The heat is on for sunworshippers

Mar 24 2008 Western Mail

THE 11 warmest years on record have all occurred in the past 13 years, and already in February temperatures have hit the headlines, writes Harryono Judodihardjo.

Ceredigion clocked up the highest temperature of all last month which, at 18C, was more than double the February average of 7C.

So what implications does this have for skin cancer? And how can we protect ourselves and still lead a normal life?

Global temperatures are on the rise, and the trend looks set to continue in 2008, as worldwide temperatures are predicted to be 0.37C above the long-term average.

And, as the UK climate become hotter and brighter, the population becomes increasingly at risk from skin cancer.

I believe that well-orchestrated public education campaigns play a powerful role in changing public perceptions.

Australia’s well-documented Slip! Slop! Slap! awareness campaign, for example, helped to shift attitudes towards sun safety. Although Australia still has one of the highest rates of skin cancer in the world, the number of young people going outside for the purpose of getting a tan has dropped significantly in recent years.

Australia’s high rate of skin cancer is exacerbated by the depletion of the ozone layer, and the fact that a largely light-skinned population lives in a tropical latitude.

As climate change kicks in, we could face similar problems here.

Fair-skinned Welsh people do not have natural pigmentation in the skin, which is designed to deflect the damaging effects of fierce sunlight.

The three most common forms of skin cancer are squamous cell carcinoma, basal cell carcinoma and melanoma.

Squamous cell carcinoma relates to long-term exposure to sunshine – the damage accumulated over a protracted period results in cancer on exposed areas such as the face, neck and backs of hands.

Basal cell carcinoma is the most common of the three types of skin cancer. It is also associated with accumulated exposure, but bears a closer correlation to the number of sunburn episodes over the course of a lifetime, particularly childhood sunburn.

Melanoma is the least common, but most deadly, form of skin cancer. It grows very aggressively and metastasises rapidly. Melanoma is strongly related to severe sunburn, particularly during childhood.

The number of melanoma cases worldwide is increasing faster than any other cancer, and in the UK the incidence of melanoma has risen by 40% in the past decade.

Exposure to UV radiation in sunlight is the main cause of skin cancer. Most cases could be prevented if people protected themselves in the sun, and took care not to burn.

As the life-threatening melanoma is linked to sunburn in childhood, it is essential that children are protected from the sun.

In addition to the dangers of skin cancer, around 80% to 90% of chronological skin ageing is caused by the sun, and only 10% to 20% is caused by time.

The sun emits three types of ultraviolet light – UVC, which is filtered out by the earth’s atmosphere; UVB, which is mostly responsible for skin cancer; and UVA, which is the most damaging in terms of ageing the skin.

Astounding though it might seem, the majority of skin ageing – wrinkles, sagging, freckles, sun spots – is caused by exposure to sunlight.

Obviously, keeping out of the sun altogether is not an option, particularly for those who enjoy outdoor activities.

However, I would strongly advise protection from damaging rays by wearing long trousers, long-sleeved shirts, a hat and sunglasses, and frequent and liberal application of a suncream with a minimum SPF factor of 15.

And don’t forget to check that it protects from UVA rays as well as UVB.

There is no such thing as a safe tan or a healthy tan. A tan is a sign that the skin has been damaged.

Professor Judodihardjo is the medical director of the Cellite Clinic in Cardiff