Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
Particulate matter refers to tiny solid or liquid particles suspended in the air, such as dust, soot, and smoke. These particles can be harmful when inhaled and can contribute to respiratory issues and air pollution.
A type of air pollution caused by a mixture of particulate matter, ground-level ozone, and other pollutants.
Aerosols: Tiny liquid or solid particles suspended in the atmosphere that can have both natural (e.g., volcanic ash) and human-made (e.g., industrial emissions) sources.
Fine particulate matter with a diameter of 2.5 micrometers or smaller that is particularly concerning for human health due to its ability to penetrate deep into the lungs.