GREENSBORO, N.C. — Millions of people are impacted by the wildfire smoke coming from Canada. It's causing air quality alerts for 3/4 of the U.S.
Yes, it's hazy, but what makes the wildfire smoke different than other air quality concerns are the particles.
WHAT'S IN WILDFIRE SMOKE?
According to the EPA, wildfire smoke is comprised of a mix of things:
gaseous pollutants, hazardous air pollutants, water vapor, and particle pollution.
This particle pollution represents a main component of wildfire smoke and what the EPA calls the 'principal public health threat'.
Particle pollution may be called different things. Interchangeable words would be: particles, particulate matter, or simply, PM.
A particle is a general term for a mix of solid and liquid droplets in the air.
Particles can be made up of different components, including acids (e.g., sulfuric acid), inorganic compounds (e.g., ammonium sulfate, ammonium nitrate, and sodium chloride), organic chemicals, soot, metals, soil or dust particles, and biological materials (e.g., pollen and mold spores).
WHY THE SIZE OF THE PARTICLE MATTERS
Particles come in all shapes and sizes. For example, the EPA has a graphic showing the difference between a strand of human hair, fine beach sand,
as well as dust, pollen, and mold. Even smaller than all those items, are the
particles found in wildfire smoke. You can see them with a microscope.
Because they're so small, the EPA says those particles can travel deep into the lungs and may even enter the bloodstream. Large particles aren't as big a concern because they don't usually enter the lungs.