BALTIMORE (AP) — The heat wave is creating unhealthy air quality for sensitive groups across much of Maryland.

The Maryland Department of the Environment says code orange conditions are forecast for the Washington area, central Maryland and the Eastern Shore through Friday. Code orange conditions mean children and adults with respiratory and heart ailments may experience health effects and should limit time spent outside.

The federal Environmental Protection Agency says sunlight and summer heat increases the amount of ground-level ozone, one of the main ingredients in smog. Auto exhaust, industrial emissions, gasoline vapors and chemical solvents as well as natural sources contain compounds that help form ozone.

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