1. Fine Particulate Matter
Particles are very small objects found in the air, including dust, dirt, soot, smoke, and liquid droplets. 
Our respiratory system filters out larger particles.
Smaller particles get trapped in the lungs, while the smallest are so tiny they pass through the lungs into the blood stream.

2. Where do Particles Come From?
Primary Particles
power plants, factories, automobile exhaust, construction sites, unpaved roads, wood burning, agriculture sites
Secondary Particles
gases from burning fuels react with sunlight and water vapor and are chemically transformed into particles

3. Health Effects From Particles
Particles may trigger or cause significant health problems:
coughing and difficult or painful breathing
aggravated asthma, bronchitis, emphysema
decreased lung function
weakening of the heart, heart attacks
premature death