Air pollution

Air pollution is the presence in the air of substances or forms of energy that alter its natural composition and harm human health, ecosystems and property. It is one of the leading environmental health risks and is closely linked to climate change, since many of its sources also emit greenhouse gases.

Air pollutants can be primary, emitted directly into the atmosphere, or secondary, formed there through chemical reactions. The most relevant for health and legislation include particulate matter, nitrogen oxides (NOx), sulphur dioxide (SO2), ground-level ozone (O3), carbon monoxide (CO) and volatile organic compounds (VOCs).

Main pollutants

• Particulate matter (PM10 and PM2.5): small solid or liquid particles that penetrate the airways and, the finest ones, the bloodstream.
• Nitrogen oxides (NOx): gases linked mainly to combustion in engines and industrial processes.
• Sulphur dioxide (SO2): associated with burning sulphur-rich fuels and a precursor of acid rain.
• Ground-level ozone (O3): a secondary pollutant formed in sunlight from NOx and VOCs.
• Carbon monoxide (CO) and VOCs: products of incomplete combustion and of solvents, fuels and industrial processes.

Main sources

Air pollution comes from many different sources, both stationary and mobile. The most important include road transport, industry, energy generation from fossil fuels, building heating, and agriculture and livestock, which release ammonia and other precursors. Natural sources such as wildfires and dust intrusions add to these, and their weight varies widely by region and season. Cutting these emissions is connected to energy efficiency and to the development of sustainable transport, two of the levers with the greatest potential to improve urban air.

EU regulatory framework

In the European Union, ambient air quality is governed by Directive (EU) 2024/2881 of 23 October 2024 on ambient air quality and cleaner air for Europe, which recasts the previous rules and sets stricter limit values for 2030, moving closer to the World Health Organization (WHO) guidelines updated in 2021, though without matching them. The directive also strengthens air quality plans, public information and access to justice. These rules are part of the broader environmental legislation affecting companies and public authorities.

Relevance for companies and the climate

For many organisations, air pollution is a material issue: their activities generate regulated emissions and they also face reputational and compliance risks. Measuring and reducing pollutants usually goes hand in hand with cutting greenhouse gases, so environmental impact and decarbonisation strategies reinforce one another. Market instruments such as the emissions trading system (ETS) put a price on certain industrial and energy emissions and encourage cleaner technologies.

How Manglai can help

Manglai helps companies measure, understand and reduce their environmental impact, integrating emissions management into their sustainability strategy. With Manglai's carbon footprint software you can calculate your emissions and build a rigorous reduction plan.