Protect Your Eyes from Ultraviolet Light Rays
Most of us will spend some time in the sun each day. Eyes, like any other parts of the body, are vulnerable to sun damage and should be taken care of, especially when we bask in the sun. This is because the sun is the greatest source of ultraviolet (UV) light, which are invisible rays that lie beyond the violet end of the visible spectrum of light.
UV rays can damage the eyes in several ways. Excessive exposure to the lowest wavelengths of UV light, also called UV-C, can cause damage to the cornea as well as the lens. Symptoms of sun damage to corneal cells can include the feeling of having a foreign body in the eye, excessive tearing and pain. These symptoms can surface between 30 minutes to 12 hours after excessive exposure to UV-C.
The high UV wavelengths, also called UV-A, are present in all outdoor environments. Excessive exposure can cause fatigue or ‘snow blindness’.
UV light exposure to the eye has also been associated with cataract formation and retinal degeneration. Cataracts usually occur with ageing but prolonged exposure to UV rays can speed up its development, as seen by a trend of sportsmen getting it now at a younger age. Pterygium has also been closely associated to the exposure of UV rays. Pterygium is a fleshy, triangular growth in the eye. It is a slow-growing, benign lesion, and mostly harmless. However, it may sometimes grow over the cornea, and in rare cases, grow large enough to cover the central cornea and affect vision.
Risks of eye damage from UV exposure change depending on a number of factors, including:
Geographic location: UV levels are greater in tropical areas near the earth’s equator. The farther you are from the equator, the lesser your risk.
Altitude: UV levels are greater at higher altitudes.
Time of day: UV levels increases when the sun is high in the sky, typically from 10 a.m. to 2 p.m.
Setting: UV levels are greater in wide open spaces, especially when highly reflective surfaces are present, like snow and sand. UV exposure is less likely in urban settings, where tall buildings shade the streets.
Medications: Certain medications, such as tetracycline, sulfa drugs, birth control pills, diuretics and tranquilizers, can increase your body’s sensitivity to UV radiation.
How to protect your eyes
Cloud cover does not affect UV levels significantly. Risk of UV exposure can be high even on hazy, overcast days. This is because UV is invisible radiation and can penetrate clouds.
The risk of damage from UV radiation is cumulative; the danger continues to grow as we spend time in the sun throughout our lifetime.
It is especially important for kids to protect their eyes from the sun. Children generally spend much more time outdoors. In fact, experts say nearly 50 per cent (or more) of our lifetime exposure to UV rays may occur by age 18, given that many children spend significantly more time outdoors than the average adult.
How to choose a good pair of sunglasses
To best protect our eyes from the sun’s harmful UV rays, always wear good quality sunglasses when outdoors.
Look for sunglasses that block 100 per cent of UV rays. To protect as much of the delicate skin around your eyes as possible, try at least one pair of sunglasses with large lenses or a close-fitting wraparound style.
The amount of UV protection sunglasses provide is unrelated to the color and darkness of the lenses. A light amber-colored lens can provide the same UV protection as a dark gray lens. Your optician or optometrist can help you choose the best sunglass lenses for your needs.
Even if your contact lenses block UV rays, you still need sunglasses. UV-blocking contacts shield only part of your eyes under the lens. UV rays can still damage the conjunctiva and other tissues not covered by the contact lens. Wearing sunglasses protects these delicate tissues and the skin around your eyes from UV damage.
In addition to sunglasses, wearing a wide-brimmed hat on sunny days can reduce your eyes’ exposure to UV by up to 50 per cent.
So, remember to have your sunglasses with you when you are out there in the sun. 🙂