"Oxidative Damage" occurs when skin is exposed to sunlight and UV radiation is absorbed by skin molecules that generate harmful compounds. These reactive oxygen species are known as ROS and are highly reactive.
An example is when ROS react with cellular parts like cell walls, lipid membranes, mitochondria and DNA. This leads to skin damage and increased signs of aging.
Hanson, who works in the laboratory of Christopher Bardeen, an assistant professor of chemistry at UCR, said, "Sunscreens do an excellent job protecting against sunburn when used correctly. This means using a sunscreen with a high sun protection factor and applying it uniformly on the skin."
However, over time, special molecules called UV filters applied on the skin penetrate into the skin below the surface of the epidermis (the outermost layer of the skin); this leaves the body open to UV radiation.
He added, "Our data show, however, that if coverage at the skin surface is low, the UV filters in sunscreens that have penetrated into the epidermis can potentially do more harm than good".
Hansen told Asia News International, "More advanced sunscreens that ensure that the UV-filters stay on the skin surface are needed; such filters would reduce the level of UV-induced ROS. Another solution may be to mix the UV-filters with antioxidants since antioxidants have been shown to reduce UV-induced ROS levels in the skin."The researchers recommend it is best to use sunscreen often and then re-apply it every two hours as the Skin Cancer Foundations suggests.
