Scientists looked at 41 studies about dirty air and eye health. The studies included millions of people in East Asia and the United Kingdom. People around more tiny pieces of dirt in the air had a higher risk of two eye diseases.
One disease, glaucoma, harms the nerve that sends information from the eye to the brain. It can cause people to lose their sight forever. The other disease, cataracts, makes the eye's lens cloudy. People then see less clearly. Getting older also raises the risk of both diseases.
The clearest link involved the smallest pieces in the air. But these studies do not prove that dirty air causes the diseases.
