Diagram: A healthy skin is undeniably an important element of healthy life. (My Healthy Soul, 2010)Skin cancer is a type of cancer that forms in the skin tissues. Skin cancer has been the most common type of cancer in United States. Skin cancer that forms in the lower part of the epidermis is called basal cell carcinoma whereas squamous cell carcinoma is the skin cancer that forms in squamous cells. These two most common types of cancer are more highly curable as compared to the third type of skin cancer – melanoma, which is more dangerous.
Diagram: An example of melanoma skin cancer. (Health Line, 2011)
Most skin cancers form in older people on parts of the body exposed to the sun or in people who have weakened immune system. The UV light contained in the sunlight causes the cells to mutate and begin to grow and divide more quickly than normal cells do. These abnormal cells will clump together to form tumors in other parts of body and thus causing cancer to occur.
UV radiation is part of the electromagnetic (light) spectrum that reaches the earth from the sun. Apart from the sun, UV rays can also come from the tanning beds and sunlamps. UV rays are an invisible kind of radiation due to their shorter wavelengths than visible light which make them invisible to the naked eyes. The three types of UV rays include Ultraviolet A (UVA), Ultraviolet B (UVB), and Ultraviolet C (UVC).
UV radiation is part of the electromagnetic (light) spectrum that reaches the earth from the sun. Apart from the sun, UV rays can also come from the tanning beds and sunlamps. UV rays are an invisible kind of radiation due to their shorter wavelengths than visible light which make them invisible to the naked eyes. The three types of UV rays include Ultraviolet A (UVA), Ultraviolet B (UVB), and Ultraviolet C (UVC).
Diagram: How ultraviolet rays travel to the Earth. (Nathan, 2009)
UVA has the wavelength of 320-400 nm which is the longest among them. UVA is the most common type of sunlight present at the earth’s surface, and reaches beyond the top layer of human skin. It is believed that UVA rays can damage connective tissues and eventually increase a person’s risk of skin cancer. On the other hand, UVB rays are less common at the earth’s surface since most UVB rays are absorbed by the ozone layer. Although UVB rays do not reach as far into the skin as UVA rays, they can still be damaging. With even shorter wavelengths which are extremely dangerous, most UVC rays are absorbed by the ozone layer and do not reach the earth’s surface.
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