Ultraviolet (UV) radiation, from natural sunlight or artificial UV rays, can damage the eye’s surface tissues as well as the cornea and lens. UV radiation can burn the front surface of the eye, comparable to sunburn on the skin.
There are three types of solar radiation; UVA, UVB, UVC. UVC rays are non-damaging but exposure to UVA and UVB can have adverse effects on your eyes and vision.
One of the short-term effects of UV radiation on the eyes is Photokeratitis, which is an inflammation of the cornea caused by a brief exposure to UV radiation, usually when combined with cold wind and snow. Like a “sunburn of the eye”, it can be painful and symptoms include red eyes, a foreign body or gritty eye sensation, extreme sensitivity to light and excessive tearing. Fortunately, this is usually temporary and rarely cause permanent damage to the eye.
Long term exposure to UV radiation has shown that exposure to small amounts of UV radiation over a period of many years may increase the chance of developing a cataract, and may cause damage to the retina, the nerve-rich lining of the eye that is used for sight. This damage to the retina is usually not reversible. Cumulative damage of repeated exposure may contribute to chronic eye disease, as well as increase the risk of developing skin cancer around the eyelids. Long-term exposure to UV light is also a risk factor in the development of ptergium (a growth that invades the corner of the eyes) and pinguecula (a yellowish, slightly raised lesion that forms on the surface tissue of the white part of your eye.)
UV Radiation Protection
It is not yet known how much exposure to UV radiation will cause how much damage, but a good recommendation is to wear quality sunglasses that offer good protection and a wide-brimmed hat when working outdoors, participating in outdoor sports, taking a walk or doing anything in the sun. To provide sufficient protection for your eyes, your sunglasses must:
• block out 99 to 100 percent of both UV-A and UV-B radiation
• screen out 75 to 90 percent of visible light
• be perfectly matched in colour with no distortions and imperfections
• have lenses that are grey for proper colour recognition
If you spend a lot of time in bright sunlight which you will if your skiing, wrap-around frames can provide extra protection from harmful UV radiation by keeping UV rays from reaching the eyes. Don’t forget children or young adults, who typically spend more time in the sun than adults. If you wear contact lenses that have UV protection, you still need to wear sunglasses. UV rays may affect the eye tissue that is not covered by the contacts. Your eyes will be more comfortable, too, with most of the bright light blocked.
REMEMBER!
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