Particulate matter (PM2.5 and PM10)

Particulate matter (PM) is the set of solid and liquid particles suspended in the air. It is classified by diameter: PM10 have a diameter of 10 microns or less, and PM2.5 of 2.5 microns or less. The smaller they are, the more deeply they penetrate the body, which makes them one of the pollutants with the greatest impact on health and a key indicator of environmental impact.

PM2.5 are especially concerning because, given their small size, they can reach the pulmonary alveoli and even pass into the bloodstream. PM10, somewhat larger, mainly affect the upper airways.

Main sources

Particulate matter comes from many sources, both natural and human. Among human sources, the most notable are:

• The combustion of fossil fuels in vehicles and power plants, linked to sustainable transport as a way to reduce it.
• Industrial processes and construction.
• Building heating and biomass burning.
• Agriculture and certain burning practices.

Many of these sources coincide with those that emit greenhouse gases, so reducing particulate matter usually brings climate benefits too.

Health effects

Exposure to particulate matter is associated with respiratory and cardiovascular effects, such as worsening asthma, reduced lung function and a higher risk of heart and lung disease. Because of their deep penetration, PM2.5 are considered one of the most harmful air pollutants to human health, especially with prolonged exposure.

How it is measured

The concentration of particulate matter is expressed in micrograms per cubic metre of air (µg/m³) and measured at monitoring stations using gravimetric methods or automatic equipment. PM10 and PM2.5 are tracked separately because they partly come from different sources and have different health effects. These data feed air quality indices and make it possible to check compliance with limit values, as well as to assess the effectiveness of reduction measures.

Reference values

Reference values exist to protect health. The World Health Organization (WHO) guidelines updated in 2021 recommend, for PM2.5, an annual mean of 5 µg/m³ and a daily value of 15 µg/m³; and for PM10, 15 µg/m³ as an annual mean and 45 µg/m³ as a daily mean. In the European Union, Directive (EU) 2024/2881 sets binding limit values for 2030, stricter than the previous ones and closer to those WHO guidelines, though without matching them.

Relevance for companies

For organisations, particulate matter is relevant because their activities can be a direct source of these particles and because managing them is part of environmental compliance and sustainability reporting. Measuring and reducing these emissions usually goes together with improvements in energy efficiency and the modernisation of processes.

How Manglai can help

Manglai helps companies measure, understand and reduce their environmental impact, integrating emissions into a rigorous sustainability strategy. Discover how Manglai can help you manage your environmental footprint.