Millions of Americans are under air quality alerts across five U.S. states as a combination of ground-level ozone and wildfire smoke creates unhealthy atmospheric conditions. Officials in Arizona, California, Colorado, Indiana, and Michigan have issued advisories warning that the air quality could pose risks, particularly to sensitive groups.
In Arizona and California, alerts are primarily driven by ground-level ozone, which can inflame airways and exacerbate breathing difficulties. Maricopa County, Arizona, including the Phoenix metropolitan area, is under an Ozone High Pollution Advisory due to expected ozone concentrations posing a health risk. California's Imperial Valley is also experiencing an Air Quality Alert for harmful ozone pollution.
Colorado faces a more complex situation, dealing with both wildfire smoke and elevated ozone pollution. Advisories cover much of the state due to smoke from fires burning in Colorado and Utah, which can aggravate heart and lung conditions and increase respiratory symptoms. The state's Front Range Urban Corridor, including Denver, is also under an Ozone Action Day Alert, indicating unhealthy ground-level pollution.
In Indiana, an Air Quality Action Day has been declared for northwestern portions of the state, where ozone levels are forecast to reach unhealthy thresholds for sensitive groups. Southwest Michigan is under an Air Quality Alert due to forecast elevated ozone levels caused by warm temperatures and sunshine.
Wildfire smoke contains microscopic particles that can travel deep into the lungs and bloodstream, potentially damaging organs. Symptoms can include stinging eyes, scratchy throat, coughing, and chest pain. Ground-level ozone irritates the airways, increasing the risk of asthma attacks.
Health officials are advising residents to limit strenuous outdoor activity, stay indoors if smoke becomes thick, and reduce physical exertion if experiencing breathing problems. Those especially vulnerable include children, older adults, and individuals with asthma, heart disease, or other respiratory conditions. Many areas are also encouraging reduced driving and avoidance of gasoline-powered equipment to help curb pollution.
The advisories vary in duration, with some alerts issued for specific days and others extending through Wednesday. Residents are encouraged to keep windows and doors closed and avoid activities that generate additional pollution.
