Particulate Matter also known as “Particle Pollution” is a complex mixture of extremely small particles and liquid droplets. Particulate Matter at 2.5 microns in size or smaller can be inhaled deep into the lungs and cause irritation and corrosion of the alveolar wall, which impairs lung function3. They are also known to carry microbiomes4.
These particles are small enough to stay suspended in the air. A study conducted by Feng, Cindy et al published in the Journal of Environmental Health5 showed an increased vulnerability to influenza-like illnesses when levels of PM2.5 were above the ideal range. The data suggests that PM2.5 stays airborne longer, creating a “condensation nuclei” which virus droplets attach to. These are then inhaled by people, resulting in infection.
Thus, it is best to keep your PM2.5 levels low to minimize risk of infection.
Examples of sources of PM2.5 indoors: smoking, cooking, candles, space heaters, furnaces, and poorly-maintained HVAC system.