Maryland Attorney General Brian Frosh filed a lawsuit Wednesday against the Environmental Protection Agency. State officials say the EPA is not enforcing the Clean Air Act in five upwind states, and that creates an unhealthy level of smog in Maryland, particularly in the Washington and Baltimore metro areas.

According to the lawsuit, 36 power plants in Indiana, Kentucky, Ohio, Pennsylvania and West Virginia are releasing an illegal quantity of nitrogen oxides into the air. That increases the amount of ozone in Maryland’s air, putting the state in violation of federal law.

Frosh said that’s a problem for both the environment and residents’ health.

"When you breathe polluted air you're at much greater risk for pulmonary diseases, cardiac diseases,” Frosh said. “The power plants in those states endanger the health of Marylanders. Period."

Those upwind power plants already have the technology to control the level of pollutants they release, but they aren’t using them, state Secretary of the Environment Ben Grumbles said in a statement. He said using those controls would “level the playing field for businesses.”