California cities have highest levels of air pollution in US: study

California cities have highest levels of air pollution in US: study
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Seven of the country's 10 most air-polluted cities are in California, despite the state's strict environmental laws, according to a new study by the American Lung Association (ALA).

Los Angeles ranked as the most smog-filled metro area in the ALA's annual State of the Air report. The city has occupied the top spot for 19 of the 20 years that ALA has compiled the rankings.


Other Golden State cities in the top 10 are San Diego, San Francisco and Sacramento. The only metro areas on the most-polluted list outside the state are Houston, the New York City region and Phoenix.

The study comes as House Democrats are aiming to pass a bill that would commit the U.S. to cutting carbon emissions in line with the 2015 Paris climate accord. The measure would face long odds of passing the GOP-controlled Senate. President TrumpDonald John TrumpDavis: Supreme Court decision is bad news for Trump, good news for Vance Meadows trying to root out suspected White House leakers by feeding them info: Axios Pressley hits DeVos over reopening schools: 'I wouldn't trust you to care for a house plant let alone my child' MORE withdrew the U.S. from the Paris agreement in 2017.

The ALA report also found that ozone pollution has worsened across the country, with 17 of the 25 most ozone-polluted cities measuring more high ozone days on average from 2015 to 2017 than 2014 to 2016. Ozone pollution is particularly high in cities in the West and Southwest.

Of the 25 most ozone-polluted cities, 10 are in California, with three in Texas: Houston, Dallas-Fort Worth and El Paso. Colorado has two — Denver and Fort Collins — while Arizona, Nevada and Utah each appear once on the list. Seven cities east of the Mississippi River are on the list.

Only six metro areas recorded no days when smog or short-term soot pollution was at an unhealthy level: Melbourne, Fla.; Bangor, Maine; Burlington, Vt.; Wilmington, N.C.; Lincoln, Neb.; and Honolulu.