they comprise 52 percent of the population living in a county with at least one failing grade. In counties with the worst grades for all three types of air pollution, they are 63 percent of the population. POC are 2.3 times more likely to live in a county with three failing grades. Sixteen million people with low incomes live in countries with a failing grade in at least one type. More than 5.4 million low-income people live in countries that fail all three types of living.

Researchers looked at the health impact of nitrogen oxide and short-term particle pollution on communities. They found that disparities between POC and whites increased between 2010 and 2019. Racial disparity for pediatric asthma attributable to nitrogen increased by 16 percent and 19 percent. Disparity for short-term particle pollution-attributable mortality rates increased by 40 percent.

Extreme heat worsens air pollution, and some areas in the Central Valley town of Fresno experience worse heat due to shade inequity. Researchers looked at the mean radiant temperature in low-income communities compared to wealthier communities in Fresno on July 11, 2023. On that day, the temperature was 111 degrees Fahrenheit. Low-income communities had a mean radiant temperature of 122.7 degrees F, while wealthier communities had a mean radiant temperature of 115.7 degrees F. Little tree cover exits in low-income communities.

The West/East Divide

There is a big gap between pollution in the West and the East, particularly for short-term particle pollution. Only four large counties this year in three states east of the Mississippi River had failing grades for short-term particle pollution. A total of 108 counties in 16 western states had failing grades. The 25 cities with the worst short-term particle pollution are in the West.

Most of the 119 counties with a failing grade for year-round particle pollution are in the West. However, the new standard reveals air pollution problems in the East, with 47 counties in 12 states east of the Mississippi River having unhealthy short-term particle pollution levels. Most cities with the worst ozone levels are in the West. California has the most metropolitan areas on the worst cities list, with 10 of the 25 most polluted cities for ozone.

The Most Polluted Air Basin

The most polluted air basin in the country is the area responsible for 40 percent of the nation’s produce and nuts. One of the counties in that region is the nation’s top dairy producer. That region is California’s Central Valley, comprising the Sacramento Valley and the San Joaquin Valley. Bakersfield, a city in southern Central Valley, made the number one spot for worst short-term particle pollution. Bakersfield also topped the worst year-round particle pollution list for the fifth consecutive year in a row. The city is in the third sport for ozone pollution.

Two other Central Valley metropolitan areas, Visalia and Fresno-Madera-Hanford, made the number two and four spots on the ozone list. Those same cities rank two and three for year-round particle pollution and two and five for short-term particle pollution. Visalia is one of 25 cities with the most unhealthy days for short-term particle pollution. However, Fresno recorded its fewest number of unhealthy days for ozone.

The Central Valley lies surrounded by the Sierra Nevada Mountains to the East, the Coast Range to the West, and the Cascade Mountains to the north. The Valley’s topography traps pollution. However, the Valley’s air pollution drivers are wildfires and agricultural burning in the summer and fall, vehicles on Highway 99 (a major state corridor), and agriculture year-round. These pollution sources emit ozone and short-term particle pollution.

One of the effects of the Central Valley’s chronic air pollution is a high asthma rate. More than 550,000 San Joaquin Valley residents have asthma, or around 20 percent of adults. One in six children in the Central Valley has asthma—one of the highest asthma rates for children in California and the country.

While some improvements in air quality occurred in the Central Valley, climate change exacerbates air pollution. Drought causes dryness, increasing agricultural waste that farmers often burn. Record-breaking heat means more energy production caused by increased use of air conditioning. The increased energy production leads to more ozone. Climate scientists predict that increased heat will continue. The Central Valley regularly sees temperatures soaring past the century mark in the summer.

Stricter Levels For Ozone

The EPA recently enacted stricter limits for short-term particle pollution. As part of the State of the Air reports, the ALA continues pushing for a more stringent limit on ground-level ozone pollution. Cars and power plants are among the two sources of ground-level ozone pollution. The non-profit organization encourages people to sign the petition urging the EPA to enact stricter limits.

Image credit: Tom Schueneman. All rights reserved.

Gina-Marie Cheeseman
Gina-Marie Cheeseman
Gina-Marie Cheeseman, freelance writer/journalist/copyeditor Twitter: @gmcheeseman

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