Thus for PM2.5 fine particles (diameter less than 2.5 micrometers), "between 2010 and 2019, the annual number of deaths attributable to prolonged exposure fell from 10,350 to 6,220, a decrease of 40%", according to this "Quantitative Health Impact Assessment" carried out by the Ile-de-France Regional Health Observatory (ORS), in collaboration with Airparif, a regional air quality observatory.

For prolonged exposure to nitrogen dioxide (NO2), produced mainly by vehicles and thermal power stations or heating, the number of annual deaths "falls from 4,520 to 3,680, a drop of nearly 19%".

To carry out these assessments - which do not take into account the year 2020 and the sharp drops in pollution linked to the confinements - the ORS relied on a calculation of the "attributable risk", a statistical estimate relating to all deaths recorded those attributable to air pollution.

Insee population data was thus crossed with models based on Airparif data, with a resolution per square of 50 meters per side.

This highlights that the mortality gains concern "all territories including rural territories but are more marked in the dense zone, which is both more polluted and more populated".

The "benefit (is) particularly marked in Paris", with "a gross gain in life expectancy (of) nearly 10 months".

France is under prosecution by the European Union and was also condemned by the Council of State at the request of NGOs for exceeding air pollution thresholds, in particular NO2 in the Paris region, even if overall quality has improved at the regional level.

According to the study, the "median value" of exposure (50% of the measurements below and 50% above) of the population of Ile-de-France to PM2.5 on an annual average rose from 17.3 microgram/m3 to 11.7 μg/m3 since 2010 (the EU sets a target of 25 μg/m3) and from 32.2 to 26.1 μg/m3 for NO2 (40 μg/m3 maximum authorized by the EU ).

The gains in terms of mortality could be even greater if the new reference values ​​adopted in September 2021 by the World Health Organization (5 μg/m3 for PM2.5 and 10 μg/m3 for NO2) are reached , add the authors.

They estimate that 6,200 annual deaths linked to PM2.5 could then be avoided in the region and “around 2,350 deaths” for NO2 (some causes of death are cumulative, the two figures would not necessarily add up).

Nationally, air pollution is believed to be responsible for 40,000 premature deaths each year.

© 2022 AFP