FAQ

What is the main cause of air pollution?

As we inhale 15,000 litres of air every day, we are continually exposed to air pollution, especially in large cities. These gases and fine particles are not only harmful to our health, but they also damage the environment and ecosystems and accelerate climate change. Where does air pollution come from? Although pollutants may be of natural origin: pollens, forest fires, sand mists, soil erosion, and volcanic eruptions generate pollution over which we have very little control, human activity is the main source of air pollution. That is evidenced by the sharp decline in air quality from the 19th century, with the development of industry and road traffic.

Pollutants generated by humans

Human activity generates primary and secondary pollutants. But how are these different? Primary pollutants come straight from sources of pollution such as industry, heating, transport and agriculture. They include nitrogen oxides (NOx), sulphur dioxide (SO₂), volatile organic compounds (VOC), hydrocarbons and fine metal particles (lead, cadmium, etc.). Secondary pollutants are created in the atmosphere, as a result of chemical reactions between various pollutants that produce ozone, nitrogen dioxide and ultrafine particles.

Industries responsible for air pollution

How do we generate air pollution?

Leading the pack is the residential sector, especially home heating, and road transport. But it’s not the same up and down France. These activities are therefore respectively responsible for half and a quarter of fine particle emissions in Ile-de-France. Whereas in Haute-Savoie, in the Arve valley, 80% of polluting emissions come from individual wood heating systems.
Industry also plays a major role in air quality. Factories contribute to pollution with sulphur dioxide (SO₂), non-methane volatile organic compounds (VOCnM), PM10 fine particles and even nitrogen oxide (NOx) in France. Airparif estimates that more than 50% of sulphur dioxide pollution in Ile-de-France is generated by industrial activities.
As for agriculture and forestry, they are not far off as the main sources of air pollution. Spreading, livestock effluents, etc. represent 93% of ammonia production (NH3), 42% of NMVOC emissions, 25% of PM10 emissions and 11% of PM2.5 emissions, according to the SECTEN 2021 report by Citepa.
Non-road transport methods aren’t all squeaky clean either, especially planes. In addition to the CO₂responsible for global warming, aeroplanes generate air pollution with fine particles, especially those related to nitrogen oxides (NOx), contrails, sulphur dioxide (SO₂), and carbon particles.

A key public health problem

Air pollution is a major concern for both public health and the environment. We need to understand where it comes from and pinpoint the main sources of air pollution to arm ourselves better in the fight against this scourge that causes at least 40,000 deaths each year in France. But to finish on a positive note: In France, atmospheric pollution emissions are down since 1990 (heavy metals, acidifying and eutrophication pollutants, particles, and persistent organic pollutants).

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What are fine particles?

The term “fine particle” refers to an aggregate of polluting chemical compounds created during combustion, friction or chemical reactions. Forest fires, volcanic eruptions, and desert dust: fine particles can occur naturally. But most fine particles are generated by human activity. How? Mainly from road traffic (exhaust gases and abrasion caused by brakes on tyres and the road), home heating, and industrial and agricultural emissions.

How can you protect yourself from fine particles?

When they are inhaled, microscopic fine particles are toxic in how they can affect the lungs, heart, and cells. They can cause inflammation and exacerbate the risks of respiratory, pulmonary, cardiovascular diseases and even various types of cancer. To combat these emissions and the diseases they cause, there is a need for far-reaching public policies. Some measures are easy to implement, such as limiting the use of cars, capturing brake particles, avoiding congested areas, finding out about air quality indicators and taking care to protect your respiratory and pulmonary health.

What can we do to fight against air pollution?

One in five deaths around the world is attributable to outdoor air pollution yet politicians are struggling to remedy the situation. In France, the government has even been found at fault by the Court of Justice of the European Union and the French Council of State for not doing enough, while air pollution causes more than 40,000 premature deaths every year. What’s to blame? Natural phenomena certainly contribute (pollen, forest fires, soil erosion, volcanic eruptions, etc.), but most of the damage is caused by human activity (agriculture, industry, transport, construction, etc.), which generates gases and fine particles. In some parts of France transport is the worst culprit, in others, agriculture comes top of the list. In the fight against outdoor air pollution in France, measures must now be taken on domestic heating and road transport, which are respectively responsible for half and a quarter of fine particle emissions in Ile-de-France.