Amazouz H, Bougas N, Thibaudon M, et al. - Since daily levels of ambient air pollution and pollen may influence lung function but have rarely been tested together, researchers sought to examine short-term exposure to pollen and air pollution in relation to lung function in school-age children from a French population-based birth cohort. Participants in the study were 1,063 children from the PARIS (Pollution and Asthma Risk: an Infant Study) cohort whose lung function and FeNO measurements were performed at age 8 years old. Four clusters of exposure have been identified: no pollen and low air pollution (Cluster 1), grass pollen (Cluster 2), PM ₁₀ (Cluster 3) and birch/plane-tree pollen with high total pollen count (Cluster 4). Findings suggested that daily ambient chemical and biological air quality could adversely affect lung function in children.