The American Lung Association released their annual “State of the Air” report on Wednesday, and Los Angeles once again tops the list of “cities most polluted by ozone pollution”—A.K.A. smog. Even though the city has spent decades extending initiatives to improve air quality, L.A. has topped the “smoggiest city” list 25 times out of the last 26 years, according to the LA Times.
According to the American Lung Association’s report, the Los Angeles-Long Beach area has managed to reduce its high-ozone days by 33.3% over the last 30 years—that is, from 230.5 days per year (1996-1998) to 153.3 days per year (2021-2023). However, when the association ranked metropolitan areas this year, L.A. still had the most high-ozone days out of 228 areas analyzed.
What else did we learn from the “State of the Air” report?
The report states that 37% of Americans live with unhealthy levels of ozone pollution, and nearly half of Americans live in an area with unhealthy levels of air pollution. Both issues are exacerbated by extreme heat and wildfires.
L.A. isn’t the only California city seeing numbers like these. Among the country’s top ten smoggiest metropolitan areas, you’ll also see Visalia at #2, Bakersfield-Delano at #3, Fresno-Hanford-Corcoran at #5, and San Diego-Chula Vista-Carlsbad at #8.
The “State of the Air” report aggregates data from air quality monitors throughout the United States. However, less than 30% of U.S. counties have air pollution control authorities monitoring their pollutants. The majority of people in the U.S. live in counties where their ozone and particle pollution levels remain unmonitored.
What is smog?
Ground-level ozone pollution, more commonly known as smog, happens when pollutants from various sources react in the atmosphere. The pollutants can come from vehicle emissions, industrial processes, construction equipment, fossil fuels, and yes, wildfires. In a sunny city like L.A. these pollutants react with sunlight to produce “photochemical smog.”
Over the last 3 decades or so, L.A. has reduced smog with an array of strict vehicle emissions standards, cleaner public transit, and industrial regulations.
The American Lung Association likens the effects of smog to a “sunburn of the lungs.” Inhaling this powerful respiratory irritant can cause shortness of breath, coughing, and asthma attacks. They call on everyone to support the Environmental Protection Agency (EPA) in their efforts to provide air quality forecasts that protect the health of at-risk populations.
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