What We Do
Although the link between indoor environmental quality and the health and well-being of occupants is no longer disputed, there is still less information available on this topic than on outdoor air. However, due to modern lifestyles, the majority of the general population spends about 80% of their time in increasingly confined indoor environments (home, work, school, or public transportation). This has health implications due to the variety of pollution sources, which can sometimes be numerous.
To best protect the public, Santé publique France’s missions aim to gather robust data to objectively assess the health impact of these environments, thereby guiding public health initiatives and promoting environments conducive to good health.
Assessment of the Health Impact of Indoor Environment Quality
For several years, Santé publique France has coordinated national surveillance of childhood lead poisoning and contributed to the investigation of unexplained mass illness events. However, the health impact of indoor environments is still largely overlooked in actions taken at both the local and national levels. Santé publique France has therefore sought to strengthen its activities on the link between indoor environmental quality and health by:
conducting studies to gain knowledge about the impact of indoor environmental quality on public health, particularly among the most vulnerable populations;
conducting quantitative health impact assessments (EQIS).
Initial research was conducted on the link between housing and health and was subsequently expanded to other environments, such as school settings. The goal of these initiatives is to provide useful knowledge to support public policies aimed at improving living conditions for the population and preventing health risks associated with environmental or occupational exposures. Although this work is currently focused primarily on indoor air quality, the goal is eventually to consider all factors related to indoor environments (thermal comfort, noise, etc.). Particular attention is also given to issues of energy poverty and the impact of climate change, along with the resulting adaptation and mitigation measures.
As part of its mandate, Santé publique France sought to expand knowledge regarding the health effects of indoor air pollution on residents. To this end, a collaboration with the Indoor Air Quality Observatory was established as part of the National Housing Campaign 2 (CNL2). This study, launched in 2020, aims to assess the current state of indoor air quality in housing in metropolitan France and track its evolution since the first campaign conducted in 2003–2005. It is part of the 4th National Health and Environment Plan (Action 14.1 titled “Gaining a Better Understanding of Indoor Air Quality in French Homes”).
CNL2 is based on environmental measurements combined with questionnaires administered to a projected sample of approximately 600 homes representative of the housing stock in metropolitan France. Santé publique France is responsible for managing the “health/perception” component. This component will collect data on the health of study participants, thereby enabling an examination of the link between the population’s health status and pollution levels found in homes. It will also describe their knowledge, practices, and perception of risk regarding indoor air quality.
Other studies have also been conducted on the interactions between substandard housing and residents’ health.
Santé Publique France is implementing quantitative health impact assessments (EQIS) that document the impact of outdoor air pollution on morbidity and mortality in France and its regions. This assessment also quantifies the expected benefits of improved air quality. These approaches raise awareness among public authorities and the general public about the consequences of poor outdoor air quality.
Schools are the second most frequent indoor environment for children, after the home
Implementing such an approach to indoor environmental pollution could improve understanding of the health impacts of indoor air quality and serve as a powerful tool to convince various stakeholders of the importance of promoting healthy indoor environments. Work has therefore been initiated to apply the EQIS approach to indoor air pollution issues, notably by studying the relevance and feasibility of this approach in school settings through initial EQIS assessments. Indeed, schools and daycare centers have been identified as priority areas to consider due to the amount of time children spend in these environments and the sensitivity of the child population to the impact of pollution.
In this context, a study on the relevance and feasibility of EQIS-PA in school settings was conducted. Four priority areas were identified:
the impact on childhood asthma:
formaldehyde from indoor sources,
nitrogen dioxide (NO₂) associated with proximity to road traffic near schools,
humidity and mold;
the impact of poor air exchange on children’s learning. Following this study, an initial EQIS was implemented at the national level to assess the impact of improved classroom air quality—primarily regarding formaldehyde and mold—on the prevalence of childhood asthma.
Learn more: Quantitative Health Impact Assessment (QHIA) of air quality in and around schools
In a second phase, HIA studies tailored to specific regions will be implemented to supplement these initial findings. The aim will be to confirm the estimates obtained for formaldehyde using more detailed environmental and health data and to apply the methodology to the NO2-asthma relationship. The objective is to assess the health benefits of measures to reduce air pollution from road traffic near schools in urban areas.
Additionally, a literature review on the link between carbon dioxide (CO2) and children’s learning was conducted to identify potential avenues for further research on the subject, particularly the implementation of initial EQIS studies given the relevance of currently available data.
Learn more: Link between CO2 concentrations in classrooms and children’s learning
Measures to prevent health risks associated with indoor air pollutants
Prevention of health risks associated with indoor air pollutants is integrated into the population-based prevention approach. Since the first 1,000 days are a period of high vulnerability to exposure to certain pollutants, priority has been given to this population. Advice and practical solutions to reduce exposure are available on the Santé publique France website at les 1000-premiers-jours.fr. These messages also apply to the rest of the population.
See also individual actions and collective measures to improve indoor air quality.
