In its newly-released “State of the Air” 2016 report, the American Lung Association has determined that Monterey County has the best air quality in the United States while Los Angeles and Bakersfield were deemed to have the worst air in the nation.

The good news for California’s Central Coast was attributed in part to the region benefitting from coastal breezes. The same is true for Salinas County.

“California is making tremendous progress,” said Bonnie Holmes-Gen, senior director of air quality and climate change at the American Lung Association in California, according to the Associated Press. “But we have a lot more work to do.”

The report found that Bakersfield had more unhealthy days than any other city due to airborne particles being spewed out by highway traffic, diesel trucks, farm equipment and fireplaces. However, Los Angeles was the worst in terms of harmful ozone pollutants stemming from tailpipe emissions, which emit dangerous and damaging amounts of smog.

Local news site KSBW.com notes that Bakersfield and several Central Valley communities are fighting the bowl-shaped topography hemmed in by mountain ranges. It notes that representatives said the drought and high temperatures had also contributed to the stagnation of air quality in some pars of the state, probably allowing dirt particles to mix with the air.

The annual report also pointed to troubling news that that the “166 million Americans live with unhealthful levels of air pollution, putting them at risk for premature death and other serious health effects like lung cancer, asthma attacks, cardiovascular damage, and developmental and reproductive harm.”

Citing data from the U.S. Environmental Protection Agency conducted between 2011-2014, the report also found that eight out of 10 Californians – 32 million people – live in counties with unhealthy levels of ozone or particle pollution at certain points over the course of the year.

Follow Adelle Nazarian on Twitter @AdelleNaz.