Skin cancer is one of the most rapidly increasing forms of cancer in England and Wales, with more than 5,700 new cases each year.

Scientists blame an increase in foreign summer holidays, combined with poor use of sunscreen, for the enormous rise.

Research has shown exactly how failure to apply sun screen properly can cause skin cancer.

Figures from the Institute of Cancer Research (ICR) show that malignant melanoma rates, the most deadly form of skin cancer, for men have gone up more than three times since 1971 and in women the rates have more than doubled.

Survival rates are getting better for skin cancer.

But because so many people are getting the disease the death rates have risen from 793 in 1979 to 1,476 in 1999 - an increase of 86%.

These findings should convince the most determined sun-worshipper that it's just not worth the risk Brad Timms, of the CRC

Professor Anthony Swerdlow, of the ICR, blamed the problem on holiday makers taking more jaunts abroad and wearing increasingly skimpy clothes.

He said: "In both men and women, the percentage rise has been the greatest for melanoma of the trunk and upper limb.

Over exposure to the sun can cause irreperable damage

"Men were the first to expose their trunks extensively on the beach, followed later by the fashion for bikinis in women. The melanoma statistics appear to reflect this.

"Another example is melanoma of the ear, of which there are more cases in men than women, presumably because if you wear long hair, your ears are protected."

The scientists said that office workers were particularly at risk, because their skin sees little sun during the week.

With the start of Sun Awareness Week Brad Timms, scientific information officer at the Cancer Research Campaign (CRC) said: "These findings should convince the most determined sun-worshipper that it's just not worth the risk.

"Sunshine rates in this country have not been getting better. It's the change in lifestyle and fashion that has led to this alarming rise in cases of malignant melanoma."

Skin care

Try not to burn skin Take special care of babies and children's skin Avoid the sun in the middle of the day Avoid sunbeds and sun lamps Cover up in loose fitting clothes made from tightly woven fabric and wear a hat

Dr Mark Birch-Machin, a research lecturer in molecular dermatology at Newcastle University, said many people were applying their sunscreen too thinly , meaning they only get a fraction of the protection they could.

"Manufacturers rely on sunbathers applying the correct thickness of sunscreen to get the recommended protection from the UltraViolet (UV) rays. But people apply sun-cream sparingly which is a false econonmy considering the risk of long-term damage to their skin DNA."

Dr Birch-Machin said the skin damage is cumulative and can date back to childhood. He said there was a link between exposure to sunlight and damage to the DNA that is found in mitochondria, which is the powerhouse of the cell.

Malignant melanoma is the most deadly form of skin cancer

He said that compared to the DNA found in the nucleus of cells, the sun-damaged DNA in mitochondria is hardly ever repaired and so damages pile up.

"It's almost like a diary of sun-damaged DNA."

Using the correct amounts of sun screen he said could prevent the UV rays reaching the skin.