
Some particles, such as dust, dirt, soot, and smoke are large or dark enough to see with the naked eye. Others are so small, often less than one-hundredth the width of a human hair, they can only be detected using a microscope.
-Inhalable Course Particles (PM10) have a diameter larger than 2.5 micrometers and smaller than 10 micrometers.
-Fine Particles (PM2.5) have a diameter of 2.5 micrometers and smaller.
Primary particles are emitted directly from a source, such as construction sites, unpaved roads, fields, smokestacks, or fires.
Secondary particles form in complicated reactions when chemicals that are emitted from power plants, industries, and automobiles react in the atmosphere. These particles make up most of the fine particle pollution in the country.
Health: The size of particles is directly linked to their potential for causing health problems. Small particles, less than 10 micrometers in diameter, pose the greatest problems because they can get deep into your lungs, and some may even get into your bloodsteam.
PM exposure has been linked to the following health problems:
-increased respiratory symptoms, such as irritation of the airways, coughing, or difficulty breathing
-decreased lung function
-aggravated asthma
-development of chronic bronchitis
-irregular heartbeat
-nonfatal heart attacks
-premature death in people with heart or lunch disease
Visibility: Fine particles are the major cause of reduced visibility (haze) in parts of the United States, including many of our national parks and wilderness areas.
Environmental: Particles can be carried over long distances by wind and then settle on the ground or in the water. The effects of this setting include:
-making lakes and streams acidic
-changing the nutrient balance in coastal waters and large river basins
-depleting the nutrients in soil
-damaging sensitive forests and farm crops
-affecting the diversity of ecosystems
-staining and damaging stones
-Limit the use of household and personal products that cause fumes
-Conserve energy at home to reduce demands on power plants
-Do not burn leaves and other yard waste
-Do not use fire pits on Air Pollution Action Days
The information included above is provided by the United States Environmental Protection Agency.