Évaluer les expositions aux contaminants de l'air intérieur et les paramètres de confort et leur impact sur la santé des enfants vivant en milieu urbain

Contexte : Les effets de l'exposition à la pollution sur la santé allergique et respiratoire et sur la cognition des enfants ont suscité une inquiétude croissante au cours des dernières décennies. Plusieurs études environnementales et épidémiologiques ont été menées au fil du temps, mais les résultats sont contradictoires et les données concernant l'environnement intérieur sont encore très rares. L'objectif principal de cette thèse est de contribuer au débat sur l’impact de l’environnement scolaire sur la santé des écoliers en mesurant de façon objective et standardisée certaines caractéristiques de l'environnement intérieur des écoles primaires en Europe afin de comprendre son impact sur la santé des écoliers en ciblant en particulier les symptômes allergiques et respiratoires. Méthodes et matériel : Une étude transversale (SINPHONIE) a été menée de 2010 à 2012 dans le cadre des projets menés par la DG SANCO de la Commission Européenne. Dans ce travail de thèse, à partir de données de l’étude SINPHONIE nous avons investigué l'association entre les polluants de l'air intérieur, l'agent microbiologique (endotoxine) en classe et la santé chez 5175 écoliers européens, en utilisant les données provenant de 115 écoles dans 54 villes européennes de 23 pays, recueillies et incluses par le biais d’un protocole harmonisé et standardisé. Les informations sur la santé de l'enfant ont été obtenues à l'aide d'un questionnaire auto-administré rempli par les parents, basé sur les questionnaires ISAAC (International Study of Asthma and Allergies in Childhood), HESE (Health Effects of School Environment) et l'étude SEARCH (School Environment and Respiratory Health of Children) ; pour les propos de cette thèse seulement les symptômes et maladies s’étant manifestés récemment, notamment dans les trois derniers mois, ont été considérés. En guise de complément, la spirométrie et les tests de fractionnement de l'oxyde nitrique expiré (FeNO) ont été effectués à l'école par des professionnels de la santé formés pour l’enquête. En termes d’exposition, les mesures des concentrations des composés organiques volatils (COV), du formaldéhyde, du monoxyde de carbone, des particules fines (PM2,5), du dioxyde de carbone (CO2), du radon, de la température, de l'humidité relative et des biocontaminants dont les endotoxines ont été effectuées à l'intérieur des classes selon un protocole standardisé. Des modèles statistiques de logistique, de régression linéaire et de méta-analyse ont été appliqués pour étudier l'association entre les polluants chimiques, les endotoxines et les paramètres de confort en classe et son effet allergique, la santé respiratoire et les performances scolaires, tout en ajustant plusieurs facteurs de confusion. Prendre en compte le phénomène multi-polluant de l'air intérieur ; un score de COV, défini comme la somme du nombre de polluants auxquels les enfants étaient fortement exposés (concentration supérieure à la médiane de la distribution) dans la classe a également été introduite. Le même ensemble de données de santé a été utilisé pour étudier l'association entre la lumière du jour dans les salles de classe et les performances scolaires, qui a été peu investigué. Dans ce cas, les données étaient disponibles pour 2670 écoliers âgés de 8 à 13 ans et provenaient de 155 salles de classe dans 53 écoles réparties dans 12 pays européens. Les données sur l’illumination ont été acquises par le biais d'évaluations physiques directes et de questionnaires remplis par les enseignants, les écoliers et leurs parents, permettant d'estimer de multiples indicateurs objectifs de la lumière du jour, ainsi que des paramètres subjectifs tels que la perception de l'éclairage. Les écoliers ont effectué un test d'attention/concentration comprenant des exercices mathématiques simples ainsi qu'un test de chiffrage logique. Les scores de performance correspondants ont été comparés à de multiples paramètres d'éclairage naturel. [...]Background : The effects of exposure to pollution on allergic and respiratory health and cognition among children have been of growing concern over recent decades. Several environmental and epidemiological studies have been carried out over time, but the results are conflicting and data concerning indoor environment is still very scarce. The main objective of this thesis is to contribute to the debate on the impact of the school environment on the health of schoolchildren by objectively and standardized measurement of certain indoor environmental characteristics in primary schools in Europe in order to understand its impact on health by targeting, in particular allergic and respiratory symptoms. Methods and Material : A cross sectional study (SINPHONIE) was conducted from 2010 – 2012 as part of the projects led by DG SANCO of the European Commission. In this thesis work, using the SINPHONIE dataset, we investigated the association between indoor air pollutants, microbiological agent (endotoxin) in the classroom and health in 5,175 European schoolchildren, using data from 115 schools in 54 European cities from 23 countries, collected and included through a harmonized and standardized protocol. The child health information was obtained using a self-administered questionnaire completed by the parents, based on the ISAAC (International Study of Asthma and Allergies in Childhood), HESE (Health Effects of School Environment) and the SEARCH study (School Environment and Respiratory Health of Children) questionnaire; for the purpose of this thesis only recent symptoms i.e. during the past three months were considered.. As a compliment, spirometry, and fractional exhaled nitric oxide (FeNO) tests were performed at school by trained health professionals trained for the survey. In terms of exposure, measurements of the concentration of volatile organic compounds (VOC), formaldehyde, carbon monoxide, particulate matter (PM2.5), carbon dioxide (CO2), temperature, relative humidity, and biocontaminants (endotoxin) were obtained from classrooms according to the standardized protocol. Logistic, linear regression and meta-analysis techniques were applied to study the association between chemical pollutants, endotoxin and classroom comfort parameters and its effect allergic, and respiratory health and school performance, while adjusting for several confounding factors. To take into the multi indoor air pollutant phenomenon; a VOC score, defined as a sum of the number of pollutants to which children were highly exposed (concentration greater than median of the distribution) in the classroom was also introduced. To study the association between daylight in classrooms and school performance, same health dataset was used. In this case, the data was available for 2670 schoolchildren, aged 8 – 13 and came from 155 classrooms in 53 schools across 12 European countries. Data on illumination were acquired through direct physical assessments and questionnaires completed by teachers, schoolchildren, and their parents, allowing for estimations of multiple objective daylight indicators, as well as subjective parameters such as the perception of lighting. Schoolchildren performed an attention/concentration exam that included simple mathematical exercises in addition to a logical ciphering test. The corresponding performance scores were compared against multiple daylighting parameters. [...

