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Sun Radiation
Exposure to the dazzling rays of the sun is a major contributing factor to skin cancer and premature aging.
How Sun Rays Damage?
Sun is the life giver. Without the sun there would be no life on mother earth. But as with everything else, too much is not good. The sunrays contain Ultraviolet rays which are considered as the biggest culprit for aging. Exposure to UV rays ages us the most then any other known reason for aging. This exposure is also the main cause of various skin cancers. Scientists are still not sure about the reason of the damage but it is stipulated that the UV rays produce free radicals in our body and these radicals cause various skin problems at a premature stage of life. Let us find out more about UV rays...
UV Rays
The UV range consists of three types-A,B and C. The wave lengths of all the three are different.
UVA (Wavelength 320-400 nm)
UVB (Wavelength 280-320 nm)
UVC (Wavelength 100-280 nm).
UVA Rays
The A type of UV is the maximum in the total UVR reaching the earth. The total UVR consists of about 90-95% of A type. The A
type penetrates deeply in the dermis, and causes direct tanning of the skin with weak sunburning. Activity of UVA radiation is much less influenced by the atmospheric and geographic factors. The UVA reaching us is more or less same even on cloudy days!
Continous exposure to UVA radiation not only accelerates aging of skin but also has been implicated in development of skin cancers.
UVB Rays
They are the most potent and harmful rays. They account for 5-10% of UVR reaching the earth. They are associated more with indirect tanning of skin, than with direct tanning. But unlike the A type they are highly influenced by atmospheric and geographic factors. UVB radiation changes substantially with cloud cover, height etc.
UVC Rays
The UVC rays normally cannot reach earth, because it is absorbed by the Ozone layer in the atmosphere. exposure to UVC can be
highly damaging to the human skin due to their high energy content. But luckily for us the Ozone layer in the atmosphere protects us from the UVC Radiation.
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