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A Few Causes of Air Quality Dangers

March 9, 2025 at 03:04 PM EDT
By WeatherBug Meteorologist, Andrew Rosenthal
This smog shrouded plane gets ready at Beijing's airport.

Cough! Cough! Cough! Air quality is bad today. This means that there are pollutants in the atmosphere. These pollutants show up as haze or smog (smoky fog), and can cause respiratory and heart problems, as well as aggravating asthma. But what are some of these pollutants that can lead to air quality dangers?

Ozone

Ground-level ozone is formed when hydrogen, carbon dioxide, and nitrogen oxides released from cars, trucks, power plants, and other combustion systems combine in sunlight and heat. While ozone is a good thing in the stratosphere - - well above the earth`s surface - - high concentrations of it near the surface can cause our breathing capacity to decrease.

Particles

Numerous particles can cause bad air quality. These include sulfur caused by ash from a nearby fire, large carbon particles from cars, trucks, power plants and combustion engines, or dust blowing from a nearby field. Any of these particles can become suspended in the air you inhale and could make breathing much more difficult.

Chemicals

Various chemicals are released from plants and combustion engines. During the hot weather and light winds of summer, these chemicals are unable to mix with the atmosphere and thus build up in large enough concentration to be breathed into your lungs. These chemicals include, but are not limited to, carbon monoxide, sulfur dioxide and nitrogen dioxide.

To help warn Americans as to air quality dangers, the EPA has created a color-coded Air Quality Index (AQI) that categorizes the air quality from good ("code green") to hazardous ("code maroon"). "Orange," "red", "purple" and "maroon" scale air quality leads to an advisory being issued to warn of these dangers.