How does pulmonary elimination work?

Apart from specific cases, deposited particles are eliminated from the lungs by natural clearance mechanisms:

• physical: insoluble particles deposed in the trachea-bronchial tree and the upper airways are in majority eliminated by Muco-ciliary transport towards the noise and the mouth. They are swallow or release toward outside (sneeze,…). At the level of pulmonary alveoli, macrophages take charge of the elimination of insoluble particles by phagocytosis,
• chemicals: dissolving (for those that are soluble) or fixing to the components of the liquid lining the airways permit their transfer in the blood and excretion in the urine. The chemical elimination processes occur in all regions of the respiratory system.