Sunlight arrives on Earth in three forms; infrared (heat), visible light and ultraviolet radiation (UVR) in the form of UVA (315 to 400 nm wavelength), UVB (280 to 315 nm wavelength), and UVC (100 to 280 nm wavelength) rays. However, UVC rays don’t actually reach the Earth as they are filtered out by the Ozone Layer; hence we need only really worry about UVA and UVB rays for the time being.
UVA light penetrates deeper into the skin than UVB light and is thought to be a prime cause of photoageing; characterised by wrinkles, dark blotches, freckles, leathery skin and a loss of skin elasticity. 99% of the ultraviolet radiation that reaches the Earth's surface is actually UVA, yet deceptively we mostly hear about worries concerning UVB radiation, as it is this form that causes the visibly noticeable “tan” and “sunburn”.
As a natural defense against UVR, the body, depending on the skin type of the individual, tans when exposed to moderate levels of UVR by releasing the brown pigment melanin. This helps the skin to block the penetration of the UV rays by absorbing the UV light, and prevent damage to the vulnerable tissues deeper down.
However, sunburn occurs when the exposure to UV light exceeds that of the protective capacity of a person's melanin. Melanin content varies greatly but in general darker skinned people have more melanin than lighter skinned.
Sunburn is usually not immediately obvious. After being burnt, skin may turn red 2 to 6 hours later, with pain at its worst 6 to 48 hours afterwards. The burn continues to develop for 24 to 72 hours after the incident and skin peeling begins 3 to 8 days after the burn occurs. The major danger of sunburn however is the increased risk of future skin cancer such as melanoma.
One of the interesting and generally little known things about UVR is that it is reflected by different surfaces. These reflections can amplify the effects of UV exposure. For example, snow reflects 90% of UV light; which is why you can get snow blindness and severe sunburns from skiing on a sunny day. Sand can also reflect up to 20% of UVB light that hits it, meaning that you can get extra UV exposure at the beach.
Pleasingly, in our survey only 6% of people admitted to regularly sunbathing, whilst 61% stated only occasional sun worshipping and a healthy 33% never sunbathe at all.
With the advent of commercial sun bed salons on every high street, and recent media stories of “tanorexia”, the addiction to visiting these UV producing machines; we were pleased to note that our survey revealed that it seems the message about the dangers is finally getting through, with no one admitting regular use and 74% stating that they never use sunbeds.
88% of people knew that their skin would age more quickly if they spent time in the sun, yet the Western attitude towards the desirability of having a tan still persists, with over 60% of people agreeing that having a tan makes then look healthier and more attractive. However, with the results above suggesting a move away from sunbathing and sunbed use, it was no surprise to note that over half of people regularly or occasionally resort to fake tanning products to give them the desirable result without the damage caused by UV exposure.