Air pollution is the largest environmental risk factor for the population health. Exposure to high levels of air pollution increases the risk of chronic respiratory diseases, cardiovascular diseases including stroke, and lung cancer. In 2016, air pollution account for 249 thousand premature deaths attributable to outdoor air pollution and another 83 thousand premature deaths attributed to household air pollution in the Americas.

In 2016, outdoor air pollution, measure as the annual mean concentration of fine particulate matter (PM ≤ 2.5 micrometers in diameter) micrograms per cubic meter (µg/m3) was 17.9 µg/m3  in the Region of the Americas, which is 1.7 times the WHO air quality guideline of 10 µg/m3. Annual mean concentration of PM25 ranges from 24.3 µg/m3 in Peru (a 2.4-fold exceedance) to 6.5 µg/m3 in Canada. The level of air pollution is higher in urban areas than in rural areas.


Indicator name: Annual mean concentration of particulate matter of less than 2.5 microns of diameter (PM2.5) [ug/m3] 

Short name: Annual mean PM2.5 concentration by areas

Data type:

Topic: Risk factors, Framework Environmental factors

Rationale: Air pollution consists of many pollutants, among other particulate matter. These particles are able to penetrate deeply into the respiratory tract and therefore constitute a risk for health by increasing mortality from respiratory infections and diseases, lung cancer, and selected cardiovascular diseases.

Definition: The mean annual concentration of fine suspended particles of less than 2.5 microns in diameters is a common measure of air pollution. The mean is a population-weighted average for urban, rural and total population in a country.

Method of measurement:  Concentration of PM2.5 are regularly measured from fixed-site, population-oriented monitors located within the metropolitan areas. High-quality measurements of PM concentration from all the monitors in the metropolitan area can be averaged to develop a single estimate.

Method of estimation: Although PM is measured at many thousands of locations throughout the world, the amount of monitors in different geographical areas vary, with some areas having little or no monitoring. In order to produce global estimates at high resolution (0.1 grid-cells), additional data is required. Annual urban and rural mean concentration of PM2.5 is estimated with improved modelling using data integration from satellite remote sensing, population estimates, topography and ground measurements.

Preferred data sources: Special studies

Expected frequency of data dissemination: Every 2-3 years

Expected frequency of data collection: Every 2-3 years