particulateair

Particulateair refers to air that contains suspended particulate matter (PM), a mixture of solid particles and liquid droplets in the atmosphere. Particles vary in size, composition, and origin. The most widely used size distinctions are PM10 (diameter of 10 micrometers or less) and PM2.5 (diameter of 2.5 micrometers or less). Ultrafi ne particles (less than 0.1 micrometers) also occur and can penetrate deeply into the respiratory system.

Sources include natural processes such as dust storms, pollen, sea spray, wildfires, and volcanic ash, as well as human activities including vehicle exhaust, industrial emissions, power generation, construction, and agricultural practices.

Health effects: Inhaled particulate air can irritate the eyes, throat, and lungs; PM exposure is linked to respiratory and cardiovascular diseases, reduced lung function, and increased mortality, especially for vulnerable groups such as children, the elderly, and people with preexisting conditions. The health impact depends on particle size, composition, and exposure duration.

Measurement and regulation: Air quality is monitored with stations and instruments that report PM concentrations in micrograms per cubic meter (μg/m3). Guidelines and legal limits exist in many regions, including World Health Organization recommendations and national standards such as the US EPA National Ambient Air Quality Standards and EU limits.

Mitigation: Reducing emissions, improving filtration, urban planning, and public advisories can lower exposure. Personal actions include avoiding outdoor activities during high pollution episodes and using masks or indoor air purifiers.