Exposure to traffic and greenspace, and associations with respiratory health in urban India

Asthma and related respiratory symptoms are growing in India and urban cities are experiencing increasing traffic-related air pollution (TRAP) levels. Our study investigates the association between TRAP and respiratory symptoms, and unplanned visits made to general practitioner/emergency department/hospital admission in children and adolescents; we also aimed to understand whether low greenspaces surrounding the schools impacted this association. Trucks passing near the child's residences were used as a surrogate marker for measuring exposure to heavy TRAP. Exposures to school neighbourhood characteristics such as distance from major roads, a major source of TRAP, and industries were studied and the Normalized Difference Vegetation Index (NDVI) was used to measure greenspaces at 100 m and 200 m. Results showed no relationship between TRAP exposures and the odds of unplanned visits to general practitioners/emergency department /hospital admissions in young children; however, adolescents experienced increased risk. TRAP-related characteristics and greenspaces (within 200 m) strongly interacted with childhood respiratory symptoms. Our findings suggest exposure to TRAP near residences is increasingly harmful, and the school neighbourhood factors contribute to the risk of respiratory symptoms in children and adolescents in urban areas. Further studies in different regions are needed to verify our findings based on the causal mechanisms. •Traffic-related air pollutants in low to moderate-pollution cities affect children.•Respiratory health of children is related to school distance to air pollutant sources.•Traffic-related air pollutant contribute to increased emergency departmental visits.•Urban school neighbourhood factors linked to increased respiratory symptoms.•Asthma-related respiratory symptoms in children vary in low and moderate greenspaces.