PM10 (Coarse particulate matter)
PM10 is particulate matter 10 micrometers or smaller in diameter. Includes dust, pollen, mold spores, sea salt, and combustion particles - including all PM2.5.
Reviewed by Hayden Williams. Last reviewed 2026-05-01. Unit: μg/m³.
PM10 covers everything from human-hair-sized particles down to the finest combustion soot. Most PM10 mass concentration comes from coarse particles (2.5-10 μm) such as wind-blown dust, pollen, and mechanically generated road dust. The fraction smaller than 2.5 μm (PM2.5) drives most health effects, but the coarser particles still trigger irritation and respiratory hospital admissions during dust storms.
Health effects
PM10 irritates airways, worsens asthma, and is linked to respiratory hospitalizations during dust storms. It penetrates the upper airways but generally does not reach the alveoli or bloodstream the way PM2.5 does.
Hospital admissions for asthma and bronchitis rise during PM10 spikes. Long-term exposure is associated with reduced lung function, particularly in children. The acute mortality association is weaker than for PM2.5 but still detectable in epidemiological studies, especially during major dust events.
Vulnerable groups
Asthma sufferers (immediate trigger), people with COPD, children, elderly, and outdoor workers in arid regions or near construction sites.
Common sources
- Wind-blown dust (Sahara, Gobi, Loess Plateau, Middle Eastern deserts)
- Construction sites and demolition
- Mining and quarrying operations
- Mechanical road wear and tire/brake abrasion
- Pollen and biological particles
- Industrial fugitive dust
- Wood smoke and combustion (also PM2.5)
Regional context
PM10 spikes during regional dust events: Saharan dust transport across the Atlantic and into Southern Europe; Gobi Desert dust storms hitting Northern China and Korea every spring; Middle Eastern dust season May-September; Australian dust storms in drought years. Indoor PM10 in homes with poor ventilation can rival outdoor levels.
Regulatory thresholds
How PM10 is measured
Same instruments as PM2.5 measurement, with PM10-specific size cutoff inlets. Beta-attenuation monitors and gravimetric filter samplers are reference methods. Low-cost optical sensors increasingly report both PM10 and PM2.5 simultaneously.
How to reduce your exposure
- Stay indoors during dust storms and close windows
- Run HEPA air purifiers - they capture both PM10 and PM2.5
- Wear N95 outdoors during dust events
- Dampen dust at source on construction sites (water spray, enclosure)
- Vegetative buffers near roads reduce coarse particle infiltration
Trends
PM10 has declined in most developed economies as industrial emissions tightened, but is rising in arid and rapidly developing regions where construction and unpaved roads dominate. Climate-change-driven drought and desertification are increasing dust storm frequency in the Sahel and parts of Central Asia.
Cities where PM10 matters most
Live readings for cities historically affected by elevated PM10:
Frequently asked
What is the difference between PM2.5 and PM10?
Size. PM10 includes all particles 10 μm and smaller, which means it includes PM2.5. PM10 mostly stays in the upper airways; PM2.5 reaches deep lungs and bloodstream. Health effect literature is much stronger for PM2.5.
Is PM10 dangerous?
Yes, but less penetrating than PM2.5. PM10 triggers asthma attacks, bronchitis, eye/throat irritation, and reduced lung function, particularly during dust storms. Acute hospital admissions for respiratory conditions rise on high-PM10 days.
Does pollen show up as PM10?
Yes. Pollen grains are large enough that bioaerosol monitors and PM10 samplers both pick them up. During allergy season, pollen can be a meaningful fraction of measured PM10.
How is PM10 reduced?
Source controls: wet road sweeping instead of dry, construction site dust suppression, paved roads, vegetation buffers, industrial fugitive-dust capture. Personal protection: HEPA indoor filtration, N95 masks during outdoor dust events.
Sources + further reading
Track PM10 live across 217 cities on atmos.today. See methodology for how readings are sourced and calculated.