A non-polluted air environment is crucial during the early years of life to ensure proper lung development and reduce the risk of chronic respiratory diseases. In particular, the first six years of life is a critical window for lung development. Exposure to clean air promotes the optimal growth of the airway and lung tissue during this time, and the trajectory for the rest of life is determined at the same time. In other words, if airway and lung growth is sub-optimal in the first six years, it will be very difficult to change the lung function trajectory for the rest of life.
