2019 Yes https://www.resmedjournal.com/article/S0954-6111(19)30016-2/fulltext Sasso, Fabien Europe Review Students Elementary (K-5) Carbon Dioxide (CO2) Carbon Monoxide (CO) Volatile Organic Compounds (VOCs) Nitrogen Dioxide (NO2) Respiratory symptoms Asthma Allergy prevalence Epidemiology Air pollution Children Overall, the prevalence of asthma and of allergic diseases exhibited an increasing trend in the time interval between the two studies, significant only for dry cough and pollen allergy. The level of air pollutants decreased significantly indoors. In spite of this, we found a correlation and a dose-effect relationship between the level of PM2.5 and the prevalence of asthma. A family history of asthma and allergies, the insalubrity of the place of residence, and a non-Mediterranean diet were also associated with the risk of these diseases.