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DENVER — The American Lung Association is out with its State of the Air 2018 air quality report, and it’s not good news for Denver.  The Mile High City is the 14th most polluted city in America for high ozone.

Seems Denver’s notorious “brown cloud” is leaving a black mark on the city.   The biggest causes?  Our increasing traffic problems, our expansive oil and gas industry, and our location.  All that bad stuff in the air gets trapped against the mountains, with nowhere to go.

“And it all mixes and in some areas we have the right mix of geography and pollutants to create an ozone problem,” said Dr. Anthony Gerber, professor and pulmonologist at National Jewish Health in Denver.  He says bad air doesn’t just cause breathing problems.

“It’s known that ozone and particulates can also promote heart attacks and strokes so on days with high ozone there’s a risk of having those kind of events as well,” Gerber added.

Toxic smog is a topic FOX 31’s Jeremy Hubbard learned a bit more about when he traveled to Asia earlier this spring.  He visited Beijing, where millions of people walk around in surgical masks to avoid the toxic smog.  It`s estimated in China, more than a million people die every year from air pollution.

In fact, on the day Hubbard visited Beijing back in March – his iPhone actually gave him a warning in the weather app – it said “very unhealthy air quality.”

Maybe Denver should have that periodic warning too.  As this tweet points out – on part of at least one day – back in January – our air quality was actually worse than Beijing’s.  A lot worse.

“I do know that (China has) many days with higher ozone than we do, they have more days that are unsafe.  And so I think its fair to say we’re not as bad as other places, but we need to continue to be as good as we can be,” Gerber said.

Ok, so maybe we haven’t reached the point where thick, yellow smog rolls into downtown list a dust storm.  Where it’s so dense – it actually grounds flights and strands travelers like it has in China. But our new ranking on the most polluted cities list is as ugly as that dirty cloud that so often shrouds our Mile High horizon.

“We all need to work together to try and reduce the chemicals that contribute,” Gerber said.

Fort Collins fared slightly better in the air quality report – but not much better.  It has the 19th most polluted air of any city in America.  But there is some good news: towns like Steamboat Springs, Pueblo and Grand Junction actually made the list for cities with the cleanest air.