Particles and Your Health
Particles and Your Health What is particulate matter? Particulate matter (PM) is a complex mixture of solid and liquid particles that are suspended in air. These particles typically consist of a mixture of inorganic and organic chemicals, including carbon, sulfates, nitrates, metals, acids, and semi-volatile compounds. The size of PM in air ranges from approximately 0.005 to 100 micrometers (µm) in diameter – the size of just a few atoms to about the thickness of a human hair. Researchers have defined size categories for these particles differently. For the purposes of this fact sheet, PM is defined by three [...]