Sun cream cancer concern

Shielding your skin from sunburn provides little protection from cancer, according to new research.

UVB (ultraviolet B) rays, which cause burning, have relatively little effect on skin DNA, scientists have discovered.

It is UVA rays, which cause ageing effects, that are more likely to cause tumours to develop.

In the past, the ageing rays were considered less of a cancer risk because they are less easily absorbed.

But researchers at the University of Sydney have discovered that they actually penetrate deeper. Rather than simply causing superficial skin damage, they may be responsible for more serious internal mutation.

Prof Gary Halliday said: 'The importance of protecting the population not just from UVB but also from UVA irradiation has profound implications on public health.'

Most sunscreens in this country protect against both rays. But Prof Halliday said the wide use of creams in Australia which simply offered

protection against sunburn may have increased the cancer risk. His team examined tissue samples of tumours in 16 patients treated for skin cancer.

Most of the UVB damage was in the outer skin layers. But underlying cells in which cancer developed displayed UVA damage.

'The UVA mutations reinforce the pivotal role it may play in the malignant transformation of skin,' Prof Halliday told journal Proceedings of the National Academy of Sciences.

'This has profound implications on public health worldwide.'