Millions of Americans have been urged to avoid drive-thru lanes amid concerns over high air pollution levels .

The National Weather Service (NWS) has issued air quality alerts in Texas, Arizona, Oregon, Washington and Montana on Wednesday.

The warnings mean ground-level ozone and particulate concentrations are forecast to reach dangerous levels. In some areas, the pollution comes from drifting wildfire smoke.

Why It Matters

The NWS warned that the general public as well as sensitive groups—children, seniors and individuals with preexisting respiratory or heart conditions—might experience health effects linked to poor air quality in the affected regions.

"Ozone is an air contaminant which can cause breathing difficulties for children, older adults, as well as persons with respiratory

See Full Page