Everything under the sunbeds

Last month, Cancer Research UK alerted the UK to the cancer risk posed by sunbeds. The national media lapped the story up and a series of related events conspired to produce a perfect storm of media coverage.

A mother revealed that her son had acquired severe burns during an unsupervised sunbed session, TV presenter Denise van Outen blamed facial scars on her earlier sunbed use and Which? magazine published a survey which showed that 170,000 under-16s in the UK have used a sunbed, including children as young as eight.

Shortly after, England’s Health and Safety Executive put forward revised proposals for guidelines that will restrict under-18s from using sunbeds.

Amid all this media interest, it’s easy to get carried away and forget that all of this attention is based on messages that are backed by sound scientific evidence. Let’s take a look at it.

The IARC report

Overall, the available evidence suggests that sunbeds increase the risk of skin cancer. While not all studies agree, the International Agency of Research into Cancer (IARC) recently reviewed the existing research and concluded that people who used sunbeds have a 15% higher risk of melanoma. It also found that young people who first used sunbeds before the age of 35 have 75% higher risks of the disease.

When considering these studies, scientists have to ask themselves if the results make sense from a biological point of view? And for sunbeds, the answer is a resounding yes.

UV

Ultraviolet (UV) radiation from the sun is the main cause of skin cancer. Sunbeds emit ultraviolet radiation, and while these rays come from an artificial source, they are fundamentally the same as those that reach us from the sun. And we know that UV radiation causes the majority of skin cancers by damaging that all-important molecule – DNA.

DNA is made up of strings of ‘nucleic acids’. One of these – thymine – is particularly affected by UV radiation, which has just the right amount of energy to join two neighbouring thymines together. These joined molecules cause problems by distorting the shape of the DNA helix and the information it contains, in the same way that gluing two pages of a book together makes their text unreadable.

It’s this damage that can eventually lead to skin cancer – and younger skin is particularly vulnerable. Partly, this is because it gives their skin cells a head start in accumulating enough DNA damage to turn into cancer cells. It’s also because the skin cells of growing youngsters are rapidly dividing to cover their expanding bodies.

This is why, as the IARC report showed, sunbeds have a larger impact on the risk of skin cancer if people use them at a young age.

Not just how much

And when it comes to UV radiation, studies have shown that it’s not just how much you get that matters. The pattern of exposure also counts, and sunbeds provide the sort of infrequent and intense exposures that have the greatest impact on the risk of melanoma.

Sunbeds emit two types of ultraviolet radiation – UVA and UVB.

UVB causes sunburn and melanoma skin cancer and sunbeds emit comparable amount of UVB to the midday sun. It’s this type of UV that causes sunburns in sunbed users, as graphically illustrated a few weeks ago by 13-year-old Kieron Saunders, who developed severe and infected burns to his face after visiting an unstaffed salon.

More recently, UVA has also been linked to skin cancer, and one survey found that sunbeds can emit up to 10-15 times as much UVA as the midday sun. These exposures are far higher than people would normally experience through sunbathing or daily life. Dr Philippe Autier from IARC noted that “we have little idea of the likely long-term medical consequences of such exposure.”

UVA also suppresses the immune system and ages the skin. It’s ironic then that many young people are trying to make themselves look younger and more attractive with a device that will ultimately age their skin prematurely.

Measures

So what’s to be done? For a start, it’s clear that the current optional guidelines aren’t good enough. Last year, Harry Moseley at the University of Dundee found that the sunbeds in the local area were more common than ever, and were pumping out UV radiation that was the equivalent of the Mediterranean sun. New British and European guidelines on the strength of lamps were largely ignored, and 83% of the 133 beds tested emitted levels of UVB that exceeded these guidelines.

Even so, we’re not calling for a total ban on sunbeds. We strongly believe that people have the freedom to make their own choices, but that they should be made fully aware of the relevant risks so that their choices are informed ones.

To that end, we’re calling for the governments of the UK to introduce a licensing system that will restrict use of sunbeds to people over the age of 18, provide information on risks to users and ensure that all use is supervised by trained staff.

The recent media stories have shown just how important these measures are. Undercover reporters from Which? magazine managed to book appointments for friends with pale skin in every one of the ten salons they visited, even though this group of people have particularly high risks of skin cancer.

Legislation that supports a higher age limit and better regulation have already been introduced in Scotland. The new report from the Health and Safety Executive shows they are being considered for England. It’s a move that should be applauded.

Ed

For more on sunbeds, have a look at Dr Len’s excellent piece over at Dr Len’s Cancer Blog.