Particulate Matter
About This Health Driver
Particulate matter is airborne particles of various sizes, categorized by aerodynamic diameter: PM10 (coarse particles, below 10 micrometers), PM2.5 (fine particles, below 2.5 micrometers), and ultrafine particles (below 0.1 micrometers). Indoor sources include cooking (especially gas combustion and high-heat oil cooking), candle and incense burning, cleaning activities that resuspend settled dust, HVAC systems without adequate filtration, and infiltration of outdoor particulates through the building envelope.
How It Affects Bodies
PM10 particles deposit in the upper respiratory tract, causing irritation and inflammatory response. PM2.5 particles penetrate deep into the lungs, cross the alveolar membrane into the bloodstream, and trigger systemic inflammatory responses. Ultrafine particles can translocate to the brain via the olfactory nerve. Chronic PM2.5 exposure is associated with systemic inflammation, oxidative stress, endothelial dysfunction, and immune activation. The inflammatory cascade is particularly relevant to autoimmune conditions where immune regulation is already compromised.
Where It Comes From
- Outdoor air infiltration - traffic emissions, industrial pollution, wildfire smoke entering through the envelope
- Gas combustion cooking - incomplete combustion producing PM2.5 and ultrafine particles
- Candles and incense - combustion particulates and aromatic compounds
- Dust resuspension - vacuuming without HEPA, sweeping, dusting with dry cloths
- HVAC systems - inadequate filtration, dirty ductwork, recirculated dust
- Tobacco smoke (off-parcel behavioral factor but relevant to rental/shared housing) - Tobacco smoke (off-parcel behavioral factor but relevant to rental/shared housing)
How to Address It
- MERV 13-16 air handling filtration - whole-house particulate removalMechanical
- Portable HEPA purifiers - bedroom and primary living spaceOperations
- Tight building envelope - reduce uncontrolled infiltrationEnvelope
- Electric or induction cooking - eliminate combustion-generated particulatesMechanical
- ERV/HRV with filtration - controlled ventilation with particulate removalMechanical
- PM2.5 monitoring - real-time air quality sensing with alertsOperations
- HEPA vacuum specification - prevent particle resuspension during cleaningOperations