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