Particulate matter refers to very small solid and liquid particles in the atmosphere.
Particulate matter refers to very small solid and liquid particles in the atmosphere. There are numerous natural and anthropogenic (man-made) sources.
PM ia hazardous to human health – acute and chronic effects to the respiratory and cardiovascular systems (mortality, morbidity, health care).
There are larger effects on those with asthma, existing heart or lung diseases, senior citizens, young children, and those who work outdoors.
For more information about particulate matter and PM pollution, please visit the EPA's Particulate Matter Pollution webpage.