Current test for sunglasses effectiveness needs revamping, researcher claims.
Brazilian researchers say sunglasses' UV protection diminishes over time, and that they should be replaced every two years, the Daily Mail reports. According to the article, Professor Liliane Ventura of Sao Paulo University says UV light's effects on the eye are especially pronounced in tropical countries, where UV indexes are high in the summer, and that a better test is needed for determining whether sunglasses are safe. Prolonged exposure to UV can result in edema, cataracts and damage to the macula. The results of the study were published in the journal Biomedical Engineering Online.