Damage to skin cells continues for hours after spending time in the sun, according to research that uncovers a new link between sun exposure and cancer. The discovery that some of the most serious damage to skin cells may be occurring in the dark raises the prospect of new “evening after” lotions that would help limit the effect and reduce the risk of skin cancer.
The source of the “dark damage” was found to be melanin, the pigment in skin cells that normally acts as a shield against ultra-violet (UV) radiation.
The latest research at Yale University led by Prof. Douglas Brash reveals that UV light produces a cascade of chemical reactions that reacts with melanin causing one of its electrons to be “excited”. The melanin then deposits its extra energy in the surrounding tissue.
If a strand of DNA happens to be nearby, it can absorb the energy causing the double helix strand to bend and scramble the letters of the genetic code into mutations.
The more mutations skin cells accumulate over time, the higher the likelihood that one of them will turn out to be cancerous. — © Guardian Newspapers Limited, 2015
