LOS ANGELES (CBSLA.com) — Findings of a study released Wednesday showed the Los Angeles-Long Beach metropolitan area continues to have the worst ozone pollution in the nation.

According to the American Lung Association’s State of the Air 2016 report, the Los Angeles-Long Beach area ranked worst in terms of ozone pollution, ninth-worst for short-term particle pollution, and fourth-worst for annual particle pollution.

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California cities dominated the top-10 list of the worst offenders in all three categories.

“More than 80 percent of Californians, 32 million residents, still live in counties with unhealthy air during certain parts of the year,” said Olivia J. Diaz-Lapham, president/CEO of the American Lung Association in California. “We simply must do more to protect the health of Californians.”

However, researchers clarified that Los Angeles had its “best air quality ever in the history of the State of the Air Report.”

Results of the study also showed Southern California has seen a 90 percent reduction in particle pollution over the history of the report. In addition, since the year 2000, the county has also cut unhealthy ozone days by 34 percent.

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“These are tremendous gains but the fact that we are still No. 1 in the country for ozone pollution goes to show that we still have a long way to go,” said John Yi of the American Lung Association.

Yi says the drought only hurts air quality but more frequent use of public transportation and zero emission vehicles are helping.

But some hikers say, even on nice days, the pollution is clear.

“When you get to the top and you look out and you just see that layer of smog, it’s very disconcerting,” one woman said.

The report is based on readings taken at monitoring sites across the country from 2012-14.

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