2019 Yes https://www.sciencedirect.com/science/article/pii/S016041201832186X Oliverira, M North America Europe Asia Australia South America Africa Review Students Elementary (K-5) Middle/Jr High (6-8) Particulate Matter (PM) Biomarkers Children exposure Health effects Particulate matter (PM) Polycyclic aromatic hydrocarbons (PAHS) Strong evidences demonstrated associations between environmental exposure to PM and PAHs with several health outcomes, including increased risk of asthma, pulmonary infections, skin diseases, and allergies. Nevertheless, there is a scientific gap on studies that include the characterization of PM fine fraction and the levels of PAHs in the total air (particulate and gas phases) of indoor and outdoor air of school environments and the associated risks for the health of children. There is a clear need to improve indoor air quality in schools and to establish international guidelines for exposure limits in these environments.