From:  An expert position paper on environment, occupation and climate change effects on allergic respiratory diseases in Italy

 Effects of outdoor air pollution on the respiratory health of children and adolescents.

StudyPopulation/AreaOutdoor exposureOutcomesEffect estimation
Squillacioti et al., 2019 [62]187 children (7–11 years)NDVI; urban exposure to NO2 (average 55.6 μg/m3)Asthma, bronchitis, wheezing; respiratory functionHigher NDVI associated with lower risk of asthma (OR 0.13), bronchitis (OR 0.14) and wheezing (OR 0.25). Reduction of forced expiratory flow between 25 and 75% of forced vital capacity (FEF25–75) in children less exposed to greenness
Zammit et al., 2020 [66]Primary school children, Sicily (n = 1,190) and Malta (n = 1,210)PM2.5 and elemental composition (V, Pb, Ni, Zn)Asthma, rhinitis, medication use↑ PM2.5 associated with ↑ risk of asthma (OR ≈ 1.04); V and Pb more associated with respiratory outcomes
Bonato et al., 2021 [67]98 children (5.3 ± 2.9 years) with and without wheezingPM10, NO2, SO2 (preceding 90 days)Bronchial remodeling, inflammationPM10 associated with basal membrane thickening and ↑ eosinophils; greater effect in children with wheezing
Bonato et al., 2021 [68]34 preschool childrenPM10, NO2, SO2 (acute exposure)Epithelial antiviral responseNO2 associated with ↓ IFN-β and ↑ Rhinovirus replication
Di Cicco et al., 2022 [63]85 children (0–17 years) hospitalizedTotal pollens; spores of Alternaria alternataAsthma/asthma-like hospitalizations (indicators of respiratory exacerbation)Increments of 10 granules/m3 associated with ↑ risk of hospitalization: Lag 0 OR 1.054; Lag 1 OR 1.037; Lag 2 OR 1.021. More marked effects in sensitized, males, and > 10 years
Cilluffo et al., 2022 [60]179 asthmatic childrenUrban greenness (NDVI), traffic, NO2Asthma control↓ Urban green areas associated with uncontrolled asthma (OR ≈ 2.66); no association with NO2 or traffic
Panunzi et al., 2023 [65]7,525 subjects (0–21 years; ~6,800 < 18 years)PM10, PM2.5, NO2 (ELAPSE/EPISAT models), distance from plantsAllergological, ENT, pneumological visits; hospitalizations and respiratory ED accessesPM10 associated with ↑ allergy visits (RR 1.32; 95% CI 1.14–1.52). J-curve with higher rates < 2 km and > 20 km from the industrial plants. NO2 not significant
Sarno et al., 2024 [64]2,367 children (6–14 years)Residence near crops treated with pesticidesUpper airway, ocular, skin, systemic symptomsUpper airway (rhinitis/nasal symptoms): OR 2.25. Ocular symptoms: OR 3.81. Skin: OR 2.60
Cilluffo et al., 2018 [59]219 children (8–10 years)NDVI, “greyness”, distance from traffic (≤ 200 m), NO2Nasal, ocular, respiratory symptomsLow NDVI associated with ↑ rhinitis (OR 1.47, 95% CI 1.07–2.03). Residence ≤ 200 m from traffic associated with ↑ rhinitis (OR 1.49, 95% CI 1.12–1.98). NO2 not significant

Lag: time interval in days between peak exposure to pollutant and health event. CI: confidence interval; ED: emergency department; ENT: ear, nose and throat; NDVI: normalized difference vegetation index; NO2: nitrogen dioxide; OR: odds ratio; PM2.5: atmospheric particulate matter with a diameter ≤ 2.5 μm; PM10: atmospheric particulate matter with a diameter ≤ 10 μm; RR: relative risk; SO2: sulphur dioxide.