Everything you need to know about air pollution in the EU

What is air pollution?

First and foremost, it is important to distinguish between indoor air pollution and ambient air pollution, as the agents responsible for indoor and outdoor air pollution are not the same. The purpose of the reform voted April is related to ambient air.

Air pollution or poor air quality is referred to when the concentration of certain harmful substances is too high.

The WHO defines a list of pollutants responsible for numerous harmful effects. The main pollutants on this list are:

Fine particules (PM)

These are a collection of particles that can be of different natures (sulphates, nitrates, ammonia, sodium chloride, black carbon, mineral dust) which are too fine to settle and therefore remain suspended in the air. They are labelled as PM and are classified according to their diameter. Thus, PM2.5 are particles that are 2.5 micrometres in diameter.

Carbon monoxide (CO)

A toxic, colourless, odourless gas produced by the incomplete combustion of carbon-based fuels such as wood, petrol, charcoal, natural gas, and kerosene.

Ozone (O3)

A gas that forms from other pollutants emitted by human activities as well as vegetation under the influence of solar activity. This is why ozone pollution is particularly noted in the summer during periods of intense heat.

Nitrogen dioxide (NO2)

NO₂ is a gas commonly released during the combustion of fuels in the transport and industrial sectors.

Sulphur dioxide (SO2)

SO₂ is a colourless gas with a pungent smell. It is produced from the combustion of fossil fuels (coal and oil) and the smelting of sulphur-containing ores.

The WHO therefore defines guidelines on the concentration thresholds not to be exceeded to avoid effects on health and biodiversity. The concentration levels are expressed in micrograms per cubic metre, noted as µg/m³.

Learn more about WHO recommendations.

Where do these pollutants come from?

To put it simply, almost all human activities contribute to pollution (although some natural elements can also cause high levels of pollution, such as a volcanic eruption or a forest fire).

Most of these pollutants are the result of the combustion of fossil fuels (coal, oil, and gas) and are therefore mainly linked to industries, particularly construction due to the production of cement and steel, or the energy sector, which requires the burning of large quantities of fossil materials. Road and air transport are another significant source of air pollution, and finally, the agricultural sector is also to be blamed.

What are the consequences of air pollution?

On human health

The invisible particles penetrate the cells and organs of our body: our lungs, heart, blood, and brain. This leads to diseases such as asthma, strokes, heart attacks, cancer, dementia, and in many cases, death.

The WHO considers air pollution to be the most important environmental threat to humans in the world. Nearly 7 million premature deaths are attributable to it annually. In Europe, this is nearly 300,000 each year.

The WHO considers air pollution to be the most significant environmental threat to humans worldwide. Nearly 7 million premature deaths are attributed to it annually. In Europe, it accounts for nearly 300,000 deaths each year.

Economic impacts

Pollution hampers productivity by affecting workers, which severely impacts overall economic activity. According to the World Bank, the loss of global GDP attributable to air pollution is estimated at 6.1%.

Additionally, the numerous diseases caused by this pollution are costly to taxpayers through healthcare systems. Air pollutants also affect agricultural yields, as indicated by the European Environment Agency, which estimates that some agricultural states have lost up to 5% of their wheat production, costing 1 billion euros.

On biodiversity

Certainly, these pollutants significantly affect ecosystems and vegetation, notably through a process called “eutrophication,” which involves the rapid growth of algae and aquatic plants, facilitated by concentrations of nitrogen oxides and ammonia in the air. When these plants decompose, they reduce oxygen levels, harming fish and other aquatic organisms. This phenomenon also leads to freshwater acidification and affects forest soils.

Key numbers to evaluate air pollution

	Good	Fair	moderate	poor	Very poor	Extremely poor
(PM2.5)	<10µg/m3	<20µg/m3	<25µg/m3	<50µg/m3	<75µg/m3	+80µg/m3
(PM10)	<20µg/m3	<40	<50	<100	<150	+160
(NO2)	<40µg/m3	<90	<120	<230	<340	+350
(O3)	<50µg/m3	<100	<130	<240	<380	+390
(SO2)	<100µg/m3	<200	<350	<500	<750	+760

Source : European Environmental Agency

The political context

Today, two main legal texts at the European Union level regulate air quality standards:

Directive 2008/50/EC sets the objectives for ambient air quality to prevent or reduce the effects of air pollution on human health and the environment as a whole. It defines measures for the assessment of ambient air quality in all Member States as well as the conditions for obtaining information on ambient air quality. The Directive aims at increasing cooperation between the Member States in reducing air pollution.
Directive 2004/107/EC is more of a technical. It sets mandatory levels of fine particles, arsenic, cadmium, mercury, nickel and polycyclic aromatic hydrocarbons in ambient air and defines methods and criteria for the assessment of concentrations of these substances in the ambient air.

In 2022, the European Commission introduced a proposal to reform this legislative package.

The main elements of this reform are:

The merger of both directives into a single text
Strengthening air quality standards by updating mandatory concentration levels of harmful substances in ambient air closer to WHO recommendations
Increasing the number of quality sampling points in European cities
The introduction of a right to compensation for people who suffer from health issues related to air pollution levels above mandatory standards.

Yet a few issues remain with the current version of the draft. For starters, the new air quality standards remain above the pollution levels recommended by the WHO:

While the current draft of the directive lowers the values for fine particles (PM2,5) from 25 to 10 µg/m3 and for Nitrogen Dioxide (NO2) from 40 to 20 µg/m3. The most recent World Health Organisation (WHO) recommendations advise not to exceed 5 μg/m3 for PM2,5 and 10 μg/m3 for NO2.
If the current draft also includes a review clause, the review of the alignment of EU’s air quality standards with WHO will not be done before 2030

Secondly, the implementation deadline is too long. The main deadline for the implementation of the new standard is the 31st of January 2029, but the current draft includes a postponement clause allowing under certain conditions to extend the deadline till 2040

To find out more detailed information see the European Council’s press release.