Health Topics
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Healthy Living
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August 2009
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| Eye Care for Polo |
| Dr Tapas Paul |
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Polo has a long and colourful history. Played as early as the 6th century B.C. as per certain accounts, the game has come a long way from being a training methodology of army men to a game of entertainment, popular among a large number of people. |
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Initially played only on horseback, today polo has a number of variations – elephant polo, bike polo, beach polo and so on. Although now it is played indoor in many places, polo is primarily an outdoor game – played mostly under the sun. And since in any given game the spectators are more than the players, it would be good for the fans to take care of themselves – especially their eyes – this polo season.
Prolonged exposure to the sun's Ultra Violet rays can lead to premature degeneration, both on the surface of the eye as well as the most sensitive part called macula on the retina. Also, new research suggests the sun's High Energy Visible (HEV) radiation — also called "blue light" — also may increase your long-term risk of macular degeneration. People with low blood plasma levels of vitamin C and other antioxidants especially appear at risk of retinal damage from HEV radiation. While many refer to ultraviolet radiation as UV light, the term technically is incorrect because you cannot see UV rays. Therefore it becomes even more necessary to be wary of these invisible rays.
Types of UV rays
UV-C rays
These are the highest-energy UV rays, and potentially could be the most harmful to your eyes and skin. Fortunately, the atmosphere's ozone layer blocks virtually all UVC rays.
UV-B rays
These have slightly longer wavelengths and lower energy than UVC rays. These rays are filtered partially by the ozone layer, but some still reach the earth's surface. In low doses, UVB radiation stimulates the production of melanin (a skin pigment), causing the skin to darken, creating a suntan. But in higher doses, UVB rays cause sunburn that increases the risk of skin cancer. UVB rays also cause skin discolorations, wrinkles and other signs of premature aging of the skin.
UV-A rays
These are closer to visible light rays and have lower energy than UV-B and UV-C rays. But UV-A rays can pass through the cornea and reach the lens and retina inside the eye. Overexposure to UV-A radiation has been linked to the development of certain types of cataracts, and research suggests UV-A rays may play a role in development of macular degeneration.
Polo is generally played on large open fields, some times with sandy underfoot conditions. UV-B and C rays and reflections are more in open areas and also tend to get reflected from the shiny surfaces. Even if the conditions are overcast, the invisible rays manage to harm us. It is therefore best to be careful and protect oneself.
One efficient protection from harmful UV radiation is sunglasses – and they should block 100 percent of the UV rays and also absorb most of the HEV rays. Frames with a close-fitting wraparound style provide the best protection because they limit how much stray sunlight reaches your eyes from above and beyond the periphery of your sunglass lenses. In addition to sunglasses, wearing a wide-brimmed hat on sunny days can reduce your eyes' exposure to UV and HEV rays by up to 50 percent.
Risks of eye damage from UV and HEV exposure change from day to day and depend on a number of factors:
- Geographic location: UV levels are greater in tropical areas near the earth's equator. The further you are from the equator, the lower is your risk.
- Altitude: UV levels are greater at higher altitudes.
- Time of day: UV and HEV levels are greater when the sun is high in the sky, typically from 10 AM to 2 PM
- Setting: UV and HEV levels are greater in wide open spaces, especially when highly reflective surfaces are present, like snow and sand. In fact, UV exposure can nearly double when UV rays are reflected from the snow. There is less risk of UV exposure 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 and HEV radiation.
Surprisingly, cloud cover doesn't affect UV levels significantly. Your risk of UV exposure can be quite high even on hazy or overcast days. This is because UV is invisible radiation, not visible light, and can penetrate clouds.
Children Need UV Protection More
The risk of damage to our eyes and skin from solar UV radiation continues to grow as we spend time in the sun throughout our lifetime. With this in mind, it is important for children to protect their eyes from the sun. Children generally spend much more time outdoors than adults. Experts opine that as much as 80 percent of our lifetime exposure to UV rays occurs by the age of 18 years! So make sure your children's eyes are protected from the sun with good quality sunglasses. Also, encourage your child to wear a hat on sunny days to reduce UV exposure.
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. But for HEV protection, color does matter. Most sunglass lenses that block a significant amount of blue light will be bronze, copper or reddishbrown.
Risk Level Recommendations:
The grades are fixed as per EPA(Environmental Protection Agency) of the U.S.A
Low
- Wear sunglasses.
- If you get sunburns easily, use sunscreen with an SPF (Sun Protection Factor) of 15+.
Moderate
- Wear sunglasses.
- Cover up and use sunscreen
- Stay in the shade near midday, when the sun is strongest.
High
- Wear a hat and sunglasses.
- Cover up and use sunscreen.
- Reduce time in the sun between 10 AM and 4 PM
Very High
- Wear a hat and sunglasses.
- Cover up and use sunscreen.
- Minimize sun exposure between 10 AM and 4 PM
Extrem
- Wear a hat and sunglasses.
- Apply sunscreen (SPF 15+) liberally every two hours.
- Try to avoid sun exposure between 10 AM and 4 PM
With all these protections, hit the field and enjoy a smashing polo session!
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Dr Tapas Paul is Consultant ophthalmologist at Apollo Gleneagles Hospitals, Kolkata
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