Atmosphere, air quality and impacts
This area retains a structure close to that proposed during the previous period. It mainly concerns the characterization and study of the fate of gaseous pollutants and aerosols in the atmosphere. The objectives are to identify the impact of these pollutants on air quality, climate and health. The health aspect will be reinforced during this period and the study of pollution biomarkers will be treated.
For the next five-year period, this scientific field will be based largely on the themes of the labexCaPPA scientific project, the request for renewal of which is in progress. CaPPA brings together 7 laboratories, including LOA, PC2A, LASIR, PhLAM and UMS ICARE, which are also backed by IRePSE. However, particular attention will be paid to emerging projects outside CaPPA in order to ensure that the projects are complementary (especially for the "health impacts" theme which is currently not covered by the Labex CaPPA project).
The aim will be to better identify the effects (direct or indirect) of aerosols on the climate, their sources and their future. In addition, since these can come from secondary sources after oxidation of the gas phase, for example, and undergo transformations during their transport, it is necessary to better characterize the transformations of the gaseous species which are sources of aerosols as well than the physical and chemical properties of the different types of aerosols (organic, inorganic, aged, etc.) in order to precisely estimate their impact. Thanks to advances made in the framework of the Labex CaPPA, atmospheric observation methods at different spatial scales (from the meso-scale to the global scale) are developed and make it possible to map the main pollutants from the continental level to the regional level. . These long-term observations are enriched with results from field campaigns in which instruments are deployed allowing advanced characterization of pollutants with particular attention to aerosol particles (size and chemical composition). These data feed into atmospheric inversion models or direct models which aim to trace the origin of the emission of these pollutants (natural or anthropogenic, local emission or distant inputs) and to differentiate peak events from particulate pollution.
By relying on the know-how of the regional teams in atmospheric physico-chemistry, and in particular on their expertise in in situ sampling techniques and physico-chemical analyzes, it is now possible to characterize and monitor very air pollutants and their properties, whether in gaseous or particulate form. Thanks to the reinforcement of the IMPECS laboratory teams, the institute will encourage the emergence of projects combining atmospheric sciences and health impacts. Indeed, it is now recognized that air pollution has dramatic effects on human health, in particular on the respiratory level, and undeniably constitutes a major problem for the international community. The World Health Organization (WHO) has estimated that in 2012, ambient air pollution was responsible for nearly 7 million deaths worldwide, or more than 10% of deaths from all causes, and could be considered the greatest environmental health risk (WHO, 2014, http://who.int.gate2.inist.fr/phe/health_topics/outdoorair/databases/en/).
With the emergence of individual pollutant sensors on the market, it is possible to monitor the exposure of populations to the main regulated pollutants at the individual level. However, we are only at the beginning of these developments and these sensors must be more finely tested, calibrated and calibrated with certified techniques in order to rigorously exploit the measurements resulting from these miniaturized technologies. Finally, studies on the phytosanitary impacts of pollutants, such as ozone or particles, could also be considered.
Four axes are envisaged for this scientific field:
- Axis 1 concerns "air pollutants and impacts on plants and human health". The theme "air pollutants" is in line with the study of transformations from the gas phase to the particulate phase of the CaPPA labex (WP1 focused on biogenic species) and is complementary because it aims to quantify pollutants in the atmosphere and to study their transformations. It will be in this area to provide a sanitary and phytosanitary component to broaden this theme to impacts on populations and ecosystems.
- Axis 2 “aerosols and health impacts” is complementary to the WP2, 3 and 4 of the CaPPA labex centered respectively on (i) the physical, chemical and optical properties of aerosols for their remote sensing, (ii) the observation of aerosols at different scales, and (iii) the determination of sources using satellite data. Axis 2 of IRePSE aims to extend these themes towards a better characterization of the composition of aerosols and their sanitary and phytosanitary impacts. This will include studying the role of the fine and ultrafine fraction of aerosols on respiratory diseases (COPD, asthma, lung cancer) depending on the nature of the particles (source, chemical composition, bioavailability). The toxicity effects of these particles can be evaluated using animal models but also in vitro on primary cultures of pulmonary epithelial cells.
- Axis 3 "clouds and water cycle" is similar to LabexCaPPA WP5, which focuses on the study of the indirect effects of aerosols and their role in the life cycle of clouds. The IRePSE project aims to provide information on the role of aerosols in (i) the formation of cloud droplets, (ii) the quantification of the transfer of gaseous and particulate pollutants to the droplets, and (iii) their elimination from the atmosphere. through precipitation. The IRePSE project also aims to continue and improve the characterization of atmospheric water (water vapor and cloud), at different spatial scales (from regional to planetary), since it plays an important role in the climate current and its future evolution.
- Axis 4 "Remediation" relates to the use of new fuels (biofuels, addition of hydrogen) to reduce pollutants at source and greenhouse gases. The innovative techniques for characterizing NOx, soot and their precursors (HAPs) recently developed will be used to characterize the impact of different families of fuels on the production of these species.