Daylight and School Performance in European Schoolchildren

International audience: Aims and objectives: Lighting constitutes a critical issue in school design because of its importance as a strong enabler of performance, which is crucial for child development. However, data on light impacts on school performance are scarce. The main objective of this study was to assess the relationship between daylighting conditions in classrooms and mathematical and logical test scores.Methods: The population-based SINPHONIE (Schools Indoor Pollution and Heath: Observatory Network in Europe) study provides information on relationships between lighting conditions and school performance for 2670 elementary schoolchildren, aged 8-13 years from 155 classrooms in 53 schools across 12 European countries. These data were acquired through direct physical assessments and questionnaires completed by teachers, schoolchildren, and their parents, allowing for estimations of multiple objective daylight indicators, as well as subjective parameters such as the perception of lighting. Schoolchildren performed an attention/concentration exam that included simple mathematical exercises in addition to a logical ciphering test. The corresponding performance scores were compared against multiple daylighting parameters.Results: A positive relationship was found between performance scores and type of window shading, latitude, percentage of window facing south, and window glazing, with the highest impact due to the window-to-floor area ratio.Conclusion: Data collected in the SINPHONIE study across 12 European countries indicate that daylighting parameters are relevant to schoolchildren's performance. As SINPHONIE was not designed specifically with lighting in mind, dedicated studies covering a wide range of classroom configurations would be enlightening

Indoor air pollution, physical and comfort parameters related to schoolchildren's health: Data from the European SINPHONIE study

Substantial knowledge is available on the association of the indoor school environment and its effect among schoolchildren. In the same context, the SINPHONIE (School indoor pollution and health: Observatory network in Europe) conducted a study to collect data and determine the distribution of several indoor air pollutants (IAPs), physical and thermal parameters and their association with eye, skin, upper-, lower respiratory and systemic disorder symptoms during the previous three months. Finally, data from 115 schools in 54 European cities from 23 countries were collected and included 5175 schoolchildren using a harmonized and standardized protocol. The association between exposures and the health outcomes were examined using logistic regression models on the environmental stressors assessed in classroom while adjusting for several confounding factors; a VOC (volatile organic compound) score defined as the sum of the number of pollutants to which the children were highly exposed (concentration > median of the distribution) in classroom was also introduced to evaluate the mul tiexposu re - outcome association. Schoolchildren while adjusting for several confounding factors. Schoolchildren exposed to above or equal median concentration of PM2.5, benzene, limonene, ozone and radon were at significantly higher odds of suffering from upper, lower airways, eye and systemic disorders. Increased odds were also observed for any symptom (sick school syndrome) among schoolchildren exposed to concentrations of limonene and ozone above median values. Furthermore, the risks for upper and lower airways and systemic disorders significantly increased with the VOCs score. Results also showed that increased ventilation rate was significantly associated with decreased odds of suffering from eye and skin disorders whereas similar association was observed between temperature and upper airways symptoms. The present study provides evidence that exposure to IAPs in schools is associated with various health problems in children. Further investigations are needed to confirm our findings

Indoor air pollution, physical and comfort parameters related to schoolchildren's health:Data from the European SINPHONIE study

Substantial knowledge is available on the association of the indoor school environment and its effect among schoolchildren. In the same context, the SINPHONIE (School indoor pollution and health: Observatory network in Europe) conducted a study to collect data and determine the distribution of several indoor air pollutants (IAPs), physical and thermal parameters and their association with eye, skin, upper-, lower respiratory and systemic disorder symptoms during the previous three months. Finally, data from 115 schools in 54 European cities from 23 countries was collected and included 5175 schoolchildren using a harmonized and standardized protocol. The association between exposures and the health outcomes were examined using logistic regression models on individual indoor air pollutants (IAPs); a VOC (volatile organic compound) score defined as the sum of the number of pollutants to which the children were highly exposed (concentration > median of the distribution) in classroom was also introduced to evaluate the multiexposure \u2013 outcome association, while adjusting for several confounding factors. Schoolchildren exposed to above or equal median concentration of PM2.5, benzene, limonene, ozone and radon were at significantly higher odds of suffering from upper, lower airways, eye and systemic disorders. Increased odds were also observed for any symptom (sick school syndrome) among schoolchildren exposed to concentrations of limonene and ozone above median values. Furthermore, the risks for upper and lower airways and systemic disorders significantly increased with the VOCs score. Results also showed that increased ventilation rate was significantly associated with decreased odds of suffering from eye, skin disorders whereas similar association was observed between temperature and upper airways symptoms. The present study provides evidence that exposure to IAPs in schools is associated with allergic and respiratory symptoms in children. Further investigations are needed to confirm our findings