Ultraviolet Radiation from the Sun and Skin Cancer Risk ( UVA, UVB, UVC )

In daily life, God has met all the needs we are, one of them is the sunlight, according to necessary and benefical to the body. The sun's rays contain ultraviolet B radiation (UVB) in small number of exposed skin and absorbed. It will stimulate the formation of vitamin D3. Therefore, in the spring time ( summer time ) in Europe, many peope are sunbathing to nourish the body.

But since the last two decades, the sun when the beginning is friendly indirect to be threat to health. It happens because the result of our own actions so that the layer of ozone in the stratosphere that serves to filter (filter) ultraviolet radiation (UVR) from year to year become thinner and thinner due to chemical pollution chlorofluoro carbon (CFC) derived from the engine cooling (air conditioners, refrigerators) and industry. Depletion of the ozone layer, will cause the higher the intensity of ultraviolet radiation that reach the earth. Several studies have reported that each decade (since 1970) the ozone layer to be reduced 3% and will increase the radiation exposure Ultraviolet by 12% in the earth's surface. An increase in the intensity of ultraviolet radiation, especially UVB, due to depletion of the ozone layer in the stratosphere will impact quite seriously on living beings on earth.

Ultraviolet radiation is electromagnetic radiation at wavelengths between 100 nm (equivalent to about 12 eV photon energy) to 400 nm (nano meters). Ultraviolet radiation emitted by the sun is divided into 3 regions namely UVA, UVB and UVC that depend on the wavelength and the biological effects.

The division of the ultraviolet radiation (UVR) and its relationship with biological effects.

Area	The Spectrum Range (nm)	Biological effects on the eye	Biological effects on the skin
UVC UVB  UVA	100 – 280 280 – 315  315 – 400	Photo of  keratin Photo of keratitis,Cataract Cataract	Anemia of Cancer Erythema Cancer Pigment darkening, Accelerated aging