Bay Area ranked among nation’s worst spots for air pollution

GALLERY: The nation's worst regions for air pollution GALLERY: The nation's worst regions for air pollution Photo: Instagram / Dennisk928 Photo: Instagram / Dennisk928 Image 1 of / 27 Caption Close Bay Area ranked among nation’s worst spots for air pollution 1 / 27 Back to Gallery

Even as the nation makes strides cleaning up dirty air, many parts of California, including the Bay Area, are struggling to reduce air pollution in the face of climate change.

The hordes of fossil-fuel-burning cars and trucks that have become emblematic of the Golden State are combining with overall hotter, dryer weather — and wildfires and dust storms — to fill the skies with more and more soot, according to a report released Tuesday by the American Lung Association.

The Bay Area was alongside parts of the Central Valley, which after years of improvement saw increases in the number of days with unhealthy levels of soot between 2012 and 2015, the report shows. The Bay Area ranked among the country’s 10 worst regions for what is known as particle pollution.

While much of the problem can be traced to the five-year drought, which came to an end this winter, the American Lung Association expects only temporary relief from sooty skies as the state struggles with a future marked by a changing climate.

“We were lucky to have a wet year this year,” said Bonnie Holmes-Gen, senior director for air quality and climate change with the American Lung Association in California. “That will certainly result in lower levels of particle pollution, but we know that these extreme events are becoming the new normal.”

Alongside ozone, particle pollution is one of the most widespread air pollutants. The tiny solid and liquid particles that define it proliferated with the wildfires that raged during the drought — and the lack of rain that normally tempers dust and debris from construction and agriculture.

More traditional sources of particle pollution include tailpipe emissions and power plants. The origins of the pollutant are mostly the same as ozone, though the two are generated under different conditions. Both are hazardous and pose increased risk for heart disease, lung cancer and asthma.

While the number of days that the Bay Area as a whole experienced unhealthy levels of particle pollution is not contained in the report, the region is listed as being the nation’s sixth-worst for short-term spikes in particulate matter and fourth-worst for year-round totals.

The region, as defined in the report, includes more than the nine counties that typically comprise it. Stockton is included, for example. This worsens the area’s pollution rating, though particulate matter still rose even without the inclusion of San Joaquin County.

Just a few days with pollution measuring above the federal Air Quality Index each year is enough to present a serious health risk, according to the report.

The San Joaquin Valley areas of Bakersfield, Visalia (Tulare County) and Fresno surpassed the Bay Area for particle pollution, while the Los Angeles-Long Beach region was slightly cleaner than the Bay Area.

Mirroring the national picture, most of California saw a drop in ozone, also called smog, which the American Lung Association credited to tighter state and federal environmental laws.

Still, the state’s notorious traffic congestion left it one of most ozone-polluted areas in the nation. Topping the list was the long-plagued Los Angeles area, followed by the Bakersfield and Fresno regions. The Bay Area was a distant 18th.

Between ozone and particle pollution, more than 90 percent of Californians live in areas with unhealthy air at some point in the year, according to the report.

While there is room for improvement, the American Lung Association’s 18th “State of the Air” report shows a trend of less pollution since its first publication. Since last year’s release, the number of people nationwide who were exposed to unhealthy air at some point dropped from 166 million to 125 million.

The report’s authors said it was critical that the government continue tough environmental policies like the federal Clean Air Act. The Trump administration has moved to weaken such protections.

“This is a real ongoing public health crisis,” said Olivia Gertz, president of the American Lung Association in California, “and it affects everyone.”

Kurtis Alexander is a San Francisco Chronicle staff writer. Email: kalexander@sfchronicle.com Twitter: @kurtisalexander

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