Stay indoors advisory issued for over half a million people,
Hundreds of thousands of Americans have been warned to stay inside for several days this week as toxins that can harm the lungs fill the air in the Midwest.
Air quality meters registered increasing levels of fine particulate matter across a 100-mile swath of Kansas and northern Oklahoma on Tuesday morning.
The US Environmental Protection Agency (EPA) and other independent air quality monitors found the worst of the plume over Wichita, Kansas, where the air was deemed ‘unhealthy’ for anyone spending an extended period of time outdoors.
Wichita’s greater metropolitan area is home to more than 600,000 people, and approximately 750,000 live within the affected area, which stretches from Sterling, Kansas, to the Flint Hills east of Wichita.
Rising levels of PM2.5 have driven the air pollution warning, microscopic particles of toxic compounds or heavy metals often produced by factories and car exhaust, small enough to penetrate deep into the lungs.
In busy, congested areas, PM2.5 causes inflammation, breathing difficulties and other health issues when inhaled consistently.
Forecasters at AccuWeather have warned that the air in Wichita is projected to stay in the ‘unhealthy’ range until at least Friday.
According to the World Air Quality Index project, a nonprofit providing real-time air pollution data for hundreds of countries, the air quality index (AQI) in Wichita reached 172 at 7am ET. Readings between 151 and 200 impact everyone, and health officials urge the public to stay inside and limit outdoor activity.
AccuWeather’s air quality trackers also reported that PM10 levels had reached ‘unhealthy’ levels throughout the region.
PM10 is a type of particulate matter made up of tiny solid particles or liquid droplets floating in the air that are less than 10 micrometers in diameter, thinner than a human hair.
This form of air pollution is noticeably larger than PM2.5, however, both can damage the lungs, worsen respiratory issues such as asthma and contribute to heart attacks and strokes that cause premature death.
As for the cause of the polluted air in the Midwest, air quality-tracking website IQAir spotted multiple wildfires to the east of Wichita, with local wind patterns pushing the smoke towards more populated areas west.
Specifically, IQAir reported wildfires near Claremore, Oklahoma and in Longton, Clements and Allen, Kansas.
AccuWeather warned: ‘Health effects can be immediately felt by sensitive groups. Healthy individuals may experience difficulty breathing and throat irritation with prolonged exposure. Limit outdoor activity.’
Sensitive groups include anyone with heart or lung disease, older adults, children and pregnant women, who could all be especially at risk to concentrated air pollution.
In terms of the severity of Tuesday’s alert, ‘unhealthy’ air quality sits in the middle of the EPA’s alert system. There are two levels beyond unhealthy, known as ‘very unhealthy’ and ‘hazardous.’
The toxins from smoke and smog can often get trapped over cities for hours or days, depending on the local atmospheric pressure, creating a condition called stagnant air.
Pressure is measured in millibars, with normal sea-level pressure being 1,013 millibars.
Anything between 1,015 and 1,020 millibars is considered a high-pressure system, with strong pressure exceeding 1,030 millibars, especially in the winter or on colder days.
Atmospheric pressure in Kansas had pushed beyond 1,020 Tuesday morning. The combination of high pressure and little to no wind can trap pollution near ground level.
