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).

Discover more questions

See the FAQ

Driving towards a cleaner future: how to reduce vehicle pollution

There are 1.4 billion vehicles in circulation on the world’s roads. From the factory to the scrap yard, these vehicles require raw materials to be extracted from the earth, then emit CO2 and fine particles, which cause damage to our health and our planet. But what’s the solution? Use your car as little as possible, and opt for greener transport solutions: walking, cycling or public transport. But France is a very car-centric country. The best idea is to reduce – as best you can – how much pollution your car generates.

What is a particle filter on a car?

Fine particles are harmful to human health. They can cause or exacerbate breathing and lung difficulties, cardiovascular diseases and even neurodegenerative diseases. This health risk can be limited if car owners would fit particle filters to their vehicles. Installed on exhaust or braking systems, particle filters are anti-pollution devices which capture fine particles emitted by vehicles. There are two types of particle filters: installations designed to capture particles from exhaust fumes generated by diesel and petrol vehicles, and those designed to recover fine particles from brake wear.

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.