London, Sept. 29 (Reuters): Sunscreen creams cannot fully protect people against an increasingly common form of skin cancer even when correct amounts are applied, according to research published today.
The study by scientists at a British medical charity found that the creams fail to stop harmful rays of the sun from penetrating the skin.
Professor Roy Sanders, a consultant plastic surgeon with the Restoration of Appearance and Function Trust (RAFT), said suncreams were much less effective at blocking ultraviolet A (UVA) light, which can cause the skin cancer melanoma, than UVB. “When ultraviolet A impinges on the skin it triggers the release of highly reactive chemicals called free radicals which we believe can induce a malignant change,” he told BBC Radio.
“Since ambient sunlight is principally ultraviolet A and since sunscreens protect mostly against ultraviolet B, if we use the sunscreens it may increase the risk of us developing a rather unpleasant cancer called malignant melanoma,” he said.
Cases of malignant melanoma have doubled every 10 years since the 1950s and the cancer now kills around 1,500 people in Britain every year.
Sanders and colleagues at RAFT exposed skin samples removed from consenting patients during surgery to UVA light at intensities similar to that of sunlight. The skin had been treated with three popular high factor suncreams which say they contain some UVA protection. While the creams prevented the sun from burning the skin, they did not stop UVA rays from penetrating it, RAFT said.
Sanders said the concern was that people were using the creams believing that they offered protection against cancer and, comforted by that, might be putting themselves at risk.