It’s a failing grade, when it comes to the air we breathe in the Denver metro area.

That’s according to American Lung Association, which took air quality data collected at the state and federal levels and ranked counties across the country, based on two questions.

“Are you breathing good air or not – and how much is your health at risk?” said Curt Huber, executive director of the American Lung Association in Colorado.

In the new report released, called "The State of the Air," the Denver metro area received an 'F' for its level of ozone, which occurs when chemicals mix with air in the atmosphere. Denver got a grade of ‘D’ when it comes to particulates, which is air pollution most associated with the brown cloud and with forest fires. That can affect lungs, especially for those who are vulnerable, like children with asthma and adults with respiratory issues.

“Both particulate matter pollution and ozone can also cause systemic effects, so they’re associated with increased risk of stroke, an increased risk of heart attack,” said Dr. Anthony Gerber, with National Jewish Health.

The new report comes six months after the EPA instituted new standards, when it comes to the level of ozone allowed in communities.

“The ozone regulations at the federal government are a little more stringent,” Huber said.

The new regulations – put in place last October by the EPA-- were opposed by some industry groups, who called it an overreach by the agency.

Simon Lomax is an associate energy policy analyst with the Denver-based Independence Institute, which advocates limited government. He was critical of the ALA report.

“The American Lung Association publishes the same alarmist report every year to generate headlines, raise money and justify tighter federal control over local economic decisions,” Lomax said. “In fact, state health officials have criticized this group for distorting the facts and ignoring decades of major air quality improvements in Denver and other parts of the country.”

In the end, the new report on air quality shows a mixed bag for the Denver metro area.

“I think that if you look at the numbers, overall, most of the days in the Denver area, the air is safe to breathe,” said Dr. Gerber. “With that said, there are definitely days when both for particulates and ozone, we spike into that range, where vulnerable people might have trouble.”

There's a county by county breakdown of rankings regarding air pollution. You can see the full report by going to http://bit.ly/1WeJABi