99% of the world’s population breathes air that does not meet air quality limits recommended by the World Health Organization. The consequences for our health are diverse, not just for the respiratory system, but for our entire body.
An article that can be found in the magazine Inserm No. 58
More than four million! According to the WHO, this is the number of premature deaths caused by outdoor air pollution each year worldwide. Respiratory obstructions and infections, cardiovascular accidents and cancers are the main causes of this premature mortality due to the presence of pollutants in the air we breathe: gases, heavy metals, suspended particles and dust. Those who have the greatest influence on our health are undoubtedly the famous prime ministers (for particle matter in English), especially PM2.5, Fine particles less than 2.5 microns in diameter. Public Health France estimates that around 40,000 premature deaths are due to PM.2.5 In France.
Immediate impact…
Whether they are of natural origin or emitted through human activities, air pollutants initially have short-term effects on our health. These are particularly noticeable during pollution peaks and in the days that follow. “ These peaks are particularly accompanied by a Increase in consultations and hospitalizations for allergies and respiratory infections », says Isabella Annesi-Maesano, epidemiologist and research director Insert Montpellier. THE Pollutants are very reactive irritants that damage the mucous membranes and promote allergic and inflammatory reactions, but also infections caused by microorganisms. » Then cases of bronchitis, bronchiolitis, pneumonia and ear infections increase. These infections can cause complications or even death in those most at risk, such as young children, the sick and/or the elderly. This has also been shown by work based on data from six Western European countries, in which Isabella Annesi-Maesano was involved Mortality associated with Covid-19 increases during peak PM levels2.5.
Over and beyond, ” Spikes in air pollution can cause a temporary reduction in our lung capacity and worsen symptoms of respiratory illnesses » adds Valérie Siroux, respiratory health specialist and Inserm research director in Grenoble. This is the case, for example, withasthma or even that chronic obstructive pulmonary disease (COPD) – a pathology characterized by progressive obstruction of the airways and lungs. Over and beyond, ” The finest particles can also penetrate deep into the bronchi, enter the bloodstream and cause breathing problems, among other things. Cerebrovascular accidents (CVA) or some Heart attack », continues Isabella Annesi-Maesano.
…like in the long run
However, the greatest health burden comes from chronic exposure to air pollution. “ We are all exposed to it from our conceptionremembers Valérie Siroux. However, it is more difficult to study these long-term health effects, which occur even at exposures considered acceptable. » To identify them, epidemiologists conduct cohort studies that track the health of thousands of people over long periods of time, sometimes decades. However, there are currently several consensuses about the contribution of outdoor air pollution to the development and/or exacerbation of chronic diseases. This is the case, for example, with lung cancer, the incidence of which is increased with continuous exposure to even relatively low PM concentrations. Air pollution was also classified as carcinogenic by the International Agency for Research on Cancer in 2013. The effects on cardiovascular and respiratory diseases have also been documented in detail. Over and beyond, ” Women exposed to air pollution during pregnancy are at higher risk of having a premature birth and/or giving birth to a low birth weight baby », specifies Valérie Siroux. Pregnancy outcomes that may contribute to neonatal mortality.
In addition, over the last twenty years, increasingly convincing evidence points to more or less strong links between air pollution and numerous health disorders and chronic pathologies: diabetes, obesity, auto diseases, immune, allergy, developmental and autism spectrum disorders, impaired cognition and neurodegenerative diseases, mood disorders, etc. So “ Use of the within the scope of theKonstanz studyA general epidemiological cohort in the general population consisting of a sample of 200,000 adults, we showed that the most exposed participants were present poorer cognitive performance in the areas of memory, language and executive functionsand this from the age of 45states Bénédicte Jacquemin, Inserm researcher in Rennes. We have also highlighted a connection between exposure to air pollutants and increased depressive symptoms. »
Continue to research health effects
Ultimately, ” Every organ in our body is affected by air pollutants, even at low doses », notes Isabella Annesi-Maesano. However, the toxicological mechanisms responsible for these health effects are not always clearly characterized. And some very harmful compounds, such as ultrafine particles, fine dust0.1, whose diameter is less than 0.1 micrometers, have not yet been sufficiently investigated. Still ” They penetrate very deeply into the body », adds the epidemiologist, who regrets that the monitoring of these pollutants is not yet regulated. Over and beyond, “We lack data on the interactions between these pollutants and theCocktail effect resulting effects, but also on the influence of other sources of pollutants and our lifestyle », notes Isabella Annesi-Maesano. Information that could be obtained by studying our Exposome, that is, all the environmental pollutants that we are exposed to on a daily basis, which would then make it possible to direct health policy to reduce the enormous health impact of air pollution. Research will not slow down.