• Increased susceptibility to infection from impaired immune defences

• Airways inflammation leading to impaired gas exchange and hypoxia (deficiency of oxygen reaching the tissues of the body)

• Provocation of alveolar inflammation* by ultrafine particles with the release of mediators that exacerbate underlying lung diseases and increase blood coagulability

• Increased lung permeability leading to pulmonary edema (excessive accumulation of fluid on the lung tissues)

• Precipitation of heart failure in those with chronic heart disease by acute bronchiolitis** or pneumonia induced by pollution

Source: Particles in our air: Health effects and concentrations, edited by Richard Wilson and John Spengler, Harvard University Press, USA
* alveolar inflammation