France reports significant long-term air quality improvements

The French Ministry for Ecological Transition released its 2025 report on outdoor air quality, marking 30 years since the LAURE law. The data shows significant long-term progress in reducing pollutant emissions since 2000. Specifically, nitrogen oxides (NOx) have decreased by 64%, particulate matter (PM10) by 51%, fine particles (PM2.5) by 57%, and sulfur dioxide (SO2) by 89%.

Despite these improvements in sectors such as transport, industry, and heating, challenges remain. In 2025, concentrations of NO2, PM10, and PM2.5 saw slight increases compared to 2024, returning to 2023 levels. Ozone (O3) levels showed no specific trend.

To complement technical monitoring, participatory science initiatives are using biological indicators. For example, the association Lauragais Nature has engaged participants in observing lichens on tree trunks. Because lichens grow slowly and accumulate traces of sulfur and nitrogen compounds over years, they serve as a natural record of long-term air quality, providing a cumulative perspective that differs from real-time electronic sensors.