It's all just talk

Are there different types of air pollution?

Yes. The most damaging but best understood are tiny particles. These not only damage the lungs, but enter the bloodstream. They are increasingly thought to enter vital organs, including the brain and have been shown the reach the liver, spleen, kidneys and testes in lab animals.

Masks are now commonly advertised, but experts say they are of limited use unless they have an airtight seal on the face, which is rare.