The Bay Area's air quality received mixed grades and a slight improvement overall in the American Lung Association's annual State of the Air report.
The report ranks the San Jose–San Francisco–Oakland region as the seventh most polluted by daily particulate matter, the fifth most polluted by annual particulate matter -- in front of Los Angeles -- and the 12th most polluted by ozone. Particulate matter and ozone impact health, especially in elderly residents and children.
Santa Clara County was among nine counties in California to receive failing grades from the report. The others were Sacramento, San Bernardino, San Diego, Shasta, Stanislaus, Sutter, Tehama and Tulare counties.
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Important to note the data used was from 2020-22.
“Those were some of the key years for wildfires in Northern California and had a major impact on air quality progress and exposures to harmful particle pollution in the Bay Area,” said Will Barrett, the nationwide director for Clean Air Advocacy.
While oftentimes the Bay Area's air quality decreases because of wildfires, the American Lung Association says it's not the region's No. 1 cause of air pollution.
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"The dominant cause of air pollution in the Bay Area and California tends to be the transportation sector, so from cars and trucks and buses to ships in the port or other heavy equipment," said Barrett. "And that's why these types of sources really do need to be cleaned up."
The report also ranked the cleanest cities or regions to live: Bangor, Maine; Johnson City-Kinsport-Bristol, Tennessee-Virginia; Lincoln-Beatrice, Nebraska; Honolulu, Hawaii; and Wilmington, North Carolina.
