published on May 11, 2017 - 11:40 AM
Written by David Castellon

The American Lung Association has issued its report detailing the U.S. metropolitan areas with the worst air quality in the country, and South Valley communities continue topping those lists.

“The Los Angeles, Bakersfield and Visalia metropolitan areas top the list of the most polluted in the country for ozone pollution and particle pollution, with many other California cities among the top-10 polluted areas,” including the Fresno-Madera and Modesto-Merced areas, according to the summary of the State of the Air 2017 report the Lung Association released Wednesday.

“More than 90 percent of Californians live in areas with unhealthy air at some point during the year, a serious public health concern at a time when the federal government is considering rolling back clean air protections,” it states.

In comparison, on a national level, nearly four in 10 Americans live in counties that have unhealthful levels of ozone or particulate pollution, according to the Lung Association.

“Our state’s air quality continues to hit unhealthy levels each year, putting Californians at risk for premature death and other serious health effects such as asthma, COPD [chronic obstructive pulmonary disease] and lung cancer,” Olivia Diaz-Lapham, president and chief executive officers for American Lung Association in California, said in a written statement.

“We are seeing continued improvement in parts of the state, but there are too many areas where residents are breathing dirty air, and we must work to reduce the sources of air pollution.”

This latest air-quality survey is based on ozone and particulate data collected over three years, from 2013 to 2015, so the rankings don’t reflect air issues after that time.

In one list, the Los Angeles-Long Beach metro area ranked worst in ozone levels, followed in order by Bakersfield, Fresno-Madera, Visalia-Porterville-Hanford and Modesto-Merced.

In short-term particle pollution, Bakersfield had the worst air over a single day, followed with a tie between Fresno-Madera and Visalia-Porterville-Hanford, and then Modesto-Merced.

For year-round particle pollution, the order changes slightly, with Visalia-Porterville-Hanford topping the worst-air list for the first time in the 18 years that the report has been generated, followed by Bakersfield and Fresno-Madera.

Ranking fourth was San Jose-San Francisco-Oakland-Stockton – put together as one metro area despite Stockton being in the Central Valley, not in the Bay Area, as are the other cities — followed by Los Angeles-Long Beach at fifth and Modesto-Merced at sixth.

Despite its consistent rankings in the worst-air categories, “California’s most populous metro area, Los Angeles, continues to improve, posting its lowest number of unhealthy days for ozone pollution and lowest levels of year-round particle pollution. Unfortunately, the region still leads the nation in unhealthy days for ozone pollution, followed by Bakersfield and the Fresno-Madera area,” the report continues.

“Bakersfield topped the national list for the number of unhealthy days for short-term particle pollution and came in second for unhealthy days for ozone pollution and year-round particle pollution levels.”

Among the other findings in the report:

– Eight cities — Visalia, Los Angeles, Bakersfield, Modesto-Merced, Sacramento, El Centro, San Jose-San Francisco and San Luis Obispo — had their fewest average unhealthy days for ozone pollution in the 18-year history of the report.

– Four Valley counties showed increases in the number of unhealthy days for particle pollution, with Visalia and Stockton having their worst showings.

– Bakersfield, Los Angeles, the Bay Area, and Sacramento had increases in unhealthy days for particle pollution.

– Year-round levels of particle pollution increased in Bakersfield, the Bay Area, Visalia, and San Luis Obispo, all of which failed to meet the national standard for reducing year-round particle pollution for the first time.

– The San Joaquin Valley is home to the four most particle-polluted cities in the U.S.

– Despite more steady progress on ozone reduction, residents in three Valley counties face more than 90 unhealthy ozone days per year.

The report didn’t list those counties.

Despite the poor report card on air quality, the researchers stated that efforts to reduce air pollution — including actions stemming from the federal Clean Air Act — are having an effect, as a quarter fewer people were living in areas where air quality hit unhealthy levels compared to levels cited in the 2016 report.

“As the economy continues to grow, overall air emissions that create the six most-widespread pollutants continue to drop,” states the report.

As for the cities with the cleanest air, few were in California, and only Salinas appeared in the lists of cleanest metro areas for ozone pollution and year-round particle pollution, though it didn’t appear in the list of cities with the lowest short-term particle pollution.

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