BALTIMORE (WJZ) — It may be getting more difficult to breathe easy in the Baltimore region.

A new report from the American Lung Association has Charm City ranked as one of the most ozone-polluted cities in the nation.

Baltimore and Anne Arundel counties received a failing grade in the annual State of the Air report.

The report analyzed ozone and particle pollution levels to come up with a grade.

Montgomery and Carroll counties both received a “D” grade in the report.