Where does air pollution come from?
Christian George, CNRS research director : We first distinguish pollution with ultrafine particles, linked to transport, industrial activities, daily activities such as wood heating or the use of household or cosmetic products. It can be very intense in winter in urban centres, due in particular to combustion and heating methods. Then there is ozone pollution with numerous alerts in summer: under the action of the sun’s rays, nitrogen dioxide and volatile organic compounds (butane, ethanol, acetone, etc.) present in the air will form ozone. These peaks will increase with global warming.
More than 40,000 deaths each year in France, this figure challenges…
Indeed, overexposure to polluted air, more common in the city, can cause respiratory but also cardiovascular problems, in particular because of the fine particles which will succeed in penetrating the blood system to subsequently reach the heart and the brain. . The problem has arisen since the industrial era and the development of the automobile. A landmark episode, that of 1952, in London: 12,000 people then died due to the smog (thick fog formed of fine particles and ozone) caused by the fumes from coal stoves.
Has the topic been downplayed?
The State and Europe have been imposing regulations for decades. In the automobile, the catalytic converter was made compulsory in Europe in the 1990s in order to limit the exhaust gases in the air. Leaded fuel was then gradually banned. These measures have contributed to improving air quality. But we have not sufficiently taken into account the new aspects of this pollution.
That’s to say ?
Initially mainly caused by the combustion of coal and the automobile, pollution now emanates from household products, perfumes or even PFAS (synthetic chemical substances used for non-stick coatings, food packaging, etc.). We are not yet able to measure the risks of these sources present in the air.
Is the population aware of the issue?
Not necessarily ; the population often becomes aware of this danger during pollution peaks or when there are bad smells. But when measures are put in place, such as Low Emission Zones (ZFE) reserved for the least polluting vehicles, the population perceives them as restrictive, without understanding their importance.
What should be done ?
Pursue public policies to limit polluting vehicles, be vigilant about emerging pollution and ensure, for example, heating with approved wood. But without wishing to appear too pessimistic, there will always be polluting emissions, as soon as there is human activity.